Imaging lens, imaging device, and information processing device

Abstract

The present invention provides an imaging lens, imaging device, and information processing device that offer a wide angle of view, are bright, high-performance, and can be miniaturized. [Solution] The imaging lens 100 consists of a first lens L1 to a fifth lens L5 arranged in order from the object side, and an aperture diaphragm S between the first lens L1 and the second lens L2. The first lens L1 is either a positive or negative meniscus lens; the second lens L2 is a biconvex positive lens; the third lens L3 is a negative lens with its concave side facing the object; the fourth lens L4 is a positive meniscus lens with its convex side facing the image plane; and the fifth lens L5 is a negative meniscus lens with its convex side facing the object and its concave side facing the image plane.

Description

Technical Field

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

Background Art

[0002] In recent years, imaging devices such as digital still cameras, digital camcorders, and smartphone cameras, which include individual imaging elements such as CCDs (Charge Coupled Devices) and CMOSs (Complementary Metal Oxide Semiconductors) and imaging lenses, have become widespread.

[0003] The individual imaging elements used in those imaging devices are becoming higher in pixel count. Along with this increase in pixel count of the individual imaging elements, higher performance in optical performance is also demanded for the imaging lens.

[0004] In addition, in recent years, on personal computers (PCs) such as laptops and tablet-type terminal devices equipped with imaging devices, video distribution and communication are being carried out via the web. For this reason, in particular, imaging devices such as those mounted on the bezel portion of a laptop or under-display cameras (UDCs) hidden directly below the display of a tablet-type terminal device are also being miniaturized in consideration of portability.

[0005] In addition, the imaging devices demanded in the market are mainly those that achieve both high performance and miniaturization, and for the imaging lens, not only high performance but also miniaturization is demanded. For this reason, imaging lenses that achieve both high performance and miniaturization are known (see, for example, Patent Documents 1-4).

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

[0007] Incidentally, in recent years, when using imaging devices mounted on laptops and tablet devices to distribute videos and communicate via the web, there has been a demand for imaging lenses that are smaller, have a wider field of view, are brighter, and are higher performance than conventional imaging lenses, due to the need for mobility.

[0008] However, imaging lenses such as those described in Patent Documents 1 to 4 above do not consider placement in the bezel area of ​​a laptop or the space directly below the display of a tablet device. In order to achieve a wide-angle field of view, the overall length in the optical axis direction becomes longer, which increases the thickness of the bezel area and the display, making miniaturization difficult.

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

[0010] To solve the above-mentioned problems and achieve the objective, the imaging lens according to the first aspect of this disclosure comprises a first lens to a fifth lens arranged in order from the object side, and an aperture diaphragm between the first lens and the second lens, wherein the first lens is a positive meniscus lens or a negative meniscus lens, 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 plane 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 plane side, and when the focal length of the entire optical system is f, the total length of the lens is TTL, and the air gap between the first lens and the second lens is D1-2, conditions (1) and (2) 0.50 < f / TTL < 0.60 ···(1) 5.0e-3 < D1-2 / TTL < 4.0e-2 (2) It satisfies the condition.

[0011] Furthermore, the imaging device according to a second aspect of this disclosure comprises the above-mentioned imaging lens and a solid-state image sensor that receives the image formed by the imaging lens and generates an imaging signal.

[0012] Furthermore, the information processing device according to a third aspect of this disclosure comprises the imaging device and a display unit that displays an image corresponding to the imaging signal generated by the imaging device. [Effects of the Invention]

