Imaging lens, imaging device, and information processing device

Abstract

Provided are an imaging lens, an imaging device, and an information processing device which are capable of having a wide angle of view, and which are bright, high-performance, and compact. An imaging lens (100) is provided with, in order from the object side, first to fourth lenses (L1 to L4) and an aperture stop (S) closest to the object side. The first lens (L1) is a positive meniscus lens having a convex surface facing the object side, the second lens (L2) is a lens having an inflection point on at least one surface and having a small deviation ratio, the third lens (L3) is a positive lens having a convex surface facing the image surface side and having an inflection point at the periphery of the lens, and the fourth lens (L4) is a negative lens having a concave surface on the image surface side and having an inflection point at the periphery.

Description

Technical Field

[0001] The present disclosure relates to a photographing lens, a photographing apparatus, and an information processing apparatus. Background Art

[0002] In recent years, photographing apparatuses such as digital cameras, digital video cameras, and cameras for smartphones, which include a single photographing element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) and a photographing lens, have been widespread.

[0003] The high pixel count of the single photographing elements used in these photographing apparatuses has been continuously developed. With the high pixel count of the single photographing element, higher optical performance is also required for the photographing lens.

[0004] In addition, in recent years, in a PC (Personal Computer) equipped with a photographing apparatus, videos are distributed and communicated via the Web. Therefore, in the photographing apparatus, miniaturization considering portability has also been achieved. The photographing apparatuses required in the market are mainly apparatuses that have both high performance and miniaturization, and for the photographing lens, not only high performance but also miniaturization is required. Therefore, there is known a photographing lens that has achieved both high performance and miniaturization (for example, refer to Patent Document 1 and Patent Document 2).

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-513034

[0006] Patent Document 2: Japanese Patent Application Laid-Open No. 2015-106155

[0007] In addition, in recent years, when distributing and communicating videos via the Web, it is desired to be able to photograph with a wider field of view angle than conventional photographing lenses. Therefore, a photographing lens with a wider field of view angle, brighter, higher performance, and smaller size than conventional photographing lenses is desired. Summary of the Invention

[0008] The present disclosure has been made in view of the above, and an object thereof is to provide a photographing lens, a photographing apparatus, and an information processing apparatus that have a wide field of view angle, are bright, have high performance, and are small.

[0009] In order to solve the above problems and achieve the object, the imaging lens of the first aspect of the present disclosure includes: a first lens to a fourth lens, arranged in order from the object side; and an aperture stop, which is closest to the object side. The first lens is a positive meniscus lens with a convex surface facing the object side, the second lens is a lens having an inflection point on at least one surface and a relatively small deviation ratio, the third lens is a positive lens with a convex surface facing the image side and having an inflection point at the peripheral portion of the lens, and the fourth lens is a negative lens with a concave surface on the image side and having an inflection point at the peripheral portion. When the focal length of the first lens is set as f1, the focal length of the fourth lens is set as f4, and the focal length of the entire optical system is set as f, the conditions (1) and (2) are satisfied:

[0010] 0.45 < |f / f1| < 0.80 ··· (1)

[0011] 0.25 < |f4 / f1| < 0.50 ··· (2).

[0012] In addition, the imaging device of the second aspect of the present disclosure includes the above imaging lens and a single imaging element that receives the image formed by the imaging lens and generates an imaging signal.

[0013] In addition, the information processing device of the third aspect of the present disclosure includes the above imaging device and a display unit that displays an image corresponding to the imaging signal generated by the imaging device.

[0014] According to the present disclosure, there is an effect that an imaging lens with a wide field of view angle, bright, high performance, and small size can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a diagram showing the lens configuration of the imaging lens according to Embodiment 1 of the present disclosure.

[0016] Figure 2A It is an aberration diagram of the imaging lens according to Embodiment 1 of the present disclosure.

[0017] Figure 2B It is the MTF of the imaging lens according to Embodiment 1 of the present disclosure.

[0018] Figure 2C It is the distortion grid of the imaging lens according to Embodiment 1 of the present disclosure.

[0019] Figure 3 It is a diagram showing the lens configuration of the imaging lens according to Embodiment 2 of the present disclosure.

[0020] Figure 4A It is an aberration diagram of the imaging lens according to Embodiment 2 of the present disclosure.

[0021] Figure 4B It is the MTF of the imaging lens according to Embodiment 2 of the present disclosure.

[0022] Figure 4C It is the distortion grid of the photographing lens according to Embodiment 2 of the present disclosure.

[0023] Figure 5 It is a diagram showing the lens configuration of the photographing lens according to Embodiment 3 of the present disclosure.

[0024] Figure 6A It is the aberration diagram of the photographing lens according to Embodiment 3 of the present disclosure.

[0025] Figure 6B It is the MTF of the photographing lens according to Embodiment 3 of the present disclosure.

[0026] Figure 6C It is the distortion grid of the photographing lens according to Embodiment 3 of the present disclosure.

[0027] Figure 7 It is a diagram showing the lens configuration of the photographing lens according to Embodiment 4 of the present disclosure.

[0028] Figure 8A It is the aberration diagram of the photographing lens according to Embodiment 4 of the present disclosure.

[0029] Figure 8B It is the MTF of the photographing lens according to Embodiment 4 of the present disclosure.

[0030] Figure 8C It is the distortion grid of the photographing lens according to Embodiment 4 of the present disclosure.

[0031] Figure 9 It is a diagram showing the lens configuration of the photographing lens according to Embodiment 5 of the present disclosure.

[0032] Figure 10A It is the aberration diagram of the photographing lens according to Embodiment 5 of the present disclosure.

[0033] Figure 10B It is the MTF of the photographing lens according to Embodiment 5 of the present disclosure.

[0034] Figure 10C It is the distortion grid of the photographing lens according to Embodiment 5 of the present disclosure.

[0035] Figure 11 It is a diagram showing the lens configuration of the photographing lens according to Embodiment 6 of the present disclosure.

[0036] Figure 12A It is the aberration diagram of the photographing lens according to Embodiment 6 of the present disclosure.

[0037] Figure 12B It is the MTF of the photographing lens according to Embodiment 6 of the present disclosure.

[0038] Figure 12C It is the distortion grid of the photographing lens according to Embodiment 6 of the present disclosure.

[0039] Figure 13 It is a diagram showing the lens configuration of the photographing lens according to Embodiment 7 of the present disclosure.

[0040] Figure 14A It is the aberration diagram of the photographing lens according to Embodiment 7 of the present disclosure.

[0041] Figure 14B It is the MTF of the photographing lens according to Embodiment 7 of the present disclosure.

[0042] Figure 14C It is the distortion grid of the photographing lens according to Embodiment 7 of the present disclosure.

[0043] Figure 15 It is a diagram showing the lens configuration of the photographing lens according to Embodiment 8 of the present disclosure.

[0044] Figure 16A It is the aberration diagram of the photographing lens according to Embodiment 8 of the present disclosure.

[0045] Figure 16B It is the MTF of the photographing lens according to Embodiment 8 of the present disclosure.

[0046] Figure 16C It is the distortion grid of the photographing lens according to Embodiment 8 of the present disclosure.

