JP2014160158A - Imaging lens, imaging apparatus, and portable terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact imaging lens which has sufficient brightness and has satisfactorily corrected various aberrations, and is composed of five lenses.SOLUTION: The imaging lens comprises, in order from an object side: a first lens L1 which has positive refractive power and has a convex surface facing the object side; a second lens L2 which has negative refractive power and has a shape in which the object-side surface thereof has a concave surface facing the object side and the image-side surface thereof has a convex surface facing an image side, or is infinite; a third lens L3 which has positive refractive power; a fourth lens L4 which has negative refractive power and has a concave surface facing the image side; and a fifth lens L5 which has positive refractive power and has a concave surface facing the image side. The image-side surface of the fifth lens L5 has an aspherical shape and has an inflection point in a position other than an intersection with an optical axis. The imaging lens satisfies the following conditional expressions: -0.60<f1/f45<-0.25 (1) and 0.1<f/f3<1.0 (2), where f1 is the focal length (mm) of the first lens L1, f45 is the composite focal length (mm) of the fourth lens L4 and the fifth lens L5, f is the focal length (mm) of the entire system of the imaging lens, and f3 is the focal length (mm) of the third lens L3.

Description

  The present invention relates to an imaging lens, and more particularly to an imaging lens that uses a solid-state imaging device such as a CCD type image sensor or a CMOS type image sensor to obtain a high resolution, an imaging device including the imaging lens, and a portable terminal.

  In recent years, portable terminals equipped with an imaging device using a solid-state imaging device such as a CCD (Charge Coupled Device) type image sensor or a CMOS (Complementary Metal Oxide Semiconductor) type image sensor have become widespread. In such an imaging apparatus mounted on a portable terminal, an apparatus using an imaging element having a high pixel number has been supplied to the market so that a higher quality image can be obtained. Conventional image pickup devices having a high number of pixels have been accompanied by an increase in size, but in recent years, pixels have become increasingly thinner and image pickup devices have become smaller. An imaging lens used for a highly thinned image sensor is required to have a high resolving power in order to cope with a highly thinned pixel. Since the resolving power of the lens is limited by the F value, a bright imaging lens having a small F value is required to obtain a high resolving power.

  An imaging lens used for such a high-definition imaging device is required to have a high resolving power, but sufficient performance cannot be obtained with an F value of about F2.8 as in the prior art. For this reason, a five-lens imaging lens has been proposed that can have a larger aperture ratio and higher performance than a four-lens configuration.

  As a five-lens imaging lens, in order from the object side, a first lens having positive refractive power, a second lens having negative refractive power, a third lens having positive refractive power, and a fourth lens having positive refractive power An imaging lens including a lens and a fifth lens having a negative refractive power is known (see Patent Document 1). In addition, a first lens having a positive refractive power, a second lens having a negative refractive power, a third lens having a positive refractive power, a fourth lens having a negative refractive power, and a positive refractive power in order from the object side. An imaging lens including a fifth lens having a lens is also known (see Patent Documents 2 to 4).

Japanese Patent No. 4858648 JP 2009-294527 JP 2009-294528 International Publication No. 2012/172781 Pamphlet

  However, the imaging lens described in Patent Document 1 is an imaging lens composed of a first lens having a positive refractive power and a fifth lens having a negative refractive power, and is advantageous for miniaturization because of a telephoto type. In order to improve the telecentric characteristics, the peripheral portion of the fifth lens has a positive refractive power, and the shapes of the central portion and the peripheral portion of the fifth lens are greatly different. Therefore, there is a problem that the manufacturing difficulty level is increased and manufacturing errors are likely to occur. The imaging lens described in Patent Document 2 can solve the problem of Patent Document 1 because the fifth lens has a positive refractive power, and is a bright imaging lens of about F2.3. There is a problem that the correction of distortion aberration is insufficient and the imaging lens has a long total length, so that the demand for high performance and miniaturization cannot be satisfied. In addition, the imaging lenses described in Patent Literature 3 and Patent Literature 4 cannot achieve performance suitable for a high-pixel-sized imaging device because of the brightness of about F2.8. Furthermore, there is a problem that the entire length of the imaging lens is long.

  In view of the above-described problems, the present invention provides a small imaging lens having a five-lens configuration that has sufficient brightness and that various aberrations are corrected favorably, an imaging device including the imaging lens, and the imaging device. An object is to provide a portable terminal equipped.

Here, although it is a scale of a small imaging lens, the present invention aims at miniaturization at a level satisfying the following expression. By satisfying this range, the entire imaging apparatus can be reduced in size and weight.
TL / 2Y <0.9 (9)
However,
TL: Distance on the optical axis from the lens surface closest to the object side to the image-side focal point of the entire imaging lens system 2Y: diagonal length of the imaging plane (diagonal length of the rectangular effective pixel area of the solid-state imaging device)
Here, the image-side focal point refers to an image point when a parallel light beam parallel to the optical axis is incident on the imaging lens.

When a parallel plate such as an optical low-pass filter, an infrared cut filter, or a seal glass of a solid-state image sensor package is disposed between the image-side surface of the imaging lens and the image-side focal position, the imaging lens is parallel. The flat plate portion is calculated as the TL value after the air conversion distance. More preferably, the range of the following formula is good.
TL / 2Y <0.8 (9) '

The imaging lens according to claim 1 is an imaging lens for forming a subject image on a photoelectric conversion unit of a solid-state imaging device, the imaging lens in order from the object side,
A first lens having a positive refractive power and having a convex surface facing the object side;
It has a negative refractive power, the object side surface has a concave surface facing the object side near the optical axis, and the image side surface has a convex surface toward the image side near the optical axis, or the curvature radius of the image side surface is infinite. The second lens,
A third lens having a positive refractive power;
A fourth lens having a negative refractive power and having a concave surface facing the image side in the vicinity of the optical axis;
A fifth lens having a positive refractive power and having a concave surface facing the image side in the vicinity of the optical axis;
The image side surface of the fifth lens has an aspherical shape, has an inflection point at a position other than the intersection with the optical axis, and satisfies the following conditional expression.
−0.60 <f1 / f45 <−0.25 (1)
0.1 <f / f3 <1.0 (2)
However,
f1: Focal length (mm) of the first lens
f45: Composite focal length (mm) of the fourth lens and the fifth lens
f: Focal length of the entire imaging lens system (mm)
f3: Focal length (mm) of the third lens

  The structure of the present invention for obtaining a small imaging lens with good aberration correction includes, in order from the object side, a first lens having a positive refractive power, a second lens having a negative refractive power, and a positive refractive power. The third lens has a negative refractive power, the fourth lens has a negative refractive power, and the fifth lens has a positive refractive power, and has a symmetrical power arrangement as a whole. It can be corrected and is advantageous. In general, when the fifth lens has a negative refracting power, it is necessary to weaken the negative refracting power or to have a positive refracting power at the periphery of the fifth lens in order to ensure telecentric characteristics. For this reason, the shape of the fifth lens changes greatly between the central portion and the peripheral portion, and manufacturing is likely to be difficult. However, in the present invention, the fifth lens has a positive refractive power, so that such a problem can be solved. Furthermore, the Petzval sum can be easily corrected by using two of the five lenses as negative lenses.

  In addition, since the first lens has a convex surface facing the object side, the principal point position of the optical system can be arranged on the object side, which is advantageous in reducing the overall length of the imaging lens. Furthermore, the second lens has a shape in which the object side surface is concave toward the object side, whereby the incident angle of the peripheral light beam to the second lens can be reduced, and the occurrence of astigmatism can be suppressed. . Furthermore, by making the side of the image convex toward the image side, or by making the radius of curvature of the image side infinite, the divergence of off-axis light flux can be suppressed and astigmatism and coma can be easily corrected. Can do.

  The fourth lens has a concave surface facing the image side, so that negative refractive power is arranged on the image side, and can be configured close to a so-called telephoto type, which is advantageous for downsizing the entire length of the imaging lens. become. Furthermore, since the image side surface of the fourth lens can have a diverging action, axial chromatic aberration can be corrected well.

  Further, the image side surface of the fifth lens has a concave surface directed toward the image side, so that the negative refracting power can be arranged most on the image side surface. The overall length of the lens can be reduced. Further, the image side surface of the fifth lens is aspherical and has an inflection point at a position other than the intersection with the optical axis, so that it becomes easy to ensure distortion correction and telecentric characteristics. The “inflection point” here refers to a point on the aspheric surface where the tangent plane of the aspherical vertex is a plane perpendicular to the optical axis in the curve of the lens cross-sectional shape within the effective radius (on the cross section in the optical axis direction). ).

