TWI889361B - Optical filter and matching composite layer thereof - Google Patents

Abstract

The present invention provides an optical filter and a matching composite layer thereof. The matching composite layer includes a plurality of first refraction layers, a plurality of second refraction layers, and a plurality of third refraction layers. A refractive layer of the second refraction layer is greater than that of the first refraction layer, and is less than that of the third refraction layer. Any two of the second refraction layers provided with one of the first refraction layers sandwiched there-between are sandwiched between two of the third refraction layers so as to be jointly defined as a bidirectional incremental module. A quantity of the bidirectional incremental module included in the matching composite layer is at least M that is a positive integer greater than three. The M number of the bidirectional incremental modules are stacked and connected with each other.

Description

Optical filters and matching composite layers

The present invention relates to a filter, and in particular to an optical filter and a matching composite layer thereof.

Existing optical filters often use multiple refractive layers stacked in sequence, and the difference between the two refractive indices they have is relatively large. However, the configuration structure of existing optical filters has gradually failed to meet the different needs of today. Therefore, the inventors of the present invention believe that the above defects can be improved, and have conducted intensive research and applied scientific principles, and finally proposed a reasonable design and effective improvement of the above defects.

The present invention provides an optical filter and a matching composite layer thereof, which can effectively improve the defects that may be produced by the existing optical filter.

The present invention discloses an optical filter, which includes: a substrate; a bonding layer formed on the substrate, and the refractive index of the bonding layer is less than 1.42; and a matching composite layer formed on the bonding layer, and the matching composite layer has N film layers stacked in sequence, N is a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index greater than that of the bonding layer; The matching composite layer comprises a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; wherein the matching composite layer is formed by connecting the third refractive layer to the bonding layer and is defined as a first film layer; and the matching composite layer is formed by connecting the first refractive layer to the first film layer and is defined as a second film layer; the matching composite layer is configured with the first refractive layer at the end far from the bonding layer and is defined as an Nth film layer; wherein, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one of the first refractive layers is sandwiched between the inner sides of any two adjacent second refractive layers, and is sandwiched between the two third refractive layers on the outer sides, and further The optical filter is commonly defined as a bidirectional reciprocal module; wherein the number of the bidirectional reciprocal modules included in the matching composite layer is at least M and they are stacked in a connected manner; wherein M is a positive integer and M is greater than 3; wherein the optical filter can be used to form a reflectivity of no more than 10% for an incident light that is 60 degrees away from its normal direction and has a wavelength between 400 nanometers (nm) and 650 nanometers.

The present invention also discloses an optical filter, which includes: a substrate; a bonding layer formed on the substrate; and a matching composite layer formed on the bonding layer, and the matching composite layer has N film layers stacked in sequence, N is a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index greater than the refractive index of the bonding layer; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; wherein the matching composite layer is connected to the bonding layer with one third refractive layer and is defined as a first film layer; ... The combining layer is formed by connecting the first film layer with the first refractive layer and is defined as a second film layer; the matching composite layer is formed by configuring the film layer far from the end of the combining layer and is defined as an Nth film layer; wherein, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one of the first refractive layers is sandwiched between the inner sides of any two adjacent second refractive layers, and is sandwiched between the two third refractive layers on the outer sides, thereby jointly defining a bidirectional reciprocating module; wherein the number of the bidirectional reciprocating modules included in the matching composite layer is at least M and they are stacked and connected to each other; wherein M is a positive integer and M is greater than 3.

The present invention also discloses a matching composite layer of an optical filter, which includes: N film layers stacked in sequence, and N is a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; wherein the third refractive layer located at one end of the matching composite layer is defined as a first film layer; the matching composite layer is formed by connecting the first refractive layer to the first film layer and defining the first refractive layer as a first film layer. The second film layer is defined as a second film layer; the film layer located at the other end of the matching composite layer is defined as an Nth film layer; wherein, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one of the first refractive layers is sandwiched between the inner sides of any two adjacent second refractive layers, and is sandwiched between two third refractive layers on the outer sides, thereby jointly defining a bidirectional reciprocal module; wherein the number of the bidirectional reciprocal modules included in the matching composite layer is at least M and they are stacked and connected with each other; wherein M is a positive integer, and M is greater than 3.