[0047] Figure 17 It is a diagram showing the lens configuration of the photographing lens according to Embodiment 9 of the present disclosure.

[0048] Figure 18A It is the aberration diagram of the photographing lens according to Embodiment 9 of the present disclosure.

[0049] Figure 18B It is the MTF of the photographing lens according to Embodiment 9 of the present disclosure.

[0050] Figure 18C It is the distortion grid of the photographing lens according to Embodiment 9 of the present disclosure.

[0051] Figure 19 It is a diagram showing the lens configuration of the photographing lens according to Embodiment 10 of the present disclosure.

[0052] Figure 20A It is the aberration diagram of the photographing lens according to Embodiment 10 of the present disclosure.

[0053] Figure 20B It is the MTF of the photographing lens according to Embodiment 10 of the present disclosure.

[0054] Figure 20CIt is the distortion grid of the photographing lens according to Embodiment 10 of the present disclosure.

[0055] Figure 21 It is a diagram showing a schematic configuration of an information processing apparatus of a photographing apparatus including the photographing lens according to each embodiment of the present disclosure.

[0056] Figure 22 It shows Figure 21 a schematic configuration diagram of the photographing apparatus.

[0057] Figure 23 It is a block diagram showing a functional configuration of an information processing apparatus of a photographing apparatus including the photographing lens according to each embodiment of the present disclosure.

[0058] 30... Information processing apparatus, 31... Photographing apparatus, 100... Photographing lens, L1... First lens, L2... Second lens, L3... Third lens, L4... Fourth lens, S... Aperture stop, CG... Glass cover. Detailed embodiments

[0059] Hereinafter, the photographing lens, the photographing apparatus, and the information processing apparatus of the present disclosure will be described with reference to the drawings. In addition, the present disclosure is not limited by the following embodiments. In the following description, the respective drawings referred to schematically show the shape, size, and positional relationship only to the extent that the content of the present disclosure can be understood. That is, the present disclosure is not limited only to the shape, size, and positional relationship illustrated in the respective drawings. In addition, the same reference numerals are added to the same parts and detailed descriptions are omitted.

[0060] [Embodiment]

[0061] Figure 1 , Figure 3 , Figure 5 , Figure 7 , Figure 9 , Figure 11 , Figure 13 , Figure 15 , Figure 17 and Figure 19 are respectively cross-sectional views showing the lens configurations of the photographing lenses according to Embodiments 1 to 10. In each cross-sectional view, the left side is the object side (front), and the right side is the image side (rear).

[0062] The photographing lens 100 of each embodiment includes a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4 arranged in order from the object side to the image side. Further, the photographing lens 100 includes an aperture stop S (STOP) arranged on the object side compared to the first lens L1.

[0063] In addition, in Figure 1 , Figure 3 ,Figure 5 , Figure 7 , Figure 9 , Figure 11 , Figure 13 , Figure 15 , Figure 17 and Figure 19 among the first lens L1 to the fourth lens L4 and the aperture stop S, the attached reference numerals 1 to 9 for any one of them represent the surfaces of each lens or the aperture stop. Hereinafter, these surfaces are sequentially referred to as surface 1 to surface 9 from the object side toward the image side. Surface 1 is the surface of the aperture stop S. And, in Figure 1 , Figure 3 , Figure 5 , Figure 7 , Figure 9 , Figure 11 , Figure 13 , Figure 15 , Figure 17 and Figure 19 among them, the reference numeral CG represents a transparent parallel plate equivalent to a component composed of at least one of the cover glass of the single imaging element and various filter films. The incident side surface of the transparent parallel plate CG is referred to as surface 10, and the image side surface is referred to as surface 11.

[0064] The photographing lens 100 sequentially arranges the aperture stop S, the first lens L1 to the fourth lens L4 from the closest to the object side. For the photographing lens 100, the first lens L1 is a positive lens, and the second lens is a lens with positive or negative power. In addition, for the photographing lens 100, the third lens is composed of a positive lens, and the fourth lens is composed of a negative lens. And, for the photographing lens 100, the lens closest to the object side is a positive lens, and the lens on the image side is a negative lens. In the case of such a lens configuration, the incident angle of light is likely to become low, and the exit angle of light becomes large in the negative lens of the fourth lens L4, the final lens, but by appropriately balancing the power of the lenses, good telecentricity on the image side can be achieved.

[0065] The first lens L1 is a positive meniscus lens with the convex surface facing the object side, and it may also have an inflection point in the peripheral part of the lens on the image side. Here, the inflection point in the peripheral part refers to a region including positions from 60% to 80% of the diameter of the first lens L1 on the side of surface 2 from the optical axis toward the outer edge.

[0066] The second lens L2 is composed of a positive or negative lens having at least one inflection point on one surface and a relatively small deviation ratio, but it may also have inflection points on both surfaces.

[0067] The third lens L3 is composed of a positive lens with the convex surface facing the image side and having an inflection point in the peripheral part of the surface on the object side.

[0068] The fourth lens L4 is composed of a negative lens with the concave surface on the image side and having an inflection point in the peripheral part.

[0069] All of the first lens L1 to the fourth lens L4 configured in this way are aspherical lenses, each having the characteristic of an aspherical shape. Moreover, by making the first lens L1 and the fourth lens L4 have a shape with an inflection point, it is possible to highly correct aberrations in a state where the thickness (total length) in the optical direction of the photographing lens 100 is thin.

[0070] In addition, regarding the material of the lens, as shown in the embodiments described later, an optical plastic material or a glass material can be used.

[0071] Figures 2A - 2C 、 Figures 4A - 4C 、 Figures 6A - 6C 、 Figures 8A - 8C 、 Figures 10A - 10C 、 Figures 12A - 12C 、 Figures 14A - 14C 、 Figures 16A - 16C 、 Figures 18A - 18C and Figures 20A - 20C are the longitudinal aberration diagrams, MTFs, and distortion grids of the photographing lens 100 of Embodiments 1 to 10, respectively. In the spherical aberration diagrams, the spherical aberration amounts for the d-line (yellow: wavelength 587.6 nm), g-line (blue: wavelength 435.8 nm), and C-line (red: 653.3 nm) are shown, respectively. In addition, in the astigmatism diagrams, the solid line S represents the astigmatism amount on the sagittal image plane, and the dashed line T represents the astigmatism amount on the tangential image plane. Moreover, in the distortion aberration diagrams, only the distortion aberration amount for the d-line is shown. In addition, Angle (deg) represents the photographing half field angle (°). In addition, in the MTF, at frequencies of 1 / 4Ny and 1 / 2Ny, the five-dot dashed line represents the MTF of the sagittal image plane at 1 / 4Ny, the thick dashed line represents the MTF of the tangential image plane at 1 / 4Ny, the three-dot dashed line represents the MTF of the sagittal image plane at 1 / 2Ny, and the thin dashed line represents the MTF of the tangential image plane at 1 / 2Ny. In addition, regarding the distortion grid, the thin line represents the paraxial (Paraxial FOV) (ideal) grid, and the thick line represents the real (Actual FOV) (actual) grid.

