Imaging lens, imaging device, and information processing device

Abstract

Provided is an imaging lens, an imaging device, and an information processing device that have a wide angle of view, are bright, have high performance, and can be made compact. The imaging lens 100 is composed of a first lens L1 to a fifth lens L5 arranged in order from the object side, and an aperture stop S between the first lens L1 and the second lens L2. The first lens L1 is a negative meniscus lens with a concave surface facing the object side or the image side, the second lens L2 is a biconvex positive lens, the third lens L3 is a negative lens with a concave surface facing the object side, the fourth lens L4 is a positive meniscus lens with a convex surface facing the image side, and the fifth lens L5 is a negative meniscus lens with a convex surface facing the object side and a concave surface facing the image side.

Description

[Technical Field]

[0001] The present disclosure relates to an imaging lens, an imaging device, and an information processing device. [Background technology]

[0002] BACKGROUND ART In recent years, imaging devices such as digital still cameras, digital camcorders, and smartphone cameras that include solid-state imaging elements such as CCDs (Charge Coupled Devices) and CMOSs ​​(Complementary Metal Oxide Semiconductors) and imaging lenses have become widespread.

[0003] The solid-state imaging elements used in these imaging devices are becoming increasingly more pixelated, and as the number of pixels of these solid-state imaging elements increases, imaging lenses are also being required to have higher optical performance.

[0004] In recent years, PCs (Personal Computers) such as laptops and tablet terminal devices equipped with imaging devices have been used to distribute videos and communicate over the Web. For this reason, imaging devices, particularly those mounted on the bezel of laptops and under-display cameras (UDCs) concealed directly below the displays of tablet terminal devices, have been made smaller in size to facilitate portability.

[0005] Furthermore, the market is primarily looking for imaging devices that combine high performance with compactness, and imaging lenses are also being required to not only be high performance but also be compact. For this reason, imaging lenses that combine high performance with compactness are known (see, for example, Patent Documents 1 to 4). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2017-513034 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-106155 [Patent Document 3] U.S. Patent No. 11,500,182 [Patent Document 4] U.S. Patent No. 10,429,620 Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, when video distribution and communication over the Web are performed using imaging devices mounted on laptops, tablet terminal devices, etc., there has been a demand for imaging lenses that are smaller, have a wider angle of view, are brighter, and have higher performance than conventional imaging lenses, in order to provide mobility.

[0008] However, in the imaging lenses described in Patent Documents 1 to 4 above, no consideration is given to placement in the bezel of a laptop or the space directly below the display of a tablet terminal device, and in order to achieve a wide angle of view, the overall length in the optical axis direction becomes long, which increases the thickness of the bezel and the display, making it difficult to reduce the size.

[0009] The present disclosure has been made in view of the above, and has an object to provide a small, wide-angle, bright, and high-performance imaging lens, an imaging device, and an information processing device. [Means for solving the problem]

[0010] In order to solve the above-mentioned problems and achieve the object, an imaging lens according to a first aspect of the present disclosure includes a first lens to a fifth lens arranged in order from the object side, and an aperture stop between the first lens and the second lens, wherein the first lens is a negative meniscus lens with a concave surface facing the object side or a concave surface facing the image side, the second lens is a biconvex positive lens, the third lens is a negative lens with a concave surface facing the object side, the fourth lens is a positive meniscus lens with a convex surface facing the image side, and the fifth lens is a negative meniscus lens with a convex surface facing the object side and a concave surface facing the image side, and wherein, when a focal length of the entire optical system is f and a total lens length is TTL, the imaging lens satisfies condition (1): 0.50 < f / TTL < 0.60 (1) Satisfy.

[0011] An imaging device according to a second aspect of the present disclosure includes the imaging lens described above, and a solid-state imaging element that receives an image formed by the imaging lens and generates an imaging signal.

[0012] An information processing device according to a third aspect of the present disclosure includes the imaging device described above, and a display unit that displays an image corresponding to the imaging signal generated by the imaging device. [Effects of the Invention]

