Light detection device

Abstract

To suppress lowering of resolution while sensitivity is improved when fine structures are used.SOLUTION: The light detection device includes: a photoelectric conversion region having a plurality of pixels; and a light control region that is laminated on the photoelectric conversion region and controls a propagating direction of light to the photoelectric conversion region. The light control region has a pixel control region having a fine structure for each of the plurality of pixels, and the pixel control region controls the propagating direction of the light in a light amount within an opening range according to an image height.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a light detection device.

Background Art

[0002] Generally, in a light detection device such as an image sensor, the amount of incident light decreases on the peripheral side compared to the central side of the photoelectric conversion region, which is a factor causing a decrease in the sensitivity and S / N ratio of the peripheral portion and deterioration of the image quality. Even when an on-chip lens is arranged on the light incident surface side of the photoelectric conversion region, a decrease in the sensitivity of the peripheral portion occurs.

[0003] When the light transmitted through the on-chip lens forms an image on the light receiving surface of the photoelectric conversion region, the amount of light is the largest and brightest at the optical axis position, and the amount of light decreases and becomes darker as the distance from the optical axis increases. This phenomenon is called a decrease in peripheral light amount, or insufficient peripheral light amount, or peripheral light reduction. The decrease in peripheral light amount occurs according to the vignetting and the cosine fourth power law.

[0004] On the other hand, a technique has been proposed in which a microstructured body is arranged on the light incident surface side of a photodiode instead of an on-chip lens so as to capture light from peripheral pixels (see Patent Document 1). By controlling the shape and the like of the microstructured body, the propagation direction of light can be controlled.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, even when a microstructured body is arranged on the light incident surface side of a photodiode, there is a possibility that the sensitivity decreases on the peripheral side compared to the central side of the photoelectric conversion region. Further, when the propagation direction of light is controlled by the microstructured body, color mixing is likely to occur, and there is a possibility that the sensitivity decreases. Patent Document 1 does not specifically mention measures to prevent a decrease in sensitivity at the periphery of the photoelectric conversion region, nor measures to prevent color mixing caused by the provision of microstructures. Therefore, this disclosure provides a photodetector that can improve sensitivity while suppressing a decrease in resolution when using microstructures. [Means for solving the problem]

[0007] To solve the above problems, according to this disclosure, a photoelectric conversion region having multiple pixels, The photoelectric conversion region is stacked on the photoelectric conversion region and comprises an optical control region that controls the direction of light propagation to the photoelectric conversion region, The light control region has a pixel control region having a microstructure for each of the plurality of pixels, The aforementioned pixel control region is provided with a light detection device that controls the propagation direction of light within the aperture range corresponding to the image height.

[0008] The plurality of pixel control regions corresponding to the plurality of pixels may control the aperture range by varying at least one of the following according to the image height: the pitch diameter of the microstructure, the pitch spacing between the microstructures, the gap spacing between the microstructures, and the number of pitches of the microstructures.

[0009] The pixel control region may be configured such that the aperture range is larger as the image height increases, and smaller as the image height decreases.

[0010] According to this disclosure, a photoelectric conversion region having multiple pixels, The system comprises an optical control region positioned on the side of the photoelectric conversion region that is incident on the side of the photoelectric conversion region, and which controls the direction of light propagation to the photoelectric conversion region, The light control region has a pixel control region having a microstructure for each of the plurality of pixels, A light detection device is provided that controls the aperture range corresponding to the amount of light incident on the corresponding pixel control region by making at least one of the following different depending on the image height: the pitch diameter of the microstructure, the pitch spacing between the microstructures, the gap spacing between the microstructures, and the number of pitches of the microstructures.

[0011] The pixel control region may propagate more light to the photoelectric conversion region as the image height increases, and less light to the photoelectric conversion region as the image height decreases.

[0012] The photoelectric conversion region has multiple color pixels for each of the multiple pixels, The light control region has a pixel control region for each of the plurality of color pixels, The pixel control region may control the direction of light propagation according to the wavelength of the incident light and the image height.

[0013] The aforementioned pixel control region may vary the rate of change of the amount of incident light in response to a change in image height depending on the wavelength of the incident light.

[0014] Each of the multiple pixel control regions corresponding to the multiple color pixels contained in a single pixel may control the aperture range based on the difference in the number of color pixels of each color within the single pixel.

[0015] The pixel control region corresponding to a color pixel with a small number of color pixels within that single pixel may have a larger aperture range to transmit more light.

