TWI753299B - Optical filters and their uses - Google Patents

Abstract

An object of the present invention is to provide an optical filter which has both low incident angle dependence in the near-infrared region and excellent red transmittance characteristics, and which improves ghosting. The optical filter of the present invention is characterized by satisfying the following requirements (A) to (D): (A) in the wavelength range of 430 nm to 580 nm, the average value of transmittance measured from the vertical direction is 75% or more ; (B) in the range of wavelength 800nm~1000nm, the average value of transmittance when measured from the vertical direction is less than 10%; (C) in the range of wavelength 700nm~750nm, the transmittance when measured from the vertical direction The average value exceeds 46%; (D) in the wavelength range of 560nm ~ 800nm, the value of the shortest wavelength with a transmittance of 50% when measured from the vertical direction (Ya) and when measured from an angle of 30° from the vertical direction The absolute value of the difference between the shortest wavelength values (Yb) with a transmittance of 50% is less than 15 nm.

Description

Optical filters and their uses

The present invention relates to an optical filter and its use. Specifically, it relates to an optical filter having specific optical properties (eg, a near-infrared cut filter), and a solid-state imaging device and a camera module using the optical filter.

Solid-state imaging devices such as video cameras, digital still cameras, and mobile phones with camera functions use charge-coupled devices (CCDs) or complementary metal oxide semiconductors (CMOS) as solid-state imaging elements for color images. image sensor. These solid-state imaging devices use a sensor having sensitivity to near infrared rays in the light-receiving portion thereof, and therefore require correction of the viewing sensitivity, and optical filters (for example, near-infrared cutoff filters) are often used.

As the optical filter, an optical filter manufactured by various methods has been conventionally used. For example, a near-infrared cut filter with a near-infrared reflective film in which a dielectric multilayer film is laminated on a norbornene-based resin is known. device (for example, refer to Patent Document 1). However, in the near-infrared cut filter having the near-infrared reflective film, the light transmission characteristic has a large incident angle dependence, and in a solid-state imaging device with a wide angle of view, the color tone is different between the center and the peripheral portion of the image. bad condition.

Optical filters such as near-infrared cut filters containing a near-infrared absorbing agent are widely known as an example of improving the incident angle dependence. Specifically, a near-infrared cut filter is known that uses a resin as a base material and contains a near-infrared absorber having steep absorption characteristics in the resin to improve the incident angle dependence in the near-infrared region (for example, Refer to Patent Document 2).

In recent years, an image sensing system that detects not only the wavelengths of 400 nm to 700 nm, which have high human visual sensitivity, but also near-infrared rays to measure the degree of growth of plants or the amount of oxidized hemoglobin in humans has been studied (for example, see Patent Document 3 and Patent Document 4). ). For example, in Patent Document 3, it is known that the reflectance of rice leaves at a wavelength of 500 nm to 800 nm changes depending on the nitrogen content, and a method of obtaining a plant growth index from the reflected intensity of visible light and the reflected intensity of near-infrared light is proposed.

In addition, it is known that the ratio (F690/F740) of the fluorescence intensity (F690) of the wavelength of 690 nm to the fluorescence intensity of the wavelength of 740 nm (F740) can be used as a measure of the chlorophyll concentration in plant organisms, for example, using an ultraviolet laser with a wavelength of 355 nm as a light source. Vegetation diagnosis is performed based on the index (for example, refer to Non-Patent Document 1).

However, in an image sensing system combining visible light and near-infrared rays with wavelengths of 400 nm to 700 nm, the wavelength of 700 nm used for detection is used in optical filters such as near-infrared cut-off filters containing near-infrared absorbing agents. The light transmittance of ~750nm is low, and it is difficult to maintain sufficient sensitivity.

In a near-infrared cut filter having a near-infrared reflective film laminated with a dielectric multilayer film, by increasing the thickness of the laminated dielectric multilayer film, Long wavelength shift of the reflection band. Therefore, it is easy to provide a dielectric multilayer film with a high transmittance at a wavelength of 700 nm to 750 nm. However, in the near-infrared cut filter, there is a problem that the incidence angle dependence at high angle incidence is large, and it is difficult to image At the center and the periphery of the image, the intensity of light obtained by sensing differs depending on the angle of incidence.

In addition, the performance of the solid-state imaging element has been advanced, and in the conventional optical filter, the image quality may be degraded due to the ghost generated by the reflection of the optical filter. In particular, due to reflection by the optical filter caused by light with wavelengths of 680 nm to 720 nm, ghosting caused by a part of stray light re-entering other positions of the sensor becomes a problem. Therefore, it is required to reduce the reflectance at wavelengths of 680 nm to 720 nm.

However, the conventional optical filter cannot sufficiently satisfy the requirement of both the suppression of the ghost and the enhancement of the red sensor sensitivity.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 4513420

[Patent Document 2] Japanese Patent Laid-Open No. 2012-8532

[Patent Document 3] Japanese Patent Laid-Open No. 2016-146784

[Patent Document 4] International Publication No. 2018/123676 Manual

[Non-patent literature]

[Non-Patent Document 1] H.K.Lichtenthaler et al.: "Detection of Vegetation Stress Via a New High Resolution Fluorescence Imaging System",. Plant Physiol., 148, 599-612 (1996)

An object of the present invention is to provide an optical filter and a device using the optical filter which have both low incident angle dependence in the near-infrared region and transmittance of light having a wavelength of 700 nm to 750 nm required for sensing The characteristics are excellent, and ghosting is improved.

The optical filter of one aspect of the present invention is characterized by satisfying the following requirements (A) to (D):

(A) The average value of transmittance when measured from a direction perpendicular to the surface of the optical filter in a wavelength range of 430 nm to 580 nm is 75% or more.

(B) The average value of transmittance when measured from a direction perpendicular to the surface of the optical filter in a wavelength range of 800 nm to 1000 nm is 10% or less.

(C) The average value of transmittance when measured from the direction perpendicular to the surface of the optical filter in the wavelength range of 700 nm to 750 nm exceeds 46%.

(D) The value (Ya) of the shortest wavelength with a transmittance of 50% when measured from a direction perpendicular to the surface of the optical filter in the wavelength range of 560 nm to 800 nm The absolute value of the difference between the shortest wavelength values (Yb) at which the transmittance is 50% when the direction is measured at an angle of 30° is less than 15 nm.

According to the present invention, an optical filter and the use of the optical filter can be provided A wave filter device, the optical filter has both low incident angle dependence in the near-infrared region, excellent transmittance characteristics of light with a wavelength of 700 nm to 750 nm required for sensing, and improved ghosting. The optical filter of the present invention is suitable as a near-infrared cut filter.

1: Optical filter

10: Substrate

11: Support body

12: Resin layer

13: Other functional films

21: Near infrared reflective film

22: Near infrared reflective film

201: Detector

301: Lens

302: Sensor

303: Bandpass filter

304: Normal detection department

305, 306, 402: Ghosting

400: Camera Module

401: light source

FIG. 1 is a schematic diagram showing an example of an optical filter of the present invention.

FIG. 2 is a schematic diagram showing an example of the optical filter of the present invention.

Figure 3 shows the data of the intensity of different wavelengths after normalizing the exposure data in Gifu on a certain date to a maximum value of 1.0, published by the National Research and Development Corporation for New Energy Industrial Technology Development.

FIG. 4 is an example of different wavelength sensitivities of green and near-infrared sensor pixels.

FIG. 5 is a diagram showing the optical characteristics of a transmission filter in a dual wavelength region that transmits green and near-infrared rays produced for evaluating green sensitivity and near-infrared sensitivity.

6 is a schematic diagram showing an example of a method of measuring the transmittance when measured from a direction perpendicular to the surface of the optical filter.

7 is a schematic diagram showing an example of a method of measuring the transmittance at an angle of 30° from a direction perpendicular to the surface of the optical filter.

8 is a schematic diagram showing an example of a method of measuring the reflectance of light incident at an angle of 5° from a direction perpendicular to the surface of the optical filter.

9(a) and 9(b) are schematic diagrams showing examples of camera modules.

FIG. 10 is a schematic diagram showing an example of a ghost generation mechanism in the camera module.

FIG. 11 is a schematic diagram showing an example of ghosting.

FIG. 12 is a graph showing the optical characteristics of the optical filter obtained in Example 1. FIG.

13 is a graph showing the optical characteristics of the optical filter obtained in Example 5. FIG.

FIG. 14 is a graph showing the optical characteristics of the optical filter obtained in Comparative Example 1. FIG.

FIG. 15 is a graph showing the optical characteristics of the optical filter obtained in Comparative Example 4. FIG.

FIG. 16 is a graph showing the optical characteristics of the optical filter obtained in Comparative Example 7. FIG.

Embodiments of the present invention will be described based on the drawings as necessary, but these drawings are provided for illustration only, and the present invention is not limited to these drawings at all. In addition, it should be noted that the drawings are schematic, and the relationship between the thickness and the plane size, the thickness ratio, and the like are different from actual ones. Furthermore, in the following description, the same code|symbol is attached|subjected about the structural application which has the same or substantially the same function and structure, and a repeated description is abbreviate|omitted. As one Embodiment of the optical filter of this invention, as shown in FIG. 1, the aspect which has the base material 10, the near-infrared reflection film 21, and the near-infrared reflection film 22 is mentioned. In addition, as shown in FIG. 2 , the optical filter of the present invention may have other functional films 13 .

[optical filter]

The optical filter of the present invention satisfies the following requirements (A) to (D).

(A) The average value of transmittance when measured from a direction perpendicular to the surface of the optical filter in a wavelength range of 430 nm to 580 nm is 75% or more.

(B) The average value of transmittance when measured from a direction perpendicular to the surface of the optical filter in a wavelength range of 800 nm to 1000 nm is 10% or less.

(C) In the wavelength range of 700nm~750nm, from relative to the optical filter The average value of transmittance measured in the direction perpendicular to the surface of the device exceeded 46%.

(D) The value (Ya) of the shortest wavelength with a transmittance of 50% when measured from a direction perpendicular to the surface of the optical filter in the wavelength range of 560 nm to 800 nm The absolute value of the difference between the shortest wavelength values (Yb) at which the transmittance is 50% when the direction is measured at an angle of 30° is less than 15 nm.

By using an optical filter that satisfies the requirement (A), the amount of light captured by the solid-state imaging element can be increased within a wavelength range of 430 nm to 580 nm. The average value of the transmittance in the requirement (A) is preferably 80% or more. If it is 80% or more, shooting can be performed even in a darker environment.

By using an optical filter that satisfies the requirement (B), the amount of light taken in by the solid-state imaging element can be reduced in the wavelength range of 800 nm to 1000 nm. In this way, light that is invisible to human eyes and unnecessary for sensing can be shielded. The average value of the transmittance in the requirement (B) is preferably 7% or less, more preferably 6% or less, and still more preferably 5% or less.

By using an optical filter that satisfies the requirement (C), the amount of light captured by the solid-state imaging element is secured within a wavelength range of 700 nm to 750 nm, and the sensing sensitivity is improved. The average value of the transmittance in the requirement (C) is preferably 55% or more, more preferably 65% or more, and still more preferably 75% or more. The higher the transmittance, the better, but, for example, the upper limit is preferably 100%, more preferably 90%, and still more preferably 80%. Within the range, the amount of light taken in by the solid-state imaging element is adjusted, and light required for sensing can be transmitted efficiently.

By using an optical filter that satisfies the requirement (D), it is possible to reduce the amount of light incident on the solid-state imaging element in the wavelength range of 560 nm to 800 nm. corner dependency. As a result, the incident angle dependence of the spectral sensitivity of the solid-state imaging element in this wavelength range can be reduced. The smaller the incident angle dependence, the smaller the color perception between the center and the periphery of the image obtained by the solid-state imaging element, or the difference in the sensor sensitivity, and the higher the sensitivity.

It is further preferable that the optical filter of the present invention satisfies the following requirement (E).

(E) The value (Ya) of the wavelength in the above-mentioned requirement (D) is 730 nm or more and 800 nm or less.

By using an optical filter that satisfies the requirement (E), it is easy to maintain high transmittance of visible light with wavelengths of 400 nm to 700 nm, transmittance of near-infrared rays with wavelengths of 700 nm to 750 nm used for sensing, and inconvenience of sensing. Low transmittance (high shielding) at the required wavelength of 800nm to 1200nm. The wavelength (Ya) is preferably 740 nm or more and 800 nm or less, and more preferably 745 nm or more and 800 nm or less.

It is further preferable that the optical filter of the present invention satisfies the following requirements (Z1) and (Z2).

(Z1) The reflectance when measured at an angle of 5° from a direction perpendicular to the surface of the optical filter at a wavelength of 700 nm is 10% or less when incident from any surface of the optical filter.

(Z2) The value (Za) of the shortest wavelength with a reflectance of 50% when measured at an angle of 5° from a direction perpendicular to the surface of the optical filter in the wavelength range of 600 nm or more When incident on one surface, both are 730 nm or more.

By using an optical filter that satisfies the necessary conditions (Z1) and (Z2), it is possible to suppress the Controls the generation of ghost images caused by light reflected by the optical filter.

A near-infrared reflective film including a dielectric multilayer film tends to shift the reflection band to a shorter wavelength as the incident is obliquely at a higher angle from the surface of the optical filter. Therefore, the wavelength (Za) in the above-mentioned necessary condition (Z2) is more preferably 740 nm or more, more preferably 750 nm or more, and still more preferably 780 nm or more. Thereby, in the light recognized by the human eye, even in the light incident at a high angle with respect to the surface of the optical filter, the occurrence of ghost images can be sufficiently suppressed.

The optical filter of the present invention preferably includes a base material containing a near-infrared absorbing agent and a near-infrared reflective film.