[0013] According to this disclosure, it is possible to provide a compact, wide-angle, bright, and high-performance imaging lens. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a diagram showing the lens configuration of an imaging lens according to Embodiment 1 of the present disclosure. [Figure 2A] Figure 2A is an aberration diagram of an imaging lens according to Embodiment 1 of the present disclosure. [Figure 2B] Figure 2B shows a distortion grid for an imaging lens according to Embodiment 1 of the present disclosure. [Figure 2C] Figure 2C shows the MTF of the imaging lens according to Embodiment 1 of the present disclosure. [Figure 3] Figure 3 is a diagram showing the lens configuration of the imaging lens according to Embodiment 2 of the present disclosure. [Figure 4A] Figure 4A is a diagram of the aberration of the imaging lens according to Embodiment 2 of the present disclosure. [Figure 4B] Figure 4B is the distortion lattice of the imaging lens according to Embodiment 2 of the present disclosure. [Figure 4C] Figure 4C shows the MTF of the imaging lens according to Embodiment 2 of the present disclosure. [Figure 5] Figure 5 is a diagram showing the lens configuration of the imaging lens according to Embodiment 3 of the present disclosure. [Figure 6A] Figure 6A is a diagram of the aberration of the imaging lens according to Embodiment 3 of the present disclosure. [Figure 6B] Figure 6B is the distortion lattice of the imaging lens according to Embodiment 3 of the present disclosure. [Figure 6C] Figure 6C shows the MTF of the imaging lens according to Embodiment 3 of the present disclosure. [Figure 7] Figure 7 is a diagram showing the lens configuration of the imaging lens according to Embodiment 4 of the present disclosure. [Figure 8A] Figure 8A is a diagram of the aberration of the imaging lens according to Embodiment 4 of the present disclosure. [Figure 8B] Figure 8B is the distortion lattice of the imaging lens according to Embodiment 4 of the present disclosure. [Figure 8C] Figure 8C shows the MTF of the imaging lens according to Embodiment 4 of the present disclosure. [Figure 9] Figure 9 is a diagram showing the lens configuration of the imaging lens according to Embodiment 5 of the present disclosure. [Figure 10A] Figure 10A is a diagram of the aberration of the imaging lens according to Embodiment 5 of the present disclosure. [Figure 10B] Figure 10B is the distortion lattice of the imaging lens according to Embodiment 5 of the present disclosure. [Figure 10C]Figure 10C shows the MTF of the imaging lens according to Embodiment 5 of this disclosure. [Figure 11] Figure 11 is a diagram showing the lens configuration of an imaging lens according to Embodiment 6 of the present disclosure. [Figure 12A] Figure 12A is an aberration diagram of an imaging lens according to Embodiment 6 of the present disclosure. [Figure 12B] Figure 12B shows a distortion grid for an imaging lens according to Embodiment 6 of the present disclosure. [Figure 12C] Figure 12C shows the MTF of the imaging lens according to Embodiment 6 of this disclosure. [Figure 13] Figure 13 is a diagram showing a schematic configuration of an information processing device equipped with an imaging device having an imaging lens according to each embodiment of the present disclosure. [Figure 14] Figure 14 shows a schematic configuration of the imaging device shown in Figure 13. [Figure 15] Figure 15 is a block diagram showing the functional configuration of an information processing device equipped with an imaging device having an imaging lens according to each embodiment of the present disclosure. [Modes for carrying out the invention]

[0015] The imaging lens, imaging device, and information processing device related to this disclosure will be described below with reference to the drawings. However, this disclosure is not limited to the embodiments described below. Furthermore, the figures referenced in the following description only provide a schematic representation of the shape, size, and positional relationships to the extent necessary to understand the content of this disclosure. In other words, this disclosure is not limited to the shapes, sizes, and positional relationships exemplified in the figures. Also, the same parts are denoted by the same reference numerals, and detailed descriptions are omitted.

[0016] [Embodiment] Figures 1, 3, 5, 7, 9, and 11 are cross-sectional views showing the lens configuration of the imaging lenses of Embodiments 1 to 6, respectively. 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 in each embodiment consists of a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 arranged in order from the object side to the image side, and an aperture diaphragm S (STOP) 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 either the first lens L1 to the fifth lens L5 or the aperture diaphragm S represent the surfaces of each lens or diaphragm. Hereinafter, these surfaces will be referred to sequentially as surfaces 1 to 11, 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 parallel plate equivalent to one composed of the cover glass of a solid-state image sensor and at least one of various filters. The incident side of the transparent parallel plate CG is referred to as surface 12, and the image side is referred to as surface 13.