[0013] The present disclosure provides an advantageous effect of providing a compact, wide-angle, bright, and high-performance imaging lens. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing a lens configuration of an imaging lens according to a first embodiment of the present disclosure. [Figure 2A] FIG. 2A is an aberration diagram of the imaging lens according to the first embodiment of the present disclosure. [Figure 2B] FIG. 2B shows a distortion grating of the imaging lens according to the first embodiment of the present disclosure. [Figure 2C] FIG. 2C shows the MTF of the imaging lens according to the first embodiment of the present disclosure. [Figure 3] FIG. 3 is a diagram showing a lens configuration of an imaging lens according to a second embodiment of the present disclosure. [Figure 4A] FIG. 4A is an aberration diagram of the imaging lens according to the second embodiment of the present disclosure. [Figure 4B] FIG. 4B shows a distortion grating of the imaging lens according to the second embodiment of the present disclosure. [Figure 4C] FIG. 4C shows the MTF of the imaging lens according to the second embodiment of the present disclosure. [Figure 5] FIG. 5 is a diagram illustrating a lens configuration of an imaging lens according to the third embodiment of the present disclosure. [Figure 6A] FIG. 6A is an aberration diagram of the imaging lens according to the third embodiment of the present disclosure. [Figure 6B] FIG. 6B shows a distortion grating of an imaging lens according to the third embodiment of the present disclosure. [Figure 6C] FIG. 6C shows the MTF of the imaging lens according to the third embodiment of the present disclosure. [Figure 7] FIG. 7 is a diagram showing a lens configuration of an imaging lens according to the fourth embodiment of the present disclosure. [Figure 8A] FIG. 8A is an aberration diagram of the imaging lens according to the fourth embodiment of the present disclosure. [Figure 8B] FIG. 8B shows a distortion grating of the imaging lens according to the fourth embodiment of the present disclosure. [Figure 8C] FIG. 8C shows the MTF of the imaging lens according to the fourth embodiment of the present disclosure. [Figure 9] FIG. 9 is a diagram showing a lens configuration of an imaging lens according to a fifth embodiment of the present disclosure. [Figure 10A] FIG. 10A is an aberration diagram of the imaging lens according to the fifth embodiment of the present disclosure. [Figure 10B] FIG. 10B shows a distortion grating of the imaging lens according to the fifth embodiment of the present disclosure. [Figure 10C] FIG. 10C shows the MTF of the imaging lens according to the fifth embodiment of the present disclosure. [Figure 11]FIG. 11 is a diagram illustrating a lens configuration of an imaging lens according to the sixth embodiment of the present disclosure. [Figure 12A] FIG. 12A is an aberration diagram of the imaging lens according to the sixth embodiment of the present disclosure. [Figure 12B] FIG. 12B shows a distortion grating of an imaging lens according to the sixth embodiment of the present disclosure. [Figure 12C] FIG. 12C shows the MTF of the imaging lens according to the sixth embodiment of the present disclosure. [Figure 13] FIG. 13 is a diagram showing a schematic configuration of an information processing device including an imaging device having an imaging lens according to each embodiment of the present disclosure. [Figure 14] FIG. 14 is a diagram showing a schematic configuration of the imaging device of FIG. [Figure 15] FIG. 15 is a block diagram showing a functional configuration of an information processing device including an imaging device having an imaging lens according to each embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0015] An imaging lens, an imaging device, and an information processing device according to the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to the following embodiments. Furthermore, the drawings referred to in the following description merely show a rough outline of the shape, size, and positional relationship to the extent that the contents of the present disclosure can be understood. In other words, the present disclosure is not limited to only the shape, size, and positional relationship exemplified in each drawing. Furthermore, the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0016] [Embodiment Mode] 1, 3, 5, 7, 9, and 11 are cross-sectional views showing the lens configurations of the imaging lenses of Embodiments 1 to 6. In each cross-sectional view, the left side is the object side (front) and the right side is the image side (rear).

[0017] The imaging lens 100 of each embodiment is composed of a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5, which are arranged in that order from the object side to the image side, and an aperture stop S (STOP) which is arranged between the first lens L1 and the second lens L2.

[0018] In Figures 1, 3, 5, 7, 9, and 11, the reference numerals 1 to 11 attached to the first lens L1 through the fifth lens L5 and the aperture diaphragm S represent the surfaces of the respective lenses or diaphragms. Hereinafter, these surfaces will be referred to as surfaces 1 to 11 in order from the object side to the image side. Surface 3 is the surface of the aperture diaphragm S. Furthermore, in Figures 1, 3, 5, 7, 9, and 11, the reference numeral CG represents a transparent plane-parallel plate equivalent to a cover glass of a solid-state imaging element and at least one of various filters. The incident side of the transparent plane-parallel plate CG is referred to as surface 12, and the image side is referred to as surface 13.

[0019] Imaging lens 100 is composed of, in order from the object side, an aperture stop S, a first lens L1 to a fifth lens L5, and the aperture stop S is arranged between L1 and L2. In imaging lens 100, the first lens L1 is a negative lens, and the second lens is a lens with positive power. In imaging lens 100, the third lens is a negative lens, the fourth lens is positive, and the fifth lens is a negative lens. In imaging lens 100, the lens closest to the object side is a positive lens, and the lens closest to the image plane is a negative lens. With this lens configuration, the incident angle of light rays tends to be low, and the exit angle of light rays becomes large at the negative lens of the final lens, the fifth lens L5, but by optimizing the power balance of the lenses, good telecentricity on the image side can be achieved.

[0020] The first lens L1 is a negative meniscus lens with a concave surface facing either the object side or the image plane side, and may be aspherical. The lens may also have an inflection point in its peripheral region. Here, the inflection point in the peripheral region refers to a region that includes 60 to 80 percent of the aperture of the first lens L1 on the surface 2 side, extending from the optical axis toward the outer edge.

[0021] The second lens L2 is constructed using a positive lens.

[0022] The third lens L3 is a negative lens whose concave surface faces the object side and whose surface has an inflection point at the periphery.

[0023] The fourth lens L4 is composed of a positive meniscus lens with a convex surface on the image side.