Conditional expression (1) is a conditional expression for appropriately setting the ratio of the focal length of the first lens and the combined focal length of the fourth lens and the fifth lens. In the range of the conditional expression (1), the combined focal length of the fourth lens and the fifth lens becomes a negative value, and the entire imaging lens system has a telephoto type configuration, so that the overall length of the imaging lens can be shortened. Specifically, when the value of conditional expression (1) is below the upper limit, the negative refractive powers of the fourth lens and the fifth lens can be appropriately maintained, and the entire length of the imaging lens can be shortened. On the other hand, when the value of conditional expression (1) exceeds the lower limit, it is possible to suppress the negative refractive powers of the fourth lens and the fifth lens from becoming unnecessarily strong, and thus ensuring good telecentric characteristics. Will be able to. The range is preferably within the following formula.
−0.57 <f1 / f45 <−0.25 (1 ′)

Furthermore, in the present invention, the configuration from the first lens to the third lens is a combination of positive and negative (a lens having a positive refractive power, a lens having a negative refractive power, and a lens having a positive refractive power configuration. The same applies to the following). Therefore, when the value of conditional expression (2) is below the upper limit, the refractive power of the third lens does not become too strong, and spherical aberration and coma aberration can be corrected well. On the other hand, when the value of conditional expression (2) exceeds the lower limit, the refractive power of the third lens can be maintained moderately, the triplet type configured from the first lens to the third lens can be maintained, and the axis External aberration can be corrected satisfactorily. The range is preferably within the following formula.
0.15 <f / f3 <0.9 (2 ′)
Furthermore, it is desirably in the range of the following formula.
0.2 <f / f3 <0.85 (2 ")

  According to a second aspect of the present invention, there is provided the imaging lens according to the first aspect, wherein the third lens has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis.

  By making the third lens into a meniscus shape with the convex surface facing the image side, the object side surface becomes a shape with the concave surface facing the object side, and the incident angle of the peripheral luminous flux to the third lens can be reduced, Generation of astigmatism can be suppressed. In addition, the image side surface has a convex surface facing the image side, and the principal ray incident angle of the peripheral light beam can be reduced by the convergence effect of the surface, and the image is guided to the fourth lens while suppressing the refraction angle of off-axis light rays. Therefore, the off-axis aberration can be suppressed satisfactorily.

The imaging lens described in claim 3 is characterized in that, in the invention described in claim 1 or 2, the following conditional expression is satisfied.
0.05 <THIL3 / Σd <0.2 (3)
However,
THIL3: Thickness on the optical axis of the third lens (mm)
Σd: distance on the optical axis from the object side surface of the first lens to the image side surface of the fifth lens (mm)

Conditional expression (3) is a conditional expression for appropriately setting the thickness of the third lens. Since the value of conditional expression (3) exceeds the lower limit, the thickness on the optical axis of the third lens can be appropriately maintained, and the thickness of the peripheral portion of the third lens can be appropriately maintained, which is effective. It becomes easy to secure the flange thickness outside the diameter. On the other hand, when the value of conditional expression (3) is less than the upper limit, the thickness on the optical axis of the third lens does not become too large, and the clearance between the front and rear lenses of the third lens can be appropriately maintained, and the imaging lens The overall length can be shortened. The range is preferably within the following formula.
0.05 <THIL3 / Σd <0.17 (3 ′)
Furthermore, it is desirably in the range of the following formula.
0.05 <THIL3 / Σd <0.15 (3 ″)

The imaging lens of Claim 4 satisfies the following conditional expressions in the invention of any one of Claims 1-3.
0.2 <R1 / f <0.5 (4)
However,
R1: radius of curvature of object side surface of the first lens (mm)
f: Focal length of the entire imaging lens system (mm)

Conditional expression (4) is a conditional expression for appropriately setting the radius of curvature of the object side surface of the first lens to appropriately shorten the entire imaging lens and correct the aberration. When the value of conditional expression (4) is less than the upper limit, the refractive power of the object side surface of the first lens can be maintained moderately, the principal point of the first lens can be placed closer to the object side, and imaging is performed. The total lens length can be shortened. On the other hand, when the value of conditional expression (4) exceeds the lower limit, the refractive power of the object side surface of the first lens does not become excessively large, and higher-order spherical aberration and coma aberration that occur in the first lens are reduced. It can be kept small. The range is preferably within the following formula.
0.30 <R1 / f <0.5 (4 ′)
Furthermore, it is desirably in the range of the following formula.
0.36 <R1 / f <0.45 (4 ")
Furthermore, it is more desirable that the first lens has a meniscus shape with a convex surface facing the object side. Since the principal point position of the entire imaging lens can be moved closer to the object side, the overall length of the imaging lens can be shortened.

The imaging lens of Claim 5 satisfies the following conditional expressions in the invention in any one of Claims 1-4, It is characterized by the above-mentioned.
0.02 <THIL2 / Σd <0.12 (5)
However,
THIL2: thickness on the optical axis of the second lens (mm)
Σd: distance on the optical axis from the object side surface of the first lens to the image side surface of the fifth lens (mm)

Conditional expression (5) is a conditional expression for appropriately setting the thickness of the second lens on the optical axis. When the value of conditional expression (5) exceeds the lower limit, the thickness of the second lens does not become too thin, and the moldability can be prevented from being impaired. On the other hand, if the value of conditional expression (5) is less than the upper limit, the thickness of the second lens does not become too thick, and it is easy to secure the lens interval before and after the second lens, and as a result, the overall length of the imaging lens can be shortened. . The range is preferably within the following formula.
0.03 <THIL2 / Σd <0.11 (5 ′)

The imaging lens of Claim 6 satisfies the following conditional expressions in the invention in any one of Claims 1-5, It is characterized by the above-mentioned.
20 <ν5-ν4 <50 (6)
However,
ν5: Abbe number of the fifth lens ν4: Abbe number of the fourth lens

Conditional expression (6) is a conditional expression for satisfactorily correcting the chromatic aberration of the entire imaging lens system. When the value of conditional expression (6) exceeds the lower limit, chromatic aberrations such as axial chromatic aberration and lateral chromatic aberration can be corrected in a well-balanced manner. On the other hand, when the value of conditional expression (6) is lower than the upper limit, it can be made of an easily available material. The range is preferably within the following formula.
25 <ν5-ν4 <40 (6 ′)

The imaging lens of Claim 7 satisfies the following conditional expressions in the invention in any one of Claims 1-6, It is characterized by the above-mentioned.
0.2 <f / (2 × f1 × Fno) <0.4 (7)
However,
f: Focal length of the entire imaging lens system (mm)
f1: Focal length (mm) of the first lens
Fno: F-number of the entire imaging lens system

Conditional expression (7) defines the single numerical aperture NA of the first lens, and is a conditional expression for reducing the overall length of the imaging lens and performing good aberration correction. First, the meaning of conditional expression (7) will be described. The F number of the imaging lens is
Fno = f / D (10)
It can be expressed. However,
Fno: F number of the imaging lens f: focal length of the entire imaging lens system D: given by the entrance pupil diameter. Here, assuming that the focal length of the entire imaging lens system is normalized to 1 and the aperture stop is disposed in the vicinity of the first lens, the F number of the first lens unit is
FnoL1 = (f1 / f) / (1 / Fno) = f1 / (f × Fno) (11)
It becomes. here,
FnoL1: F number of the first lens unit f1: The focal length of the first lens, and the numerical aperture NA is NA = 1 / (2 × Fno). Therefore, the NA of the first lens unit is
NAL1 = 1 / (2 × (f1 / (f × Fno))) = f / (2 × f1 × Fno) (12)
However,
NAL1: The numerical aperture of the first lens unit.

When the value of conditional expression (7) is below the upper limit, the NA of the first lens unit does not become too large, and the spherical aberration that occurs in the first lens can be kept small. On the other hand, when the value of conditional expression (7) exceeds the lower limit, the refractive power of the first lens can be appropriately maintained, and downsizing of the entire length of the imaging lens can be achieved. The range is preferably within the following formula.
0.2 <f / (2 × f1 × Fno) <0.35 (7 ′)
Furthermore, it is desirably in the range of the following formula.
0.2 <f / (2 * f1 * Fno) <0.3 (7 ")

An imaging lens according to an eighth aspect of the invention according to any one of the first to seventh aspects satisfies the following conditional expression.
Σd / 2Y <0.6 (8)
However,
Σd: distance on the optical axis from the object side surface of the first lens to the image side surface of the fifth lens (mm)
2Y: Diagonal length of the imaging surface of the solid-state imaging device (mm)

When the value of conditional expression (8) is below the upper limit, a small imaging lens can be obtained. The range is preferably within the following formula.
0.4 <Σd / 2Y <0.57 (8 ′)

  An imaging lens according to a ninth aspect is the invention according to any one of the first to eighth aspects, further comprising a lens having substantially no power. That is, even when a dummy lens having substantially no refractive power is added to the configuration of claim 1, it is within the scope of application of the present invention.