[0019] The imaging lens 100 consists of, in order from the object side, an aperture diaphragm S, the first lens L1 to the fifth lens L5, with the aperture diaphragm S positioned between L1 and L2. In the imaging lens 100, the first lens L1 is a negative lens, and the second lens is a positive power lens. Furthermore, the imaging lens 100 consists of a third lens that is a negative lens, a fourth lens that is positive, and a fifth lens that is negative. Moreover, in the imaging lens 100, the lens closest to the object is a positive lens, and the lens closest to the image plane is a negative lens. In such a lens configuration, the angle of incidence of light tends to be low, and the angle of emission of light becomes large with the negative lens of the final fifth lens L5. However, by properly balancing the power 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 the lens may be aspherical. Furthermore, there may be an inflection point at the periphery of the lens. Here, the peripheral inflection point is a region on the surface 2 side that includes a position 60-80% of the way from the optical axis towards the outer edge relative to the aperture of the first lens L1. Embodiments 1, 4, 5, and 6 are negative lenses, specifically negative meniscus lenses with a concave surface facing the object side. Embodiments 2 and 3 are positive lenses, specifically positive meniscus lenses with a convex surface facing the object side.

[0021] The second lens L2 is constructed using a positive lens. Examples 1, 4, 5, and 6 are biconvex lenses, while Examples 2 and 3 are positive meniscus lenses that are convex towards the image plane. Furthermore, by using glass as the material for the second lens L2, it is possible to reduce chromatic aberration.

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

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

[0025] The first to fifth lenses L1 to L5 configured in this way may all be aspherical lenses, but the second lens L2 is a spherical lens as shown in each embodiment. Furthermore, by making the first lens L1 and the fifth lens L5, excluding the second lens L2, have an inflection point shape, aberrations can be corrected to a high degree while keeping the optical thickness (total length) of the imaging lens 100 thin.

[0026] Furthermore, regarding the lens material, as shown in the embodiments described later, optical plastic materials can be used, but for the second lens L2, glass material can be used. By using a glass lens made of this glass material, axial chromatic aberration can be improved compared to a plastic lens. This is evident from the spherical aberration of each color in each embodiment, where it is clear that chromatic aberration is well corrected by using a glass lens.

[0027] Figures 2A-2C, 4A-4C, 6A-6C, 8A-8C, 10A-10C, and 12A-12C show the longitudinal aberration diagrams, MTF, and distortion grids of the imaging lens 100 in embodiments 1-6, respectively. The spherical aberration diagram shows the amount of spherical aberration for the d line (yellow: wavelength 587.6 nm), the g line (blue: wavelength 435.8 nm), and the C line (red: 653.3 nm). In the astigmatism diagram, the solid line S shows the amount of astigmatism in the sagittal image plane, and the dashed line T shows the amount of astigmatism in the tangential image plane. Furthermore, the distortion diagram shows the amount of distortion for the d line only. Angle(deg) indicates the half-angle of view (°) of the image. Furthermore, regarding the distortion grid, the thin lines represent the paraaxial (Paraxial FOV) (ideal) grid, and the thick lines represent the actual (Actual FOV) grid. In addition, for MTF, the frequencies are 1 / 8 Ny, 1 / 4 Ny, and 1 / 2 Ny. At 1 / 8 Ny, the five-dot dashed line represents the sagittal image plane MTF, and the coarse dashed line represents the tangential image plane MTF. At 1 / 4 Ny, the three-dot dashed line represents the sagittal image plane MTF, and the fine dashed line represents the tangential image plane MTF. At 1 / 2 Ny, the two-dot dashed line represents the sagittal image plane MTF, and the fine dashed line represents the tangential image plane MTF.