[0072] Next, the conditions of the photographing lens 100 of each embodiment will be described.

[0073] When the focal length of the first lens L1 is set to f1, the focal length of the fourth lens L4 is set to f4, and the focal length of the entire optical system is set to f, the photographing lens 100 of each embodiment satisfies the following conditions (1) and (2).

[0074] 0.45 < |f / f1| < 0.80 ··· (1)

[0075] 0.25 < |f4 / f1| < 0.50 ··· (2)

[0076] Condition (1) is a conditional expression related to the overall focal length of the photographing lens 100 and the lens power of the first lens L1.

[0077] When f / f1 is below the lower limit of condition (1), there is a tendency for the overall focal length to become shorter, so it is advantageous for wider angle, but since astigmatism tends to become excessive and distortion aberration also tends to increase, it is difficult to achieve the desired performance. In addition, when f / f1 is above the upper limit of condition (1), there is a tendency to improve spherical aberration and astigmatism, but since the field angle tends to become narrow, the desired performance in the embodiments of the present disclosure cannot be achieved, so it is not preferred. Therefore, by satisfying condition (1), the photographing lens 100 can achieve a balance between short form (low profile) and high performance.

[0078] Condition (2) is a conditional expression related to the positive power of the first lens L1 and the negative power of the fourth lens L4.

[0079] When |f4 / f1| is below the lower limit of condition (2), astigmatism tends to be excessive and spherical aberration is also generated relatively largely, so it is difficult to achieve the desired performance. In addition, when |f4 / f1| is above the upper limit of condition (2), spherical aberration tends to be too small, so the balance with astigmatism is broken and it is difficult to achieve the desired performance.

[0080] That is, by satisfying condition (1) and condition (2), the photographing lens 100 can achieve a balance between spherical aberration and astigmatism, and realize a bright, high-performance and small (compact) photographing lens 100. Here, small means reducing the thickness by shortening the overall length in the optical axis direction of the photographing lens 100 and reducing the aperture of the photographing lens 100.

[0081] In addition, when the refractive index of the material of the first lens L1 with respect to the d line is set to N1 and the refractive index of the material of the fourth lens L4 with respect to the d line is set to N4, the photographing lens 100 of each embodiment satisfies condition (3).

[0082] N1 < N4 ··· (3)

[0083] Condition (3) is a condition that defines the relationship between the refractive index N1 of the material of the first lens L1 and the refractive index N4 of the material of the fourth lens L4.

[0084] The first lens L1 is a positive lens. In addition, the fourth lens L4 is a negative lens. In the disclosure, in order to make the chromatic aberration appropriate and balance the miniaturization, it is formed of a material with a refractive index such that the refractive index N1 of the first lens L1 is smaller than the refractive index N4 of the fourth lens L4, and by satisfying condition (3), the desired good chromatic aberration can be achieved.

[0085] In addition, for 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 condition (4).

[0086] 1.49 < N1 < 1.55 ··· (4)

[0087] When the refractive index N1 is below the lower limit of condition (4), the optical performance is further improved, but the cost becomes high, so it is not preferred. In addition, when the refractive index N1 is above the upper limit of condition (4), since the optical performance affects chromatic aberration, it is not preferred. Thus, by making the imaging lens 100 satisfy condition (4), a balance between cost and chromatic aberration is achieved, and a bright, high-performance, and small (compact) imaging lens 100 can be realized.

[0088] In addition, for the imaging lens 100 of each embodiment, the refractive index N4 of the material of the fourth lens L4 with respect to the d-line satisfies condition (5).

[0089] 1.63 < N4 < 1.67 ··· (5)

[0090] When the refractive index N4 is below the lower limit of condition (5), or when the refractive index N4 is above the upper limit of condition (5), the balance of chromatic aberration is broken. Considering the balance between cost and chromatic aberration, by satisfying condition (5), a bright, high-performance, and small imaging lens 100 can be realized.

[0091] In addition, for the imaging lens 100 of each embodiment, when the focal length of the entire optical system (imaging lens 100) is set to f and the overall length of the optical system (the long side direction of the imaging lens 100) is set to OAL, condition (6) is satisfied.

[0092] 0.60 < f / OAL < 0.75 ··· (6)

[0093] Condition (6) is a condition for achieving a balance between the focal length f of the entire optical system and the overall length OAL.

[0094] In the imaging lens 100 of each embodiment, when f / OAL is below the lower limit of condition (6), although further wide-angleization can be achieved, there is a tendency for the front vertex radius to become larger, so there is a concern about an increase in size. In addition, when f / OAL is above the upper limit of condition (6), the overall length of the optical system becomes smaller but it is difficult to achieve wide field angle. The imaging lens 100 that satisfies condition (6) can achieve miniaturization of size and wide-angleization of the field angle.

[0095] In addition, the imaging lens 100 of each embodiment satisfies condition (7) when the overall length of the optical system is set to OAL and the effective optical diameter of the lens (first lens L1) disposed closest to the object side is set to EfD1.

[0096] 2.9 < OAL / EfD1 < 3.6 ··· (7)

[0097] Condition (7) is a condition for achieving the balance between the overall length of the lens and the front spherical diameter of the lens (first lens L1).

[0098] When OAL / EfD1 is below the lower limit of condition (7), miniaturization of the optical system (shortening in the optical axis direction) is achieved, but it is difficult to realize a wide field of view angle. When OAL / EfD1 is above the upper limit of condition (7), the performance of the optical system is improved, but it is difficult to achieve miniaturization (shortening in the optical axis direction). By satisfying condition (7), the imaging lens 100 can achieve miniaturization (shortening in the optical axis direction) and high performance.

[0099] In addition, the imaging lens 100 of each embodiment satisfies condition (8) when the exit pupil position is set to EXP and the image height is set to IH.

[0100] −0.94 < EXP / IH < −0.7 ··· (8)

[0101] Condition (8) is a condition for optimizing the light incident angle on the image plane.

[0102] When EXP / IH is below the lower limit of condition (8), there is a tendency for the light incident angle to become lower, but there is a tendency for it to be difficult to shorten the overall length of the optical system to make it smaller. In addition, when EXP / IH is above the upper limit of condition (8), there is a tendency for the light incident angle to become higher. Therefore, by satisfying condition (8), the imaging lens 100 can achieve miniaturization.

[0103] In addition, the imaging lens 100 of each embodiment satisfies condition (9) when the focal length of the first lens L1 is set to f1 and the focal length of the second lens is set to f2.

[0104] 0.01 < |f1 / f2| < 0.40 ··· (9)

[0105] Condition (9) is a condition related to the balance between the focal lengths of the first lens L1 and the second lens L2.

[0106] When |f1 / f2| is below the lower limit of condition (9), the lens power of f2 becomes weaker relative to f1, so it is easy for spherical aberration and distortion aberration to become insufficiently corrected, making it difficult to achieve high performance. In addition, when |f1 / f2| is above the upper limit of condition (9), astigmatism tends to increase, so this is not preferred. Therefore, the imaging lens 100 can achieve high performance by satisfying condition (9).