In summary, the optical filter and the matching composite layer disclosed in the embodiments of the present invention form M bidirectional amplification modules that are different from the known bidirectional amplification modules that are stacked one after another, and the refractive index of each bidirectional amplification module can be gradually increased from the first refractive layer toward two opposite directions, so as to adjust the overall refractive index distribution of the matching composite layer, thereby helping the optical filter to be designed to meet more diverse different needs.

In order to further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, such description and drawings are only used to illustrate the present invention and do not limit the protection scope of the present invention in any way.

The following is an explanation of the implementation of the "optical filter and its matching composite layer" disclosed in the present invention through specific concrete embodiments. Technical personnel in this field can understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed in various ways based on different viewpoints and applications without deviating from the concept of the present invention. In addition, the drawings of the present invention are only simple schematic illustrations and are not depicted according to actual sizes. Please note in advance. The following implementation will further explain the relevant technical contents of the present invention in detail, but the disclosed contents are not intended to limit the scope of protection of the present invention.

It should be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various components or signals, these components or signals should not be limited by these terms. These terms are mainly used to distinguish one component from another component, or one signal from another signal. In addition, the term "or" used herein may include any one or more combinations of the associated listed items depending on the actual situation.

Please refer to FIG. 1 to FIG. 3 , which are an embodiment of the present invention. This embodiment discloses an optical filter 1000, which is preferably a flat sheet structure. The optical filter 1000 in this embodiment can be applied to visible light (eg, 420 nm to 720 nm).

In this embodiment, the optical filter 1000 includes a substrate 200, a bonding layer 300 formed on the substrate 200, and a matching composite layer 100 formed on the bonding layer 300. The substrate 200 is, for example, a glass substrate, such as a blue glass (blue glass or IR cut glass), and the matching composite layer 100 is bonded to the substrate 200 through the bonding layer 300, but the present invention is not limited thereto. For example, in other embodiments not shown in the present invention, the matching composite layer 100 can be used in conjunction with other components.

Specifically, the matching composite layer 100 has N film layers 10 stacked in sequence. The N film layers 10 are preferably stacked along the thickness direction H, and the side edges of the N film layers 10 are aligned with each other and are preferably further aligned with the side edges of the bonding layer 300. Furthermore, N is a positive integer (e.g., N can be limited to between 30 and 80), and N is illustrated as 44 in this embodiment (that is, the plurality of film layers 10 and the bonding layer 300 are illustrated as 45 layers in total in this embodiment), but the present invention is not limited thereto.

Specifically, the N film layers 10 can be divided into a plurality of first refractive layers 10-1, a plurality of second refractive layers 10-2, and a plurality of third refractive layers 10-3 according to the refractive index. Each of the first refractive layers 10-1 has a first refractive index greater than the refractive index of the bonding layer 300. Each of the second refractive layers 10-2 has a second refractive index greater than the first refractive index, and each of the third refractive layers 10-3 has a third refractive index greater than the second refractive index.

In addition, to facilitate understanding of the overall configuration of the matching composite layer 100, the plurality of film layers 10 can also be described by their stacking order; that is, the matching composite layer 100 is connected to the bonding layer 300 with a third refractive layer 10-3 and is defined as a first film layer 1; the matching composite layer 100 is connected to the first film layer 1 with a first refractive layer 10-1 and is defined as a second film layer 2; the matching composite layer 100 is configured with a film layer 10 far from the end of the bonding layer 300 and is defined as an Nth film layer N. The Nth film layer N is described as the first refractive layer 10-1 in this embodiment, but in other embodiments not shown in the present invention, the Nth film layer N may also be made of other materials (such as the second refractive layer 10-2 or the third refractive layer 10-3) according to actual needs.