An optical filter having a base material containing a near-infrared absorbing agent can suppress reflection of near-infrared rays of the optical filter, and can reduce ghost images. An optical filter having a near-infrared reflective film is excellent in near-infrared shielding performance and excellent in transmission performance of visible light in the wavelength range of 430 nm to 580 nm, and the obtained solid-state imaging device can be highly sensitive.

In the case where the near-infrared absorber has an absorption maximum wavelength in a wavelength range of 751 nm to 950 nm, and the near-infrared absorber is contained in an amount of 10% of the transmittance of the substrate at the absorption maximum wavelength, Preferably, the longest wavelength (Aa) in which the transmittance of the substrate is 70% in the range of wavelength 430 nm or more and the absorption maximum wavelength or less, and the transmittance of the substrate in the range of wavelength 580 nm or more is 30%. The absolute value of the difference between the shortest wavelengths (Ab) is less than 150 nm.

By using an optical filter having a base material containing a near-infrared absorber whose absolute value of the difference between (Aa) and (Ab) is less than 150 nm, it is easy to have both The transmittance of near-infrared rays with wavelengths of 700 nm to 750 nm and the low transmittance of wavelengths of 800 nm to 1200 nm, which are not necessary for sensing, (high shielding properties) are maintained high. The absolute value of the difference is preferably as small as possible, more preferably less than 100 nm, and still more preferably less than 70 nm. The lower limit is 1 nm.

As the characteristics of the near-infrared absorber in a preferable range, it has an absorption maximum wavelength at a wavelength of 751 nm to 950 nm, and the absolute value of the difference between the (Aa) and the (Ab) is less than 150 nm, and the absorber can be satisfied. A characteristic of one, or a mixture of several characteristics. In addition, the near-infrared absorber in which a plurality of kinds are mixed may contain substances that cannot satisfy the characteristics alone.

[Substrate]

The base material preferably has transparency. Transparency as used in the present invention means that the average value of transmittance in the wavelength range of 420 nm to 600 nm is 50% or more. Examples of the material of the substrate include special glass and resins such as glass, tempered glass, phosphoric acid glass, fluorophosphoric acid glass, alumina glass, yttrium aluminate, and yttrium oxide.

In addition, the base material may be composed of one layer or multiple layers, may be composed of one material selected from the above-mentioned materials, may be composed of a plurality of materials, and may be appropriately mixed materials. At least one of the layers constituting the base material preferably contains a near-infrared absorber, and may also contain a near-ultraviolet absorber. The layer containing the near-infrared absorber and the layer containing the near-ultraviolet absorber may be the same layer or different layers.

<glass>

As said glass, a silicate glass, a soda lime glass, a borosilicate glass, a quartz glass, etc. are mentioned, for example.

<Strengthened glass>

As said tempered glass, physical tempered glass, tempered laminated glass, chemical tempered glass, etc. are mentioned, for example. Among these, the thickness of a compression layer is thin, and the chemically strengthened glass which can process the thickness of a base material thinly is preferable. Specific examples of chemically strengthened glass include "Dragontrail" manufactured by Asahi Glass Co., Ltd., "Gorilla Glass" manufactured by Corning Corporation, and the like.

<Special glass>

Examples of the phosphoric acid glass or the fluorophosphoric acid glass include BS3, BS4, BS6, BS7, BS8, BS10, BS11, BS12, BS13, BS16, BS17, etc. manufactured by Matsunami Glass Co., Ltd., International Publication No. 2012/018026 Fluorophosphate-based glass and the like described in No. As said alumina glass, "hiceram" etc. are mentioned, for example by Nippon Koshi Corporation. Examples of the yttrium aluminate or the yttrium oxide include "EXYRIA (registered trademark)" manufactured by CoorsTek, Inc., and the like.

<resin>

Examples of the resin include polyester-based resins, polyether-based resins, acrylic resins, polyolefin-based resins, polycycloolefin-based resins, norbornene-based resins, polycarbonate-based resins, and enethiol-based resins , epoxy resin, polyamide resin, polyimide resin, polyurethane resin, polystyrene resin, etc. Among these, norbornene-based resins, polyimide-based resins, and polyether-based resins are preferred.

The refractive index of the resin can be adjusted by a method of adjusting the molecular structure of the raw material components or the like. Specifically, the main chain or side of the polymer of the raw material component can be mentioned. A method by which a chain imparts a specific structure. The structure provided in the polymer is not particularly limited, and examples thereof include norbornene skeleton and fluorene skeleton.

As the resin, a commercial item can be used. Commercially available products include "ogsol (registered trademark) EA-F5003" (acrylic resin, refractive index: 1.60) manufactured by Osaka Gas Chemical Co., Ltd., "Ogsol (registered trademark) EA-F5003" manufactured by Tokyo Chemical Industry Co., Ltd. "Polymethyl methacrylate" (refractive index: 1.49), "polyisobutyl methacrylate" (refractive index: 1.48) manufactured by Tokyo Chemical Industry Co., Ltd., manufactured by Mitsubishi Rayon Co., Ltd. "BR50" (refractive index: 1.56), etc.

In addition, examples of commercially available polyester resins include "OKP4HT" (refractive index: 1.64), "OKP4" (refractive index: 1.61), and "B-OKP2" (refractive index: 1.61) manufactured by Osaka Gas Chemical Co., Ltd. As the polycarbonate resin Commercially available products include, for example, "LeXan (registered trademark) ML9103" (refractive index: 1.59), "xylex (registered trademark) 7507" manufactured by Sabic, Mitsubishi "EP5000" (refractive index: 1.63) manufactured by Gas Chemical Co., Ltd., "SP3810" (refractive index: 1.63), "SP1516" (refractive index: 1.60), "TS2020" (refractive index) manufactured by Teijin Chemical Co., Ltd. : 1.59) and the like, and commercial products of norbornene-based resins include, for example, "ARTON" (registered trademark) (refractive index: 1.51) manufactured by JSR Co., Ltd., "ZEONEX (registered trademark)" (refractive index: 1.53) manufactured by ZEON Co., Ltd., etc.

Polyether-based resins are obtained by the reaction of forming ether bonds on the main chain The polymer is preferably a polymer having at least one structural unit selected from the group consisting of structural units represented by the following formulae (1) and (2). In addition, it may have a structural unit represented by the following formula (3).

In the formula (1), R ¹ to R ⁴ each independently represent a monovalent organic group having 1 to 12 carbon atoms. a to d each independently represent an integer of 0 to 4, preferably 0 or 1, more preferably 0.

Examples of the monovalent organic group having 1 to 12 carbon atoms include a monovalent hydrocarbon group having 1 to 12 carbon atoms, and a monovalent organic group having 1 to 12 carbon atoms containing at least one atom selected from the group consisting of an oxygen atom and a nitrogen atom. Valence organic base, etc.

Examples of the monovalent hydrocarbon group having 1 to 12 carbon atoms include linear or branched hydrocarbon groups having 1 to 12 carbon atoms, alicyclic hydrocarbon groups having 3 to 12 carbon atoms, and aromatic hydrocarbon groups having 6 to 12 carbon atoms.

The linear or branched hydrocarbon group having 1 to 12 carbon atoms is preferably a linear or branched hydrocarbon group having 1 to 8 carbon atoms, more preferably a linear or branched hydrocarbon group having 1 to 5 carbon atoms. .

Preferred specific examples of the linear or branched hydrocarbon group include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl and n-heptyl, etc.

The alicyclic hydrocarbon group having 3 to 12 carbon atoms is preferably an alicyclic hydrocarbon group having 3 to 8 carbon atoms, and more preferably an alicyclic hydrocarbon group having 3 or 4 carbon atoms.

Preferred specific examples of the alicyclic hydrocarbon group having 3 to 12 carbon atoms include cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; Cycloalkenyl such as hexenyl. The bonding site of the alicyclic hydrocarbon group may be any carbon on the alicyclic ring.

Examples of the aromatic hydrocarbon group having 6 to 12 carbon atoms include phenyl and biphenyl. base and naphthyl, etc. The bonding site of the aromatic hydrocarbon group may be any carbon on the aromatic ring.

Examples of the organic group having 1 to 12 carbon atoms including an oxygen atom include organic groups including a hydrogen atom, a carbon atom, and an oxygen atom, and among them, the total carbon number including an ether bond, a carbonyl group, an ester bond, and a hydrocarbon group is preferably used. 1~12 organic groups, etc.

Examples of organic groups having 1 to 12 carbon atoms in total including ether bonds include alkoxy groups having 1 to 12 carbon atoms, alkenyloxy groups having 2 to 12 carbon atoms, alkynyloxy groups having 2 to 12 carbon atoms, and alkynyloxy groups having 2 to 12 carbon atoms. Aryloxy group of to 12, alkoxyalkyl group of carbon number of 1 to 12, etc. Specifically, methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, phenoxy group can be mentioned , propyleneoxy, cyclohexyloxy and methoxymethyl, etc.

Examples of the organic group having a carbonyl group having 1 to 12 carbon atoms in total include an acyl group having 2 to 12 carbon atoms, and the like, and specifically, an acetyl group, a propionyl group, an isopropyl group, a benzyl group, and the like. .

Examples of the organic group having 1 to 12 carbon atoms in total including an ester bond include acyloxy groups having 2 to 12 carbon atoms, and the like. Benzyloxy, etc.

Examples of the nitrogen atom-containing organic group having 1 to 12 carbon atoms include organic groups including hydrogen atoms, carbon atoms, and nitrogen atoms, and specifically, cyano groups, imidazolyl groups, triazolyl groups, benzimidazolyl groups, and Benzotriazolyl, etc.

Examples of the organic group having 1 to 12 carbon atoms including an oxygen atom and a nitrogen atom include organic groups including a hydrogen atom, a carbon atom, an oxygen atom and a nitrogen atom, and specifically, an oxazolyl group, an oxadiazolyl group, benzoxazolyl and benzoxadiazolyl, etc.

R ¹ to R ⁴ in the formula (1) are preferably monovalent hydrocarbon groups having 1 to 12 carbon atoms, more preferably 6 carbon atoms, from the viewpoint of water absorption (wetting) of the resin (1). An aromatic hydrocarbon group of ~12, more preferably a phenyl group.

In the formula (2), R ¹ to R ⁴ and a to d have the same meanings as R ¹ to R ⁴ and a to d in the formula (1), respectively, and Y represents a single bond, -SO ₂ - Or -CO-, R ⁷ and R ⁸ each independently represent a halogen atom, a monovalent organic group having 1 to 12 carbon atoms, or a nitro group, and m represents 0 or 1. Wherein, when m is 0, R ⁷ is not cyano. g and h each independently represent an integer of 0 to 4, preferably 0.

As the monovalent organic group having 1 to 12 carbon atoms, the same ones as the monovalent organic group having 1 to 12 carbon atoms in the above formula (1) can be mentioned.

In the resin (1), from the viewpoint of optical properties, heat resistance, and mechanical properties, the molar ratio of the structural unit (1) and the structural unit (2) (wherein both (the structural unit ( The total of 1) + structural unit (2)) is 100), preferably structural unit (1): structural unit (2)=50: 50~100: 0, more preferably structural unit (1): structural unit (2 )=70:30~100:0, more preferably, structural unit (1): structural unit (2)=80:20~100:0. In addition, in this specification, the mechanical properties refer to properties such as tensile strength, elongation at break, and tensile modulus of elasticity of the resin.

In addition, the resin (1) may further have at least one structural unit selected from the group consisting of a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4) (hereinafter Also known as "building block (3-4)"). When the resin (1) has the structural unit (3-4), the mechanical properties of the base material containing the resin (1) are improved, which is preferable.

In the formula (3), R ⁵ and R ⁶ each independently represent a monovalent organic group having 1 to 12 carbon atoms, and Z represents a single bond, -O-, -S-, -SO ₂ -, -CO-, -CONH-, -COO- or a divalent organic group with 1 to 12 carbon atoms, and n represents 0 or 1. e and f each independently represent an integer of 0 to 4, preferably 0.

Examples of the monovalent organic group having 1 to 12 carbon atoms include the same groups as those of the monovalent organic group having 1 to 12 carbon atoms in the above formula (1).

Examples of the divalent organic group having 1 to 12 carbon atoms include a divalent hydrocarbon group having 1 to 12 carbon atoms, a divalent halogenated hydrocarbon group having 1 to 12 carbon atoms, and a group containing 1 to 12 carbon atoms selected from the group consisting of an oxygen atom and a nitrogen atom. Divalent organic group having 1 to 12 carbon atoms having at least one atom, and a divalent halogenated organic group having 1 to 12 carbon atoms having at least one atom selected from the group consisting of an oxygen atom and a nitrogen atom.

Examples of the divalent hydrocarbon group having 1 to 12 carbon atoms include a linear or branched divalent hydrocarbon group having 1 to 12 carbon atoms, a divalent alicyclic hydrocarbon group having 3 to 12 carbon atoms, and a divalent hydrocarbon group having 6 to 12 carbon atoms. Aromatic hydrocarbon groups, etc.

Examples of the linear or branched divalent hydrocarbon group having 1 to 12 carbon atoms include methylene, ethylidene, trimethylene, isopropylidene, pentamethylene, hexamethylene, and heptamethylene. Wait.

Examples of the divalent alicyclic hydrocarbon group having 3 to 12 carbon atoms include cycloalkylene groups such as cyclopropylidene, cyclobutylene, cyclopentylene, and cyclohexylene; cyclobutenyl, cyclopentene, etc. cycloalkenyl such as cyclohexenyl and cyclohexenyl, etc.

As a C6-C12 divalent aromatic hydrocarbon group, a phenylene group, a naphthylene group, a biphenylene group, etc. are mentioned.

Examples of the divalent halogenated hydrocarbon group having 1 to 12 carbon atoms include linear or branched divalent halogenated hydrocarbon groups having 1 to 12 carbon atoms, divalent halogenated alicyclic hydrocarbon groups having 3 to 12 carbon atoms, and 6 to 12 carbon atoms. Divalent halogenated aromatic hydrocarbon groups, etc.