  An imaging apparatus according to a tenth aspect includes the imaging lens according to any one of the first to ninth aspects and an imaging element.

  A portable terminal according to an eleventh aspect includes the imaging device according to the tenth aspect. By using the imaging device of the present invention, a smaller and higher performance portable terminal can be obtained.

  According to the present invention, a small imaging lens having a five-lens configuration, which has sufficient brightness and various aberrations are well corrected, an imaging device including the imaging lens, and a portable terminal including the imaging device Can be provided.

2 is a diagram schematically showing a cross section along the optical axis of an imaging optical system of the imaging apparatus 10. FIG. It is the front view (a) of the mobile phone to which the imaging device is applied, and the back view (b) of the mobile phone to which the imaging device is applied. It is a control block diagram of the smart phone of FIG. 3 is a cross-sectional view in the optical axis direction of the imaging lens of Example 1. FIG. Aberration diagrams of Example 1 (spherical aberration (a), astigmatism (b), distortion aberration (c). FIG. 6 is a cross-sectional view in the optical axis direction of the imaging lens of Example 2. FIG. 6 is an aberration diagram of Example 2 (spherical aberration (a), astigmatism (b), distortion (c)). 6 is a cross-sectional view in the optical axis direction of the imaging lens of Embodiment 3. FIG. FIG. 6 is an aberration diagram of Example 3 (spherical aberration (a), astigmatism (b), distortion (c)). 6 is a cross-sectional view in the optical axis direction of an imaging lens of Example 4. FIG. FIG. 6 is an aberration diagram of Example 4 (spherical aberration (a), astigmatism (b), distortion (c)). 6 is a cross-sectional view in the optical axis direction of the imaging lens of Example 5. FIG. FIG. 6 is an aberration diagram of Example 5 (spherical aberration (a), astigmatism (b), distortion (c)). 7 is a cross-sectional view in the optical axis direction of an imaging lens of Example 6. FIG. FIG. 10 is an aberration diagram of Example 6 (spherical aberration (a), astigmatism (b), distortion (c)). 10 is a cross-sectional view in the optical axis direction of an imaging lens of Example 7. FIG. 10 is an aberration diagram of Example 7 (spherical aberration (a), astigmatism (b), distortion (c)). FIG. 10 is a cross-sectional view in the optical axis direction of the imaging lens of Example 8. FIG. 10 is an aberration diagram of Example 8 (spherical aberration (a), astigmatism (b), distortion (c)).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view along the optical axis of the imaging apparatus 10 according to the present embodiment. The following configuration is a schematic diagram, and some shapes, dimensions, and the like are different from actual ones.

  As shown in FIG. 1, an imaging apparatus 10 includes a CMOS imaging device 11 as a solid-state imaging device including a photoelectric conversion unit 11 a and an imaging lens 12 that forms a subject image on the photoelectric conversion unit 11 a of the imaging device 11. A lens frame 13 that holds the imaging lens 12, an IR cut filter 14 that has a parallel plate shape, and a substrate 15 that supports the imaging element 11.

  As shown in FIG. 1, the image pickup device 11 is an image pickup device in which pixels (photoelectric conversion elements) are two-dimensionally arranged at the center of the light receiving side (upper surface in FIG. 1) on a parallel plate chip. A photoelectric conversion unit 11a as a surface is formed, and a signal processing circuit (not shown) is formed around the photoelectric conversion unit 11a. Such a signal processing circuit includes a drive circuit unit that sequentially drives each pixel to obtain a signal charge, an A / D conversion unit that converts each signal charge into a digital signal, and a signal that forms an image signal output using the digital signal. It consists of a processing unit and the like.

  In addition, a plurality of pads formed in the vicinity of the outer edge on the light receiving surface side of the chip of the image sensor 11 are connected to the substrate 15 by wires (not shown). The image sensor 11 converts the signal charge from the photoelectric conversion unit 11a into an image signal such as a digital YUV signal, and transmits the image signal to an external circuit (not shown) (for example, a control circuit included in a host device on which the image pickup device is mounted). It is like that. In addition, it is possible to receive power and a clock signal for driving the image sensor 11 from an external circuit. Here, Y is a luminance signal, U (= R−Y) is a color difference signal between red and the luminance signal, and V (= BY) is a color difference signal between blue and the luminance signal. Note that the image sensor is not limited to the above CMOS image sensor, and other devices such as a CCD may be used.

In FIG. 1, an imaging lens 12 having a five-lens configuration is provided inside a lens frame 13. The imaging lens 12 has, in order from the object side, a first lens L1 having a positive refractive power and a convex surface facing the object side, a negative refractive power, and the object side surface near the optical axis toward the object side. A second lens L2 having a concave surface and an image side surface having a convex surface facing the image side in the vicinity of the optical axis, or a third lens L3 having a positive refractive power; A fourth lens L4 having a negative refractive power and having a concave surface facing the image side near the optical axis, and a fourth lens L4 having a positive refractive power and a concave surface facing the image side near the optical axis. The image side surface of the fifth lens L5 has an aspherical shape, has an inflection point at a position other than the intersection with the optical axis, and satisfies the following conditional expression.
−0.60 <f1 / f45 <−0.25 (1)
0.1 <f / f3 <1.0 (2)
However,
f1: Focal length (mm) of the first lens L1
f45: Composite focal length (mm) of the fourth lens L4 and the fifth lens L5
f: Focal length of the entire imaging lens system (mm)
f3: focal length (mm) of the third lens L3

  An annular spacer SP is disposed between the lenses to maintain the distance between the lenses with high accuracy. Further, an IR cut filter 14 is disposed on the imaging element 11 side of the flange portion L5f of the fifth lens L5 via an annular spacer SP. The spacer SP that supports the IR cut filter 14 and the lower end of the lens frame 13 that holds the imaging lens 12 are in contact with the substrate 15.

  The operation of the imaging device 10 described above will be described. FIG. 2 shows a state in which the imaging device 10 is installed in a smartphone 100 as a mobile terminal. FIG. 3 is a control block diagram of the smartphone 100.

  In the imaging device 10, for example, the object side end surface of the lens frame 13 is provided on the back surface of the smartphone 100 (see FIG. 2B), and is disposed at a position corresponding to the lower side of the liquid crystal display unit.

  The imaging device 10 is connected to the control unit 101 of the smartphone 100 via an external connection terminal (an arrow in FIG. 3), and outputs an image signal such as a luminance signal or a color difference signal to the control unit 101 side.

  On the other hand, as shown in FIG. 3, the smartphone 100 controls each unit in an integrated manner, and a control unit (CPU) 101 that executes a program corresponding to each process, a switch such as a power source, a number, and the like using a touch pad. An input unit 60 for inputting instructions, and a display unit 65 for displaying captured images and the like in addition to predetermined data on a liquid crystal panel (however, the touch panel 70 serves as both the liquid crystal panel of the display unit and the touch pad of the input unit) And a wireless communication unit 80 for realizing various information communications with an external server, and a storage unit (ROM) storing necessary data such as a system program, various processing programs, and a terminal ID of the smartphone 100 91, various processing programs and data executed by the control unit 101, processing data, or an image obtained by the imaging device 10. And a temporary storage unit used as a work area for storing data and the like temporarily (RAM) and a 92.

  The smartphone 100 operates by operating the input key unit 60, drives the imaging lens 12 by an actuator (not shown) to perform an autofocus operation, and presses the release button 71 or the like to operate the imaging device 10. Imaging can be performed. The image signal input from the imaging device 10 is stored in the storage unit 92 or displayed on the touch panel 70 by the control system of the smartphone 100, and further transmitted to the outside as video information via the wireless communication unit 80. Is done.

Next, examples suitable for the above-described embodiment will be described. However, the present invention is not limited to the following examples.
f: Focal length of the entire imaging lens system fB: Back focus F: F number 2Y: Diagonal length 2ω on the imaging surface of the imaging device: Maximum field angle ENTP: Entrance pupil position (distance from the first surface to the entrance pupil position)
EXTP: exit pupil position (distance from imaging surface to exit pupil position)
H1: Front principal point position (distance from first surface to front principal point position)
H2: Rear principal point position (distance from the final surface to the rear principal point position)
R: radius of curvature D: spacing between axial upper surfaces Nd: refractive index νd of lens material with respect to d-line: Abbe number of lens material

  In each embodiment, the surface on which the aspheric coefficient is described is a surface having an aspheric shape, and the aspheric shape has an apex at the surface as an origin, an X axis in the optical axis direction, and a direction perpendicular to the optical axis. The height is expressed by the following “Equation 1” where h is the height.