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

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

[0030] If f / TTL is below the lower limit of condition (1), the overall focal length tends to be shorter, which is advantageous for wider angles of view, but astigmatism tends to be excessive and distortion also tends to be larger, making it difficult to achieve the desired performance. Also, if f / TTL is above the upper limit of condition (1), spherical aberration and astigmatism tend to be improved, but the angle of view becomes narrower and the overall length tends to be larger, which is undesirable because it does not allow for the achievement of the desired performance in the embodiments of this disclosure. For this reason, the imaging lens 100 can achieve a balance between miniaturization (low profile) and high performance by satisfying condition (1). That is, if condition (1) is not satisfied, when the imaging lens 100 is placed in the bezel of a display panel in a laptop or the like, it cannot be housed in the space of the thickness portion of the bezel or in the space that houses the display panel, causing the imaging lens 100 to protrude from the surface of the bezel or increasing the thickness of the bezel or the display panel. As a result, if condition (1) is not satisfied, when the imaging lens 100 is placed on the bezel or display panel, the thickness of the display panel or bezel increases, which impairs portability and aesthetics.

[0031] In each embodiment, the imaging lens 100 satisfies the following condition (2) when the total length of the lens is TTL and the air gap between the first lens and the second lens is D1-2. 5.0e-3 < D1-2 / TTL < 4.0e-2 (2)

[0032] Condition (2) concerns the overall length and the lens spacing between D1 and D2, and is a condition for maintaining a balance between overall length and aberrations.

[0033] If D1-2 / TTL is below the lower limit of condition (2), the overall length increases, and distortion is improved, but this tendency to increase the overall length is undesirable. If condition (2) is above the upper limit, the overall length decreases, but the balance of various aberrations is disrupted, making it difficult to achieve the desired performance.

[0034] Furthermore, the imaging lens 100 of each embodiment satisfies condition (3) when the focal length of the first lens L1 is f1 and the focal length of the entire optical system is f. 3.0 < |f1 / f| < 6.0 ···(3)

[0035] Condition (3) is a condition that defines the relationship between the focal length f1 of the first lens L1 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 this disclosure, the first lens L1, which has negative power on the object side of the aperture, is positioned on the object side in this wide-angle lens. Therefore, the power configuration of the first lens L1 is a necessary condition for balancing aberrations and angle of view. To properly control the angle of view and various aberrations while also achieving miniaturization, it is preferable to keep the configuration within the specified range.

[0037] If the value is below the lower limit of condition (3), the overall focal length of the system increases, but the focal length f1 of the first lens L1 decreases, causing astigmatism to shift to the positive side, which is undesirable. If the value is above the upper limit of condition (3), conversely, the focal length of f1 increases, causing astigmatism to shift to the under-biased side, disrupting the balance of aberrations, and also increasing the external size of the imaging lens 100, which is undesirable.

[0038] Furthermore, the imaging lens 100 of each embodiment satisfies condition (4) when the focal length of the first lens is f1 and the focal length of the second lens is f2. 3.5 < |f1 / f2| < 4.5 ···(4)

[0039] Condition (4) is a condition that defines the relationship between the focal length f1 of the first lens L1 and the focal length f2 of the second lens L2.

[0040] If condition (4) is below the lower limit, astigmatism tends to increase to the positive side and the astigmatism gap tends to increase, which is undesirable. Conversely, if condition (4) is above the upper limit, astigmatism tends to be under-exposed and the astigmatism gap increases, and spherical aberration tends to be over-exposed, resulting in increased field curvature, which is also undesirable. The imaging lens 100 can achieve high performance by satisfying condition (4).

[0041] Furthermore, the imaging lens 100 of each embodiment satisfies condition (4) when the focal length of the first lens L1 is f1 and the focal length of the fifth lens is f5. 4.5 < |f1 / f5| < 7.0 ···(5)

[0042] Condition (5) is a condition that defines the relationship between the focal length f1 of the first lens L1 and the focal length f5 of the fifth lens L5.

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

[0044] Furthermore, the imaging lens 100 of each embodiment satisfies condition (6) when the focal length of the fourth lens L4 is f4 and the focal length of the fifth lens is f5. 0.7 < |f4 / f5| < 1.2 ···(6)

[0045] Condition (6) defines the relationship between the focal length f4 of the fourth lens L4 and the focal length f5 of the fifth lens L5.

[0046] If condition (6) is below the lower limit, astigmatism tends to shift to the positive side and field curvature tends to be distorted. If condition (6) is above the upper limit, astigmatism shifts to the negative side and distortion aberration becomes insufficiently corrected to the negative side, which is undesirable. The imaging lens 100 can achieve high performance by satisfying condition (6).