In this embodiment, the refractive index of the bonding layer 300 is less than 1.42 (e.g., between 1.35 and 1.42), the first refractive index may be between 1.35 and 1.58, the second refractive index may be between 1.62 and 1.93, and the third refractive index may be between 2.0 and 2.8. In other words, the optical filter 1000 in this embodiment uses four optical layers with different refractive indices for stacking, thereby providing a more diverse optical configuration and structure.

It should be noted that, for the convenience of understanding the present embodiment, the bonding layer 300, the first refractive layer 10-1, the second refractive layer 10-2, and the third refractive layer 10-3 are described below using a feasible material as an example, but the present invention is not limited thereto. The bonding layer 300 is, for example, a magnesium fluoride (MgF ₂ ) layer, the first refractive layer 10-1 is, for example, a silicon dioxide (SiO ₂ ) layer, the second refractive layer 10-2 is, for example, an aluminum oxide (Al ₂ O ₃ ) layer, and the third refractive layer 10-3 is, for example, a titanium dioxide (TiO ₂ ) layer, but the present invention is not limited thereto. For example, in other embodiments not shown in the present invention, the bonding layer 300 is not limited to a material with a refractive index less than 1.42, and the bonding layer 300 may be made of other materials (such as: one of the first refractive layer 10-1, the second refractive layer 10-2, and the third refractive layer 10-3) according to actual needs; that is, the first refractive index may also be less than or equal to the refractive index of the bonding layer 300.

Furthermore, in the portion of the matching composite layer 100 sandwiched between the second film layer 2 and the Nth film layer N, one first refractive layer 10-1 is sandwiched between the inner sides of any two adjacent second refractive layers 10-2, and two third refractive layers 10-3 are sandwiched between them on the outer sides, thereby jointly defining a bidirectional amplification module 10a.

Furthermore, the number of the bidirectional reciprocal modules 10a included in the matching composite layer 100 is at least M and they are stacked in a connected configuration, and the M bidirectional reciprocal modules 10a stacked in a connected configuration in this embodiment are the third film layer 3 to the N-1th film layer N-1 of the matching composite layer 100. Wherein, M is a positive integer greater than 3, and M is illustrated as 10 in this embodiment, but the present invention is not limited thereto. That is, M is illustrated as being greater than N/5 in this embodiment, but in other embodiments not shown in the present invention, M may also be greater than N/4.

Accordingly, in any of the bidirectional increasing modules 10a, any of the second refractive layers 10-2 is sandwiched between one of the first refractive layers 10-1 and one of the third refractive layers 10-3, so that the refractive index thereof can present a slowly increasing distribution.

As described above, the optical filter 1000 in this embodiment is formed by M bidirectional amplification modules 10a which are different from the known bidirectional amplification modules 10a which are connected and stacked with each other, and the refractive index of each bidirectional amplification module 10a can be gradually increased from the first refractive layer 10-1 toward two opposite directions, so as to adjust the overall refractive index distribution of the matching composite layer 100, thereby helping the optical filter 1000 to be designed to meet more diverse different requirements.

It should be further explained that in order for the optical filter 1000 disclosed in this embodiment to have a lower reflectivity when facing a vertically incident light source (e.g., light with a wavelength between 400 nm and 720 nm) and being rotated to an angle of incidence between 30 and 60 degrees, the matching composite layer 100 preferably meets at least part of the following configuration conditions, but the present invention is not limited thereto.

In this embodiment, each of the bi-directional incremental modules 10a has a module thickness T10a, which is preferably between 320 nm and 380 nm. Furthermore, in the present embodiment, the plurality of bidirectional incremental modules 10a adopt different module thicknesses T10a (e.g., 376.49 mm, 364.05 mm, 372.95 mm, 354.67 mm, 332.94 mm, 324.5 mm, 325.44 mm, 326.12 mm, 325.09 mm, and 336.59 mm), but the module thicknesses T10a of any two bidirectional incremental modules 10a can be adjusted to be different or the same according to actual needs, and the present invention is not limited thereto.