Examples of the linear or branched divalent halogenated hydrocarbon group having 1 to 12 carbon atoms include difluoromethylene, dichloromethylene, tetrafluorovinyl, tetrachlorovinyl, hexafluorotrimethylene, and hexachloroethylene. Trimethylene, hexafluoroisopropyl and hexachloroisopropyl.

As the divalent halogenated alicyclic hydrocarbon group having 3 to 12 carbon atoms, at least a part of the hydrogen atoms of the groups exemplified in the above-mentioned bivalent alicyclic hydrocarbon group having 3 to 12 carbon atoms are fused with a fluorine atom, a chlorine atom, a bromine atom or A base substituted by an iodine atom, etc.

Examples of the divalent halogenated aromatic hydrocarbon group having 6 to 12 carbon atoms include fluorine, chlorine, bromine or iodine atoms in at least a part of the hydrogen atoms of the groups exemplified in the above-mentioned divalent aromatic hydrocarbon groups having 6 to 12 carbon atoms. Substituted bases, etc.

Examples of the organic group having 1 to 12 carbon atoms containing at least one atom selected from the group consisting of oxygen atoms and nitrogen atoms include organic groups containing hydrogen atoms, carbon atoms, and oxygen atoms and/or nitrogen atoms, The divalent organic group etc. which have an ether bond, a carbonyl group, an ester bond, an amide bond, and a hydrocarbon group in total of 1-12 carbon atoms are mentioned.

Specific examples of the divalent halogenated organic group containing 1 to 12 carbon atoms containing at least one atom selected from the group consisting of oxygen atoms and nitrogen atoms include those containing the group selected from the group consisting of oxygen atoms and nitrogen atoms. A group in which at least a part of hydrogen atoms of the groups exemplified in the divalent organic group having 1 to 12 carbon atoms of at least one atom in the group is substituted with a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, and the like.

As Z in the formula (3), preferably a single bond, -O-, -SO ₂ -, -CO- or a divalent organic group having 1 to 12 carbon atoms, the water absorption (wet) of the resin (1) In terms of ) properties, it is more preferably a divalent hydrocarbon group having 1 to 12 carbon atoms, a divalent halogenated hydrocarbon group having 1 to 12 carbon atoms, or a bivalent alicyclic hydrocarbon group having 3 to 12 carbon atoms.

The base material preferably has a resin layer containing a near-infrared absorbing agent, and the resin layer contains at least one selected from the group consisting of norbornene-based resin, polyimide-based resin, and polyether resin.

By having the resin layer, an optical filter having high transparency at a wavelength of 430 nm to 580 nm, high heat resistance, hard to warp, hard to break, and low in-plane retardation R ₀ can be obtained. Therefore, the solid-state imaging device including the optical filter having the resin layer has high image quality and can be easily manufactured.

In order for the solid-state imaging device to have high sensitivity, the average value of the transmittance of the resin layer at wavelengths of 430 nm to 580 nm is preferably 70% or more when the thickness is 1 μm.

The glass transition temperature of the resin layer is preferably 140° C. or higher because a solid-state imaging device can be manufactured by a low-temperature reflow step.

From the viewpoint of obtaining an optical filter that is difficult to warp, the Young's modulus of the resin layer is preferably 2 GPa or more.

The in-plane retardation R ₀ of the resin layer is preferably 50 nm or less, more preferably 20 nm or less, still more preferably 10 nm or less, and particularly preferably 5 nm or less. Regarding an optical filter with a small in-plane retardation R ₀ , when an imaging element having different sensitivities according to polarized light is provided, the polarized light characteristic can be accurately detected, and the error is reduced.

The resin layer in the base material may be one layer or multiple layers, and the base material may be Contains only the resin layer.

The thickness of the base material can be appropriately selected according to the intended use, and is not particularly limited, but the upper limit is preferably 250 μm or less, more preferably 200 μm or less, further preferably 150 μm or less, and the lower limit is preferably 30 μm or more, more preferably 40 μm above. When the thickness is within the above range, a sufficiently thin solid-state imaging element can be obtained with less warpage of the optical filter.

<Manufacturing method of resin layer>

The resin layer can be formed by, for example, melt molding or casting molding, and can be produced by a method of applying a coating agent such as an antireflection agent, a hard coat agent, and/or an antistatic agent after molding as necessary.

(A) Melt forming

The resin layer can be a method of melt-molding a pellet obtained by melt-kneading a resin and a near-infrared absorbent; a method of melt-molding a resin composition containing a resin and a near-infrared absorbent; It is manufactured by the method of melt-molding the pellet obtained by removing the solvent from the resin composition of the agent, the resin and the solvent, and the like. As a melt-molding method, injection molding, melt extrusion molding, blow molding, etc. are mentioned, for example.

(B) Casting

The resin layer can also remove the solvent by casting the resin composition containing the near-infrared absorber, the resin and the solvent on a suitable support; the anti-reflection agent, the hard coat agent and/or the antistatic agent will be included. A method of casting a resin composition such as a coating agent, a near-infrared absorber, and a resin on a suitable support; or a method containing an anti-reflection agent It is produced by a method of casting, curing, and drying a curable composition of a coating agent such as an agent, a hard coat agent and/or an antistatic agent, a pigment compound, and a resin on an appropriate support.

The support is not particularly limited, and supports made of glass, tempered glass, special glass, or resin exemplified as the material of the base material can be used, and supports other than the material of the base material can also be used , such as steel belts, steel drums, etc.

In the case where the base material is a base material including a resin substrate, the base material can be obtained by peeling the coating film from the support after casting, and the base material is obtained by laminating the support 11 on the support 11 . In the case of the base material of the resin layer 12, the base material can be obtained by not peeling off the coating film after casting.

The residual solvent amount in the resin layer obtained by the method is preferably as small as possible, and is usually 3 mass % or less, preferably 1 mass % or less, and more preferably 0.5 mass % or less with respect to the weight of the resin layer. When the residual solvent amount is within the above-mentioned range, the deformation of the optical filter and the change in optical properties are less likely to occur, and a resin layer that can easily exhibit a desired function can be obtained.

[Near infrared absorber]

The near-infrared absorbing agent preferably has a wavelength of 751 nm to 950 nm, more preferably 760 nm to 940 nm, further preferably 770 nm to 930 nm, and particularly preferably 775 nm to 925 nm. The wavelength has the maximum absorption wavelength. By making the absorption maximum wavelength within the above-mentioned range, the amount of light taken in by the solid-state imaging element can be adjusted within the wavelength range of 700 nm to 750 nm, and the entry of light in the wavelength range of 751 nm or more, which is low in human visual sensitivity, can be reduced. The amount of solid-state imaging elements can make the solid-state imaging device closer to human viewing sensitivity.

Examples of the near-infrared absorbing agent include cyanine-based dyes, phthalocyanine-based dyes, dithiol-based dyes, diimmonium-based dyes, squaraine-based dyes, ketonium-based dyes, and copper phosphates. . The structures of these dyes are not particularly limited, and generally known ones or commercially available products can be used as long as the effects of the present invention are not impaired. Moreover, as long as the effect of this invention is not impaired, the near-infrared absorber added to an optical filter may be 1 type or a plurality of types may be sufficient as it.

The near-infrared absorber is preferably contained in a range of 0.01 mass % to 60.0 mass % with respect to the resin layer. When the content of the near-infrared absorber is within the above range, suitable optical properties can be easily obtained. When the content exceeds 60.0 mass %, the properties such as high transparency, high heat resistance, resistance to warpage, and resistance to breakage are lost, which is a factor that reduces the image quality of the solid-state imaging device and increases the difficulty in manufacturing.

In addition, the near-infrared absorber preferably satisfies the following conditions (a) and (b).

(a)(absorbance λ ₇₀₀ )/(absorbance λ _max )≦0.1

(b) (absorbance λ ₇₅₁ )/(absorbance λ _max )≧0.1

Here, let the absorbance of the near-infrared absorber at a wavelength of 700 nm be “absorbance λ ₇₀₀ ”, the absorbance at a wavelength of 751 nm to be “absorbance λ ₇₅₁ ”, and the absorbance at the maximum absorption wavelength to be “absorbance λ 751 ” _max ”, the absorbance λ at the wavelength λ is calculated from the transmittance λ at the wavelength λ according to the following formula generally used.

Absorbance λ=-Log (internal transmittance λ)

For example, when the internal transmittance λ is 0.1 (10%), the absorbance is 1.0. The internal transmittance refers to a value obtained by excluding the surface reflectance from the obtained transmittance, and is obtained by dividing the obtained transmittance by the transmittance of the medium excluding the near-infrared absorber.

If the above-mentioned conditions (a) and (b) are satisfied, the transmittance of the wavelengths 700 nm to 750 nm required for sensing is high, and an optical filter that sufficiently shields the wavelengths that are not required for either the visual sensitivity or the sensing can be obtained. . Moreover, in order to sense the required high transmittance of the wavelength of 700nm~750nm and maintain the necessary condition (C), the absorbance _λ700 of the optical filter is preferably 0.25 or less, more preferably 0.2 or less, and more preferably 0.18 or less, especially Preferably, it is 0.16 or less. The lower limit of the absorbance λ ₇₀₀ of the optical filter is zero. By using the near-infrared absorber that satisfies the above-mentioned condition (a), the absorbance λ ₇₀₀ of the optical filter can be set within the above-mentioned range.

In addition, in order to achieve the necessary condition (D) in order to sufficiently shield long-wavelength light at 751 nm, which is not required for either self-viewing sensitivity or sensing, the absorbance λ ₇₅₁ of the optical filter is preferably 0.2 or more, more preferably 0.21 or more. , more preferably 0.23 or more, particularly preferably 0.25 or more. In addition, the absorbance λ ₇₅₁ of the optical filter is preferably 0.8 or less, more preferably 0.6 or less, and still more preferably 0.5 or less. By using the near-infrared absorber that satisfies the above-mentioned condition (b), the absorbance λ ₇₅₁ of the optical filter can be set within the above-mentioned range.

However, the near-infrared absorber satisfying the condition (b) tends to decrease (absorbance λ ₇₅₁ )/(absorbance λ _max ) as the absorption maximum wavelength λ _max changes from 751 nm to 950 nm. Therefore, it is necessary to increase the concentration of the near-infrared absorbing agent contained in the base material as the absorption maximum wavelength (λ _max ) changes from 751 nm to a long wavelength of 950 nm. On the other hand, when the near-infrared absorber satisfying the condition (a) is excessively contained in the base material, it may be difficult for the optical filter to maintain the required condition (C). Therefore, the near-infrared absorber contained in the base material preferably satisfies the following condition (c).

(c)1.5≧Σ _dye(n) [((950-shortest absorption maximum wavelength)×dye concentration×dye medium thickness)]>0.2

Here, "_{dye(n)" in "Σ dye(n)} " refers to each near-infrared absorber contained in the base material. In addition, the "shortest absorption maximum wavelength" refers to the shortest wavelength (nm) among the absorption maximum wavelengths at wavelengths of 751 nm to 950 nm, and the "dye concentration" refers to the concentration (mass %) of the near-infrared absorber contained in the base material. ), the so-called "dye medium thickness" refers to the thickness (mm) of the base material containing the near-infrared absorber.

By using the near-infrared absorber that satisfies the above-mentioned conditions (a) and (b) at the concentration of the above-mentioned condition (c), the absorbance λ ₇₀₀ and the absorbance λ ₇₅₁ of the optical filter can be set to the above-mentioned preferable range. , it is easy to satisfy the necessary conditions (C) and (D).

<Cyanine pigment>

The cyanine-based dye is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include Japanese Patent Laid-Open No. 2009-108267, Japanese Patent Laid-Open No. 2010-72575, and Japanese Patent Laid-Open No. 2016. - The cyanine-based dye described in Gazette No. 060774.

Some cyanine pigments also include those that do not have the maximum absorption wavelength at the wavelength of 751 nm to 950 nm, but are selected to have the maximum absorption wavelength at the wavelength of 751 nm to 950 nm. Large-wavelength cyanine pigments, or used in combination with cyanine pigments that do not have the maximum absorption wavelength at wavelengths of 751 nm to 950 nm and cyanine pigments with maximum absorption wavelengths at wavelengths of 751 nm to 950 nm, or used in combination with wavelengths of 751 nm to 950 nm. The dye other than the cyanine-based dye having the absorption maximum wavelength and the cyanine-based dye having the absorption maximum wavelength at a wavelength of 751 nm to 950 nm can be used as a near-infrared absorber for obtaining the effect of the present invention.

<Phthalocyanine dye>

The phthalocyanine-based dye is not particularly limited as long as the effects of the present invention are not impaired, and examples thereof include Japanese Patent Laid-Open No. 60-224589, Japanese Patent Application Laid-Open No. 1005-537319, and Japanese Patent Laid-Open No. Japanese Patent Laid-Open No. 4-23868, Japanese Patent Laid-Open No. 4-39361, Japanese Patent Laid-Open No. 5-78364, Japanese Patent Laid-Open No. 5-222047, Japanese Patent Laid-Open No. 5-222301, Japanese Patent Laid-Open No. 5-222301 Japanese Patent Laid-Open No. 5-222302, Japanese Patent Laid-Open No. 5-345861, Japanese Patent Laid-Open No. 6-25548, Japanese Patent Laid-Open No. 6-107663, Japanese Patent Laid-Open No. 6-192584, Japanese Patent Laid-Open No. 6-192584 Japanese Patent Laid-Open No. 6-228533, Japanese Patent Laid-Open No. 7-118551, Japanese Patent Laid-Open No. 7-118552, Japanese Patent Laid-Open No. 8-120186, Japanese Patent Laid-Open No. 8-225751, Japanese Patent Laid-Open No. 8-225751 Japanese Patent Laid-Open No. 9-202860, Japanese Patent Laid-Open No. 10-120927, Japanese Patent Laid-Open No. 10-182995, Japanese Patent Laid-Open No. 11-35838, Japanese Patent Laid-Open No. 2000-26748, Japanese Patent Laid-Open No. 2000-26748 Japanese Patent Laid-Open No. 2000-63691, Japanese Patent Laid-Open No. 2001-106689, Japanese Patent Laid-Open No. 2004-18561, Japanese JP 2005-220060 A Compounds described in etc.