[0047] Furthermore, in each embodiment, the imaging lens 100 satisfies condition (7) when the focal length of the lens group on the object side of the aperture diaphragm S is F1, and the focal length of the lens group on the image plane side of the aperture diaphragm S is F2. 3.5 < |F1 / F2| < 5.5 ···(7)

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

[0049] If condition (7) is below the lower limit, spherical aberration and astigmatism will shift to the positive side, and distortion will shift to the negative side, which is undesirable. If condition (7) is above the upper limit, astigmatism will become negative, resulting in insufficient correction, which is also undesirable. The imaging lens 100 can achieve high performance by satisfying condition (7).

[0050] Furthermore, the imaging lens 100 of each embodiment satisfies condition (8) when the exit pupil position is EXP and the image height is IH. 0.75 < |EXP / IH| < 1.0 ···(8)

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

[0052] When EXP / IH is below the lower limit of condition (8), the angle of incidence of light tends to be high. Conversely, when EXP / IH is above the upper limit of condition (8), the angle of incidence of light tends to be low, but it tends to be difficult to shorten the overall length of the optical system and miniaturize it. For this reason, the imaging lens 100 can be miniaturized by satisfying condition (8).

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

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

[0055] If condition (9) is below the lower limit, the overall length tends to decrease further, or EfD1 tends to increase, which is undesirable because it worsens various aberrations. Also, if condition (9) is above the upper limit, the overall length tends to increase, which improves optical performance but hinders miniaturization, which is undesirable. Therefore, satisfying condition (9) allows for both high performance and miniaturization.

[0056] Furthermore, the imaging lens 100 of each embodiment satisfies 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 the condition for optimizing the optical length and image height.

[0058] If condition (10) is below the lower limit, the overall length tends to become even smaller, or the Ef image height tends to increase, which worsens aberrations and is therefore undesirable. Also, if condition (10) is above the upper limit, the overall length tends to increase, which improves optical performance but makes miniaturization difficult and is therefore undesirable. Thus, satisfying condition (10) allows for both high performance and miniaturization. Furthermore, the maximum effective image circle (hereinafter referred to as MIC (Maximum Image Circle)) of the optical system is required to ensure that the image formed through the imaging lens 100 is maintained even if the image sensor and the imaging lens 100 are shifted by 0.1 mm in the shift direction during the manufacturing of the imaging lens 100. In other words, by satisfying condition (10), the imaging lens 100 can achieve both high performance and miniaturization.

[0059] Furthermore, in each embodiment, the imaging lens 100 satisfies condition (11) when the refractive index of the material of the first lens L1 with respect to the d line is N1 and the refractive index of the material of the fifth lens L5 with respect 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 in order to fully exhibit the retrofocus function described above, its negative refractive power must be large. In this 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 can be achieved with good chromatic aberration.

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

[0062] If the refractive index N1 is below the lower limit of condition (12), the optical performance will be further improved, but this is undesirable because it will increase the cost. Also, if the refractive index N1 is above the upper limit of condition (12), the optical performance will be affected by chromatic aberration, which is undesirable. Therefore, by satisfying condition (12), the imaging lens 100 can achieve a balance between cost and chromatic aberration, resulting in a bright, high-performance, and compact imaging lens 100.

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

[0064] If the refractive index N5 is below the lower limit of condition (5), or above the upper limit of condition (13), the balance of chromatic aberration is disrupted. Considering the balance between cost and chromatic aberration, satisfying 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 condition (14) when the total optical length is TTL. TTL < 3.0mm··· (14)

[0066] If condition (14) is not satisfied, it becomes difficult to incorporate the imaging lens into the bezel of a monitor such as a laptop computer, so 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 in a laptop computer, it cannot be housed in the space of the thickness portion of the bezel or in the space that houses the display panel, causing the imaging lens 100 to protrude from the surface of the bezel, or increasing the thickness of the bezel or the display panel. As a result, if condition (14) is not satisfied, when the imaging lens 100 is placed in the bezel or display panel, the thickness of the display panel or bezel increases, impairing portability and aesthetics.