[0107] In addition, when the focal length of the first lens L1 is set to f1 and the focal length of the third lens L3 is set to f3 in the imaging lens 100 of each embodiment, condition (10) is satisfied.

[0108] 0.25 < f3 / f1 < 0.55 ··· (10)

[0109] Condition (10) is a conditional expression related to the positive power of the first lens L1 and the positive power of the third lens L3.

[0110] When f3 / f1 is below the lower limit of condition (10), astigmatism tends to be excessive, and distortion aberration and coma aberration are also generated to a large extent, making it difficult to achieve the desired performance. In addition, when f3 / f1 is above the upper limit of condition (10), spherical aberration tends to be too small, so the balance with astigmatism is broken, making it difficult to achieve the desired performance.

[0111] In addition, when the focal length of the third lens L3 is set to f3 and the focal length of the fourth lens L4 is set to f4 in the imaging lens 100 of each embodiment, condition (11) is satisfied.

[0112] 0.7 < |f3 / f4| < 1.3 ··· (11)

[0113] Condition (11) is a conditional expression related to the lens power of the third lens L3 and the lens power of the fourth lens L4.

[0114] When f3 / f4 is below the lower limit of condition (11), astigmatism tends to be excessive, and distortion aberration also tends to increase, so it is difficult to achieve the desired performance. In addition, when f3 / f4 is above the upper limit of condition (11), the overall focal length becomes larger, tending to have a narrow field angle, so there is a tendency to improve astigmatism and distortion aberration, but since spherical aberration tends to increase, it is difficult to achieve the desired performance. Therefore, the imaging lens 100 can achieve a balance between short form (low profile) and high performance by satisfying condition (11).

[0115] In addition, in the imaging lenses 100 of Embodiments 1 to 5, when the second lens L2 has negative power, the focal length of the second lens L2 is set to f2, and the focal length of the entire optical system is set to f, condition (16) is satisfied.

[0116] −0.2 < f / f2 < −0.0 ··· (16)

[0117] Condition (16) is a conditional expression related to the focal length of the second lens L2 and the focal length of the entire optical system.

[0118] When f / f2 is below the lower limit of condition (16), the lens power of f2 relative to f becomes stronger, and astigmatism and distortion aberration are likely to be insufficiently corrected, so it is difficult to achieve high performance. Therefore, the imaging lens 100 can achieve high performance by satisfying condition (16).

[0119] In addition, the imaging lens 100 of Embodiments 6 to 10 has a positive power for the second lens L2. When the focal length of the second lens L2 is set to f2 and the focal length of the entire optical system is set to f, condition (16) is satisfied.

[0120] 0.0 < f / f2 < 0.25 ··· (17)

[0121] Condition (17) is a conditional expression related to the focal length of the second lens L2 and the focal length of the entire optical system.

[0122] When f / f2 is above the upper limit of condition (17), the lens power of f2 relative to f becomes stronger, and astigmatism and distortion aberration are likely to be insufficiently corrected, so it is difficult to achieve high performance. Therefore, the imaging lens 100 can achieve high performance by satisfying condition (17).

[0123] 〔Imaging device〕

[0124] Next, an embodiment of an information processing device (PC) having an imaging device using the imaging lens 100 of each embodiment as an imaging optical system will be described.

[0125] Figure 21 is a diagram showing a schematic configuration of an information processing device having an imaging device with the imaging lens 100 of each embodiment. Figure 22 is a diagram showing Figure 21 the schematic configuration of the imaging device. Figure 23 is a block diagram showing the functional configuration of an information processing device having an imaging device with the imaging lens of each embodiment.

[0126] Figures 21 - 23 The information processing device 30 shown at least includes 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.

[0127] The photographing device 31 generates a photographing signal by photographing a prescribed field of view area under the control of the control unit 34, and outputs the photographing signal to the signal processing unit 32. As Figure 22 shown, the photographing device 31 includes at least a cover 311, the photographing lens 100 of each embodiment, and a single photographing element 312. The photographing device 31 is disposed on the front side of the information processing device 30. Specifically, the photographing device 31 is disposed at a position where the user of the information processing device 30 can be photographed. Of course, the photographing device 31 can appropriately change the disposition position according to the shape, size, and usage mode of the information processing device 30.

[0128] The cover 311 is constituted of a glass cover or the like which is a component for preventing dirt and dust on the photographing lens 100. Further, the information processing device 30 may further provide a cover or the like for opening and closing according to the user's operation to the cover 311.

[0129] The single photographing element 312 receives the image of the photographed object imaged by the photographing lens 100, and generates a photographing signal by performing photoelectric conversion. The single photographing element 312 is constituted of a CCD sensor, a CMOS sensor, or the like. Preferably, the single photographing element 312 arranges effective pixels of 8 million pixels or more, so-called 4K or more (3840×2160 or more), in a two-dimensional matrix shape.

[0130] The signal processing unit 32 performs A / D conversion processing or the like on the photographing signal input from the single photographing element 312 under the control of the control unit 34 to convert it into a digital photographing signal and outputs it to the image processing unit 33. For example, the signal processing unit 32 is constituted of a DSP (Digital Signal Processor).

[0131] The image processing unit 33 performs prescribed image processing on the digital photographing signal input from the signal processing unit 32 under the control of the control unit 34 and outputs it to the display unit 35 or the storage unit 36. For example, the image processing unit 33 is constituted of a GPU (Graphics Processing Unit). Here, the prescribed image processing refers to electrical correction processing of shadows, white balance adjustment processing, trimming processing of the center portion of the image, noise reduction processing, and the like.

[0132] 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 constituted of a CPU or an FPGA (Field-Programmable Gate Array). The memory is constituted of a RAM (Random Access Memory) or a ROM (Read Only Memory).

[0133] Under the control of the control unit 34, the display unit 35 displays the video during shooting for which the image processing unit 33 has performed image processing, the captured image, the still image corresponding to the image signal stored in the storage unit 36, and various information related to the information processing device 30.

[0134] The storage unit 36 stores various information related to the information processing device 30, the programs executed by the information processing device 30, and the captured signals (RAW data or JPEG data) captured by the imaging device 31. The storage unit 36 is constituted by, for example, a flash memory, an SSD (Solid State Drive), an HDD (Hard Disk Drive), and a memory card.

[0135] Under the control of the control unit 34, the communication unit 37 transmits the captured signal captured by the imaging device 31 to the outside via a network according to a prescribed communication standard, and receives various information input from the outside. The communication unit 37 uses, for example, communication standards based on 3GPP (registered trademark), 4G, LTE, 5G, WiMAX, and Wi-Fi (registered trademark) established by IEEE.

[0136] The input unit 38 accepts the operation input of the user and outputs operation information corresponding to the accepted operation to the control unit 34. The input unit 38 is constituted by, for example, a touch panel, a keyboard, and a mouse.

[0137] Under the control of the control unit 34, the audio input / output unit 39 accepts the input of external sound, converts it into an audio signal, and outputs it to the storage unit 36 or the communication unit 37. Further, under the control of the control unit 34, the audio input / output unit 39 converts the 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 constituted by a microphone and a speaker.

[0138] The information processing device 30 configured as described above can communicate with an external device in high definition of 4K via Web communication via a network using the imaging device 31 having the imaging lens 100.