Some of the phthalocyanine dyes also include those that do not have the maximum absorption wavelength at the wavelength of 751 nm to 950 nm, but the phthalocyanine dyes that have the maximum absorption wavelength at the wavelength of 751 nm to 950 nm are selected, or they are used in combination with the wavelengths of 751 nm to 950 nm without the maximum absorption wavelength. Phthalocyanine-based dyes and phthalocyanine-based dyes with maximum absorption wavelengths at wavelengths of 751 nm to 950 nm, or used in combination with phthalocyanine-based dyes without maximum absorption wavelengths at wavelengths of 751 nm to 950 nm and phthalocyanines with maximum absorption wavelengths at wavelengths of 751 nm to 950 nm A dye other than the dye can be used as a near-infrared absorber for obtaining the effect of the present invention. Many phthalocyanine-based dyes have steep absorption characteristics in the vicinity of the absorption maximum wavelength, and when a phthalocyanine-based dye is used in the optical filter of the present invention, it is preferable to use together with at least one other near-infrared absorbing agent.

<Dithiol-based dye>

The dithiol-based dye is not particularly limited as long as the effects of the present invention are not impaired, and examples thereof include the dithiol-based dyes described in Japanese Patent Laid-Open No. 2006-215395 and WO2008/086931.

Some of the dithiol-based dyes also include those that do not have the maximum absorption wavelength at the wavelength of 751 nm to 950 nm, but the dithiol-based dyes with the maximum absorption wavelength at the wavelength of 751 nm to 950 nm are selected, or they are used in combination with the wavelength of 751 nm to 950 nm. Dithiol-based dyes with wavelengths and dithiol-based dyes with the maximum absorption wavelength at wavelengths of 751nm to 950nm, or used in combination with wavelengths of 751nm to 950nm. Dyes other than the dithiol-based dye having an absorption maximum wavelength and the dithiol-based dye having an absorption maximum wavelength at wavelengths of 751 nm to 950 nm can be used as a near-infrared absorber for obtaining the effects of the present invention.

In addition, for example, as described in WO1998/034988, a counter-ion-bonded body of a dithiol-based dye can also be used.

<Squaric acid ylide pigment>

The squaraine-based dye is not particularly limited as long as the effects of the present invention are not impaired, and examples thereof include the squaraine-based dyes represented by the following formulae (4) to (6), Japanese Patent The squaraine-based dyes and the like described in Laid-Open Publication No. 2014-074002 and Japanese Patent Laid-Open No. 2014-052431 may be synthesized by a generally known method.

[hua 5]

In the above formulae (4) to (6), X independently represents an oxygen atom, a sulfur atom, a selenium atom or -NH-, and the R ¹ and R ^1' are preferably a hydrogen atom, a chlorine atom, and a chlorine atom respectively independently. atom, fluorine atom, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, cyclohexyl, phenyl, hydroxyl, amino, dimethylamine, The nitro group is more preferably a hydrogen atom, a chlorine atom, a fluorine atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and a hydroxyl group. R ² to R ⁸ each independently represent a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, a -L ¹ or -NR ^{g Rh} group. R ^g and R ^h each independently represent a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d , -L ^e , -L ^f , -L ^g , -L ^h or -C(O)R ⁱ group (R ⁱ represents -L ^a , -L ^b , -L ^c , -L ^d or -L ^e ), R ⁹ independently represents a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d , -L ^e , -L ^f , -L ^g or -L ^h .

L ¹ is L ^a , L ^b , L ^c , L ^d , ^Le , L ^f , L ^g or L ^h .

The L ^a to L ^h represent the following groups.

(L ^a ) the aliphatic hydrocarbon group having 1 to 12 carbon atoms which may have a substituent L

(L ^b ) the halogen-substituted alkyl group having 1 to 12 carbon atoms which may have a substituent L

(L ^c ) the alicyclic hydrocarbon group having 3 to 14 carbon atoms which may have a substituent L

(L ^d ) the aromatic hydrocarbon group having 6 to 14 carbon atoms which may have a substituent L

(L ^e ) the heterocyclic group having 3 to 14 carbon atoms which may have a substituent L

(L ^f ) the alkoxy group having 1 to 12 carbon atoms which may have a substituent L

(L ^g ) the acyl group having 1 to 12 carbon atoms which may have a substituent L

(L ^h ) the alkoxycarbonyl group having 1 to 12 carbon atoms which may have the substituent L

(L ⁱ ) the thioether group or disulfide group having 1 to 12 carbon atoms which may have the substituent L

R ⁹ independently represents a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d or -L ^e .

The compound (5) can adjust the absorption maximum wavelength by a substituent, and the X is preferably a sulfur atom from the viewpoint of easily becoming a compound having a maximum absorption wavelength of 751 nm to 950 nm.

Some of the squaraine ylide pigments also include those that do not have the maximum absorption wavelength at the wavelength of 751 nm to 950 nm, but are selected to have the wavelength of 751 nm to 950 nm. The squaraine-based dye with the maximum absorption wavelength, or the squaraine-based dye with no absorption maximum wavelength at the wavelength of 751nm~950nm and the squaraine-based dye with the maximum absorption wavelength at the wavelength of 751nm~950nm, or used together Pigments other than squaraine-based dyes having no maximum absorption wavelength at wavelengths of 751 nm to 950 nm and dyes other than squaraine-based dyes having maximum absorption wavelengths at wavelengths of 751 nm to 950 nm can be used as near-infrared absorbers for obtaining the effects of the present invention use.

<Diimmonium pigment>

The diimmonium-based dye is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include diimmonium-based dyes represented by the following formula (7-1) or (7-2), Japanese The diimmonium-based dyes and the like described in Patent No. 4168031, Japanese Patent No. 4252961, Japanese Patent Laid-Open No. 63-165392, WO2004/048480, etc. may be synthesized by a generally known method.

[hua 7]

In formulas (7-1) and (7-2), Rdi1 to Rdi12 each independently represent a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a phosphoric acid group, a -SR ⁱ group, and -SO ₂ R ⁱ group, -OSO ₂ R ⁱ group or any one of the following L ^a to L ^h , R ^g and R ^h each independently represent a hydrogen atom, a -C(O)R ⁱ group or the following L ^a to L h Any one of ^Le , R ⁱ represents any one of the following L ^a to L ^e , (L ^a ) an aliphatic hydrocarbon group having 1 to 12 carbon atoms

(L ^b ) a halogen-substituted alkyl group having 1 to 12 carbon atoms

(L ^c ) Alicyclic hydrocarbon group having 3 to 14 carbon atoms

(L ^d ) Aromatic hydrocarbon group with 6 to 14 carbon atoms

(L ^e ) Heterocyclic group with 3 to 14 carbon atoms

(L ^f ) alkoxy group having 1 to 12 carbon atoms

(L ^g ) an acyl group having 1 to 12 carbon atoms that may have a substituent L, (L ^h ) an alkoxycarbonyl group having 1 to 12 carbon atoms that may have a substituent L

Substituent L is selected from the group consisting of aliphatic hydrocarbon groups having 1 to 12 carbon atoms, halogen-substituted alkyl groups having 1 to 12 carbon atoms, alicyclic hydrocarbon groups having 3 to 14 carbon atoms, aromatic hydrocarbon groups having 6 to 14 carbon atoms, and aromatic hydrocarbon groups having 6 to 14 carbon atoms. At least one of the groups consisting of 3-14 heterocyclic groups, adjacent Rdi1 and Rdi2, Rdi3 and Rdi4, Rdi5 and Rdi6, and Rdi7 and Rdi8 can also form a ring that can have a substituent L, and X represents neutralization Anion required for charge.

Described Rdi1～Rdi8 is preferably selected from hydrogen atom, methyl, ethyl, n-propyl, isopropyl, n-butyl, second butyl, tertiary butyl, cyclohexyl, phenyl, benzyl , more preferably a group selected from isopropyl, sec-butyl, tert-butyl and benzyl.

Described Rdi9～Rdi12 is preferably selected from hydrogen atom, chlorine atom, fluorine atom, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, cyclohexyl, Phenyl, hydroxyl, amino, dimethylamino, cyano, nitro, methoxy, ethoxy, n-propoxy, n-butoxy, acetylamino, propionylamino, N-A Acetylamino, trifluoroformylamino, pentafluoroacetylamino, tertiary butylamino, cyclohexynylamino, n-butylsulfonyl, methylthio, ethyl group in thio, n-propylthio, n-butylthio, more preferably selected from chlorine atom, fluorine atom, methyl group, ethyl group, n-propyl group, isopropyl group, tert-butyl group, hydroxyl group , dimethylamino, methoxy, ethoxy, acetylamino, propionylamino, trifluoromethylamino, pentafluoroacetylamino, tertiary butylamino, ring The group in the hexynylamino group is particularly preferably a group selected from the group consisting of methyl, ethyl, n-propyl, and isopropyl.

The X ^- is an anion required to neutralize the charge, as in formula (7-2), an ion is required in the case of divalent anion, as in formula (7-1), in the case of monovalent anion two ions are required. In the latter case, the two anions X ^- may be the same or different, but from the viewpoint of synthesis, they are preferably the same. X ^- or X ^2- is not particularly limited as long as it is the anion.

In the near-infrared absorber, in terms of the level of visible light transmittance, the absorption characteristics in the range of wavelength 700nm-750nm, and the shielding performance in the range of wavelength 800nm-1100nm, formula (4), formula (5) are preferred. , compounds represented by formula (7-1) and formula (7-2).

[Near infrared reflective film]

The near-infrared reflective film that can be used in the present invention is a film having the ability to reflect near-infrared rays. Examples of the near-infrared reflective film include a vapor-deposited aluminum film, a precious metal thin film, a resin film in which metal oxide fine particles containing indium oxide as a main component and a small amount of tin oxide are dispersed, or a high-refractive-index material layer and a low-refractive-index material layer alternately laminated. Dielectric multilayer films of refractive index material layers, etc. If the near-infrared reflective film is provided, more Effectively cut off near infrared rays.

In the present invention, the near-infrared reflective film may be provided on one side of the base material, or may be provided on both sides. When provided on one side, it is excellent in manufacturing cost and manufacturing easiness, and when provided on both sides, the optical filter which has high intensity|strength and is hard to generate|occur|produce a warp can be obtained.

In the near-infrared reflective film, in terms of less scattering, good adhesion, high transmission characteristics of visible light in the wavelength range of 430 nm to 580 nm, and high shielding performance of light in the wavelength range of 800 nm to 1100 nm, it is preferable to alternately A dielectric multilayer film in which a high-refractive-index material layer and a low-refractive-index material layer are laminated. When the near-infrared reflective film is a dielectric multilayer film, the image quality of the obtained solid-state imaging device can be improved.

<Dielectric multilayer film>

As the material constituting the high refractive index material layer, a material having a refractive index of 1.7 or more can be used, and a material having a refractive index in the range of usually 1.7 to 2.5 is selected. As the material, for example, titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, or indium oxide, etc. as the main component, and a small amount (for example, relative to the main component) can be mentioned. 0% to 10%) titanium oxide, tin oxide and/or cerium oxide and other materials.

As the material constituting the low-refractive-index material layer, a material having a refractive index of less than 1.7 can be used, and a material whose refractive index is usually in the range of 1.2 or more and less than 1.7 is selected. Examples of the material include resins, silica, alumina, lanthanum fluoride, magnesium fluoride, and sodium aluminum hexafluoride, and mixtures thereof such that the refractive index of the material is less than 1.7 The way to set the drainer etc.

The method of laminating the high-refractive-index material layer and the low-refractive-index material layer is not particularly limited as long as a dielectric multilayer film in which these material layers are laminated is formed. For example, alternating layers can be formed directly on the substrate by CVD method, vacuum evaporation method, sputtering method, ion-assisted evaporation method, ion plating method, radical-assisted sputtering method, ion beam sputtering method, etc. A dielectric multilayer film composed of a refractive index material layer and a low refractive index material layer. Ion-assisted vapor deposition, ion-plating, and radical-assisted sputtering are preferred to obtain a high-quality film in which the optical film thickness of the obtained multilayer film is not easily changed with the environment. Regarding the ion-assisted vapor deposition method, the resulting optical filter has less warpage and is more preferable.

Regarding the thickness of each of the high-refractive-index material layers and the low-refractive-index material layers, generally if the near-infrared wavelength to be shielded is λ (nm), the thickness of each layer except for the two layers adjacent to the base material and the outermost layer is relatively large. The optical thickness of 0.1λ~0.5λ is preferable. If the optical thickness is within this range, the product (n×d) of the refractive index (n) and the film thickness (d) becomes the difference between the optical film thickness calculated by λ/4 and the high-refractive-index material layer and the low-refractive-index material layer. When the thickness of each layer is approximately the same value, depending on the relationship between the optical properties of reflection and refraction, the shielding and transmission of specific wavelengths tend to be easily controlled. The two layers adjacent to the base material preferably have a physical thickness of 5 nm to 45 nm or less. In addition, the outermost layer preferably has an optical thickness of 0.05λ to 0.2λ. When the thickness of the two layers adjacent to the base material and the outermost layer are in the above-mentioned range, the reflectance of visible light can be reduced, and by meeting the above-mentioned requirement (Z), ghost images can be reduced.