ただし、
Ａｉ：ｉ次の非球面係数
Ｒ ：基準曲率半径
Ｋ ：円錐定数

However,
Ai: i-order aspheric coefficient R: reference radius of curvature K: conic constant

Regarding the meaning of the paraxial radius of curvature described in the claims and the examples, in the actual lens measurement scene, in the vicinity of the center of the lens (specifically, the central region within 10% of the lens outer diameter) ) Can be regarded as the paraxial curvature radius when fitting the shape measurement value in the least square method.
For example, when a secondary aspherical coefficient is used, a radius of curvature that takes into account the secondary aspherical coefficient in the reference curvature radius of the aspherical definition formula can be regarded as the paraxial curvature radius. (For example, refer to P41-42 of “Lens Design Method” written by Yoshiya Matsui (Kyoritsu Publishing Co., Ltd.) as a reference)

Example 1
Table 1 shows lens data of Example 1. In the following (including the lens data in the table), a power of 10 (for example, 2.5 × 10 ⁻⁰² ) is expressed using E (for example, 2.5E-02).

[Table 1]
Example 1

f = 3.6mm fB = 0.28mm F = 2.2 2Y = 5.8mm
ENTP = 0mm EXTP = -2.86mm H1 = -0.52mm H2 = -3.31mm

Surface number R (mm) D (mm) Nd νd Effective radius (mm)
1 (Aperture) ∞ -0.24 0.82
2 * 1.451 0.54 1.54470 56.2 0.83
3 * 5.217 0.37 0.86
4 * -3.575 0.15 1.63470 23.9 0.87
5 * -9.801 0.61 0.91
6 * -1.215 0.29 1.54470 56.2 1.11
7 * -0.959 0.09 1.21
8 * 2.280 0.34 1.63470 23.9 1.82
9 * 1.325 0.10 1.97
10 * 1.057 0.39 1.54470 56.2 2.25
11 * 1.138 0.90 2.39
12 ∞ 0.30 1.51630 64.2 2.72
13 ∞ 2.79

Aspheric coefficient

2nd surface 7th surface
K = -0.69435E + 00 K = -0.17530E + 01
A4 = 0.29719E-01 A4 = -0.27386E-01
A6 = 0.47463E-01 A6 = 0.31254E-01
A8 = -0.23860E + 00 A8 = -0.25082E-02
A10 = 0.40423E + 00 A10 = 0.10402E-01
A12 = 0.12872E-01 A12 = -0.21614E-02
A14 = -0.74699E + 00 A14 = -0.20878E-02
A16 = 0.48007E + 00 A16 = -0.38303E-03

3rd surface 8th surface
K = 0.31093E + 01 K = -0.30000E + 02
A4 = -0.29317E-01 A4 = -0.34187E-01
A6 = -0.10433E + 00 A6 = 0.54036E-02
A8 = 0.75017E-01 A8 = -0.29216E-02
A10 = -0.13511E + 00 A10 = 0.21198E-03
A12 = -0.16485E + 00 A12 = 0.37584E-05
A14 = 0.25456E + 00 A14 = -0.92477E-06
A16 = -0.57593E-01 A16 = 0.43586E-05

4th side 9th side
K = -0.92505E + 00 K = -0.30000E + 02
A4 = -0.63880E-01 A4 = -0.32831E-01
A6 = -0.13043E + 00 A6 = 0.19616E-02
A8 = -0.14981E-02 A8 = -0.13395E-02
A10 = 0.10873E + 00 A10 = 0.45430E-04
A12 = -0.83514E-01 A12 = 0.11556E-04
A14 = 0.40102E + 00 A14 = 0.11556E-05
A16 = -0.24897E + 00 A16 = -0.35795E-07

5th surface 10th surface
K = 0.23618E + 02 K = -0.17317E + 02
A4 = 0.47163E-01 A4 = -0.52141E-01
A6 = -0.49650E-01 A6 = 0.58317E-02
A8 = 0.44053E-01 A8 = 0.51924E-03
A10 = 0.70013E-01 A10 = -0.20370E-04
A12 = 0.12291E-01 A12 = -0.68787E-05
A14 = 0.45149E-01 A14 = -0.68953E-06
A16 = -0.78907E-03 A16 = 0.69641E-07

6th 11th
K = -0.56460E + 01 K = -0.78615E + 01
A4 = -0.85657E-01 A4 = -0.45509E-01
A6 = 0.12010E + 00 A6 = 0.66991E-02
A8 = -0.92750E-01 A8 = -0.61862E-03
A10 = 0.39891E-01 A10 = -0.70517E-05
A12 = -0.16385E-01 A12 = 0.35355E-05
A14 = 0.31309E-02 A14 = 0.73086E-06
A16 = -0.32607E-02 A16 = -0.60838E-07

Single lens data

Lens Start surface Focal length (mm)
1 2 3.51
2 4 -8.95
3 6 5.97
4 8 -5.78
5 10 10.11

  4 is a sectional view of the lens of Example 1. FIG. In the figure, L1 is a first lens having a positive refractive power and a convex surface facing the object side, L2 has a negative refractive power, and the object side surface is concave on the object side near the optical axis. The image side is a second lens having a convex surface toward the image side near the optical axis, L3 is a third lens having a positive refractive power, and L4 has a negative refractive power. The fourth lens L5 having a concave surface facing the image side near the optical axis is a fifth lens having a positive refractive power and a concave surface facing the image side near the optical axis. . S represents an aperture stop, and I represents an imaging surface. Further, F is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of a solid-state image sensor, or the like.

  FIG. 5 is an aberration diagram of Example 1 (spherical aberration (a), astigmatism (b), distortion (c)). In the following aberration diagrams, in the spherical aberration diagram, the solid line represents the d-line and the dotted line represents the g-line, and in the astigmatism diagram, the solid line S represents the sagittal image plane, and the dotted line M represents the meridional image plane. In this embodiment, the image side surface of the fifth lens L5 has an aspherical shape and has an inflection point at a position other than the intersection with the optical axis. The third lens L3 has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The first lens L1 has a meniscus shape with a convex surface facing the object side.

(Example 2)
Table 2 shows lens data of the imaging lens of Example 2.

[Table 2]
Example 2

f = 2.88mm fB = 0.13mm F = 2.4 2Y = 4.5mm
ENTP = 0mm EXTP = -2.29mm H1 = -0.55mm H2 = -2.75mm

Surface number R (mm) D (mm) Nd νd Effective radius (mm)
1 (Aperture) ∞ -0.16 0.60
2 * 1.143 0.39 1.54470 56.2 0.61
3 * 4.574 0.31 0.64
4 * -2.747 0.12 1.63470 23.9 0.65
5 * -8.000 0.45 0.70
6 * -1.155 0.27 1.54470 56.2 0.88
7 * -0.885 0.18 0.97
8 * 2.013 0.31 1.63470 23.9 1.46
9 * 0.835 0.04 1.62
10 * 0.645 0.31 1.54470 56.2 1.84
11 * 0.883 0.70 1.93
12 ∞ 0.30 1.51630 64.2 2.12
13 ∞ 2.19

Aspheric coefficient

2nd surface 7th surface
K = -0.72146E + 00 K = -0.17316E + 01
A4 = 0.55078E-01 A4 = -0.50878E-01
A6 = 0.14599E + 00 A6 = 0.10303E + 00
A8 = -0.11151E + 01 A8 = -0.42951E-02
A10 = 0.28676E + 01 A10 = 0.80169E-01
A12 = -0.42175E + 00 A12 = -0.28911E-01
A14 = -0.14090E + 02 A14 = -0.44351E-01
A16 = 0.14598E + 02 A16 = -0.12401E-01

3rd surface 8th surface
K = -0.61615E-01 K = -0.26472E + 02
A4 = -0.60728E-01 A4 = -0.75510E-01
A6 = -0.34610E + 00 A6 = 0.21785E-01
A8 = 0.31408E + 00 A8 = -0.12179E-01
A10 = -0.11493E + 01 A10 = 0.23531E-02
A12 = -0.20543E + 01 A12 = 0.17653E-03
A14 = 0.44990E + 01 A14 = -0.85641E-04
A16 = -0.16583E + 01 A16 = 0.23499E-04

4th side 9th side
K = -0.53423E + 00 K = -0.30000E + 02
A4 = -0.12707E + 00 A4 = -0.51645E-01
A6 = -0.38709E + 00 A6 = 0.33712E-02
A8 = -0.14325E-01 A8 = -0.49156E-02
A10 = 0.76860E + 00 A10 = 0.63867E-03
A12 = -0.10471E + 01 A12 = 0.83211E-04
A14 = 0.73947E + 01 A14 = 0.30887E-05
A16 = -0.58480E + 01 A16 = -0.15734E-05