[0139] In addition, in the embodiment, a PC is described as an example of the information processing device 30, but the imaging device 31 can be applied to, for example, imaging devices of tablet terminals, mobile phones, etc. Of course, the imaging device 31 can also be applied to Web cameras that can communicate with a PC or the like by wire or wirelessly.

[0140] According to the embodiment described above, an information processing device with a wide field of view angle, bright, high performance, and small size can be realized.

[0141] In addition, according to the embodiment, a semi-field of view angle of approximately 50° can be achieved with four lenses.

[0142] In addition, according to the embodiment, since the photographing lens 100 can achieve a wide-angle field of view angle, has a small F-number, and is a high-performance and small-sized photographing lens, in the case of video shooting, it can cope with shooting in various environments such as a dark environment and high-speed shooting speed.

[0143] In addition, according to the embodiment, since it is possible to achieve a wide-angle field of view angle and a bright, high-performance and small-sized photographing lens, the matching between the incident angle in the light-receiving element of the single photographing element and the light incident on the light-receiving surface can be improved on the image side.

[0144] In addition, according to the embodiment, since a photographing lens with a bright, high-performance and small-sized semi-field of view angle of approximately 50° can be constituted by four lenses, for example, it can be used as a single-focus lens used in mobile phones such as smart phones and PCs. Therefore, in the case of video shooting requiring a high pixel count of 4K or more (3840×2160 or more), compared with conventional photographing lenses, sufficient aberration correction can be performed, and the required performance can be satisfied.

[0145] In addition, according to the embodiment, since a photographing lens with a bright, high-performance and small-sized semi-field of view angle of approximately 50° can be constituted by four lenses, the overall length of the photographing lens 100 in the optical axis direction can be shortened, and the lens diameter can also be reduced, thereby enabling miniaturization. As a result, the refractive power of the miniaturized lens becomes smaller, and the influence of manufacturing errors and assembly errors can be reduced. As a result, productivity can be improved, and production costs can be suppressed.

[0146] In addition, by appropriately combining a plurality of constituent elements disclosed in the information processing apparatus according to the embodiment of the present disclosure, various inventions can be formed. For example, several constituent elements may be deleted from all the constituent elements described in the information processing apparatus according to the embodiment of the present disclosure above. Also, the constituent elements described in the information processing apparatus according to the embodiment of the present disclosure above may be appropriately combined.

[0147] In addition, in the information processing apparatus according to the embodiment of the present disclosure, the above-mentioned "section" can be replaced with "unit" or "circuit", etc. For example, the control section can be replaced with a control unit or a control circuit.

[0148] In addition, the program executed by the information processing apparatus according to the embodiment of the present disclosure is recorded in a computer-readable recording medium such as a CD-ROM, a floppy disk (FD), a CD-R, a DVD (Digital Versatile Disk), a USB medium, and a flash memory in a file data format that can be installed or executed and provided.

[0149] In addition, a program executed by the information processing apparatus according to an embodiment of the present disclosure may also be configured to be stored in a computer connected to a network such as the Internet and provided by downloading it via the network.

[0150]

Embodiment

[0151] Hereinafter, Embodiments 1 to 10 of the photographing lens 100 corresponding to Embodiments 1 to 10 will be shown.

[0152] The meanings of the symbols in each embodiment are as follows.

[0153] f: Focal length of the entire lens system

[0154] fl: Focal length of each lens

[0155] FNo.: Numerical aperture (F-number)

[0156] R: Curvature radius of the surface

[0157] D: Surface interval

[0158] Nd: Refractive index for d-line

[0159] Vd: Abbe number for d-line

[0160] SD: Effective radius

[0161] When the depth in the optical axis direction is set to X, the height from the optical axis is set to H, the paraxial curvature radius is set to R, the conic constant is set to k, and the higher-order aspherical coefficient is set to CN (N is an even number of 4 or more), the aspherical surface is represented by the following well-known formula (15) using the aspherical coefficient.

[0162] X = (H 2 / R) / [1 + {1 - k(H / r) 2} 1 / 2

[0163] + Σ N＝4:even CNH N ··· (15)

[0164] Here, Σ N≧4:even means the sum for N being an even number of 4 or more.

[0165] [Embodiment 1]

[0166] f = 2.1 mm, FNo. = 2.2, HFOV = 45°

[0167] The data of Embodiment 1 is shown in Table 1.

[0168]

Table 1

[0169]

[0170] The data of the aspherical surface is as shown below.

[0171]

Table 2

[0172]

[0173] In the above description of the aspherical surface, for example, "2.1143.E-02" means "2.1143 * 10 －2 ". The same applies to other embodiments below.

[0174] The parameter values of each condition are as follows. In addition, EP: entrance pupil position is also described in Table 3.

[0175]

Table 3

[0176] Item Value f 2.13 Fno 2.2 OAL 2.90 IH 2.305 EfD1 0.95 Half FOV 45.00 EP 0.00 EXP -1.633 f1 2.83 f2 -12.3 f3 1.37 f4 -1.28 N1 1.5365 N2 1.6606 N3 1.5365 N4 1.6328

[0177] In this table, in addition to conditional expressions (1) to (11), (16), (12) to (14) are also described as references.

[0178]

Table 4

[0179] Conditional expression Value Lower limit Upper limit (1) f / f1 0.753 0.45 0.80 (2) |f4 / f1| 0452 0.25 0.50 (3) N1 < N4 Refer to Table 3 (4) N1 1.53650 1.49 1.55 (5) N4 1.63277 1.63 1.67 (6) f / OAL 0.734 0.60 0.75 (7) OAL / EfD1 3.051 2.9 3.6 (8) EXP / IH -0.708 -0.94 -0.70 (9) |f1 / f2| 0.230 0.01 0.40 (10) f3 / f1 0.484 0.25 0.55 (11) |f3 / f4| 1.070 0.7 1.3 (12) |f4 / f2| 0.104 0.01 0.15 (13) |f3 / f2| 0.111 0.01 0.17 (14) OAL / 2 * IH 0.629 0.61 0.65 (16) f / f2 -0.173 -0.2 -0.0

[0180] In addition, the meanings of the conditional expressions (12) to (14) are as follows.

[0181] 0.01 < |f4 / f2| < 0.15 ··· (12)

[0182] Regarding conditional expression (12), f2 represents the focal length of the second lens L2, f4 represents the focal length of the fourth lens L4, and it is a condition for the balance of the focal lengths of the second lens L2 and the fourth lens L4. Within the range of conditional expression (12), high performance can be achieved. When it is below the lower limit of the conditional expression, astigmatism becomes larger, and when it is above the upper limit of conditional expression (12), spherical aberration becomes larger. Therefore, it is preferably within the range that satisfies the conditional expression.

[0183] 0.01 < |f3 / f2| < 0.17 ··· (13)

[0184] Regarding conditional expression (13), f2 represents the focal length of the second lens L2, f3 represents the focal length of the third lens L3, and it is a condition for the balance of the focal lengths of the second lens L2 and the third lens L3.