Furthermore, in order to precisely control the optical filter 1000 to achieve a better optical effect within a preset thickness, any two adjacent bidirectionally recursive modules 10a in this embodiment share a third refractive layer 10-3 having a common thickness T10a-1. Further, the sum of the module thicknesses T10a of the plurality of bidirectionally recursive modules 10a is greater than a total thickness T100 of the matching composite layer 100. The sum of the common thicknesses T10a-1 of the plurality of bidirectionally recursive modules 10a is 20% to 25% of the sum of the module thicknesses T10a, thereby effectively controlling the total thickness T100 of the matching composite layer 100. In this embodiment, the sum of the module thicknesses T10a of the plurality of bidirectional incremental modules 10a may be controlled to be 105% to 140% of the total thickness T100 of the matching composite layer 100, but the present invention is not limited thereto.

From another perspective, in order for each of the bidirectionally increasing modules 10a to achieve a better optical effect of its bidirectionally increasing refractive index, each of the bidirectionally increasing modules 10a preferably meets at least part of the following configuration conditions, but the present invention is not limited thereto.

Specifically, in each of the bi-directional reciprocating modules 10a, the thickness of the two second refractive layers 10-2 is smaller than the thickness of the first refractive layer 10-1 and smaller than the thickness of any of the third refractive layers 10-3; wherein the thickness of the two second refractive layers 10-2 has a difference of less than 10 nanometers, and the thickness of the two third refractive layers 10-3 has a difference of less than 15 nanometers. In addition, in a plurality of the bi-directional refractive modules 10a, the difference between the minimum thickness and the maximum thickness of the first refractive layer 10-1 is not greater than 15 nanometers.

In more detail, the bonding layer 300 and the matching composite layer 100 of the optical filter 1000 in this embodiment adopt the specific configuration shown in FIG. 2 , and after performing corresponding simulation experiments, the results shown in FIG. 3 are obtained.

Accordingly, as shown by curve A30 in FIG3 , the optical filter 1000 can be used to form a reflectivity of no more than 1% (e.g., about 0.69%) for incident light with a wavelength between 400 nm and 720 nm and an angle of 30 degrees to the normal direction thereof. As shown by curve A40 in FIG3 , the optical filter 1000 can be used to form a reflectivity of no more than 1.5% (e.g., about 1.1%) for incident light with a wavelength between 400 nm and 720 nm and an angle of 40 degrees to the normal direction thereof. Furthermore, as shown by curve A60 in FIG3 , the optical filter 1000 can be used to form a reflectivity of no more than 10% (e.g., about 7.2%) for incident light with a wavelength between 400 nm and 650 nm and an angle of 60 degrees with respect to its normal direction. In addition, curve A0 in FIG3 shows the reflectivity of the optical filter 1000 and incident light along its normal direction.

[Technical Effects of the Embodiments of the Invention]

In summary, the optical filter and the matching composite layer disclosed in the embodiments of the present invention form M bidirectional amplification modules that are different from the known bidirectional amplification modules that are stacked one after another, and the refractive index of each bidirectional amplification module can be gradually increased from the first refractive layer toward two opposite directions, so as to adjust the overall refractive index distribution of the matching composite layer, thereby helping the optical filter to be designed to meet more diverse different needs.

The above disclosed contents are only preferred feasible embodiments of the present invention and are not intended to limit the patent scope of the present invention. Therefore, all equivalent technical changes made using the contents of the specification and drawings of the present invention are included in the patent scope of the present invention.

1000: Optical filter 100: Matching composite layer 10: Film layer 10-1: First refractive layer 10-2: Second refractive layer 10-3: Third refractive layer 1: First film layer 2: Second film layer 3: Third film layer N: Nth film layer N-1: N-1th film layer 10a: Bidirectional incremental module 200: Substrate 300: Bonding layer T10a: Module thickness T10a-1: Common thickness T100: Total thickness H: Thickness direction A0, A30, A40, A50, A60: Curves

FIG1 is a schematic plan view of an optical filter according to an embodiment of the present invention.