In addition, the total number of laminated layers of the high-refractive-index material layer and the low-refractive-index material layer in the dielectric multilayer film is preferably 5 to 60 layers, more preferably 10 to 50 layers.

Furthermore, when the substrate is warped during the formation of the dielectric multilayer film, it is In order to eliminate warpage, a method of forming a dielectric multilayer film on both surfaces of the base material, or irradiating electromagnetic waves such as ultraviolet rays to the surface of the base material on which the dielectric multilayer film is formed can be employed. Furthermore, in the case of irradiating electromagnetic waves, the irradiation may be performed during the formation of the dielectric multilayer film, or may be separately irradiated after the formation.

However, in the conventional design methods described in Patent Document 1 and Patent Document 2, in the case of forming a dielectric multilayer film for shielding wavelengths of 751 nm to 1200 nm, the transmittance at wavelengths of 700 nm to 750 nm required for sensing is obtained. There is also a risk of decline. Therefore, in order to obtain an optical filter satisfying the requirement (C) and the requirement (Z2), the dielectric multilayer film is preferably designed to satisfy the following requirement (e).

(e) The layers other than the two layers adjacent to the base material and the outermost layer do not include a layer with an optical film thickness of 205 nm or less (hereinafter also referred to as "layer (e1)").

Here, the optical film thickness represents the physical quantity of physical film thickness×refractive index, and the refractive index is the refractive index at a wavelength of 550 nm.

In a dielectric multilayer film in which layers having different refractive indices are laminated, it is designed to shield wavelengths around the optical film thickness × 4. Since the two layers adjacent to the base material and the layers other than the outermost layer adjacent to the output medium are layers that contribute to the formation of a shielding layer that reduces transmittance, in order to satisfy the requirement (C), it is preferable not to include the above layer (e1).

In order to satisfy the necessary condition (Z2), it is preferable that the dielectric multilayer films formed on both sides of the base material satisfy the condition (e). Thereby, an optical filter with high transmittance at wavelengths of 700 nm to 750 nm required for sensing and shielding wavelengths of 751 nm to 1200 nm is obtained. The optical film thickness of the layer (e1) under the condition (e) is preferably 210 nm or less, more preferably 215 nm or less.

In addition, in order to satisfy the necessary condition (Z1), the dielectric multilayer film is preferably designed to satisfy the following condition (f).

(f) In the two layers adjacent to the base material and the layers other than the outermost layer, the standard deviation of the optical film thickness is 6 nm to 20 nm.

By designing the dielectric multilayer film that satisfies the condition (f), the transmittance when measured from the direction perpendicular to the surface of the optical filter in the necessary condition (B) "in the wavelength range of 800 nm to 1000 nm" The average value of the ratio is 10% or less" and the characteristics of the necessary condition (Z1) can be easily combined. When the optical filter has a dielectric multilayer film on both sides of the base material, it is more preferable that the dielectric multilayer films on both sides satisfy the condition (f). The standard deviation of the optical film thickness under the condition (f) is preferably 6 nm to 18 nm, more preferably 6 nm to 16 nm.

[Near UV Absorber]

The near-ultraviolet absorber that can be used in the present invention is preferably selected from azomethine-based compounds, indole-based compounds, benzotriazole-based compounds, triazine-based compounds, merophthalocyanine-based compounds, oxazole-based compounds, At least one of the group consisting of naphthyl imide-based compounds, oxadiazole-based compounds, oxazine-based compounds, oxazolidine-based compounds, and anthracene-based compounds, preferably having at least one absorption at a wavelength of 300 nm to 420 nm maximum. By containing the near-ultraviolet absorber in addition to the near-infrared absorber, an optical filter having a small incident angle dependence also in the near-ultraviolet wavelength region can be obtained.

(A) Azomethine-based compound

The azomethine-based compound is not particularly limited, for example, it can be represented by the following formula (8) indicated.

In the formula (8), R ^a1 to R ^a5 each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, an alkyl group having 1 to 15 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, or an alkoxy group having 1 to 9 carbon atoms. Alkoxycarbonyl.

(B) Indole-based compound

The indole-based compound is not particularly limited, and can be represented by, for example, the following formula (9).

In formula (9), R ^b1 to R ^b5 each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, a cyano group, a phenyl group, an aralkyl group, an alkyl group having 1 to 9 carbon atoms, and an alkyl group having 1 to 9 carbon atoms. An alkoxy group or an alkoxycarbonyl group having 1 to 9 carbon atoms.

(C) Benzotriazole-based compound

The benzotriazole-based compound is not particularly limited, and can be represented by the following formula (10), for example.

In formula (10), R ^c1 to R ^c3 each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an aralkyl group, an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, or a substituted An alkyl group having 1 to 9 carbon atoms in an alkoxycarbonyl group having 1 to 9 carbon atoms in the group.

(D) Triazine-based compound

The triazine-based compound is not particularly limited, and can be represented by, for example, the following formula (11), formula (12), or formula (13).

[Chemical 11]

[Chemical 13]

In formulas (11) to (13), R ^d1 independently represents a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, an alkenyl group having 3 to 8 carbon atoms, An aryl group having 6 to 18 carbon atoms, an alkylaryl group or an arylalkyl group having 7 to 18 carbon atoms. Wherein, these alkyl groups, cycloalkyl groups, alkenyl groups, aryl groups, alkylaryl groups and arylalkyl groups may be substituted by hydroxyl groups, halogen atoms, alkyl groups with 1 to 12 carbon atoms or alkoxy groups, or Interrupted by an oxygen atom, a sulfur atom, a carbonyl group, an ester group, an amide group or an imino group. Additionally, the substitutions and interruptions may be combined. R ^d2 to R ^d9 each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 15 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, an alkenyl group having 3 to 8 carbon atoms, a carbon atom An aryl group having 6 to 18 carbon atoms, an alkylaryl group having 7 to 18 carbon atoms, or an arylalkyl group.

(E) Commercially available products

Examples include: "S0511" manufactured by Few Chemicals, "Lumogen (registered trademark) Fviolet 570" manufactured by BASF, "Uvitex (Uvitex) registered trademark) OB", Showa "Hakkol RF-K" manufactured by Chemical Industry Co., Ltd., "Nikkafluor EFS" and "Nikkafluor SB-conc" manufactured by Nippon Chemical Industry Co., Ltd. Wait. Also available are "ABS407" manufactured by Exiton, "UV 381A", "UV 381B", "UV 382A", "UV 386A" manufactured by QCR Solutions Corp., BASF Corporation "TINUVIN 326", "TINUVIN 460", "TINUVIN 479", and "BONASORB" manufactured by Orient Chemical Co., Ltd. )UA3911" etc.

<Other ingredients>

The resin layer may further contain additives such as antioxidants, dispersants, flame retardants, plasticizers, thermal stabilizers, light stabilizers, and metal complex compounds within a range that does not impair the effects of the present invention. Moreover, when manufacturing a resin-made base material by the said casting molding, manufacture of a resin-made base material can be made easy by adding a leveling agent or an antifoamer. These other components may be used alone or in combination of two or more.

As the antioxidant, for example, 2,6-di-tert-butyl-4-methylphenol, 2,2'-dioxy-3,3'-di-tert-butyl-5, 5'-dimethyldiphenylmethane, and tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane, 1,3,5- Tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazinyl-2,4,6(1H,3H,5H)-trione and the like. In addition, these additives may be mixed with resin etc. at the time of manufacture of a resin base material, and may be added at the time of resin manufacture. In addition, the amount of addition is appropriately selected according to the desired properties, and is usually 0.01 to 5.0 parts by mass relative to 100 parts by mass of the resin, It is preferably 0.05 to 2.0 parts by mass.

[Other functional films]

In the optical filter of the present invention, a functional film can be appropriately provided within a range that does not impair the effects of the present invention.

The optical filter of the present invention may include one layer composed of a functional film, or may include two or more layers. When the optical filter of this invention contains the layer which consists of two or more layers of functional films, it may contain two or more layers of the same layer, and may contain two or more layers of different layers.

The method of laminating the functional film is not particularly limited, and examples thereof include a method of melt-molding or casting-molding coating agents such as antireflection agents, hard coat agents, and/or antistatic agents on a substrate or a near-infrared reflective film.

Moreover, the said coating agent can also be manufactured by apply|coating a curable composition on a base material or a near-infrared reflective film by a bar coater etc., and hardening by ultraviolet irradiation and/or heating, etc.. From the viewpoint of improving the breaking strength of the obtained base material, being less prone to damage, and reducing warpage, a functional film having a curable composition is preferred.

Examples of the curable composition include ultraviolet (UV)/electron beam (EB) curable resins, thermosetting resins, and the like, and specific examples thereof include vinyl compounds, urethanes, and amine groups. Formate acrylate-based, acrylate-based, epoxy-based and epoxy-acrylate-based resins, etc. Examples of the curable composition containing these coating agents include vinyl-based, urethane-based, urethane-acrylate-based, acrylate-based, epoxy-based, and epoxy-acrylate-based Curable composition, etc.

As the urethane-based or urethane-acrylate-based hardening The components contained in the composition include, for example, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, bis(2-hydroxyethyl)isocyanurate di(2-hydroxyethyl)isocyanurate (Meth)acrylates and oligomeric urethane (meth)acrylates having two or more (meth)acryloyl groups in the molecule. These components may be used alone or in combination of two or more. Furthermore, oligomers or polymers, such as polyurethane (meth)acrylate, or oligomers or polymers, such as polyester (meth)acrylate, can also be prepared.

Examples of the vinyl compounds include vinyl acetate, vinyl propionate, divinylbenzene, ethylene glycol divinyl ether, diethylene glycol divinyl ether, and triethylene glycol divinyl ether. etc., but are not limited to these examples. These components may be used alone or in combination of two or more.

The components contained in the epoxy-based or epoxy-acrylate-based curable composition are not particularly limited, and examples thereof include glycidyl (meth)acrylate, methyl glycidyl (meth)acrylate, and glycidyl (meth)acrylate. Oligomeric epoxy (meth)acrylates etc. which have two or more (meth)acryloyl groups in a molecule|numerator. These components may be used alone or in combination of two or more. Furthermore, oligomers or polymers, such as polyepoxy (meth)acrylate, can also be prepared.

Commercially available products of the curable composition include "LCH" and "LAS" manufactured by Toyo Ink Co., Ltd.; "Beam Collection" manufactured by Arakawa Chemical Industry Co., Ltd.; Daicel Cytec ) (stock) "EBECRYL (EBECRYL)", "UVACURE (UVACURE)"; Desolite)Z" and so on.

In addition, the curable composition may contain a polymerization initiator. as the As the polymerization initiator, a known photopolymerization initiator or thermal polymerization initiator may be used, or a photopolymerization initiator and a thermal polymerization initiator may be used in combination. A polymerization initiator may be used individually by 1 type, and may use 2 or more types together.

In the curable composition, when the total amount of the curable composition is 100% by mass, the blending ratio of the polymerization initiator is preferably 0.1% by mass to 10% by mass, more preferably 0.5% by mass ~10% by mass, more preferably 1% by mass to 5% by mass. When the mixing ratio of the polymerization initiator is within the above range, the curable composition is excellent in curing properties and handleability, and functional films such as an antireflection film, a hard coat film, or an antistatic film having desired hardness can be obtained.

Furthermore, an organic solvent can be added as a solvent to the said curable composition, and a well-known solvent can be used as an organic solvent. Specific examples of the organic solvent include alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ethyl acetate Ester, butyl acetate, ethyl lactate, γ-butyrolactone, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate and other esters; ethylene glycol monomethyl ether, diethylene glycol monobutyl ether and other ethers Aromatic hydrocarbons such as benzene, toluene and xylene; amides such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone. These solvents may be used alone or in combination of two or more.

The thickness of the functional film is preferably 0.1 μm to 20 μm, more preferably 0.5 μm to 10 μm, and particularly preferably 0.7 μm to 5 μm.

In addition, in order to improve the adhesiveness between the base material and the functional film and/or the near-infrared reflective film, or the adhesiveness between the functional film and the near-infrared reflective film, the surface of the base material or the functional film may be subjected to corona treatment or plasma treatment. and other surface treatment.

The material is sometimes used as a material for a low-pass filter or wavelength plate for reducing moiré or false color in imaging devices such as digital still cameras, digital video cameras, surveillance cameras, in-vehicle cameras, network cameras, and drones.

[Use of Optical Filters]

The optical filter of the present invention has the characteristics of wide viewing angle, high red sensitivity, and improved ghosting. Therefore, it is useful for viewing sensitivity correction of solid-state imaging elements such as CCDs and CMOSs of camera modules. Especially for digital still cameras, mobile phone cameras, digital video cameras, PC cameras, surveillance cameras, automotive cameras, televisions, navigators, portable information terminals, personal computers, video game consoles, portable game consoles, It is useful in fingerprint authentication systems, distance measurement sensors, iris authentication systems, face authentication systems, distance measurement cameras, digital music players, and the like.

<Solid-state imaging device>

The solid-state imaging device of the present invention includes the optical filter of the present invention. Here, the solid-state imaging device is an image sensor including a solid-state imaging element such as a CCD or a CMOS. As a member constituting the solid-state imaging element, a photoelectric conversion element that converts light of a specific wavelength into electric charge, such as a silicon photodiode or an organic semiconductor, can be used. In addition, among the pixels constituting the solid-state imaging element, there are at least pixels having sensitivity to near-infrared rays having a wavelength of 700 nm to 750 nm.

In the solid-state imaging device of the present invention, a polarizer such as a retardation film or a wire grid may be provided on the entire surface of the solid-state imaging element. When the polarizing element is provided, the phase information of the image can be obtained, and the image and the shape of the subject can be measured three-dimensionally except for the reflected light of the subject, which is better.