[0185] High performance can be achieved within the range of conditional expression (13). When below the lower limit of conditional expression (13), astigmatism becomes large, and when above the upper limit of conditional expression (13), spherical aberration becomes large. Therefore, it is preferable to satisfy the range of the conditional expression.

[0186] The present disclosure is characterized in that the power of the second lens L2 is weaker compared to the power of other lenses. However, the present disclosure can effectively correct astigmatism, spherical aberration, and distortion aberration by disposing a positive or negative lens having a relatively weaker power compared to other lenses in the second lens L2.

[0187] 0.61 < OAL / 2 * IH < 0.65 ··· (14)

[0188] Regarding conditional expression (14), OAL represents the overall optical length, and IH represents the image height, that is, the image circle of the so-called optical system, showing the ratio of the overall optical length to the image circle. As in conditional expression (14), the overall optical length is 0.61 to 0.65 with respect to the image circle, and it can be seen that the photographing lens 100 of the present disclosure is low-profile.

[0189] In addition, regarding these conditional expressions (12) to (14), they are also applied after Example 2.

[0190] In addition, aspherical surfaces are used in the first lens L1 to the fourth lens L4 in each embodiment, and aberrations are well corrected by the aspherical surfaces.

[0191] The aberration diagrams, MTF, and distortion grids related to the above-described Example 1 are as Figures 2A - 2C shown. However, as is clear from each figure, the performance is good.

[0192] [Example 2]

[0193] f = 1.9 mm, FNo. = 2.0, HFOV = 47°

[0194] The data of Example 2 are shown in Table 5.

[0195] [Table 5]

[0196]

[0197] The data of the aspherical surface are as follows.

[0198] [Table 6]

[0199]

[0200] The parameter values of each condition are as follows.

[0201] [Table 7]

[0202] Item Value F 1.94 Fno 2.0 OAL 2.90 IH 2.305 EfD1 0.967 Half FOV 47.31 EP 0.00 EXP -1.95 f1 3.55 f2 -29.94 f3 1.14 f4 -1.23 N1 1.5094 N2 1.6328 N3 1.5094 N4 1.6328

[0203]

Table 8

[0204] Conditional expression Value Lower limit Upper limit (1) f / f1 0.545 0.45 0.80 (2) |f4 / f1| 0.348 0.25 0.50 (3) N1 < N4 Refer to Table 7 (4) N1 1.5094 1.49 1.55 (5) N4 1.6328 1.63 1.67 (6) f / OAL 0.667 0.60 0.75 (7) OAL / EfD1 2.998 2.9 3.6 (8) EXP / IH -0.846 -0.94 -0.70 (9) |f1 / f2| 0.119 0.01 0.40 (10) f3 / f1 0.321 0.25 0.55 (11) |f3 / f4| 0.923 0.7 1.3 (12) |f4 / f2| 0.041 0.01 0.15 (13) |f3 / f2| 0.038 0.01 0.17 (14) OAL / 2 * IH 0.629 0.61 0.65 (16) f / f2 -0.065 -0.2 -0.0

[0205] These aberration diagrams, MTF, and distortion grids are as Figures 4A - 4C shown, but as is clear from each diagram, the performance is good.

[0206] [Example 3]

[0207] f = 1.8 mm, FNo. = 2.2, HFOV = 51°

[0208] The data of Example 3 are shown in Table 9.

[0209]

Table 9

[0210]

[0211] The data of the aspherical surface are as follows.

[0212]

Table 10

[0213]

[0214] The parameter values for each condition are as follows.

[0215]

Table 11

[0216] Item Value F 1.78 Fno 2.2 OAL 2.90 IH 2.31 EfD1 0.81 Half FOV 51.43 EP 0.00 EXP -2.14 f1 3.70 f2 -9.91 f3 0.97 f4 -1.19 N1 1.5365 N2 1.6328 N3 1.5365 N4 1.6328

[0217]

Table 12

[0218] Conditional expression Value Lower limit Upper limit (1) f / f1 0.482 0.45 0.80 (2) |f4 / f1| 0.321 0.25 0.50 (3) N1 < N4 Refer to Table 11 (4) N1 1.5365 1.49 1.55 (5) N4 1.6328 1.63 1.67 (6) f / OAL 0.614 0.60 0.75 (7) OAL / EfD1 3.584 2.9 3.6 (8) EXP / IH -0.926 -0.94 -0.70 (9) |f1 / f2| 0.373 0.01 0.40 (10) f3 / f1 0.263 0.25 0.55 (11) |f3 / f4| 0.819 0.7 1.3 (12) |f4 / f2| 0.120 0.01 0.15 (13) |f3 / f2| 0.098 0.01 0.17 (14) OAL / 2 * IH 0.629 0.61 0.65 (16) f / f2 -0.180 -0.2 -0.0

[0219] These aberration diagrams, MTF, and distortion grids are as Figures 6A - 6C shown, but as is clear from each diagram, the performance is good.

[0220] [Example 4]

[0221] f = 1.9 mm, FNo. = 2.0, HFOV = 48°

[0222] The data of Example 4 are shown in Table 13.

[0223]

Table 13

[0224]

[0225] The data of the aspherical surface are as follows.

[0226]

Table 14

[0227]

[0228] The parameter values for each condition are as follows.

[0229]

Table 15

[0230] Item Value f 1.93 Fno 2.0 OAL 2.90 IH 2.305 EfD1 0.966 Half FOV 47.56 EP 0.00 EXP -1.81 f1 3.66 f2 -32.79 f3 1.33 f4 -1.49 N1 1.5365 N2 1.6422 N3 1.5365 N4 1.6422

[0231]

Table 16

[0232] Conditional expression Value Lower limit Upper limit (1) f / f1 0.527 0.45 0.80 (2) |f4 / f1| 0.406 0.25 0.50 (3) N1 < N4 Refer to Table 15 (4) N1 1.5365 1.49 1.55 (5) N4 1.6422 1.63 1.67 (6) f / OAL 0.666 0.60 0.75 (7) OAL / EfD1 3.004 2.9 3.6 (8) EXP / IH -0.785 -0.94 -0.70 (9) |f1 / f2| 0.112 0.01 0.40 (10) f3 / f1 0.364 0.25 0.55 (11) |f3 / f4| 0.896 0.7 1.3 (12) |f4 / f2| 0.045 0.01 0.15 (13) |f3 / f2| 0.041 0.01 0.17 (14) OAL / 2 * IH 0.629 0.61 0.65 (16) f / f2 -0.059 -0.2 -0.0

[0233] These aberration diagrams, MTF, and distortion grids are as Figures 8A - 8C shown, but as is clear from each aberration diagram, the performance is good.

[0234] [Example 5]

[0235] f = 1.9 mm, FNo. = 2.0, HFOV = 48°

[0236] The data for Example 5 are shown in Table 17.

[0237]

Table 17

[0238]

[0239] The data for the aspherical surface are as follows.

[0240]

Table 18

[0241]

[0242] The parameter values for each condition are as follows.