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

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

[0069] The information processing device 30 shown in Figures 13 to 15 comprises 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] The imaging device 31 generates an imaging signal by imaging a predetermined field of view under the control of the control unit 34, and outputs this imaging signal to the signal processing unit 32. As shown in Figure 14, the imaging device 31 comprises at least a cover 311, an imaging lens 100 of each embodiment, and a solid image sensor 312. The imaging device 31 is positioned on the front side of the information processing device 30. Specifically, the imaging device 31 is positioned so as to be able to image the user of the information processing device 30. Of course, the position of the imaging device 31 can be appropriately changed depending on the shape, size, and usage of the information processing device 30.

[0071] The cover 311 is constructed using a cover glass or the like, which is a component for protecting the imaging lens 100 from dirt and dust. The information processing device 30 may also be provided with a lid or the like that opens and closes in response to user operation on the cover 311.

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

[0073] The signal processing unit 32, under the control of the control unit 34, performs A / D conversion and other processing on the imaging signal input from the solid image sensor 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).

[0074] The image processing unit 33, under the control of the control unit 34, performs predetermined image processing on the digital imaging signal input from the signal processing unit 32 and outputs it 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). Here, predetermined image processing includes electrical correction processing of shading, white balance adjustment processing, cropping processing of the central part of the image, and noise reduction processing.

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

[0076] The display unit 35 displays, under the control of the control unit 34, video footage being 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, all processed by the image processing unit 33. The display unit 35 also includes a display panel 351 for displaying images and a bezel portion 352 provided around the display panel. The imaging device 31 is positioned in the bezel portion 352. Specifically, the imaging device 31 is positioned with the object side facing the bezel portion 352 on the side facing the user when the information processing device 30 is in use. The thickness of the bezel portion 352 is approximately 5.0 mm, and the imaging lens is required to have a thickness that takes this into account, but the imaging lens of the present invention can be applied to that 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 constructed using flash memory, SSD (Solid State Drive), HDD (Hard Disk Drive), and memory cards, etc.

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

[0079] The input unit 38 receives user input 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, keyboard, mouse, etc.

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

[0081] The information processing device 30 configured in this way can communicate with external devices via Web communication over a network in high-definition 4K using an imaging device 31 having an imaging lens 100.

[0082] In this embodiment, a PC was used as an example of the information processing device 30, but the imaging device 31 can be applied to, for example, a tablet terminal, a mobile phone, or other imaging device. Of course, the imaging device 31 may also be applied to a webcam or the like that can communicate with a PC via wired or wireless connection.

[0083] According to the embodiments described above, it is possible to achieve a compact, wide-angle, bright, and high-performance device.

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

[0085] Furthermore, according to this embodiment, the imaging lens 100 can be made to have a wide angle of view, a small F-number, high performance, and a compact size, so that when shooting video, it can handle shooting in various environments such as dark environments and can also handle high-speed shooting.

[0086] Furthermore, according to this embodiment, a wide-angle field of view, brightness, high performance, and compact size can be realized, thereby improving the matching between the incident angle at the photodetector of the solid-state image sensor and the light rays incident on the photodetector surface.

[0087] Furthermore, according to this embodiment, it is possible to construct a compact, bright, and high-performance lens with approximately 55° half-angle of view using five elements. Therefore, it can be used as a fixed-focus lens for mobile phones such as smartphones or PCs. When high-resolution video recording of 4K or higher (3840 x 2160 or higher) is required, it is possible to correct aberrations sufficiently compared to conventional imaging lenses and meet the required performance.

[0088] Furthermore, according to this embodiment, a compact, bright, and high-performance half-angle lens with a half-angle of approximately 55° can be constructed using five elements. This allows for a shorter overall length in the optical axis direction of the imaging lens 100, as well as a smaller lens diameter, resulting in miniaturization. Consequently, the refractive power of the miniaturized lens is reduced, and the effects of manufacturing and assembly errors are minimized. As a result, productivity can be improved, and production costs can be reduced.