FIG2 is a specific configuration diagram of FIG1.

FIG. 3 is a schematic diagram of a simulation test of the optical filter in FIG. 2 at different angles.

1000:Optical filter

100: Matching composite layer

10: Membrane layer

10-1: First refractive layer

10-2: Second refractive layer

10-3: The third refractive layer

1: First film layer

2: Second film layer

3: The third film layer

N: Nth film layer

N-1: N-1th film layer

10a: Bidirectional incremental module

200:Substrate

300: Binding layer

T10a: Module thickness

T10a-1: Common thickness

T100:Total thickness

H: thickness direction

Claims (20)

An optical filter, comprising: a substrate; a bonding layer formed on the substrate, and the refractive index of the bonding layer is less than 1.42; and a matching composite layer formed on the bonding layer, and the matching composite layer has N film layers stacked in sequence, N being a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index greater than the refractive index of the bonding layer; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; Wherein, the matching composite layer is connected to the bonding layer with a third refractive layer and is defined as a first film layer; the matching composite layer is connected to the first film layer with a first refractive layer and is defined as a second film layer; the matching composite layer is configured with a first refractive layer at the end far from the bonding layer and is defined as an Nth film layer; Wherein, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one first refractive layer is sandwiched between the inner sides of any two adjacent second refractive layers, and is sandwiched between the two third refractive layers on the outer side, thereby jointly defining a bidirectional reciprocating module; Wherein, the number of the bidirectional reciprocal modules included in the matching composite layer is at least M and they are stacked and connected to each other; wherein M is a positive integer and M is greater than 3; Wherein, the optical filter can be used to make an incident light with a wavelength between 400 nanometers (nm) and 650 nanometers and an angle of 60 degrees with its normal direction form a reflectivity of no more than 10%. An optical filter as described in claim 1, wherein any two adjacent bidirectional amplification modules share a third refractive layer; wherein N is further limited to be between 30 and 80. An optical filter as described in claim 1, wherein any two adjacent bidirectionally increasing modules share a third refractive layer, and each of the bidirectionally increasing modules has a module thickness, and the sum of the module thicknesses of multiple bidirectionally increasing modules is greater than a total thickness of the matching composite layer. An optical filter as described in claim 1, wherein any two adjacent bidirectional gain modules share a third refractive layer, and each of the bidirectional gain modules has a module thickness, and the sum of the module thicknesses of multiple bidirectional gain modules is 105% to 140% of the total thickness of the matching composite layer. An optical filter as described in claim 1, wherein any two adjacent bidirectionally recursive modules share a third refractive layer having a common thickness; and each of the bidirectionally recursive modules has a module thickness; wherein the sum of the multiple common thicknesses of the multiple bidirectionally recursive modules is 20% to 25% of the sum of the multiple module thicknesses. An optical filter as described in any one of claims 3 to 5, wherein the module thickness of each of the bidirectional reciprocal modules is between 320 nanometers and 380 nanometers. An optical filter as described in claim 1, wherein, in each of the bidirectional amplification modules, the thickness of the two second refractive layers is respectively smaller than the thickness of the first refractive layer and also smaller than the thickness of any one of the third refractive layers. An optical filter as described in claim 1, wherein, in a plurality of the bidirectional amplification modules, a difference between a minimum thickness and a maximum thickness of the first refractive layer is no greater than 15 nanometers. An optical filter as described in claim 1, wherein, in each of the bidirectional amplification modules, the thicknesses of the two second refractive layers have a difference of less than 10 nanometers. An optical filter as described in claim 1, wherein, in each of the bidirectional amplification modules, the thicknesses of the two third refractive layers have a difference of less than 15 nanometers. An optical filter as described in claim 1, wherein the refractive index of the bonding layer is between 1.35 and 1.42, the first refractive index is between 1.35 and 1.58, the second refractive index is between 1.62 and 1.93, and the third refractive index is between 2.0 and 2.8. An optical filter, comprising: a substrate; a bonding layer formed on the substrate; and a matching composite layer formed on the bonding layer, wherein the