[0024] The fifth lens L5 is a negative meniscus lens with a convex surface on the object side and a concave surface on the image side.

[0025] The first lens L1 to the fifth lens L5 configured in this manner are all aspherical lenses, each characterized by its aspherical shape. Furthermore, by making the first lens L1 and the fifth lens L5 have shapes with inflection points, it is possible to highly correct aberrations while keeping the thickness (total length) of the imaging lens 100 in the light direction thin.

[0026] As for the lens material, optical plastic materials can be used, as will be shown in the examples below.

[0027] 2A to 2C, 4A to 4C, 6A to 6C, 8A to 8C, 10A to 10C, and 12A to 12C respectively show longitudinal aberration diagrams, MTF diagrams, and distortion grating diagrams for imaging lens 100 according to the first to sixth embodiments. The spherical aberration diagrams show the amount of spherical aberration for the d-line (yellow: wavelength 587.6 nm), g-line (blue: wavelength 435.8 nm), and C-line (red: 653.3 nm). The astigmatism diagrams show the amount of astigmatism at the sagittal image plane, with the solid line S indicating the amount of astigmatism at the sagittal image plane, and the dashed line T indicating the amount of astigmatism at the tangential image plane. The distortion diagrams show the amount of distortion only for the d-line. Angle (deg) indicates the half imaging angle of view (°). Regarding the distortion grating, the thin line indicates the paraaxial (ideal FOV) grating, and the thick line indicates the actual (actual FOV) grating. For MTF, the frequencies are 1 / 8Ny, 1 / 4Ny, and 1 / 2Ny. At 1 / 8Ny, the five-dotted line indicates the MTF of the sagittal image plane, and the coarse-dashed line indicates the MTF of the tangential image plane. At 1 / 4Ny, the three-dotted line indicates the MTF of the sagittal image plane, and the fine-dashed line indicates the MTF of the tangential image plane. At 1 / 2Ny, the two-dotted line indicates the MTF of the sagittal image plane, and the fine-dashed line indicates the MTF of the tangential image plane.

[0028] Next, the conditions for the imaging lens 100 of each embodiment will be described. The imaging lens 100 of each embodiment satisfies the following condition (1), where f is the focal length of the entire optical system and TTL is the total lens length. 0.50 < f / TTL < 0.60 (1)

[0029] Condition (1) is a conditional expression relating to the overall focal length and overall lens length of the imaging lens 100.

[0030] When f / TTL is equal to or less than the lower limit of condition (1), the overall focal length tends to be shorter, which is advantageous for achieving a wider angle of view. However, astigmatism tends to be excessive and distortion tends to be large, making it difficult to achieve the desired performance. On the other hand, when f / TTL is equal to or greater than the upper limit of condition (1), spherical aberration and astigmatism tend to be improved, but the angle of view tends to be narrower and the overall length tends to be longer. This is undesirable because it makes it difficult to achieve the desired performance of the embodiment of the present disclosure. Therefore, by satisfying condition (1), the imaging lens 100 can achieve a balance between a short shape (low profile) and high performance. In other words, if condition (1) is not satisfied, when the imaging lens 100 is placed in the bezel of a display panel of a laptop or the like, it cannot be accommodated within the space in the thick portion of the bezel or within the space accommodating the display panel. This causes the imaging lens 100 to protrude from the surface of the bezel, or the thickness of the bezel or the display panel to increase. As a result, if the condition (1) is not satisfied, when the imaging lens 100 is placed in a bezel or a display panel, the thickness of the display panel or bezel increases, which impairs portability and aesthetic appeal.

[0031] The imaging lens 100 of each embodiment satisfies the following condition (2), where the total lens length is TTL and the air gap between the first lens and the second lens is D1-2. 3.0e-3 < D1-2 / TTL < 3.0e-2 (2)

[0032] Condition (2) is a condition for the overall length and the distance between the D1-2 lenses, and is a condition for maintaining a balance between the overall length and aberration.

[0033] If D1-2 / TTL is equal to or less than the lower limit of condition (2), the overall length will increase and distortion will be improved, but the overall length will tend to increase, which is undesirable. If condition (2) is equal to or greater than the upper limit, the overall length will be reduced, but the balance between various aberrations will be lost, making it difficult to achieve the desired performance.

[0034] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (3), where the focal length of the first lens is f1 and the focal length of the entire optical system is f. 4.5 < |f1 / f| < 7.5 (3)

[0035] Condition (3) defines the relationship between the focal length f1 of the first lens and the focal length f of the entire optical system.

[0036] The first lens L1 is a negative lens, and in the optical system of the present disclosure, it is a wide-angle lens with negative power that is located closer to the object side than the aperture stop. Therefore, the power arrangement of the first lens L1 is a necessary condition for achieving both aberration and angle of view. In order to achieve an appropriate balance between the angle of view and various aberrations and compactness, it is preferable for the condition to be within the range of conditions.