[0243]

Table 19

[0244] Item Value F 1.93 Fno 2.0 OAL 2.90 IH 2.30 EfD1 0.962 Half FOV 47.56 EP 0.00 EXP -1.87 f1 3.49 f2 -16.24 f3 1.31 f4 -1.51 N1 1.5168 N2 1.6422 N3 1.5365 N4 1.6422

[0245]

Table 20

[0246] Conditional expression Value Lower limit Upper limit (1) f / f1 0.552 0.45 0.80 (2) |f4 / f1| 0.434 0.25 0.50 (3) N1 < N4 Refer to Table 19 (4) N1 1.5168 1.49 1.55 (5) N4 1.6422 1.63 1.67 (6) f / OAL 0.664 0.60 0.75 (7) OAL / EfD1 3.013 2.9 3.6 (8) EXP / IH -0.815 -0.94 -0.70 (9) |f1 / f2| 0.215 0.01 0.40 (10) f3 / f1 0.376 0.25 0.55 (11) |f3 / f4| 0.867 0.7 1.3 (12) |f4 / f2| 0.093 0.01 0.15 (13) |f3 / f2| 0.081 0.01 0.17 (14) OAL / 2 * IH 0.632 0.61 0.65 (16) f / f2 -0.119 -0.2 -0.0

[0247] These aberration diagrams, MTF, and distortion grids are as Figures 10A - 10C shown, but as is clear from each aberration diagram, the performance is good.

[0248] [Example 6]

[0249] f = 2.0 mm, FNo. = 2.2, HFOV = 48°

[0250] The data for Example 6 are shown in Table 21.

[0251]

Table 21

[0252]

[0253] The data of the aspherical surface is as follows.

[0254]

Table 22

[0255]

[0256] The parameter values of each condition are as follows.

[0257]

Table 23

[0258] Item Value f 2.03 Fno 2.2 OAL 2.90 IH 2.31 EfD1 0.908 Half FOV 47.90 EP 0.00 EXP -1.84 f1 3.36 f2 16.34 f3 1.41 f4 -1.45 N1 1.5365 N2 1.6328 N3 1.5365 N4 1.6652

[0259]

Table 24

[0260] Conditional expression Value Lower limit Upper limit (1) f / f1 0.606 0.45 0.80 (2) |f4 / f1| 0.432 0.25 0.50 (3) N1 < N4 Refer to Table 23 (4) N1 1.5365 1.49 1.55 (5) N4 1.6652 1.63 1.67 (6) f / OAL 0.701 0.60 0.75 (7) OAL / EfD1 3.194 2.9 3.6 (8) EXP / IH -0.796 -0.94 -0.70 (9) |f1 / f2| 0.205 0.01 0.40 (10) f3 / f1 0.420 0.25 0.55 (11) |f3 / f4| 0.972 0.7 1.3 (12) |f4 / f2| 0.089 0.01 0.15 (13) |f3 / f2| 0.086 0.01 0.17 (14) OAL / 2*IH 0.629 0.61 0.65 (17) f / f2 0.124 0.01 0.25

[0261] These aberration diagrams, MTF, and distortion grids are as Figures 12A to 12C shown, but as is clear from each aberration diagram, the performance is good.

[0262] [Example 7]

[0263] f = 2.0 mm, FNo. = 2.2, HFOV = 48°

[0264] The data of Example 7 is shown in Table 25.

[0265]

Table 25

[0266]

[0267] The data of the aspherical surface is as follows.

[0268]

Table 26

[0269]

[0270] The parameter values of each condition are as follows.

[0271]

Table 27

[0272] Item Value f 2.03 Fno 2.2 OAL 2.90 IH 2.304 EfD1 0.904 Half FOV 47.97 EP 0.00 EXP -1.86 f1 3.38 f2 97.3 f3 0.93 f4 -0.91 N1 1.5365 N2 1.6328 N3 1.5365 N4 1.6328

[0273]

Table 28

[0274] Condition formula Value Lower limit Upper limit (1) f / f1 0.599 0.45 0.80 (2) |f4 / f1| 0.270 0.25 0.50 (3) N1 < N4 Refer to Table 27 (4) N1 1.5365 1.49 1.55 (5) N4 1.6328 1.63 1.67 (6) f / OAL 0.699 0.60 0.75 (7) OAL / EfD1 3.207 2.9 3.6 (8) EXP / IH -0.808 -0.94 -0.70 (9) |f1 / f2| 0.035 0.01 0.40 (10) f3 / f1 0.274 0.25 0.55 (11) |f3 / f4| 1.017 0.7 1.3 (12) |f4 / f2| 0.009 0.01 0.15 (13) |f3 / f2| 0.010 0.01 0.17 (14) OAL / 2*IH 0.629 0.61 0.65 (17) f / f2 0.021 0.01 0.25

[0275] These aberration diagrams, MTF, and distortion grids are as Figures 14A to 14C shown, but as is clear from each aberration diagram, the performance is good.

[0276] [Example 8]

[0277] f = 2.1 mm, FNo. = 2.2, HFOV = 47°

[0278] The data of Example 8 is shown in Table 29.

[0279] [Table 29]

[0280]

[0281] The data of the aspheric surface is as follows.

[0282] [Table 30]

[0283]

[0284] The parameter values of each condition are as follows.

[0285] [Table 31]

[0286] Item Value f 2.09 Fno 2.2 OAL 2.90 IH 2.31 EfD1 0.932 Half FOV 47.00 EP 0.00 EXP -1.78 f1 3.30 f2 17.0 f3 1.21 f4 -1.15 N1 1.5365 N2 1.6328 N3 1.5365 N4 1.6652

[0287] [Table 32]

[0288] Condition formula Value Lower limit Upper limit (1) f / f1 0.633 0.45 0.80 (2) |f4 / f1| 0.350 0.25 0.50 (3) N1 < N4 Refer to Table 31 (4) N1 1.5365 1.49 1.55 (5) N4 1.6652 1.63 1.67 (6) f / OAL 0.720 0.60 0.75 (7) OAL / EfD1 3.110 2.9 3.6 (8) EXP / IH -0.770 -0.94 -0.70 (9) |f1 / f2| 0.194 0.01 0.40 (10) f3 / f1 0.367 0.25 0.55 (11) |f3 / f4| 1.049 0.7 1.3 (12) |f4 / f2| 0.068 0.01 0.15 (13) |f3 / f2| 0.071 0.01 0.17 (14) OAL / 2*IH 0.629 0.61 0.65 (17) f / f2 0.123 0.01 0.25

[0289] These aberration diagrams, MTF, and distortion grids are as Figures 16A to 16C shown, but as is clear from each aberration diagram, the performance is good.

[0290] [Example 9]

[0291] f = 2.1 mm, FNo. = 2.2, HFOV = 46.5°

[0292] The data of Example 9 is shown in Table 33.

[0293] [Table 33]

[0294]

[0295] The data of the aspheric surface is as follows.

[0296] [Table 34]

[0297]

[0298] The parameter values of each condition are as follows.