matching composite layer has N film layers stacked in sequence, N being a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index greater than the refractive index of the bonding layer; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; Wherein, the matching composite layer is connected to the bonding layer with a third refractive layer and is defined as a first film layer; the matching composite layer is connected to the first film layer with a first refractive layer and is defined as a second film layer; the matching composite layer is configured with a film layer at the end far from the bonding layer and is defined as an Nth film layer; Wherein, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one first refractive layer is sandwiched between the inner sides of any two adjacent second refractive layers, and is sandwiched between the two third refractive layers on the outer side, thereby jointly defining a bidirectional reciprocating module; The number of the bidirectional incremental modules included in the matching composite layer is at least M and they are connected and stacked with each other; M is a positive integer and is greater than 3. An optical filter as described in claim 12, wherein any two adjacent bidirectional amplification modules share a third refractive layer; wherein N is further limited to be between 30 and 80. An optical filter as described in claim 12, wherein any two adjacent bidirectionally increasing modules share a third refractive layer, and each of the bidirectionally increasing modules has a module thickness, and the sum of the module thicknesses of multiple bidirectionally increasing modules is greater than a total thickness of the matching composite layer. An optical filter as described in claim 12, wherein, in each of the bidirectional amplification modules, the thickness of the two second refractive layers is respectively less than the thickness of the first refractive layer and less than the thickness of any of the third refractive layers; wherein, in each of the bidirectional amplification modules, the thickness of the two second refractive layers has a difference of less than 10 nanometers, and the thickness of the two third refractive layers has a difference of less than 15 nanometers. An optical filter as described in claim 15, wherein, in a plurality of the bidirectional amplification modules, a difference between a minimum thickness and a maximum thickness of the first refractive layer is no greater than 15 nanometers. A matching composite layer of an optical filter, comprising: N film layers stacked in sequence, and N is a positive integer; wherein the N film layers include: a plurality of first refractive layers, each having a first refractive index; a plurality of second refractive layers, each having a second refractive index greater than the first refractive index; and a plurality of third refractive layers, each having a third refractive index greater than the second refractive index; wherein a third refractive layer located at one end of the matching composite layer is defined as a first film layer; the matching composite layer is connected to the first film layer with a first refractive layer and is defined as a second film layer; a film layer located at the other end of the matching composite layer is defined as an Nth film layer; Among them, in the portion of the matching composite layer sandwiched between the second film layer and the Nth film layer, one of the first refractive layers is sandwiched between the inner sides of any two adjacent second refractive layers, and two of the third refractive layers are sandwiched between them on the outer sides, thereby jointly defining a bidirectional reciprocal module; Among them, the number of the bidirectional reciprocal modules included in the matching composite layer is at least M and they are stacked and connected to each other; wherein M is a positive integer, and M is greater than 3. A matching composite layer as described in claim 17, wherein any two adjacent bidirectional amplification modules share a third refractive layer; wherein N is further limited to be between 30 and 80. A matching composite layer as described in claim 17, wherein any two adjacent bidirectionally increasing modules share a third refractive layer having a common thickness; and each of the bidirectionally increasing modules has a module thickness; wherein the sum of the multiple common thicknesses of the multiple bidirectionally increasing modules is 20% to 25% of the sum of the multiple module thicknesses. A matching composite layer as described in claim 19, wherein any two adjacent bidirectionally recursive modules share a third refractive layer, and each of the bidirectionally recursive modules has a module thickness, and the sum of the module thicknesses of multiple bidirectionally recursive modules is 105% to 140% of the total thickness of the matching composite layer; wherein the module thickness of each of the bidirectionally recursive modules is between 320 nanometers and 380 nanometers.

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