[0037] If the value is equal to or less than the lower limit of condition (3), the focal length of the entire system will be long, but the focal length f1 of the first lens L1 will be short, which undesirably shifts astigmatism to the positive side. Conversely, if the value is equal to or greater than the upper limit of condition (3), the focal length of f1 will be long, which shifts astigmatism to the negative side, disrupting the aberration balance and increasing the external size of the lens, which are undesirable.

[0038] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (4) when the focal length of the first lens is f1 and the focal length of the second lens is f2. 4.5 < |f1 / f2| < 6.0 (4)

[0039] Condition (4) defines the relationship between the focal length f1 of the first lens and the focal length f2 of the second lens.

[0040] If condition (4) is below its lower limit, the astigmatism tends to be large on the positive side, and the astigmatic difference tends to be large, which is undesirable, while if condition (4) is above its upper limit, the astigmatism tends to be large on the negative side, and the astigmatic difference tends to be large, and the spherical aberration tends to be large on the positive side, which is undesirable, as the curvature of field increases. By satisfying condition (4), imaging lens 100 can achieve high performance.

[0041] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (4) when the focal length of the first lens is f1 and the focal length of the fifth lens is f5. 6.0 < f1 / f5 < 10.5 (5)

[0042] The condition (5) sets forth the relationship between the focal length f1 of the first lens and the focal length f5 of the fifth lens.

[0043] If condition (5) is below its lower limit, distortion will tend to increase on the positive side, which is undesirable, and if condition (5) is above its upper limit, distortion and astigmatism will tend to increase on the negative side, which is undesirable. By satisfying condition (5), imaging lens 100 can achieve high performance.

[0044] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (6) when the focal length of the fourth lens is f4 and the focal length of the fifth lens is f5. 0.75 < |f4 / f5| < 0.95 (6)

[0045] The condition (6) sets forth the relationship between the focal length f4 of the fourth lens and the focal length f5 of the fifth lens.

[0046] If condition (6) is not greater than the lower limit, the astigmatism tends to be positive and the curvature of field tends to be large, whereas if condition (6) is not less than the upper limit, the astigmatism tends to be negative and the distortion aberration tends to be undercorrected negatively, which is undesirable. By satisfying condition (6), imaging lens 100 can achieve high performance.

[0047] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (7) when the focal length of the lens group closer to the object side than the aperture stop is F1 and the focal length of the lens group closer to the image plane side than the aperture stop is F2. 5.0 < |F1 / F2| < 7.7 (7)

[0048] Condition (7) is a condition for the balance between the focal length F1 of the lens group on the object side of the aperture stop and the focal length F2 of the lens group on the image plane side of the aperture stop.

[0049] If condition (7) is not greater than the lower limit, the spherical aberration and astigmatism will be biased to the positive side and the distortion will be negative, which is undesirable, whereas if condition (7) is not less than the upper limit, the astigmatism will be negative and will be undercorrected, which is undesirable. By satisfying condition (7), imaging lens 100 can achieve high performance.

[0050] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (8) when the exit pupil position is EXP and the image height is IH. 0.85 < |EXP / IH| < 1.15 (8)

[0051] Condition (8) is a condition for optimizing the angle of incidence of light rays onto the image plane.

[0052] If EXP / IH is equal to or less than the lower limit of condition (8), the light incident angle tends to be high. This makes it difficult for light rays to enter the sensor, which is undesirable. On the other hand, if EXP / IH is equal to or greater than the upper limit of condition (8), the light incident angle tends to be low, but it tends to be difficult to reduce the overall length of the optical system and thereby achieve compactness. For this reason, imaging lens 100 can achieve compactness by satisfying condition (8).

[0053] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (9) when the total optical length is TTL and the effective optical diameter of the lens closest to the object side is EfD1. 2.0 < TTL / EfD1 < 3.0 (9)

[0054] Condition (9) is a condition for optimizing the overall optical length and the size of the lens closest to the object.

[0055] If condition (9) is below its lower limit, the total length tends to become even shorter, or EfD1 tends to become larger, which is undesirable as it tends to worsen various aberrations. If condition (9) is above its upper limit, the total length tends to become longer, which improves optical performance but also hinders compactness, which is undesirable. Therefore, by satisfying condition (9), both high performance and compactness can be achieved.

[0056] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (10) when the total optical length is TTL and the image height of the optical system is IH. 0.6 < TTL / {(IH+0.1)*2} < 0.7 ···(10)

[0057] Condition (10) is a condition for optimizing the total optical length and the image height.

[0058] If condition (10) is below its lower limit, the total length tends to become even shorter or the Ef image height tends to become larger, which is undesirable because it worsens various aberrations. Furthermore, if condition (10) is above its upper limit, the total length tends to become longer, which improves optical performance but makes it difficult to achieve compactness, which is undesirable. Therefore, satisfying condition (10) allows for both high performance and compactness. Furthermore, the maximum effective image circle (hereinafter referred to as MIC) of the optical system is required to ensure the image formed through the imaging lens 100 even if the image sensor and the imaging lens 100 are misaligned by 0.1 mm in the shift direction during manufacturing of the imaging lens 100. In other words, satisfying condition (10) allows the imaging lens 100 to achieve both high performance and compactness.