[0299] [Table 35]

[0300] Item Value f 2.12 Fno 2.2 OAL 2.90 IH 2.29 EfD1 0.947 Half FOV 46.50 EP 0.000 EXP -1.77 f1 3.22 f2 15.8 f3 1.21 f4 -1.12 N1 1.5365 N2 1.6328 N3 1.5365 N4 1.6328

[0301] [Table 36]

[0302] Condition formula Value Lower limit Upper limit (1) f / f1 0.659 0.45 0.80 (2) |f4 / f1| 0.348 0.25 0.50 (3) N1 < N4 Refer to Table 34 (4) N1 1.5365 1.49 1.55 (5) N4 1.6328 1.63 1.67 (6) f / OAL 0.732 0.60 0.75 (7) OAL / EfD1 3.062 2.9 3.6 (8) EXP / IH -0.774 -0.94 -0.70 (9) |f1 / f2| 0.204 0.01 0.40 (10) f3 / f1 0.375 0.25 0.55 (11) |f3 / f4| 1.078 0.7 1.3 (12) |f4 / f2| 0.071 0.01 0.15 (13) |f3 / f2| 0.076 0.01 0.17 (14) OAL / 2*IH 0.633 0.61 0.65 (17) f / f2 0.134 0.01 0.25

[0303] These aberration diagrams, MTF, and distortion grids are asFigures 18A to 18C As shown, but as is clear from each aberration diagram, the performance is good.

[0304] [Example 10]

[0305] f = 2.1 mm, FNo. = 2.2, HFOV = 46.5°

[0306] The data of Example 10 are shown in Table 37.

[0307]

Table 37

[0308]

[0309] The data of the aspherical surface are as follows.

[0310]

Table 38

[0311]

[0312] The parameter values of each condition are as follows.

[0313]

Table 39

[0314] Item Value f 2.12 Fno 2.2 OAL 2.90 IH 2.30 EfD1 0.945 Half FOV 46.50 EP 0.00 EXP -1.62 f1 3.16 f2 9.73 f3 1.66 f4 -1.46 N1 1.5540 N2 1.6328 N3 1.5365 N4 1.6652

[0315]

Table 40

[0316] Condition formula Value Lower limit Upper limit (1) f / f1 0.669 0.45 0.80 (2) |f4 / f1| 0.461 0.25 0.50 (3) N1 < N4 Refer to Table 38 (4) N1 1.5540 1.49 1.55 (5) N4 1.6652 1.63 1.67 (6) f / OAL 0.730 0.60 0.75 (7) OAL / EfD1 3.069 2.9 3.6 (8) EXP / IH -0.706 -0.94 -0.70 (9) |f1 / f2| 0.325 0.01 0.40 (10) f3 / f1 0.526 0.25 0.55 (11) |f3 / f4| 1.141 0.7 1.3 (12) |f4 / f2| 0.150 0.01 0.15 (13) |f3 / f2| 0.171 0.01 0.17 (14) OAL / 2*IH 0.630 0.61 0.65 (17) f / f2 0.218 0.01 0.25

[0317] These aberration diagrams, MTF, and distortion grids are as Figures 20A to 20C shown, but as is clear from each aberration diagram, the performance is good.

[0318] As above, as in Examples 1 to 10, Figures 2A to 2C , Figures 4A to 4C , Figures 6A to 6C , Figures 8A to 8C , Figures 10A to 10C , Figures 12A to 12C , Figures 14A to 14C , Figures 16A to 16C , Figures 18A to 18C and Figures 20A to 20C as shown, the photographing lens 100 of the present disclosure is bright, high-performance, and miniaturized (shortened in the optical axis direction), and the half field of view angle is realized to be about 50° by four lenses, and it is also clear that it is suitable as a photographing device, particularly a photographing device for a laptop PC.

[0319] As above, several embodiments of the present application have been described in detail with reference to the drawings, but these embodiments are examples, and the present invention can be implemented in other ways in which various modifications and improvements are made based on the knowledge of those skilled in the art, starting from the manner described in the disclosure column of the present invention.

Claims

1. A photographing lens, wherein: have: The first to fourth lenses are arranged in order from the object side; and The aperture stop, which is closest to the object, The first lens is a positive meniscus lens with its convex surface facing the object side. The second lens is a lens having an inflection point on at least one surface and having a small deviation ratio. The third lens is a positive lens having a convex surface facing the image plane and having an inflection point at the periphery of the lens. The fourth lens is a negative lens having a concave surface on the image side and an inflection point at the periphery. When the focal length of the first lens is set to f1, the focal length of the fourth lens is set to f4, and the focal length of the entire optical system is set to f, conditions (1) and (2) are satisfied, that is: 0.45<|f / f1|<0.80···(1) 0.25<|f4 / f1|<0.50···(2).

2. The imaging lens according to claim 1, wherein: When the refractive index of the material of the first lens for the d-line is set to N1, and the refractive index of the material of the fourth lens for the d-line is set to N4, condition (3) is satisfied, that is: N1<N4···(3).

3. The imaging lens according to claim 1, wherein: When the refractive index of the material of the first lens for the d-line is set to N1, condition (4) is satisfied, that is: 1.49＜N1＜1.55···(4)。 4. The imaging lens according to claim 1, wherein: When the refractive index of the material of the fourth lens for d-line is set to N4, condition (5) is satisfied, that is: 1.63＜N4＜1.67···(5)。 5. The photographing lens according to claim 1, wherein: When the focal length of the entire optical system is set to f and the total length of the optical system is set to OAL, condition (6) is satisfied, that is: 0.60<f / OAL<0.75···(6).

6. The photographing lens according to claim 1, wherein: When the total optical length is set to OAL and the optical effective diameter of the lens closest to the object is set to EfD1, condition (7) is satisfied, that is: 2.9<OAL / EfD1<3.6···(7).

7. The photographing lens according to claim 1, wherein: When the exit pupil position is set to EXP and the image height is set to IH, condition (8) is satisfied, that is: -0.94<EXP / IH<-0.70···(8).

8. The photographing lens according to claim 1, wherein: When the focal length of the first lens is set to f1 and the focal length of the second lens is set to f2, condition (9) is satisfied, that is: 0.01<|f1 / f2|<0.40···(9).

9. The photographing lens according to claim 1, wherein: When the focal length of the first lens is set to f1 and the focal length of the third lens is set to f3, condition (10) is satisfied: 0.25<f3 / f1<0.55···(10).

10. The photographing lens according to claim 1, wherein: When the focal length of the third lens is set to f3 and the focal length of the fourth lens is set to f4, condition (11) is satisfied, that is: 0.7<|f3 / f4|<1.3···(11).

11. The photographing lens according to claim 1, wherein: The second lens has negative power. When the focal length of the second lens is set to f2 and the focal length of the entire optical system is set to f, condition (16) is satisfied, that is: -0.2<f / f2<-0.0···(16).

12. The photographing lens according to claim 1, wherein: The second lens has positive power. When the focal length of the second lens is set to f2 and the focal length of the entire optical system is set to f, condition (17) is satisfied, that is: 0.0<f / f2<0.25···(17).

13. A photographing device, wherein: have: The imaging lens according to claim 1; and The single-body imaging element receives the image formed by the imaging lens and generates an imaging signal.

14. An information processing device, wherein: have: The photographing device according to claim 13; and The display unit displays an image corresponding to the imaging signal generated by the imaging device.

Images