<wire grid>

For the wire grid provided in the solid-state imaging element of the present invention, aluminum, nickel, silver, platinum, tungsten, or alloys containing these metals can be used, and it is preferable to provide Japanese Patent Laid-Open No. 2017-003878, Japanese Patent Laid-Open The polarizer described in Publication No. 2017-005111.

<Camera Module>

The camera module of the present invention includes the optical filter of the present invention. Here, the camera module is a device that includes an image sensor, a focus adjustment mechanism, a phase detection mechanism, a distance measurement mechanism, and the like, and outputs image and distance information as electrical signals. Here, the case where the optical filter of this invention is used for a camera module is demonstrated concretely. 9( a ) and 9( b ) are schematic cross-sectional views of the camera module 400 .

In the case of the optical filter 1 of the present invention, there is no large difference in the transmission wavelength between the light incident from the vertical direction and the transmission wavelength of the light incident from 30° with respect to the vertical direction of the filter 1 (the absorption (transmission) wavelength is incident). The angular dependence is small), so even if it is provided between the lens 301 and the sensor 302, the color change of the color of the entire sensor of the filter 1 is small. Therefore, when the optical filter 1 of the present invention is used in a camera module, a lens corresponding to a higher angle of incidence can be used, and the low profile of the camera module can be realized.

[ghosting]

In the present invention, the ghost that causes image quality degradation is that light reflected from the surface or back of an optical component between the subject and the imaging element is reflected by other components, etc., and is incident on the original imaging position (normal detection unit 304 ). ) different positions of the light of the imaging element The resulting image is bad.

As shown in FIG. 10 , when the light reflected by the surface of the optical filter 1 is further reflected by the lens, passes through the optical filter 1 and enters the sensor 302 , a ghost image 306 is generated. Alternatively, when the light reflected from the sensor 302 is further reflected on the back surface of the optical filter 1 and is incident on the sensor 302 , a ghost image 305 is generated.

Conventional optical filters have large reflections especially in the vicinity of wavelengths of 680 nm to 720 nm, causing ghosting. However, the optical filter 1 of the present invention has a reflectance of 10% or less on both surfaces at a wavelength of 700 nm, and the (Za) value of both surfaces is 730 nm or more, so the reflectance at a wavelength of 700 nm to (Za) nm is less than 50% . Therefore, the surface of the optical filter in the vicinity of wavelengths 680 nm to 720 nm has less reflection on both surfaces. Therefore, the occurrence of ghost images 305 and ghost images 306 erroneously incident on the sensor is reduced, and good image quality can be obtained.

FIG. 11 is an example of the light source 401 and the ghost image 402 .

[Example]

Hereinafter, the present invention will be described by way of examples, but the present invention is not limited by these examples at all. In addition, unless otherwise specified, "part" and "%" refer to "part by mass" and "% by mass".

The measurement methods and evaluation methods of various physical properties in the examples are as follows.

<Transmittance>

The transmittance was measured using a spectrophotometer "U-4100" manufactured by Hitachi High-technologies Co., Ltd. The transmittance when measured from a direction perpendicular to the surface of the substrate or the optical filter is measured as shown in FIG. 6 . Unpolarized light (detector 201 ) transmitted vertically through the optical filter. In addition, the transmittance when measured at an angle of 30° from the direction perpendicular to the surface of the optical filter was measured as shown in FIG. Polarized light rays, and calculated from the average of these.

In addition, the average value of transmittance at wavelengths A nm to B nm is obtained by measuring the transmittance of each wavelength at intervals of 1 nm from A nm to B nm, and dividing the total transmittance by the measured transmittance. Calculated from the value obtained by the number of ratios (wavelength range, B-A+1).

<Reflectivity>

Spectroscopic reflectance was measured by the absolute reflectance measurement method using a spectrophotometer "U-4100" manufactured by Hitachi High-technologies Co., Ltd. as shown in Fig. 8 for unpolarized light when incident at 5°. The intensity of light reflected from the front surface and the back surface incident on one surface of the optical filter and the intensity of light reflected from the front surface and the back surface incident from the other surface of the optical filter were measured.

In addition, the average value of the reflectance at wavelengths A nm to B nm is obtained by measuring the reflectance at each wavelength of A nm or more and B nm or less at every 1 nm, and dividing the total reflectance by the measured reflectance. Calculated from the value obtained by the number of ratios (wavelength range, B-A+1).

<Evaluation of Absorbents>

Regarding the evaluation of absorbents, various absorbents were added to 100 parts by mass of norbornene resin "ARTON" (refractive index 1.52, glass transition temperature 160°C) manufactured by JSR Co., Ltd., Further, dichloromethane was added to obtain a solution having a solid content of 30% by mass. Next, the obtained solution was cast-molded on a smooth glass plate, dried at 50° C. for 8 hours, further dried at 100° C. under reduced pressure for 1 hour, and peeled off to obtain a base material with a thickness of 0.1 mm. The addition amount of each absorber was made into the density|concentration which makes the transmittance|permeability at the absorption maximum wavelength of the obtained base material 10%. From the transmittance of the obtained base material, the absorption maximum wavelength, the shortest absorption maximum wavelength, the absorbance λ ₇₀₀ , the absorbance λ ₇₅₁ , and the absolute value of the difference between (Aa) and (Ab) were calculated.

<Refractive Index>

The refractive index of each material in this specification is set to the value of wavelength 550nm unless it is specified.

<Glass transition temperature>

A differential scanning calorimeter "DSC6200" manufactured by Siino Technology Co., Ltd. was used, and the measurement was performed at a temperature increase rate: 20°C per minute and a nitrogen gas flow.

<In-plane phase difference R ₀ >

The phase difference at 550 nm of the base material obtained in the example was measured using a phase difference meter (“KOBRA-HBR” manufactured by Oji Measuring Instruments Co., Ltd.), and it was set as the in-plane phase difference R ₀ .

<Green sensitivity and near-infrared sensitivity evaluation>

Regarding the effect of the optical filter on the visible light sensitivity and the near-infrared sensitivity, as a numerical value for the evaluation of the imaging device corresponding to the configuration (band-pass filter 303 ) of FIG. 9( b ), incident from the surface of the optical filter in the vertical direction was used The transmittance T ₀ (λ) at different wavelengths at the time, and the transmittance T ₃₀ (λ) at different wavelengths incident at an angle of 30 degrees from the vertical direction, calculate the green color according to the following equations (i)~(v) pixel sensitivity and near-infrared pixel sensitivity.

G ₀ represents the sensitivity of the green pixel when sunlight is incident from the vertical direction of the optical filter. Specifically, based on Equation (i), as the transmittance T ₀ (λ) of the optical filter at different wavelengths, the sunlight ray Intensity I(λ) at different wavelengths, sensitivity G(λ) at different wavelengths of the green sensor pixel, and transmittance DT(λ) at different wavelengths through the filter in the dual wavelength region that transmits green and near-infrared The sum of the calculated values per 1 nm of the product is calculated.

IR ₀ represents the near-infrared pixel sensitivity when sunlight is incident from the vertical direction of the optical filter, and specifically, based on the equation (ii), as the transmittances T ₀ (λ) at different wavelengths of the optical filter, Intensity I(λ) at different wavelengths of sunlight, sensitivity IR(λ) at different wavelengths of near-infrared sensor pixels, and transmittance at different wavelengths through filters in the dual-wavelength region that transmits green and near-infrared rays Calculated as the sum of the calculated values per 1 nm of the product of DT(λ).

G ₃₀ represents the sensitivity of the green pixel when sunlight is incident at an angle of 30° from the vertical direction of the optical filter. Specifically, based on the equation (iii), as the transmittance T ₀ ( λ), the intensity I(λ) of different wavelengths of sunlight, the sensitivity G(λ) of different wavelengths of the green sensor pixel, and the transmission of different wavelengths through the filter in the dual-wavelength region that transmits green and near-infrared rays Calculated as the sum of the calculated values per 1 nm of the product of the rate DT(λ).

IR ₃₀ represents the near-infrared pixel sensitivity when sunlight enters the optical filter at an angle of 30° from the vertical direction of the optical filter, and specifically, based on the formula (iv), as the transmittance T of the optical filter at different wavelengths ₀ (λ), intensity I (λ) of different wavelengths of sunlight, sensitivity IR (λ) of different wavelengths of sensor pixels of near-infrared, and two-wavelength transmission filter that transmits green and near-infrared It is calculated as the sum of the calculated values per 1 nm of the products of the transmittances DT(λ) at different wavelengths.

G _N represents the amount of noise at wavelengths of 800 nm to 1200 nm in the green pixel, and specifically, based on the equation (v), the transmittance T 0 (λ) of the optical filter at different wavelengths, the transmittance T ₀ (λ) of the different wavelengths of sunlight, and the Product of intensity I(λ), sensitivity IR(λ) at different wavelengths of sensor pixels of near-infrared, and transmittance DT(λ) at different wavelengths through filter in the dual-wavelength region that transmits green and near-infrared The sum of the calculated values per 1 nm is calculated.

As shown in FIG. 3 , the intensity I(λ) of sunlight at different wavelengths was published by the National Research and Development Corporation for New Energy Industrial Technology Development Corporation, and the exposure data in Gifu on a certain date were normalized to a value with a maximum intensity of 1.0. Green and NIR The different wavelength sensitivity of each sensor pixel of the line is based on the description of Japanese Patent Laid-Open No. 2017-216678, and the values shown in FIG. 4 are used.

A two-wavelength transmission filter that transmits green and near-infrared rays is made of a glass substrate (D263 manufactured by SCHOTT, thickness 0.1 mm) on one surface using an ion-assisted vacuum evaporation device at an evaporation temperature of 120°C. , to form a dielectric multilayer of the design (0) shown in Table 2 [a layer of silicon dioxide (SiO ₂ : Refractive index 1.46 at 550 nm) and titanium dioxide (TiO ₂ : Refractive index 2.48 at 550 nm) layers alternately laminated] film obtained. The transmittance DT(λ) of different wavelengths of the two-wavelength region transmission filter is shown in FIG. 5 .

According to the obtained pixel sensitivity, an optical filter satisfying both the following requirements (Xa) and (Xb) has a small amount of change in sensitivity even at a high incident angle in a green pixel, and a wavelength of 800 nm at which the human visual sensitivity is low The amount of noise at ~1200 nm is small, and the green sensitivity is set to ○. An optical filter that does not satisfy both the requirements (Xa) and (Xb) is set to the green sensitivity x.

Necessary condition (Xa)0.8≦G ₃₀ /G ₀ ≦1.2

Necessary condition (Xb)G _N /G ₀ ≦0.05

In addition, an optical filter that satisfies both the following requirements (Y) and (Z) has a high near-infrared sensitivity for green pixel contrast and a small amount of change in near-infrared sensitivity even at a wide angle of view. Infrared sensitivity ○. In the case where the necessary condition (Y) is not satisfied, it is expected that IR ₀ needs to increase the sensor sensitivity by more than 5 times compared to G ₀ , and the amount of noise also increases by more than 5 times. In addition, when the necessary condition (Z) is not satisfied, in IR ₃₀ , the sensitivity of IR ₀ to 0.2 times changes. That is, when the necessary conditions (Y) and (Z) are not satisfied, it is difficult to shift the noise amount of the IR ₃₀ during sensing under the sunlight. Therefore, an optical filter that does not satisfy both the requirements (Y) and (Z) is set to near-infrared sensitivity x.

Required condition (Y) IR ₀ /G ₀ is 0.21 or more

Necessary condition (Z)0.8≦IR ₃₀ /IR ₀ ≦1.2

<Ghosting Evaluation>

An imaging device including the obtained optical filter was constructed between the lens and the sensor used in the imaging device ("KBCR-M04VG" manufactured by Shikino High Tech). In an environment where the surrounding stray light is shielded, the image is divided into 5 horizontal parts and 1 to 5 columns from left to right, and 1 to 5 lines from top to bottom when vertically divided into 5 parts. The imaging was performed so that a halogen light source (“ALA-100” manufactured by Asahi Corporation) was at the positions of 2 columns and 4 rows. At this time, among the ghosts that occurred in the regions from 1 column to 5 rows, the region with a red sensitivity of 80 or more was regarded as a ghost region, and its area was evaluated. 20% or less of the area from 1 column to 5 rows was set as ghosting performance ○, and those exceeding 20% were set as ghosting performance ×.

[Example 1]

The compound ( 14) (Maximum absorption wavelength: 887 nm, absolute value of the difference between (Aa) and (Ab): 94 nm, absorbance λ ₇₀₀ / absorbance λ _max : 0.08, absorbance λ ₇₅₁ / absorbance λ _max : 0.31) 0.078 parts by mass, and 0.05 part by mass of a phenolic antioxidant ("Adekastab AO-20", manufactured by ADEKA), and dichloromethane was further added and dissolved to obtain a solid content of 30% solution. Next, the obtained solution was cast-molded on a smooth glass plate, dried at 50° C. for 8 hours, further dried at 100° C. under reduced pressure for 1 hour, and then peeled off. By extending this resin film at 180°C, a base material having a thickness of 0.1 mm, one side of 60 mm, and an in-plane retardation R ₀ of 5 nm was obtained. "(950 - shortest absorption maximum wavelength) x dye concentration x dye medium thickness" of the obtained base material was 1.3, which satisfies the condition (c).

On both sides of the obtained base material, using an ion-assisted vacuum evaporation apparatus, the design (1) and design (2) [silicon dioxide (SiO ₂ : 550nm refractive index 1.46) layers and Titanium dioxide (TiO ₂ : Refractive index 2.48 at 550 nm) layers were alternately laminated] A near-infrared reflective film including a dielectric multilayer film was formed, and an optical filter having a thickness of 0.107 mm was obtained. The design (1) and design (2) are shown in Table 2. In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

Table 1 and FIG. 12 show the results of measuring the above-mentioned requirements (A) to (E) and (Za) for the transmittance and reflectance of the obtained optical filter.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was ○. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter is suitable for a solid-state imaging device having sensitivity to near infrared rays.