[0059] Furthermore, the imaging lens 100 of each embodiment satisfies condition (11) when the refractive index of the material of the first lens L1 to the d-line is N1 and the refractive index of the material of the fifth lens L5 to the d-line is N5. N1 <N5 ···(11)

[0060] Condition (11) defines the relationship between the refractive index N1 of the material of the first lens L1 and the refractive index N5 of the material of the fifth lens L5. The first lens L1 is a negative lens, and must have a large negative refractive power to fully exhibit the retrofocus function. In the present disclosure, the refractive index N1 of the first lens L1 is formed from a material with a refractive index smaller than the refractive index N5 of the fifth lens L5, and by satisfying condition (11), the desired retrofocus function and good chromatic aberration can be achieved.

[0061] In the imaging lens 100 of each embodiment, the refractive index N1 of the material of the first lens L1 with respect to the d-line satisfies the condition (12). 1.49 <N1<1.55 ···(12)

[0062] If the refractive index N1 is equal to or less than the lower limit of condition (12), the optical performance will be further improved, but costs will increase, which is not preferable. On the other hand, if the refractive index N1 is equal to or greater than the upper limit of condition (12), chromatic aberration will be adversely affected, which is not preferable. Therefore, by making the imaging lens 100 satisfy condition (12), a balance between cost and chromatic aberration can be achieved, and an imaging lens 100 that is bright, high-performance, and small (compact) can be realized.

[0063] In the imaging lens 100 of each embodiment, the refractive index N5 of the material of the fifth lens L5 with respect to the d-line satisfies the condition (13). 1.63 <N5<1.67 ···(13)

[0064] If the refractive index N5 is equal to or smaller than the lower limit of the condition (13), or if the refractive index N5 is equal to or larger than the upper limit of the condition (13), the balance of chromatic aberration is lost. In consideration of the balance between cost and chromatic aberration, satisfying the condition (13) makes it possible to realize a bright, high-performance, and compact imaging lens 100.

[0065] Furthermore, the imaging lens 100 of each embodiment satisfies the condition (14) when the total optical length is TTL. TTL < 3.0mm (14)

[0066] If condition (14) is not satisfied, it will be difficult to incorporate the imaging lens into the bezel of a monitor such as a laptop (notebook PC), and therefore it is preferable to satisfy condition (14). That is, if condition (14) is not satisfied, when the imaging lens 100 is placed in the bezel of a display panel of a laptop or the like, it will not be able to be accommodated within the space of the thick part of the bezel or within the space accommodating the display panel, and the imaging lens 100 will protrude from the surface of the bezel, or the thickness of the bezel or the display panel will increase. As a result, if condition (14) is not satisfied and the imaging lens 100 is placed in the bezel or the display panel, the thickness of the display panel or bezel will increase, which will impair portability and aesthetics.

[0067] [Imaging device] Next, an embodiment of an information processing device (PC) equipped with an imaging device using the imaging lens 100 of each embodiment as an imaging optical system will be described.

[0068] Fig. 13 is a diagram showing a schematic configuration of an information processing device equipped with an imaging device having the imaging lens 100 of each embodiment. Fig. 14 is a diagram showing a schematic configuration of the imaging device of Fig. 13. Fig. 15 is a block diagram showing a functional configuration of an information processing device equipped with an imaging device having the imaging lens of each embodiment.

[0069] The information processing device 30 shown in FIGS. 13 to 15 includes at least an imaging device 31, a signal processing unit 32, an image processing unit 33, a control unit 34, a display unit 35, a storage unit 36, a communication unit 37, an input unit 38, and an audio input / output unit 39.

[0070] Under the control of the control unit 34, the imaging device 31 generates an imaging signal by capturing an image of a predetermined field of view, and outputs the imaging signal to the signal processing unit 32. As shown in FIG. 14 , the imaging device 31 includes at least a cover 311, the imaging lens 100 of each embodiment, and a solid-state imaging element 312. The imaging device 31 is disposed on the front side of the information processing device 30. Specifically, the imaging device 31 is disposed in a position where it can capture an image of the user of the information processing device 30. Of course, the position of the imaging device 31 can be changed as appropriate depending on the shape, size, and usage mode of the information processing device 30.

[0071] The cover 311 is configured using a cover glass or the like, which is a member for preventing dirt and dust from being generated on the imaging lens 100. Note that the information processing device 30 may further provide a lid or the like on the cover 311 that opens and closes in response to a user operation.

[0072] The solid-state imaging element 312 receives the image of the object to be imaged formed by the imaging lens 100 and generates an imaging signal by photoelectric conversion. The solid-state imaging element 312 is configured using a CCD sensor, a CMOS sensor, or the like. The solid-state imaging element 312 preferably has 8 million or more effective pixels, so-called 4K or more (3840 x 2160 or more), arranged in a two-dimensional matrix.

[0073] Under the control of the control unit 34, the signal processing unit 32 performs A / D conversion processing and the like on the imaging signal input from the solid-state imaging element 312 to convert it into a digital imaging signal and outputs it to the image processing unit 33. The signal processing unit 32 is configured using, for example, a DSP (Digital Signal Processor) or the like.