5th surface 10th surface
K = -0.20389E + 02 K = -0.15421E + 02
A4 = 0.10543E + 00 A4 = -0.84311E-01
A6 = -0.16355E + 00 A6 = 0.15764E-01
A8 = 0.22030E + 00 A8 = 0.19327E-02
A10 = 0.57006E + 00 A10 = -0.15771E-03
A12 = 0.25279E + 00 A12 = -0.58927E-04
A14 = 0.94771E + 00 A14 = -0.78689E-05
A16 = -0.24238E + 00 A16 = 0.16032E-05

6th 11th
K = -0.73290E + 01 K = -0.65195E + 01
A4 = -0.15697E + 00 A4 = -0.76482E-01
A6 = 0.37130E + 00 A6 = 0.15709E-01
A8 = -0.43856E + 00 A8 = -0.19711E-02
A10 = 0.29492E + 00 A10 = 0.13091E-03
A12 = -0.20174E + 00 A12 = 0.40477E-04
A14 = 0.51109E-01 A14 = 0.86497E-05
A16 = -0.47809E-01 A16 = -0.30765E-05

Single lens data

Lens Start surface Focal length (mm)
1 2 2.69
2 4 -6.65
3 6 5.14
4 8 -2.50
5 10 3.01

  6 is a sectional view of the lens of Example 2. FIG. In the figure, L1 is a first lens having a positive refractive power and a convex surface facing the object side, L2 has a negative refractive power, and the object side surface is concave on the object side near the optical axis. The image side is a second lens having a convex surface toward the image side near the optical axis, L3 is a third lens having a positive refractive power, and L4 has a negative refractive power. The fourth lens L5 having a concave surface facing the image side near the optical axis is a fifth lens having a positive refractive power and a concave surface facing the image side near the optical axis. . S represents an aperture stop, and I represents an imaging surface. Further, F is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of a solid-state image sensor, or the like.

  FIG. 7 is an aberration diagram of Example 2 (spherical aberration (a), astigmatism (b), distortion (c)). In this embodiment, the image side surface of the fifth lens L5 has an aspherical shape and has an inflection point at a position other than the intersection with the optical axis. The third lens L3 has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The first lens L1 has a meniscus shape with a convex surface facing the object side.

(Example 3)
Table 3 shows lens data of the imaging lens of Example 3.

[Table 3]
Example 3

f = 3.59mm fB = 0.13mm F = 2.04 2Y = 5.8mm
ENTP = 0mm EXTP = -2.81mm H1 = -0.79mm H2 = -3.46mm

Surface number R (mm) D (mm) Nd νd Effective radius (mm)
1 (Aperture) ∞ -0.26 0.88
2 * 1.486 0.64 1.54470 56.2 0.91
3 * 5.836 0.35 0.94
4 * -3.604 0.20 1.63470 23.9 0.94
5 * -6.199 0.52 0.95
6 * -1.179 0.30 1.54470 56.2 1.12
7 * -1.055 0.05 1.26
8 * 2.052 0.40 1.63470 23.9 1.70
9 * 1.266 0.16 1.99
10 * 1.167 0.43 1.54470 56.2 2.23
11 * 1.291 0.90 2.34
12 ∞ 0.30 1.51630 64.2 2.78
13 ∞ 2.84

Aspheric coefficient

2nd surface 7th surface
K = -0.74695E + 00 K = -0.21793E + 01
A4 = 0.27818E-01 A4 = -0.97965E-02
A6 = 0.39760E-01 A6 = 0.39464E-01
A8 = -0.24455E + 00 A8 = 0.19959E-03
A10 = 0.42177E + 00 A10 = 0.11266E-01
A12 = 0.37587E-01 A12 = -0.18920E-02
A14 = -0.73643E + 00 A14 = -0.19948E-02
A16 = 0.46074E + 00 A16 = -0.26926E-03

3rd surface 8th surface
K = 0.31658E + 01 K = -0.30000E + 02
A4 = -0.30619E-01 A4 = -0.47514E-01
A6 = -0.10467E + 00 A6 = 0.67460E-02
A8 = 0.81265E-01 A8 = -0.34206E-02
A10 = -0.12469E + 00 A10 = 0.87284E-04
A12 = -0.14417E + 00 A12 = 0.14739E-04
A14 = 0.26306E + 00 A14 = 0.11590E-04
A16 = -0.68061E-01 A16 = 0.72662E-05

4th side 9th side
K = 0.29954E + 00 K = -0.19707E + 02
A4 = -0.67367E-01 A4 = -0.34435E-01
A6 = -0.11856E + 00 A6 = 0.68884E-03
A8 = 0.42311E-02 A8 = -0.97500E-03
A10 = 0.10844E + 00 A10 = 0.10904E-03
A12 = -0.82652E-01 A12 = 0.50098E-05
A14 = 0.39568E + 00 A14 = -0.44825E-05
A16 = -0.26514E + 00 A16 = 0.38179E-06

5th surface 10th surface
K = 0.25635E + 02 K = -0.14560E + 02
A4 = 0.40834E-01 A4 = -0.74404E-01
A6 = -0.48788E-01 A6 = 0.78732E-02
A8 = 0.45768E-01 A8 = 0.92110E-03
A10 = 0.67899E-01 A10 = -0.42068E-04
A12 = 0.32107E-02 A12 = -0.13947E-04
A14 = 0.38144E-01 A14 = -0.11589E-05
A16 = 0.94667E-02 A16 = 0.20815E-06

6th 11th
K = -0.67420E + 01 K = -0.87695E + 01
A4 = -0.59360E-01 A4 = -0.59396E-01
A6 = 0.11679E + 00 A6 = 0.71483E-02
A8 = -0.95891E-01 A8 = -0.68024E-03
A10 = 0.41553E-01 A10 = -0.90748E-05
A12 = -0.13357E-01 A12 = 0.54719E-05
A14 = 0.50836E-02 A14 = 0.94876E-06
A16 = -0.25760E-02 A16 = -0.92397E-07

Single lens data

Lens Start surface Focal length (mm)
1 2 3.48
2 4 -13.98
3 6 9.94
4 8 -6.49
5 10 10.03

  FIG. 8 is a sectional view of the lens of Example 3. In the figure, L1 is a first lens having a positive refractive power and a convex surface facing the object side, L2 has a negative refractive power, and the object side surface is concave on the object side near the optical axis. The image side is a second lens having a convex surface toward the image side near the optical axis, L3 is a third lens having a positive refractive power, and L4 has a negative refractive power. The fourth lens L5 having a concave surface facing the image side near the optical axis is a fifth lens having a positive refractive power and a concave surface facing the image side near the optical axis. . S represents an aperture stop, and I represents an imaging surface. Further, F is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of a solid-state image sensor, or the like.

  FIG. 9 is an aberration diagram of Example 3 (spherical aberration (a), astigmatism (b), distortion (c)). In this embodiment, the image side surface of the fifth lens L5 has an aspherical shape and has an inflection point at a position other than the intersection with the optical axis. The third lens L3 has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The first lens L1 has a meniscus shape with a convex surface facing the object side.

Example 4
Table 4 shows lens data of the imaging lens of Example 4.

[Table 4]
Example 4

f = 3.6mm fB = 0.15mm F = 2.4 2Y = 5.8mm
ENTP = 0mm EXTP = -2.94mm H1 = -0.6mm H2 = -3.45mm

Surface number R (mm) D (mm) Nd νd Effective radius (mm)
1 (Aperture) ∞ -0.18 0.75
2 * 1.450 0.48 1.54470 56.2 0.78
3 * 5.865 0.39 0.82
4 * -3.382 0.15 1.63470 23.9 0.84
5 * -10.000 0.56 0.89
6 * -1.561 0.38 1.54470 56.2 1.12
7 * -1.138 0.19 1.25
8 * 3.154 0.47 1.60700 26.6 1.87
9 * 1.451 0.06 2.10
10 * 1.122 0.43 1.54470 56.2 2.39
11 * 1.280 0.90 2.54
12 ∞ 0.30 1.53110 62.5 2.77
13 ∞ 2.84

Aspheric coefficient

2nd surface 7th surface
K = -0.71727E + 00 K = -0.16794E + 01
A4 = 0.28449E-01 A4 = -0.28287E-01
A6 = 0.47364E-01 A6 = 0.32812E-01
A8 = -0.23611E + 00 A8 = -0.11839E-02
A10 = 0.38356E + 00 A10 = 0.10807E-01
A12 = -0.35206E-01 A12 = -0.23927E-02
A14 = -0.77107E + 00 A14 = -0.23172E-02
A16 = 0.51433E + 00 A16 = -0.34120E-03