[Example 2]

Except changing the compound (14) in Example 1 to the compound (15) represented by the following formula (15) (maximum absorption wavelength: 898 nm, absolute value of the difference between (Aa) and (Ab): 110 nm, A substrate was obtained in the same procedure except that the absorbance λ ₇₀₀ /absorbance λ _max : 0.05 and the absorbance λ ₇₅₁ /absorbance λ _max : 0.1) 0.05 parts by mass. "(950 - shortest absorption maximum wavelength) x dye concentration x dye medium thickness" of the obtained base material was 0.74, which satisfies the condition (c).

[Chemical 15]

On both sides of the obtained substrate, an ion-assisted vacuum evaporation apparatus was used to design (2) [silicon dioxide (SiO ₂ : 550 nm refractive index 1.46) layer and titanium dioxide (TiO ₂ : 550 nm) layers at an evaporation temperature of 120° C. A refractive index of 2.48) layers were alternately laminated] A near-infrared reflective film containing a dielectric multilayer film was formed to obtain an optical filter with a thickness of 0.107 mm. The design (2) is shown in Table 2.

Table 1 shows the results of measuring the above-mentioned requirements (A) to (E) and (Za) for the transmittance and reflectance of the obtained optical filter. In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was ○. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter is suitable for a solid-state imaging device having sensitivity to near infrared rays.

[Example 3]

Except changing the compound (14) in Example 1 to the compound (16) represented by the following formula (16) (maximum absorption wavelength: 897 nm, absolute value of the difference between (Aa) and (Ab): 134 nm, A substrate was obtained in the same procedure except for absorbance λ ₇₀₀ /absorbance λ _max : 0.1 and absorbance λ ₇₅₁ / absorbance λ _max : 0.2) 0.064 parts by mass. "(950 - shortest absorption maximum wavelength) x dye concentration x dye medium thickness" of the obtained base material was 0.32, which satisfies the condition (c).

On both sides of the obtained substrate, an ion-assisted vacuum evaporation apparatus was used to design (3) [silicon dioxide (SiO ₂ : 550 nm refractive index 1.46) layer and titanium dioxide (TiO ₂ : 550 nm) layers at an evaporation temperature of 120° C. A refractive index of 2.48) layers were alternately laminated] A near-infrared reflective film containing a dielectric multilayer film was formed to obtain an optical filter with a thickness of 0.104 mm. The design (3) is shown in Table 2.

Table 1 shows the results of measuring the above-mentioned requirements (A) to (E) and (Za) for the transmittance and reflectance of the obtained optical filter. In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was ○. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter is suitable for a solid-state imaging device having sensitivity to near infrared rays.

[Example 4]

Except changing the compound (14) in Example 1 to the compound (17) represented by the following formula (17) (maximum absorption wavelength: 844 nm, absolute value of the difference between (Aa) and (Ab): 84 nm, A substrate was obtained in the same procedure except that the absorbance λ ₇₀₀ /absorbance λ _max : 0.08 and the absorbance λ ₇₅₁ /absorbance λ _max : 0.26) 0.05 parts by mass. "(950 - shortest absorption maximum wavelength) x dye concentration x dye medium thickness" of the obtained base material was 0.54, which satisfies the condition (c).

On both sides of the obtained substrate, an ion-assisted vacuum evaporation apparatus was used to design (3) [silicon dioxide (SiO ₂ : 550 nm refractive index 1.46) layer and titanium dioxide (TiO ₂ : 550 nm) layers at an evaporation temperature of 120° C. A refractive index of 2.48) layers were alternately laminated] A near-infrared reflective film containing a dielectric multilayer film was formed to obtain an optical filter with a thickness of 0.104 mm. The design (3) is shown in Table 2.

Table 1 shows the results of measuring the above-mentioned requirements (A) to (E) and (Za) for the transmittance and reflectance of the obtained optical filter. Furthermore, the wavelength of 700nm The lower reflectance was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was ○. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter is suitable for a solid-state imaging device having sensitivity to near infrared rays.

[Example 5]

A base material was obtained in the same procedure except that the amount of compound (14) in Example 1 was changed to 0.07 part by mass. "(950-shortest absorption maximum wavelength)×dye concentration×dye medium thickness" of the obtained base material was 1.1, and the condition (c) was satisfied.

On both sides of the obtained substrate, using an ion-assisted vacuum evaporation apparatus, at an evaporation temperature of 120° C., the design (4) and design (5) [silicon dioxide (SiO ₂ : 550nm refractive index 1.46) layers and Titanium dioxide (TiO ₂ : Refractive index 2.48 at 550 nm) layers are alternately laminated] A near-infrared reflective film including a dielectric multilayer film was formed, and an optical filter having a thickness of 0.104 mm was obtained. The design (4) and design (5) are shown in Table 2.

The results of measuring the above-mentioned requirements (A) to (E) and (Za) of the transmittance and reflectance of the obtained optical filter are shown in Table 1 and FIG. 13 . In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was ○. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter is suitable for a solid-state imaging device having sensitivity to near infrared rays.

[Example 6]

On a glass plate with a thickness of 0.1 mm (D263 manufactured by SCHOTT) After the following resin composition (1) was applied by spin coating, it was heated at 80° C. for 2 minutes on a hot plate, and the solvent was volatilized and removed, thereby forming a hardened layer. At this time, the coating conditions of the spin coater are adjusted so that the film thickness of the cured layer is about 0.8 μm.

Resin composition (1): 30 parts of isocyanuric ethylene oxide modified triacrylate (trade name: Aronix M-315, manufactured by Toa Gosei Chemical Co., Ltd.), 1,9- 20 parts of nonanediol diacrylate, 20 parts of methacrylic acid, 30 parts of glycidyl methacrylate, 5 parts of 3-glycidyloxypropyltrimethoxysilane, 1-hydroxycyclohexylbenzophenone (product Name: IRGACURE 184, 5 copies of Ciba specialty chemical (manufactured by Co., Ltd.) and 1 copy of Sunaide SI-110 main agent (manufactured by Sanxin Chemical Industry Co., Ltd.) A solution obtained by mixing and dissolving in propylene glycol monomethyl ether acetate so that the solid content concentration becomes 50% by mass, and then filtering through a microporous filter having a pore diameter of 0.2 μm.

The compound ( 14) 0.7 part by mass, and 0.1 part by mass of a phenolic antioxidant ("Adekastab AO-20" manufactured by ADEKA), and dichloromethane was further added and dissolved to obtain a solid The composition is a 10% solution (A) on a mass basis. On the hardened layer, the solution (A) was applied by a spin coater so that the film thickness after drying was 0.01 mm, and the solution (A) was heated on a hot plate at 80° C. for 30 minutes to volatilize and remove the solvent. A resin layer is formed. Next, it was exposed using a UV transmission exposure machine from the glass plate side (exposure amount: 500 mJ/cm ² , illuminance: 200 mW), and then calcined in an oven at 210° C. for 5 minutes to obtain a base comprising a glass substrate and a resin layer. material. "(950 - shortest absorption maximum wavelength) x dye concentration x dye medium thickness" of the obtained base material was 1.3, which satisfies the condition (c).

On both sides of the obtained substrate, using an ion-assisted vacuum evaporation apparatus, at an evaporation temperature of 120° C., the design (4) and design (5) [silicon dioxide (SiO ₂ : 550nm refractive index 1.46) layers and Titanium dioxide (TiO ₂ : Refractive index 2.48 at 550 nm) layers are alternately laminated] A near-infrared reflective film including a dielectric multilayer film was formed, and an optical filter having a thickness of 0.104 mm was obtained. The design (4) and design (5) are shown in Table 2.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was ○. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter is suitable for a solid-state imaging device having sensitivity to near infrared rays.

[Comparative Example 1]

To 100 parts by mass of norbornene resin "ARTON" (refractive index 1.52, glass transition temperature 160°C) manufactured by JSR Co., Ltd., an absorbent manufactured by QCR Solutions was added "NIR829A" (maximum absorption wavelength: 840 nm, absolute value of the difference between (Aa) and (Ab): 90 nm, absorbance λ ₇₀₀ / absorbance λ _max : 0.15, absorbance λ ₇₅₁ / absorbance λ _max : 0.38, the conditions are not satisfied (a)) 0.113 parts by mass, and 0.05 part by mass of a phenolic antioxidant ("Adekastab AO-20" manufactured by ADEKA), and further adding dichloromethane to dissolve, A solution having a solid content of 30% by mass was obtained. Next, the obtained solution was cast-molded on a smooth glass plate, dried at 50° C. for 8 hours, further dried at 100° C. under reduced pressure for 1 hour, and then peeled off. By extending this resin film at 150°C, a base material having a thickness of 0.1 mm, one side of 60 mm, and an in-plane retardation R ₀ of 5 nm was obtained. "(950 - shortest absorption maximum wavelength) x dye concentration x dye medium thickness" of the obtained base material was 1.2, which satisfies the condition (c).

On both sides of the obtained base material, using an ion-assisted vacuum evaporation apparatus, at an evaporation temperature of 120° C., the design (7) and design (6) [silicon dioxide (SiO ₂ : 550nm refractive index 1.46) layers and Titanium dioxide (TiO ₂ : Refractive index 2.48 at 550 nm) layers are alternately laminated] A near-infrared reflective film including a dielectric multilayer film was formed, and an optical filter having a thickness of 0.106 mm was obtained. The design (6) and design (7) are shown in Table 2.

Table 1 and FIG. 14 show the measurement results of the transmittance and reflectance of the obtained optical filter, and the results of the requirements (A) to (E) and (Za). In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was x. In addition, ghost evaluation was performed on the obtained optical filter, and as a result, the ghost performance was ○. The obtained optical filter has insufficient performance in a solid-state imaging device having sensitivity to near infrared rays.

[Comparative Example 2]

In a 500 mL five-neck flask equipped with a thermometer, a stirrer, a nitrogen introduction tube, a dropping funnel with a side tube, a Dean-Stark tube, and a cooling tube, 1,4- Bis(4-amino-α,α-dimethylbenzyl)benzene 27.66g (0.08mol ear) and 4,4'-bis(4-aminophenoxy)biphenyl 7.38g (0.02mol) dissolved in γ-butyrolactone 68.65g and N,N-dimethylacetamide 17.16g middle. The resulting solution was cooled to 5°C using an ice-water bath. While maintaining the same temperature, 22.62 g (0.1 moles) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and triethylamine as an imidization catalyst were added to the solution. 0.50 g (0.005 moles). After the addition was completed, the temperature was raised to 180°C, and the distillate was distilled off at any time, while refluxing for 6 hours. After completion of the reaction, after cooling in the air until the internal temperature reached 100°C, 143.6 g of N,N-dimethylacetamide was added for dilution, and it was cooled while stirring to obtain a polyamide having a solid content concentration of 20% by mass. Amine resin solution 264.16g. A part of this polyimide resin solution was poured into 1 L of methanol to precipitate the polyimide resin. The filtered polyimide resin was washed with methanol, and then dried in a vacuum dryer at 100° C. for 24 hours to obtain a white powdery polyimide resin. The glass transition temperature of the obtained polyimide resin was 310°C.

To 100 parts by mass of the obtained polyimide resin, in the formula (4), R ¹ is a hydrogen group, R ^1' is a methyl group, R ² is a hydrogen group, R ³ is an isopropyl group, and R ⁴ is a hydrogen group. Hydrogen group, R ⁵ is hydrogen group, R ⁶ is a methyl group of squaraine-based absorber (maximum absorption wavelength is 770nm, the absolute value of the difference between (Aa) and (Ab): 82nm, absorbance λ ₇₀₀ / Absorbance λ _max : 0.4, absorbance λ ₇₅₁ /absorbance λ _max : 0.9, 0.05 parts by mass not satisfying condition (a), and Rdi1 to Rdi8 in the formula (7-1) are tertiary butyl groups, Rdi9 to Rdi12 It is a diimmonium-based absorber in which a hydrogen group and an anion (X ⁻ ) is a bis(trifluoromethanesulfonyl)imide anion (maximum absorption wavelength: 1094 nm, the absolute difference between the (Aa) and (Ab) Value: 124 nm) 0.0005 parts by mass, N,N-dimethylacetamide was further added and dissolved to obtain a solution with a solid content of 30% by mass. Next, the obtained solution was cast-molded on a smooth glass plate, dried at 50° C. for 8 hours, and further dried at 140° C. under reduced pressure for 1 hour, and peeled off to obtain a base material having a thickness of 0.05 mm and a side of 60 mm. "(950-shortest absorption maximum wavelength)×dye concentration×dye medium thickness" of the obtained base material was 0.45, and the condition (c) was satisfied.

Both sides of the obtained base material were coated with a coating bar (AUTOMATIC FILM APPLICATOR, model No. 542-AB, manufactured by Yasuda Seiki Co., Ltd.), diluted with methyl ethyl ketone and containing a polymerization initiator. A solution of 2 parts by mass of an acrylate-based ultraviolet curable hard coat agent ("Desolite" Z-7524 manufactured by JSR Corporation) and a solid content concentration of 45% by mass. After drying at 80°C for 3 minutes, using a UV transmission type ultraviolet curing device "US2-X040560Hz" manufactured by Eye Graphics, the illuminance of a metal halide lamp in a nitrogen atmosphere was 270mW/cm ² , and the cumulative UV curing was performed with a light amount of 150 mJ/cm ² to obtain a 0.052 mm-thick laminate having a hard coat layer with a thickness of 1 μm on both surfaces of the resin film.

Using an ion-assisted vacuum evaporation apparatus, the design (8) and design (6) [silicon dioxide (SiO ₂ : 550nm refractive index 1.46) layers and the Titanium dioxide (TiO ₂ : Refractive index 2.48 at 550 nm) layers were alternately laminated] to form a near-infrared reflective film including a dielectric multilayer film to obtain an optical filter with a thickness of 0.056 mm. The design (8) and design (6) are shown in Table 2.