[0074] Under the control of the control unit 34, the image processing unit 33 performs predetermined image processing on the digital imaging signal input from the signal processing unit 32 and outputs the result to the display unit 35 or the storage unit 36. The image processing unit 33 is configured using, for example, a GPU (Graphics Processing Unit) or the like. Here, the predetermined image processing includes electrical shading correction processing, white balance adjustment processing, image center cropping processing, noise reduction processing, and the like.

[0075] The control unit 34 controls each unit constituting the information processing device 30. The control unit 34 includes a processor and a memory. The processor is configured using a CPU, an FPGA (Field-Programmable Gate Array), etc. The memory is configured using a RAM (Random Access Memory), a ROM (Read Only Memory), etc.

[0076] Under the control of the control unit 34, the display unit 35 displays moving images being captured that have been image processed by the image processing unit 33, captured captured images, still images corresponding to image signals stored in the storage unit 36, and various information related to the information processing device 30. The display unit 35 also has a display panel 351 that displays images and a bezel unit 352 provided around the periphery of the display panel. The imaging device 31 is disposed in the bezel unit 352. Specifically, when the information processing device 30 is in use, the imaging device 31 is disposed on the bezel unit 352 facing the user, with the object side facing the bezel unit 352. The thickness of the bezel unit 352 is approximately 5.0 mm, and an imaging lens is required to have a thickness that takes this into consideration, and the imaging lens of the present invention can be used for this thickness.

[0077] The storage unit 36 ​​stores various information related to the information processing device 30, programs executed by the information processing device 30, and imaging signals (RAW data and JPEG data) captured by the imaging device 31. The storage unit 36 ​​is configured using a flash memory, an SSD (Solid State Drive), an HDD (Hard Disk Drive), a memory card, etc.

[0078] The communication unit 37 transmits an imaging signal captured by the imaging device 31 to the outside via a network in accordance with a predetermined communication standard, and receives various information input from the outside, under the control of the control unit 34. The communication unit 37 uses a communication standard that complies with communication standards such as 3GPP (registered trademark), 4G established by IEEE, LTE, 5G, WiMAX, and Wi-Fi (registered trademark).

[0079] The input unit 38 receives an operation input from the user and outputs operation information corresponding to the received operation to the control unit 34. The input unit 38 is configured using, for example, a touch panel, a keyboard, a mouse, and the like.

[0080] Under the control of the control unit 34, the audio input / output unit 39 receives input of external sound, converts it into an audio signal, and outputs it to the storage unit 36 ​​or the communication unit 37. Also, under the control of the control unit 34, the audio input / output unit 39 converts an audio signal input from the storage unit 36 ​​or the communication unit 37 and outputs it to the outside. The audio input / output unit 39 is configured using a microphone, a speaker, etc.

[0081] The information processing device 30 configured in this manner can use the imaging device 31 having the imaging lens 100 to communicate with an external device in high-quality 4K images via web communication via a network.

[0082] In the embodiment, a PC has been described as an example of the information processing device 30, but the imaging device 31 can be applied to imaging devices such as tablet terminals, mobile phones, etc. Of course, the imaging device 31 can also be applied to a web camera or the like that can communicate with a PC or the like via wired or wireless communication.

[0083] According to the embodiment described above, it is possible to realize a compact, wide-angle, bright, and high-performance camera.

[0084] Furthermore, according to the embodiment, a half angle of view of approximately 55° or more can be achieved with five lenses.

[0085] Furthermore, according to the embodiment, imaging lens 100 can be realized that has a wide angle of view, a small F-number, high performance, and a small size, and therefore, in the case of video shooting, it can accommodate shooting in various environments such as dark environments and high-speed shooting.

[0086] Furthermore, according to the embodiment, it is possible to realize a wide-angle, bright, high-performance, and compact device, thereby improving the matching between the incident angle at the light receiving element of the solid-state imaging element on the image side and the light rays incident on the light receiving surface.

[0087] Furthermore, according to the embodiment, a small, bright, high-performance lens with a half angle of view of approximately 55° can be constructed from five lenses, and therefore it can be used as a fixed focal length lens for use in mobile phones such as smartphones and PCs, for example. Therefore, when high-pixel video recording of 4K or more (3840 x 2160 or more) is required, sufficient aberration correction can be performed compared to conventional imaging lenses, and the required performance can be met.

[0088] Furthermore, according to the embodiment, a small, bright, high-performance lens with a half angle of view of approximately 55° can be configured using five lenses, which shortens the overall length of imaging lens 100 in the optical axis direction and reduces the lens diameter, thereby achieving a compact size. This reduces the refractive power of the compact lens and reduces the effects of manufacturing errors and assembly errors. As a result, productivity is improved and production costs can be reduced.