[0089] Furthermore, according to the embodiment, when the imaging device 31 is placed in the bezel portion 352 of the display panel 351 of a laptop or the like, it can be housed within the space of the thickness portion of the bezel portion 352, enabling the realization of a wide-angle, bright, high-performance, and compact device. In the embodiment, the imaging device 31 was provided in the bezel portion 352, but even if it is provided in the internal space of the display panel 351, like 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 and the display panel 351 may increase.

[0090] Furthermore, various inventions can be formed by appropriately combining the multiple components disclosed in the information processing apparatus according to the embodiments of this disclosure. For example, some components may be deleted from all the components described in the information processing apparatus according to the embodiments of this disclosure described above. In addition, the components described in the information processing apparatus according to the embodiments of this disclosure described above may be appropriately combined.

[0091] Furthermore, in the information processing apparatus according to the embodiments of this disclosure, the "parts" described above can be replaced with "means" or "circuits," etc. For example, the control unit can be replaced with control means or control circuit.

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

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

[0094] Examples 1 to 6 of the imaging lens 100 corresponding to each of embodiments 1 to 6 are shown below. The meaning of the symbols in each example is as follows: f: Focal length of the entire lens system fl: Focal length of each lens FNo.: Numerical Number (F-number) R: Radius of curvature of the surface D: Surface spacing Nd: Refractive index for d line Vd: Abbe number for the d line SD: Effective Radius An aspherical surface is expressed by the well-known equation (20), where X is the depth in the optical axis direction, H is the height from the optical axis, R is the radius of paraxial curvature, k is the cone constant, and CN (N= an even number greater than or equal to 4) is the higher-order aspherical coefficient. X=(H 2 / R) / [1+{1-k(H / r) 2} 1 / 2 ] +Σ N=4:even CNH N ...(20) Here N≧4:even This represents the sum of all even numbers where N is 4 or greater.

[0095] [Example 1] f=1.7mm, FNo.=2.1, ω=55° The data for Example 1 is shown in Table 1.

[0096] [Table 1]

[0097] The data for aspherical surfaces is shown below. [Table 2] In the above notation for aspherical surfaces, for example, "6.7853.E-01" means "6.7853*10-1". The same applies to the other examples below.

[0098] The parameter values ​​for each condition are as follows. Table 3 also includes information on EP (Entrance Pupil Position). [Table 3]

[0099] [Table 4]

[0100] Furthermore, in each embodiment, aspherical elements are used in the first lens L1 to the fourth lens L4, and aberrations are effectively corrected by the aspherical elements.

[0101] Figures 2A to 2C show the aberration diagram, MTF, and distortion grid for the above-described Example 1. As is clear from each figure, the performance is good.

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

[0103] [Table 5]

[0104] The data for aspherical surfaces is shown below. [Table 6]

[0105] [Table 8]

[0106] These aberration diagrams, MTF, and distortion grids are shown in Figures 4A to 4C. As is clear from each figure, the performance is good.

[0107] [Example 3] f=1.7mm, FNo.=2.2, ω=56° The data for Example 3 is shown in Table 9.

[0108] [Table 9]

[0109] The data for aspherical surfaces is shown below. [Table 10]

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

[0111] [Table 12]

[0112] These aberration diagrams, MTF, and distortion grids are shown in Figures 6A to 6C. As is clear from each figure, the performance is good.

[0113] [Example 4] f=1.6mm, FNo.=2.0, ω=54° The data for Example 4 is shown in Table 13. [Table 13]

[0114] The data for aspherical surfaces is shown below. [Table 14]

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

[0116] [Table 16]

[0117] These aberration diagrams, MTF, and distortion grids are shown in Figures 8A to 8C. As is clear from each aberration diagram, the performance is good.

[0118] [Example 5] f=1.6mm, FNo.=2.2, HFOV=54° The data for Example 4 is shown in Table 17. [Table 17]

[0119] The data for aspherical surfaces is shown below. [Table 18]

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

[0121] [Table 20]

[0122] These aberration diagrams, MTF, and distortion grids are shown in Figures 10A to 10C. As is clear from each aberration diagram, the performance is good.