3rd surface 8th surface
K = -0.98860E-01 K = -0.29406E + 02
A4 = -0.31114E-01 A4 = -0.33640E-01
A6 = -0.11317E + 00 A6 = 0.72216E-02
A8 = 0.64322E-01 A8 = -0.26240E-02
A10 = -0.15444E + 00 A10 = 0.29690E-03
A12 = -0.17445E + 00 A12 = 0.12559E-04
A14 = 0.25166E + 00 A14 = -0.46890E-05
A16 = -0.58774E-01 A16 = 0.96596E-06

4th side 9th side
K = -0.57814E + 00 K = -0.29708E + 02
A4 = -0.64789E-01 A4 = -0.25806E-01
A6 = -0.12916E + 00 A6 = 0.14488E-02
A8 = -0.50244E-02 A8 = -0.97627E-03
A10 = 0.10156E + 00 A10 = 0.88527E-04
A12 = -0.89471E-01 A12 = 0.64145E-05
A14 = 0.41092E + 00 A14 = -0.33264E-08
A16 = -0.20449E + 00 A16 = -0.41920E-07

5th surface 10th surface
K = -0.92153E + 01 K = -0.16533E + 02
A4 = 0.52871E-01 A4 = -0.42519E-01
A6 = -0.53058E-01 A6 = 0.52370E-02
A8 = 0.46514E-01 A8 = 0.39230E-03
A10 = 0.76663E-01 A10 = -0.22845E-04
A12 = 0.19269E-01 A12 = -0.53226E-05
A14 = 0.48741E-01 A14 = -0.47977E-06
A16 = -0.15463E-01 A16 = 0.60440E-07

6th 11th
K = -0.73195E + 01 K = -0.66740E + 01
A4 = -0.79684E-01 A4 = -0.36347E-01
A6 = 0.12262E + 00 A6 = 0.49663E-02
A8 = -0.90804E-01 A8 = -0.42581E-03
A10 = 0.40639E-01 A10 = 0.15685E-04
A12 = -0.16587E-01 A12 = 0.32796E-05
A14 = 0.31422E-02 A14 = 0.48653E-06
A16 = -0.17542E-02 A16 = -0.10836E-06

Single lens data

Lens Start surface Focal length (mm)
1 2 3.41
2 4 -8.12
3 6 5.86
4 8 -4.94
5 10 8.52

  FIG. 10 is a sectional view of the lens of Example 4. In the figure, L1 is a first lens having a positive refractive power and a convex surface facing the object side, L2 has a negative refractive power, and the object side surface is concave on the object side near the optical axis. The image side is a second lens having a convex surface toward the image side near the optical axis, L3 is a third lens having a positive refractive power, and L4 has a negative refractive power. The fourth lens L5 having a concave surface facing the image side near the optical axis is a fifth lens having a positive refractive power and a concave surface facing the image side near the optical axis. . S represents an aperture stop, and I represents an imaging surface. Further, F is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of a solid-state image sensor, or the like.

  FIG. 11 is an aberration diagram of Example 4 (spherical aberration (a), astigmatism (b), distortion (c)). In this embodiment, the image side surface of the fifth lens L5 has an aspherical shape and has an inflection point at a position other than the intersection with the optical axis. The third lens L3 has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The first lens L1 has a meniscus shape with a convex surface facing the object side.

(Example 5)
Table 5 shows lens data of the imaging lens of Example 5.

[Table 5]
Example 5

f = 3.6mm fB = 0.13mm F = 2.39 2Y = 5.8mm
ENTP = 0mm EXTP = -3.09mm H1 = -0.42mm H2 = -3.46mm

Surface number R (mm) D (mm) Nd νd Effective radius (mm)
1 (Aperture) ∞ -0.17 0.75
2 * 1.538 0.50 1.54470 56.2 0.77
3 * 7.527 0.41 0.83
4 * -3.206 0.23 1.63200 23.4 0.85
5 * -10.000 0.54 0.94
6 * -1.544 0.44 1.54470 56.2 1.13
7 * -1.039 0.15 1.27
8 * 2.720 0.40 1.60700 26.6 2.12
9 * 1.288 0.07 2.26
10 * 1.031 0.40 1.54470 56.2 2.49
11 * 1.094 1.00 2.55
12 ∞ 0.30 1.51630 64.2 2.77
13 ∞ 2.84

Aspheric coefficient

2nd surface 7th surface
K = -0.85100E + 00 K = -0.17648E + 01
A4 = 0.22647E-01 A4 = -0.35136E-01
A6 = 0.43208E-01 A6 = 0.27034E-01
A8 = -0.23817E + 00 A8 = -0.27109E-02
A10 = 0.37122E + 00 A10 = 0.10694E-01
A12 = -0.46048E-01 A12 = -0.22260E-02
A14 = -0.72910E + 00 A14 = -0.21018E-02
A16 = 0.51363E + 00 A16 = -0.19282E-04

3rd surface 8th surface
K = -0.10647E + 02 K = -0.30000E + 02
A4 = -0.34588E-01 A4 = -0.20149E-01
A6 = -0.11820E + 00 A6 = 0.82413E-02
A8 = 0.73424E-01 A8 = -0.24959E-02
A10 = -0.14291E + 00 A10 = 0.31042E-03
A12 = -0.16544E + 00 A12 = 0.12334E-04
A14 = 0.25032E + 00 A14 = -0.58206E-05
A16 = -0.73009E-01 A16 = 0.39675E-06

4th side 9th side
K = 0.33103E-01 K = -0.27063E + 02
A4 = -0.66774E-01 A4 = -0.14428E-01
A6 = -0.13351E + 00 A6 = 0.17604E-02
A8 = -0.12372E-01 A8 = -0.92503E-03
A10 = 0.87692E-01 A10 = 0.10844E-03
A12 = -0.10801E + 00 A12 = 0.98858E-05
A14 = 0.38983E + 00 A14 = 0.13633E-07
A16 = -0.18741E + 00 A16 = -0.23772E-06

5th surface 10th surface
K = 0.51360E + 01 K = -0.16132E + 02
A4 = 0.50472E-01 A4 = -0.32706E-01
A6 = -0.63216E-01 A6 = 0.40298E-02
A8 = 0.25239E-01 A8 = 0.36324E-03
A10 = 0.50051E-01 A10 = -0.21986E-04
A12 = -0.15304E-02 A12 = -0.40066E-05
A14 = 0.40427E-01 A14 = -0.34129E-06
A16 = -0.12350E-01 A16 = 0.56197E-07

6th 11th
K = -0.77068E + 01 K = -0.64103E + 01
A4 = -0.88493E-01 A4 = -0.36855E-01
A6 = 0.12033E + 00 A6 = 0.54664E-02
A8 = -0.92181E-01 A8 = -0.30479E-03
A10 = 0.39494E-01 A10 = 0.59347E-05
A12 = -0.17033E-01 A12 = 0.31053E-07
A14 = 0.33444E-02 A14 = 0.48565E-06
A16 = -0.13394E-02 A16 = -0.54269E-07

Single lens data

Lens Start surface Focal length (mm)
1 2 3.45
2 4 -7.57
3 6 4.46
4 8 -4.51
5 10 10.15

  12 is a sectional view of the lens of Example 5. FIG. In the figure, L1 is a first lens having a positive refractive power and a convex surface facing the object side, L2 has a negative refractive power, and the object side surface is concave on the object side near the optical axis. The image side is a second lens having a convex surface toward the image side near the optical axis, L3 is a third lens having a positive refractive power, and L4 has a negative refractive power. The fourth lens L5 having a concave surface facing the image side near the optical axis is a fifth lens having a positive refractive power and a concave surface facing the image side near the optical axis. . S represents an aperture stop, and I represents an imaging surface. Further, F is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of a solid-state image sensor, or the like.

  FIG. 13 is an aberration diagram of Example 5 (spherical aberration (a), astigmatism (b), distortion (c)). In this embodiment, the image side surface of the fifth lens L5 has an aspherical shape and has an inflection point at a position other than the intersection with the optical axis. The third lens L3 has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The first lens L1 has a meniscus shape with a convex surface facing the object side.

(Example 6)
Table 6 shows lens data of the imaging lens of Example 6.