[0089] Furthermore, according to the embodiment, when the imaging device 31 is disposed in the bezel portion 352 of the display panel 351 of a laptop or the like, it can be accommodated within the space defined by the thickness of the bezel portion 352, thereby realizing a wide-angle, bright, high-performance, and compact device. Note that, although the imaging device 31 is provided in the bezel portion 352 in the embodiment, even if it is provided in the internal space of the display panel 351 as in an under-display camera, the imaging lens 100 may protrude from the surface of the bezel portion 352, or the thickness of the bezel portion 352 or the display panel 351 may become large.

[0090] Various inventions can be formed by appropriately combining multiple components disclosed in the information processing device according to the embodiment of the present disclosure. For example, some components may be deleted from all of the components described in the information processing device according to the embodiment of the present disclosure. Furthermore, the components described in the information processing device according to the embodiment of the present disclosure may be appropriately combined.

[0091] Furthermore, in the information processing device according to the embodiment of the present disclosure, the above-described "unit" can be read as "means" or "circuit," etc. For example, a control unit can be read as control means or a control circuit.

[0092] In addition, the program to be executed by the information processing device according to the embodiment of the present disclosure is provided as file data in an installable or executable format recorded on a recording medium that can be read by a computer, such as a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital Versatile Disk), a USB medium, or a flash memory.

[0093] Furthermore, the program executed by the information processing device according to the embodiment of the present disclosure may be configured to be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. [Example]

[0094] Examples 1 to 6 of the imaging lens 100 corresponding to the first to sixth embodiments, respectively, are shown below. The meanings of the symbols in each example are as follows: f: focal length of the entire lens system fn (n=1 to 5): focal length of each lens FNo.: Aperture (F number) R: Radius of curvature of the surface D: Surface spacing Nd: Refractive index for the d line Vd: Abbe number for the d line SD: Effective radius An aspherical surface can be expressed by the well-known formula (20) below using aspherical coefficients, where X is the depth in the optical axis direction, H is the height from the optical axis, R is the paraxial radius of curvature, k is the conic constant, and CN is a high-order aspherical coefficient (N=4 or an even number). X=(H 2 / R) / [1+{1-k(H / r) 2} 1 / 2 ] +Σ N=4:even CNH N ···(20) Here, Σ N≧4:even means the sum for N being an even number greater than or equal to 4.

[0095] [Example 1] f=1.7mm, FNo.=2.2, ω=56° The data for Example 1 are shown in Table 1.

[0096] [Table 1]

[0097] The aspheric data is shown below. [Table 2] In the above notation of aspherical surfaces, for example, "9.1503.E-01" means "9.1503*10-1." This also applies to the other examples below.

[0098] The parameter values ​​for each condition are as follows: Table 3 also lists EP: entrance pupil position. [Table 3]

[0099] In addition to conditional expressions (1) to (9), this table also lists (11) to (14) for reference. [Table 4]

[0100] In each example, the first lens L1 to the fourth lens L4 have aspherical surfaces, and the aspherical surfaces effectively correct aberrations.

[0101] The aberration diagrams, MTF, and distortion grating for Example 1 are shown in FIGS. 2A to 2C, and as is clear from each diagram, the performance is excellent.

[0102] [Example 2] f=1.7mm, FNo.=2.2, ω=56° The data for Example 2 are shown in Table 5.

[0103] [Table 5]

[0104] The aspheric data is shown below. [Table 6]

[0105] The parameter values ​​for each condition are as follows: [Table 7] [Table 8]

[0106] The aberration diagrams, MTF, and distortion gratings are shown in FIGS. 4A to 4C, and as is clear from each diagram, the performance is excellent.

[0107] [Example 3] f=1.5mm, FNo.=2.2, ω=59° The data for Example 3 are shown in Table 9.

[0108] [Table 9]

[0109] The aspheric data is shown below. [Table 10]

[0110] The parameter values ​​for each condition are as follows: [Table 11]

[0111] [Table 12]

[0112] The aberration diagrams, MTF, and distortion gratings are shown in FIGS. 6A to 6C, and as is clear from each diagram, the performance is excellent.

[0113] [Example 4] f=1.6mm, FNo.=2.2, ω=54° The data for Example 4 are shown in Table 13. [Table 13]

[0114] The aspheric data is shown below. [Table 14]

[0115] The parameter values ​​for each condition are as follows: [Table 15]

[0116] [Table 16]

[0117] The aberration diagrams, MTF, and distortion gratings are shown in FIGS. 8A to 8C, and as is clear from each aberration diagram, the performance is excellent.

[0118] [Example 5] f=1.6mm, FNo.=1.8, HFOV=54° The data for Example 4 are shown in Table 17. [Table 17]

[0119] The aspheric data is shown below. [Table 18]

[0120] The parameter values ​​for each condition are as follows: [Table 19]

[0121] [Table 20]

[0122] The aberration diagrams, MTF, and distortion gratings are shown in FIGS. 10A to 10C, and as is clear from each aberration diagram, the performance is excellent.

[0123] [Example 6] f=1.6mm, FNo.=2.0, HFOV=59° The data for Example 6 are shown in Table 21. [Table 21]

[0124] The aspheric data is shown below. [Table 22]

[0125] The parameter values ​​for each condition are as follows: [Table 23]

[0126] [Table 24]

[0127] The aberration diagrams, MTF, and distortion gratings are shown in FIGS. 12A to 12C, and as is clear from each aberration diagram, the performance is excellent.