Table 1 shows the measurement results of the transmittance and reflectance of the obtained optical filter, and the results of the above-mentioned requirements (A) to (E) and (Za). In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was x. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter has insufficient performance in a solid-state imaging device having sensitivity to near infrared rays.

[Comparative Example 3]

In a 3L four-necked flask, 35.12 g (0.253 mol) of 2,6-difluorobenzonitrile, 87.60 g (0.250 mol) of 9,9-bis(4-hydroxyphenyl) fluorene, and 41.46 g (0.300 mol) of potassium carbonate were added. mol), N,N-dimethylacetamide (hereinafter also referred to as "DMAc") 443 g and toluene 111 g. Next, a thermometer, a stirrer, a three-way stopcock with a nitrogen introduction tube, a Dean-Stark tube, and a cooling tube were attached to the four-necked flask. Next, after nitrogen-purging the inside of the flask, the obtained solution was allowed to react at 140° C. for 3 hours, and the generated water was removed from the Dean-Stark tube at any time. The generation of water was not confirmed, and the temperature was gradually raised to 160°C, and the reaction was carried out at this temperature for 6 hours. After cooling to room temperature (25°C), the generated salt was removed with filter paper, the filtrate was poured into methanol for reprecipitation, and the filtrate (residue) was separated by filtration. The obtained filtrate was vacuum-dried at 60°C overnight to obtain a polyether resin. The obtained polyether resin had a refractive index of 1.60 and a glass transition temperature of 285°C.

To 100 parts by mass of the obtained polyether resin was added an absorber "SDB4927" (maximum absorption wavelength: 825 nm, absolute value of the difference between (Aa) and (Ab): 98 nm, absorbance λ ₇₀₀ /absorbance λ _max : 0.1, absorbance λ ₇₅₁ /absorbance λ _max : 0.3) 0.05 parts by mass, and dichloromethane was further added and dissolved to obtain a solution with a solid content of 15% by mass. Next, the obtained solution was spin-coated on a smooth glass plate with a thickness of 0.1 mm (D263 manufactured by SCHOTT), dried at 50° C. for 8 hours, and further dried at 150° C. under reduced pressure for 1 hour to form A resin layer with a thickness of 0.01 mm was obtained, whereby a base material having a side of 60 mm including a glass plate and a resin layer was obtained. The in-plane retardation R ₀ of the obtained base material was 8 nm.

Next, the design (7) and design (6) [silicon dioxide (SiO ₂ : refractive index 1.46 at 550 nm) layers were formed on both sides of the obtained base material at an evaporation temperature of 120° C. using an ion-assisted vacuum evaporation device. A near-infrared reflective film including a dielectric multilayer film was formed by alternately laminating layers of titanium dioxide (TiO ₂ : 550 nm refractive index 2.48) to obtain an optical filter with a thickness of 0.116 mm. The design (7) and design (6) are shown in Table 2.

Table 1 shows the measurement results of the transmittance and reflectance of the obtained optical filter, and the results of the above-mentioned requirements (A) to (E) and (Za). In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was x. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter has insufficient performance in a solid-state imaging device having sensitivity to near infrared rays.

[Comparative Example 4]

To 100 parts by mass of norbornene resin "ARTON" (refractive index 1.52, glass transition temperature 160°C) manufactured by JSR Co., Ltd., an absorbent manufactured by Few Chemicals was added "S-2084" (maximum absorption wavelength: 667 nm, absolute value of the difference between (Aa) and (Ab): 26 nm, absorbance λ ₇₀₀ / absorbance λ _max : 0.06, absorbance λ ₇₅₁ / absorbance λ _max : 0.0, no 0.0087 parts by mass of the condition (b) was satisfied, and dichloromethane was further added and dissolved to obtain a solution having a solid content of 30% by mass. Next, the obtained solution was cast-molded on a smooth glass plate, dried at 50° C. for 8 hours, and further dried at 140° C. under reduced pressure for 3 hours, and then peeled off to obtain a substrate having a thickness of 0.1 mm and a side of 60 mm. "(950 - shortest absorption maximum wavelength) x dye concentration x dye medium thickness" of the obtained base material was 1.26, which satisfies the condition (c).

Next, on both sides of the obtained base material, using an ion-assisted vacuum evaporation apparatus, at an evaporation temperature of 120° C., design (1) and design (9) [silicon dioxide (SiO ₂ : Refractive index of 550 nm: 1.46) Layers and titanium dioxide (TiO ₂ : 550 nm refractive index 2.48) layers were alternately laminated] to form a near-infrared reflective film including a dielectric multilayer film to obtain an optical filter with a thickness of 0.106 mm. The design (1) and design (9) are shown in Table 2.

Table 1 and FIG. 15 show the measurement results of the transmittance and reflectance of the obtained optical filter, and the results of the requirements (A) to (E) and (Za). Furthermore, the reflectance at a wavelength of 700 nm exceeded 10%.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was x. In addition, ghost evaluation was performed, and as a result, the ghost performance was x. earned The performance of an optical filter is insufficient in a solid-state imaging device having sensitivity to near-infrared rays.

[Comparative Example 5]

To 100 parts by mass of norbornene resin "ARTON" (refractive index 1.52, glass transition temperature 160°C) manufactured by JSR Co., Ltd., an absorbent "SMP" manufactured by Hayashihara Co., Ltd. was added. -54" (maximum absorption wavelength: 721 nm, absolute value of the difference between (Aa) and (Ab): 65 nm, absorbance λ ₇₀₀ / absorbance λ _max : 0.53, absorbance λ ₇₅₁ / absorbance λ _max : 0.08, the conditions are not satisfied (a) and (b)) 0.05 mass part, dichloromethane was further added, it melt|dissolved, and the solution whose solid content was 30% by mass was obtained. Next, the obtained solution was cast-molded on a smooth glass plate, dried at 50° C. for 3 hours, further dried at 100° C. under reduced pressure for 3 hours, and then peeled off to obtain a base material having a thickness of 0.1 mm and a side of 60 mm. "(950-shortest absorption maximum wavelength)×dye concentration×dye medium thickness" of the obtained base material was 1.15, and the condition (c) was satisfied.

On both sides of the obtained base material, using an ion-assisted vacuum evaporation apparatus, at an evaporation temperature of 120° C., design (2) and design (10) [silicon dioxide (SiO ₂ : 550 nm refractive index 1.45, film thickness 1.45) 37nm~194nm) layer and titanium dioxide (TiO ₂ : 550nm refractive index 2.45, film thickness 11nm~108nm) layers alternately laminated] to form a near-infrared reflective film containing a dielectric multilayer film to obtain an optical filter with a thickness of 0.106mm device.

Table 1 shows the measurement results of the transmittance and reflectance of the obtained optical filter, and the results of the above-mentioned requirements (A) to (E) and (Za). Furthermore, the wavelength The reflectance at 700nm exceeds 10%.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was x. In addition, ghost evaluation was performed, and as a result, the ghost performance was x. The obtained optical filter has insufficient performance in a solid-state imaging device having sensitivity to near infrared rays.

[Comparative Example 6]

To 100 parts by mass of the norbornene resin "ARTON" (refractive index 1.52, glass transition temperature 160°C) manufactured by JSR Co., Ltd., 0.05 mass part of the compound (15) and the following were added. Compound (18) represented by the formula (18) (maximum absorption wavelength: 1064 nm, absolute value of the difference between (Aa) and (Ab): 139 nm, absorbance λ ₇₀₀ / absorbance λ _max : 0.05, absorbance λ ₇₅₁ / Absorbance λ _max : 0.1) 0.04 parts by mass, and dichloromethane was further added and dissolved to obtain a solution having a solid content of 30% by mass. Next, the obtained solution was cast-molded on a smooth glass plate, dried at 50° C. for 3 hours, further dried at 100° C. under reduced pressure for 3 hours, and then peeled off to obtain an optical filter with a thickness of 0.1 mm and a side of 60 mm. .

[Chemical 18]

Table 1 shows the measurement results of the transmittance and reflectance of the obtained optical filter, and the results of the above-mentioned requirements (A) to (E) and (Za). In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was x, and the near-infrared sensitivity was ○. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter has insufficient performance in a solid-state imaging device having sensitivity to near infrared rays.

[Comparative Example 7]

On both sides of a glass substrate (D263 manufactured by SCHOTT, thickness 0.1 mm), an ion-assisted vacuum evaporation device was used, and the design (1) and design shown in Table 2 were used at an evaporation temperature of 120°C, respectively. (12) [Silicon dioxide (SiO ₂ : Refractive index 1.46 at 550 nm) layers and titanium dioxide (TiO ₂ : Refractive index 2.48 at 550 nm) layers are alternately laminated] A dielectric multilayer film is formed, thereby obtaining an optical filter . Table 1 and FIG. 16 show the measurement results of the transmittance and reflectance of the obtained optical filter, and the results of the above-mentioned requirements (A) to (E) and (Za). In addition, the reflectance at a wavelength of 700 nm was 10% or less on any surface.

As a result of sensitivity evaluation of this optical filter, the green sensitivity was ○, and the near-infrared sensitivity was x. In addition, ghost evaluation was performed, and as a result, the ghost performance was ○. The obtained optical filter has insufficient performance in a solid-state imaging device having sensitivity to near infrared rays.

[Industrial availability]

The optical filter of the present invention is useful as a sensitivity correction for a solid-state imaging element having a near-infrared sensitivity with a wavelength of 700 nm to 750 nm, such as a CCD or a CMOS of a camera module. Especially for digital still cameras, cameras for mobile phones, cameras for smart phones, digital video cameras, PC cameras, surveillance cameras, automotive cameras, televisions, navigators, portable information terminals, personal computers, video game consoles, It is useful in portable game consoles, fingerprint authentication systems, iris authentication systems, face authentication systems, distance measuring sensors, distance measuring cameras, digital music players, vegetation sensing systems, cerebral blood flow sensing systems, and the like.

Claims (12)

An optical filter, characterized in that the optical filter has a base material and a near-infrared reflective film, the base material includes a resin layer containing a near-infrared absorbing agent, and the near-infrared reflective film is formed on the base material. On at least one side, the near-infrared absorbing agent has an absorption maximum wavelength in a wavelength range of 751 nm to 950 nm, and the near-infrared absorbing agent is contained in an amount of 10% of the transmittance of the substrate at the absorption maximum wavelength. In the case of a near-infrared absorber, the longest wavelength (Aa) at which the transmittance of the base material is 70% in a range of a wavelength of 430 nm or more and the absorption maximum wavelength or less, and the base material in a range of a wavelength of 580 nm or more. The absolute value of the difference between the shortest wavelengths (Ab) at which the transmittance of the material is 30% is less than 150nm, and the following necessary conditions (A)~(D) are satisfied: (A) Within the wavelength range of 430nm~580nm, from relative to The average value of transmittance measured in the direction perpendicular to the surface of the optical filter is 75% or more; (B) The transmittance measured in the direction perpendicular to the surface of the optical filter in the wavelength range of 800nm to 1000nm The average value is 10% or less; (C) in the wavelength range of 700nm to 750nm, the average value of transmittance measured from the direction perpendicular to the surface of the optical filter exceeds 46%; (D) in the wavelength range of 560nm to 800nm The value (Ya) of the shortest wavelength with a transmittance of 50% when measured from a direction perpendicular to the surface of the optical filter and measured at an angle of 30° from a direction perpendicular to the surface of the optical filter The absolute value of the difference between the shortest wavelength values (Yb) with a transmittance of 50% is less than 15 nm. The optical filter according to claim 1, wherein the optical filter further satisfies the following requirement (E): (E) The value (Ya) of the wavelength is 730 nm or more and 800 nm or less. The optical filter according to claim 1, wherein the resin layer contains a resin selected from the group consisting of polyester-based resin, polyether-based resin, acrylic-based resin, polyolefin-based resin, polycycloolefin-based resin, and norbornene resin, polycarbonate resin, enethiol resin, epoxy resin, polyamide resin, polyimide resin, polyurethane resin, polystyrene resin at least one of the groups. The optical filter according to claim 3, wherein the near-infrared reflective film is formed by laminating a high-refractive-index material layer and a low-refractive-index material layer. The optical filter according to claim 4, wherein the high refractive index material layer has a refractive index of 1.7 to 2.5, and the low refractive index material layer has a refractive index of 1.2 or more and less than 1.7. The optical filter according to claim 4, wherein the total number of laminated layers of the high refractive index material layer and the low refractive index material layer is 5 to 60 layers. The optical filter according to claim 1, wherein the resin layer comprises at least one selected from the group consisting of norbornene-based resin, polyimide-based resin, and polyether resin. The optical filter according to claim 1, wherein the near-infrared is contained in a range of 0.01 mass % to 60.0 mass % with respect to the resin layer Line Absorber. The optical filter according to claim 1, wherein the near-infrared reflective film is a dielectric multilayer film. The optical filter according to claim 1, wherein the optical filter satisfies the following necessary conditions (Z1) and (Z2): (Z1) at a wavelength of 700 nm, from a plane perpendicular to the optical filter The reflectance when measured at an angle of 5° in the direction of the optical filter is 10% or less regardless of which surface of the optical filter is incident; (Z2) In the range of wavelength 600nm or more, from the surface perpendicular to the optical filter The value (Za) of a wavelength of 600 nm or more with a reflectance of 50% when the direction is measured at an angle of 5° is 730 nm or more when incident from any surface of the optical filter. A solid-state imaging device characterized by comprising the optical filter described in any one of claims 1 to 10 of the scope of the patent application. A camera module is characterized by comprising the optical filter described in any one of items 1 to 10 of the scope of the patent application.

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