[Table 6]
Example 6

f = 3.6mm fB = 0.14mm F = 2.4 2Y = 5.8mm
ENTP = 0mm EXTP = -3.09mm H1 = -0.41mm H2 = -3.46mm

Surface number R (mm) D (mm) Nd νd Effective radius (mm)
1 (Aperture) ∞ -0.17 0.75
2 * 1.542 0.47 1.54470 56.2 0.77
3 * 6.873 0.45 0.82
4 * -3.330 0.25 1.65000 21.4 0.86
5 * -9.423 0.57 0.96
6 * -1.272 0.35 1.54470 56.2 1.13
7 * -0.947 0.11 1.23
8 * 2.626 0.40 1.65000 21.4 2.09
9 * 1.374 0.07 2.24
10 * 1.078 0.45 1.54470 56.2 2.41
11 * 1.143 1.00 2.50
12 ∞ 0.30 1.51630 64.2 2.76
13 ∞ 2.83

Aspheric coefficient

2nd surface 7th surface
K = -0.86932E + 00 K = -0.17005E + 01
A4 = 0.21966E-01 A4 = -0.38067E-01
A6 = 0.43267E-01 A6 = 0.26347E-01
A8 = -0.24290E + 00 A8 = -0.26213E-02
A10 = 0.37149E + 00 A10 = 0.10750E-01
A12 = -0.36892E-01 A12 = -0.22049E-02
A14 = -0.73268E + 00 A14 = -0.23304E-02
A16 = 0.51363E + 00 A16 = -0.57314E-03

3rd surface 8th surface
K = -0.66472E + 01 K = -0.28594E + 02
A4 = -0.32843E-01 A4 = -0.20729E-01
A6 = -0.11044E + 00 A6 = 0.81009E-02
A8 = 0.75390E-01 A8 = -0.24620E-02
A10 = -0.13664E + 00 A10 = 0.31231E-03
A12 = -0.16222E + 00 A12 = 0.11705E-04
A14 = 0.23380E + 00 A14 = -0.58420E-05
A16 = -0.71481E-01 A16 = 0.41152E-06

4th side 9th side
K = 0.41002E + 00 K = -0.30000E + 02
A4 = -0.68452E-01 A4 = -0.17454E-01
A6 = -0.13313E + 00 A6 = 0.27300E-02
A8 = -0.27080E-02 A8 = -0.89841E-03
A10 = 0.92120E-01 A10 = 0.10944E-03
A12 = -0.11083E + 00 A12 = 0.94472E-05
A14 = 0.36810E + 00 A14 = -0.11755E-06
A16 = -0.18566E + 00 A16 = -0.30624E-06

5th surface 10th surface
K = 0.30000E + 02 K = -0.17872E + 02
A4 = 0.42131E-01 A4 = -0.33743E-01
A6 = -0.60828E-01 A6 = 0.40567E-02
A8 = 0.22536E-01 A8 = 0.39007E-03
A10 = 0.43083E-01 A10 = -0.22056E-04
A12 = -0.64358E-02 A12 = -0.44547E-05
A14 = 0.38792E-01 A14 = -0.40427E-06
A16 = -0.72878E-02 A16 = 0.59122E-07

6th 11th
K = -0.56210E + 01 K = -0.70101E + 01
A4 = -0.88723E-01 A4 = -0.35765E-01
A6 = 0.11878E + 00 A6 = 0.56829E-02
A8 = -0.94002E-01 A8 = -0.45224E-03
A10 = 0.39018E-01 A10 = -0.82503E-05
A12 = -0.16587E-01 A12 = 0.23369E-05
A14 = 0.31178E-02 A14 = 0.69733E-06
A16 = -0.27194E-02 A16 = -0.64435E-07

Single lens data

Lens Start surface Focal length (mm)
1 2 3.54
2 4 -8.05
3 6 4.93
4 8 -5.07
5 10 10.11

  FIG. 14 is a sectional view of the lens of Example 6. In the figure, L1 is a first lens having a positive refractive power and a convex surface facing the object side, L2 has a negative refractive power, and the object side surface is concave on the object side near the optical axis. The image side is a second lens having a convex surface toward the image side near the optical axis, L3 is a third lens having a positive refractive power, and L4 has a negative refractive power. The fourth lens L5 having a concave surface facing the image side near the optical axis is a fifth lens having a positive refractive power and a concave surface facing the image side near the optical axis. . S represents an aperture stop, and I represents an imaging surface. Further, F is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of a solid-state image sensor, or the like.

  FIG. 15 is an aberration diagram of Example 6 (spherical aberration (a), astigmatism (b), distortion (c)). In this embodiment, the image side surface of the fifth lens L5 has an aspherical shape and has an inflection point at a position other than the intersection with the optical axis. The third lens L3 has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The first lens L1 has a meniscus shape with a convex surface facing the object side.

(Example 7)
Table 7 shows lens data of the imaging lens of Example 7.

[Table 7]
Example 7

f = 2.97mm fB = 0.16mm F = 2.4 2Y = 4.5mm
ENTP = 0mm EXTP = -2.02mm H1 = -1.09mm H2 = -2.81mm

Surface number R (mm) D (mm) Nd νd Effective radius (mm)
1 (Aperture) ∞ -0.15 0.62
2 * 1.206 0.42 1.54470 56.2 0.62
3 * 33.159 0.12 0.66
4 * -3.696 0.24 1.63470 23.9 0.66
5 * -16.166 0.26 0.70
6 * -5.956 0.19 1.54470 56.2 0.73
7 * -2.830 0.17 0.79
8 * -2.845 0.53 1.63470 23.9 0.85
9 * 8.236 0.12 1.30
10 * 0.981 0.61 1.54470 56.2 1.57
11 * 1.060 0.60 1.78
12 ∞ 0.18 1.51630 64.1 2.11
13 ∞ 2.16

Aspheric coefficient

2nd surface 7th surface
K = -0.59722E + 00 K = 0.10420E + 02
A4 = 0.57732E-02 A4 = 0.10463E + 01
A6 = 0.40053E-01 A6 = -0.59182E + 01
A8 = -0.56088E + 00 A8 = 0.17286E + 02
A10 = 0.89438E + 00 A10 = -0.33149E + 02
A12 = -0.55052E + 00 A12 = 0.35818E + 02
A14 = -0.30495E + 01 A14 = -0.13881E + 02

3rd surface 8th surface
K = -0.10854E + 02 K = -0.29687E + 02
A4 = -0.20562E + 00 A4 = 0.92558E + 00
A6 = -0.84893E-01 A6 = -0.40901E + 01
A8 = 0.29531E + 00 A8 = 0.99010E + 01
A10 = -0.22693E + 01 A10 = -0.17335E + 02
A12 = 0.96656E + 00 A12 = 0.16787E + 02
A14 = 0.20015E + 01 A14 = -0.66444E + 01

4th side 9th side
K = 0.23712E + 02 K = 0.24774E + 02
A4 = -0.14932E + 00 A4 = -0.18129E + 00
A6 = 0.39750E + 00 A6 = 0.45005E + 00
A8 = 0.11453E + 01 A8 = -0.83817E + 00
A10 = -0.68729E + 01 A10 = 0.72232E + 00
A12 = 0.10687E + 02 A12 = -0.28808E + 00
A14 = -0.22716E + 01 A14 = 0.43514E-01

5th surface 10th surface
K = 0.30000E + 02 K = -0.53948E + 01
A4 = -0.86700E-01 A4 = -0.36790E + 00
A6 = 0.13000E + 00 A6 = 0.25446E + 00
A8 = 0.23800E + 01 A8 = -0.16628E + 00
A10 = -0.10660E + 02 A10 = 0.92591E-01
A12 = 0.18953E + 02 A12 = -0.27438E-01
A14 = -0.12886E + 02 A14 = 0.31348E-02

6th 11th
K = 0.58984E + 02 K = -0.19102E + 01
A4 = 0.20864E + 00 A4 = -0.39720E + 00
A6 = -0.35245E + 01 A6 = 0.32425E + 00
A8 = 0.15502E + 02 A8 = -0.21209E + 00
A10 = -0.41966E + 02 A10 = 0.88368E-01
A12 = 0.61038E + 02 A12 = -0.20621E-01
A14 = -0.33886E + 02 A14 = 0.20185E-02

Single lens data

Lens Start surface Focal length (mm)
1 2 2.29
2 4 -7.61
3 6 9.69
4 8 -3.27
5 10 6.49

  FIG. 16 is a sectional view of the lens of Example 7. In the figure, L1 is a first lens having a positive refractive power and a convex surface facing the object side, L2 has a negative refractive power, and the object side surface is concave on the object side near the optical axis. The image side is a second lens having a convex surface toward the image side near the optical axis, L3 is a third lens having a positive refractive power, and L4 has a negative refractive power. The fourth lens L5 having a concave surface facing the image side near the optical axis is a fifth lens having a positive refractive power and a concave surface facing the image side near the optical axis. . S represents an aperture stop, and I represents an imaging surface. Further, F is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of a solid-state image sensor, or the like.