[0128] As described above, as shown in Examples 1 to 6 and Figures 2A to 2C, 4A to 4C, 6A to 6C, 8A to 8C, 10A to 10C, and 12A to 12C, the imaging lens 100 of the present disclosure is bright, has high performance, and is compact (shortened in the optical axis direction), and achieves a half angle of view ω of approximately 55° with a five-lens configuration, and is clearly suitable as an imaging device, particularly an imaging device for laptop PCs.

[0129] Although some of the embodiments of the present application have been described in detail above with reference to the drawings, these are merely examples, and the present invention can be implemented in other forms that have undergone various modifications and improvements based on the knowledge of those skilled in the art, including the aspects described in the disclosure of the present invention.

[0130] 30 Information processing equipment 31 Imaging device 100 Imaging Lens L1 First lens L2 Second lens L3 Third lens L4 4th lens L5 Fifth lens S aperture stop CG cover glass

Claims

1. a first lens to a fifth lens arranged in order from the object side; an aperture stop between the first lens and the second lens; It consists of The first lens is It is a negative meniscus lens with a concave surface facing the object side, The second lens is It is a biconvex positive lens, The third lens is It is a negative lens with a convex surface facing the object side based on the positive or negative radius of curvature on the optical axis. The fourth lens is It is a positive meniscus lens with a convex surface on the image side, The fifth lens is It is a negative meniscus lens with a convex surface on the object side and a concave surface on the image side. When the focal length of the entire optical system is f, the total lens length is TTL, and the air gap between the first lens and the second lens is D1-2, conditions (1) and (2) are satisfied. 0.50 < f / TTL < 0.60...(1) 3.0e-3 < D1-2 / TTL < 3.0e-2 ... (2) An imaging lens that satisfies the above.

2. The imaging lens according to claim 1 , When the focal length of the first lens is f1, the condition (3) 4.5 < |f1 / f| < 7.5...(3) An imaging lens that satisfies the above.

3. The imaging lens according to claim 1 , When the focal length of the first lens is f1 and the focal length of the second lens is f2, the condition (4) 4.5 < | f1 / f2 | < 6.0 ... (4) An imaging lens that satisfies the above.

4. The imaging lens according to claim 1 , When the focal length of the first lens is f1 and the focal length of the fifth lens is f5, the condition (5) 6.0 < f1 / f5 < 10.5 (5) An imaging lens that satisfies the above.

5. The imaging lens according to claim 1 , When the focal length of the fourth lens is f4 and the focal length of the fifth lens is f5, the condition (6) is satisfied. 0.75 < | f4 / f5 | < 0.95 ... (6) An imaging lens that satisfies the above.

6. The imaging lens according to claim 1 , When the focal length of the lens unit on the object side of the aperture stop is F1 and the focal length of the lens unit on the image side of the aperture stop is F2, the condition (7) is satisfied. 5.0 < |F1 / F2 | < 7.7...(7) An imaging lens that satisfies the above.

7. The imaging lens according to claim 1 , When the exit pupil position of the optical system is EXP and the image height of the optical system is IH, the condition (8) is satisfied. 0.85 < | EXP / IH | < 1.15 ... (8) An imaging lens that satisfies the above.

8. The imaging lens according to claim 1 , When the optical effective diameter of the lens closest to the object side is EfD1, the condition (7) is satisfied. 2.0 < TTL / EfD1 < 3.0 (9) An imaging lens that satisfies the above.

9. The imaging lens according to claim 1 , When the image height of the optical system is IH, the condition (10) 0.6 < TTL / {(IH+0.1)*2} < 0.7...(10) An imaging lens that satisfies the above.

10. The imaging lens according to claim 1 ; a solid-state image sensor that receives an image formed by the imaging lens and generates an imaging signal; Equipped with Imaging device.

11. The imaging device according to claim 10; a display unit that displays an image corresponding to the imaging signal generated by the imaging device; Equipped with Information processing device.

12. The information processing device according to claim 11, The display unit a display panel for displaying an image; a bezel portion provided around the display panel; Equipped with The imaging device is disposed on the bezel portion, Information processing device.

13. A first lens to a fifth lens arranged in order from the object side, an aperture stop between the first lens and the second lens; It consists of The first lens is It is a negative meniscus lens with a concave surface facing the object side, The second lens is It is a biconvex positive lens, The third lens is It is a negative lens with a convex surface facing the object side based on the positive or negative radius of curvature on the optical axis. The fourth lens is It is a positive meniscus lens with a convex surface on the image side, The fifth lens is It is a negative meniscus lens with a convex surface on the object side and a concave surface on the image side. When the focal length of the entire optical system is f and the total lens length is TTL, the condition (1) 0.50 < f / TTL < 0.60...(1) Satisfied, When the focal length of the first lens is f1 and the focal length of the second lens is f2, condition (2) 4.5 < | f1 / f2 | < 6.0 ... (2) An imaging lens that satisfies the above.

Images