[0123] [Example 6] f=1.6mm, FNo.=2.2, HFOV=54° The data for Example 6 is shown in Table 21. [Table 21]

[0124] The data for aspherical surfaces is shown below. [Table 22]

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

[0126] [Table 24]

[0127] These aberration diagrams, MTF, and distortion grids are shown in Figures 12A to 12C. As is clear from each aberration diagram, the performance is good.

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

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

[0130] 30 Information Processing Devices 31 Imaging device 100 imaging lens L1 First Lens L2 Second Lens L3 3rd lens L4 4th lens L5 5th lens S Aperture diaphragm CG cover glass

Claims

1. The first to fifth lenses are arranged in order from the object side, An aperture diaphragm is placed between the first lens and the second lens, Composed of, The first lens is, It is a negative meniscus lens, The second lens is, It is a biconvex positive lens, The third lens is, Based on the sign of the radius of curvature on the optical axis, it is a negative lens with a concave surface facing the object. The fourth lens is, It is a positive meniscus lens with a convex shape on the image plane 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 plane side. When the focal length of the entire optical system is f, the total length of the lens is TTL, the air gap between the first lens and the second lens is D1-2, the focal length of the first lens is f1, and the focal length of the entire optical system is f, then conditions (1), (2), (3) 0.50 < f / TTL < 0.60...(1) 5.0e-3 < D1-2 / TTL < 4.0e-2 ... (2) 3.0 < |f1 / f| < 6.0...(3) An imaging lens that satisfies the requirements.

2. The imaging lens according to claim 1, The material of the second lens is, It is glass. Imaging lens.

3. A first lens to a fifth lens arranged in order from the object side, An aperture diaphragm is placed between the first lens and the second lens, Composed of, The first lens is, It is a negative meniscus lens, The second lens is, It is a biconvex positive lens, The third lens is, Based on the sign of the radius of curvature on the optical axis, it is a negative lens with a concave surface facing the object. The fourth lens is, It is a positive meniscus lens with a convex shape on the image plane 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 plane side. When the focal length of the entire optical system is f, the total length of the lens is TTL, the air gap between the first lens and the second lens is D1-2, the focal length of the first lens is f1, and the focal length of the second lens is f2, then conditions (1), (2), (4) 0.50 < f / TTL < 0.60...(1) 5.0e-3 < D1-2 / TTL < 4.0e-2 ... (2) 3.5 < | f1 / f2 | < 4.5 ... (4) An imaging lens that satisfies the requirements.

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, condition (5) 4.5 < | f1 / f5 | < 7.0 ... (5) An imaging lens that satisfies the requirements.

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, condition (6) 0.7 < | f4 / f5 | < 1.2 ... (6) An imaging lens that satisfies the requirements.

6. A first lens to a fifth lens arranged in order from the object side, An aperture diaphragm is placed between the first lens and the second lens, Composed of, The first lens is, It is a negative meniscus lens, The second lens is, It is a biconvex positive lens, The third lens is, Based on the sign of the radius of curvature on the optical axis, it is a negative lens with a concave surface facing the object. The fourth lens is, It is a positive meniscus lens with a convex shape on the image plane 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 plane side. When the focal length of the entire optical system is f, the total length of the lens is TTL, the air gap between the first and second lenses is D1-2, the focal length of the lens group on the object side of the aperture diaphragm is F1, and the focal length of the lens group on the image plane side of the aperture diaphragm is F2, then conditions (1), (2), (7) 0.50 < f / TTL < 0.60...(1) 5.0e-3 < D1-2 / TTL < 4.0e-2 ... (2) 3.5 < |F1 / F2 | < 5.5...(7) An imaging lens that satisfies the requirements.

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, condition (8) 0.75 < |EXP / IH| < 1.0...(8) An imaging lens that satisfies the requirements.

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

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

10. The imaging lens described in claim 1, A solid-state image sensor that receives the 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. An information processing apparatus according to claim 11, The aforementioned display unit is A display panel that displays images, A bezel portion is provided around the aforementioned display panel, Equipped with, The imaging device is The bezel portion is arranged as follows: Information processing device.

Images