  FIG. 17 is an aberration diagram of Example 7 (spherical aberration (a), astigmatism (b), distortion (c)). In this embodiment, the image side surface of the fifth lens L5 has an aspherical shape and has an inflection point at a position other than the intersection with the optical axis. The third lens L3 has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The first lens L1 has a meniscus shape with a convex surface facing the object side.

(Example 8)
Table 8 shows lens data of the imaging lens of Example 8.

[Table 8]
Example 8

f = 2.72mm fB = 0.1mm F = 2.3 2Y = 4.5mm
ENTP = 0mm EXTP = -2.21mm H1 = -0.48mm H2 = -2.62mm

Surface number R (mm) D (mm) Nd νd Effective radius (mm)
1 (Aperture) ∞ -0.15 0.59
2 * 1.154 0.37 1.54470 56.2 0.62
3 * 4.564 0.26 0.64
4 * -4.530 0.12 1.64000 23.3 0.64
5 * ∞ 0.40 0.70
6 * -2.431 0.34 1.54470 56.2 0.78
7 * -1.347 0.09 0.92
8 * 7.957 0.17 1.64000 23.3 1.24
9 * 2.076 0.22 1.41
10 * 1.008 0.67 1.53050 55.7 1.76
11 * 1.083 0.50 2.01
12 ∞ 0.30 1.51630 64.2 2.16
13 ∞ 2.22

Aspheric coefficient

2nd surface 7th surface
K = 0.40987E + 00 K = 0.84966E + 00
A4 = 0.70534E-03 A4 = -0.14432E + 00
A6 = -0.89973E-02 A6 = 0.28105E + 00
A8 = 0.94982E-01 A8 = -0.75778E-01
A10 = -0.75851E-01 A10 = -0.13146E + 00
A12 = -0.80642E + 00 A12 = 0.16471E + 00

3rd surface 8th surface
K = 0.51449E + 01 K = 0.27882E + 02
A4 = -0.21246E-02 A4 = 0.56667E-01
A6 = -0.14469E + 00 A6 = -0.10502E + 00
A8 = -0.26000E-01 A8 = 0.23464E-01
A10 = 0.19416E + 00 A10 = -0.66291E-02
A12 = -0.29527E + 01 A12 = -0.12780E-01
A14 = 0.53447E-02

4th side 9th side
K = 0.26964E + 02 K = -0.26088E + 02
A4 = -0.80502E-01 A4 = 0.24555E-02
A6 = -0.14521E + 00 A6 = -0.28313E-01
A8 = -0.26954E + 00 A8 = -0.12326E-01
A10 = -0.64051E + 00 A10 = -0.40165E-02
A12 = -0.80769E + 00 A12 = 0.58886E-02
A14 = -0.11259E-02

5th surface 10th surface
K = -0.15000E + 02 K = -0.51664E + 01
A4 = 0.10040E-01 A4 = -0.14403E + 00
A6 = 0.96773E-01 A6 = -0.85614E-02
A8 = -0.32571E + 00 A8 = 0.18634E-01
A10 = -0.20901E + 00 A10 = 0.22288E-02
A12 = 0.74575E + 00 A12 = -0.11350E-02
A14 = -0.47309E-03
A16 = 0.11907E-03

6th 11th
K = 0.86229E + 01 K = -0.73043E + 00
A4 = -0.20962E + 00 A4 = -0.31543E + 00
A6 = 0.35252E + 00 A6 = 0.10990E + 00
A8 = -0.49232E-01 A8 = -0.30808E-01
A10 = -0.24414E + 00 A10 = 0.84943E-03
A12 = 0.19320E + 00 A12 = 0.82198E-03
A14 = 0.66399E-04
A16 = -0.36832E-04

Single lens data

Lens Start surface Focal length (mm)
1 2 2.73
2 4 -7.08
3 6 4.99
4 8 -4.44
5 10 6.70

  FIG. 18 is a sectional view of the lens of Example 8. In the figure, L1 is a first lens having a positive refractive power and a convex surface facing the object side, L2 has a negative refractive power, and the object side surface is concave on the object side near the optical axis. The image side surface is a second lens having an infinite radius of curvature of the image side surface, L3 is a third lens having a positive refractive power, L4 has a negative refractive power, and the optical axis A fourth lens L5 having a concave surface facing the image side in the vicinity, L5, has a positive refractive power and is a fifth lens having a concave surface facing the image side in the vicinity of the optical axis. S represents an aperture stop, and I represents an imaging surface. Further, F is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of a solid-state image sensor, or the like.

  FIG. 19 is an aberration diagram of Example 8 (spherical aberration (a), astigmatism (b), distortion (c)). In this embodiment, the image side surface of the fifth lens L5 has an aspherical shape and has an inflection point at a position other than the intersection with the optical axis. The third lens L3 has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The first lens L1 has a meniscus shape with a convex surface facing the object side.

  Table 9 shows values of the respective examples corresponding to the respective conditional expressions.

  Further, the present invention is not limited to the embodiments described in the specification, and it is understood that other embodiments and modifications are included in the art from the embodiments and ideas described in the present specification. It is obvious to For example, even when a dummy lens having substantially no refractive power is further provided, it is within the scope of application of the present invention.

  The present invention can provide an imaging lens suitable for a small portable terminal.

DESCRIPTION OF SYMBOLS 10 Imaging device 11a Photoelectric conversion part 11 Imaging element 12 Imaging lens 13 Mirror frame 15 Substrate 60 Input key part 65 Display part 70 Touch panel 71 Release button 80 Wireless communication part 92 Memory | storage part 100 Smartphone 101 Control part I Imaging surface F Parallel flat plate L1- L5 Lens S Aperture stop SP Spacer

Claims (11)

An imaging lens for forming a subject image on a photoelectric conversion unit of a solid-state imaging device, the imaging lens in order from the object side,
A first lens having a positive refractive power and having a convex surface facing the object side;
It has a negative refractive power, the object side surface has a concave surface facing the object side near the optical axis, and the image side surface has a convex surface toward the image side near the optical axis, or the curvature radius of the image side surface is infinite. The second lens,
A third lens having a positive refractive power;
A fourth lens having a negative refractive power and having a concave surface facing the image side in the vicinity of the optical axis;
A fifth lens having a positive refractive power and having a concave surface facing the image side in the vicinity of the optical axis;
An image pickup lens, wherein the image side surface of the fifth lens has an aspherical shape, has an inflection point at a position other than the intersection with the optical axis, and satisfies the following conditional expression.
−0.60 <f1 / f45 <−0.25 (1)
0.1 <f / f3 <1.0 (2)
However,
f1: Focal length (mm) of the first lens
f45: Composite focal length (mm) of the fourth lens and the fifth lens
f: Focal length of the entire imaging lens system (mm)
f3: Focal length (mm) of the third lens   The imaging lens according to claim 1, wherein the third lens has a meniscus shape with a convex surface facing the image side in the vicinity of the optical axis. The imaging lens according to claim 1, wherein the following conditional expression is satisfied.
0.05 <THIL3 / Σd <0.2 (3)
However,
THIL3: Thickness on the optical axis of the third lens (mm)
Σd: distance on the optical axis from the object side surface of the first lens to the image side surface of the fifth lens (mm) The imaging lens according to claim 1, wherein the following conditional expression is satisfied.
0.2 <R1 / f <0.5 (4)
However,
R1: radius of curvature of object side surface of the first lens (mm)
f: Focal length of the entire imaging lens system (mm) The imaging lens according to claim 1, wherein the following conditional expression is satisfied.
0.02 <THIL2 / Σd <0.12 (5)
However,
THIL2: thickness on the optical axis of the second lens (mm)
Σd: distance on the optical axis from the object side surface of the first lens to the image side surface of the fifth lens (mm) The imaging lens according to claim 1, wherein the following conditional expression is satisfied.
20 <ν5-ν4 <50 (6)
However,
ν5: Abbe number of the fifth lens ν4: Abbe number of the fourth lens The imaging lens according to claim 1, wherein the following conditional expression is satisfied.
0.2 <f / (2 × f1 × Fno) <0.4 (7)
However,
f: Focal length of the entire imaging lens system (mm)
f1: Focal length (mm) of the first lens
Fno: F-number of the entire imaging lens system The imaging lens according to claim 1, wherein the following conditional expression is satisfied.
Σd / 2Y <0.6 (8)
However,
Σd: distance on the optical axis from the object side surface of the first lens to the image side surface of the fifth lens (mm)
2Y: Diagonal length of the imaging surface of the solid-state imaging device (mm)   The imaging lens according to claim 1, further comprising a lens having substantially no power.   An imaging apparatus comprising the imaging lens according to claim 1 and an imaging element.   A portable terminal comprising the imaging device according to claim 10.

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