[0016] The optical control region and the photoelectric conversion region are interposed to include a color filter region corresponding to the plurality of color pixels, The aforementioned color filter region has multiple color filter sections for each pixel, The pixel control region may control the aperture range based on the difference in the number of each color of the plurality of color filter sections.

[0017] The plurality of pixel control regions corresponding to the plurality of pixels may have different materials of the microstructures according to the image height.

[0018] The microstructures include a plurality of columnar members that are spaced apart from each other along the light incident surface, and a base member that covers the periphery of the plurality of columnar members. The plurality of pixel control regions corresponding to the plurality of pixels may have different materials of at least one of the columnar members and the base member according to the image height.

[0019] Among the plurality of pixel control regions corresponding to the plurality of pixels, pupil correction may be performed in at least some of the pixel control regions for incident light.

[0020] The pupil correction amount may be increased for the pixel control regions located more on the peripheral side than the central side of the light control region.

[0021] Pupil correction is performed by shifting the pixel control region within the light control region along the light incident surface with respect to the corresponding pixel within the photoelectric conversion region, and the amount of shifting the pixel control region within the light control region with respect to the corresponding pixel within the photoelectric conversion region may be increased for the pixel control regions located more on the peripheral side than the central side of the light control region.

[0022] Pupil correction is performed by shifting the pixel control region within the light control region along the light incident surface with respect to the corresponding color filter portion within the color filter region, and the amount of shifting the pixel control region within the light control region with respect to the corresponding color filter portion within the color filter region may be increased for the pixel control regions located more on the peripheral side than the central side of the light control region.

[0023] The light control region includes a first light control portion having a first microstructure, The first optical control unit is stacked with the second optical control unit having a second microstructure, The first optical control unit and the second optical control unit each have a pixel control region having a microstructure for each of the plurality of pixels, Pupil correction is performed by shifting the pixel control region in the first light control unit along the light incident surface relative to the corresponding pixel control region in the second light control unit. The further a pixel control region is located from the center of the optical control region to the periphery, the greater the amount by which the pixel control region in the first optical control unit is shifted relative to the corresponding pixel control region in the second optical control unit. [Brief explanation of the drawing]

[0024] [Figure 1] A block diagram showing a schematic configuration of a photodetector according to one embodiment of the present disclosure. [Figure 2] A diagram illustrating the principles of microstructures. [Figure 3A] This diagram shows the direction of light incidence into the photoelectric conversion region when a lens is placed on the light incidence side of the photoelectric conversion region. [Figure 3B] This diagram shows the direction of light incidence into the photoelectric conversion region when an optical control region is provided between the lens and the photoelectric conversion region. [Figure 4] A diagram showing the relationship between image height and brightness. [Figure 5] A schematic cross-sectional view of the light detection device 1 according to this embodiment. [Figure 6] A diagram illustrating a color splitter. [Figure 7A] A schematic plan view illustrating how each pixel control region corresponding to each color pixel within a color splitter takes in light from the surroundings. [Figure 7B] This figure follows Figure 7A. [Figure 7C] This figure follows Figure 7B. [Figure 8A] A diagram showing the relationship between the aperture and sensitivity of a color splitter. [Figure 8B] A diagram showing the relationship between the aperture and resolution of a color splitter. [Figure 9]A schematic plan view showing the aperture range for red and blue pixels. [Figure 10] Figure 9 shows circles indicating the opening range arranged along the radial direction. [Figure 11] A diagram showing the aperture range in the cross-sectional direction of the light detection device from the center to the periphery of the color splitter. [Figure 12] A schematic plan view showing the aperture range for the green pixels. [Figure 13] Figure 12 shows circles indicating the opening range arranged radially. [Figure 14] A diagram showing the aperture range 16 in the cross-sectional direction of the light detection device from the center to the periphery of the color splitter. [Figure 15] A diagram that explains pupil correction in more detail. [Figure 16] A diagram showing an example of pupil correction when a light-shielding wall is installed. [Figure 17] Plan and cross-sectional views of the microstructure within the color splitter. [Figure 18A] A plan view illustrating the pitch diameter, pitch spacing, and gap spacing of the pillar section. [Figure 18B] A cross-sectional diagram illustrating the pillar height. [Figure 19A] A plan view showing the first example of microstructures within a color splitter. [Figure 19B] A plan view showing a second example of the microstructure within a color splitter. [Figure 19C] A plan view showing a third example of microstructures within a color splitter. [Figure 20] A block diagram showing an example of a general configuration of a vehicle control system. [Figure 21] An explanatory diagram showing an example of the installation location of the external information detection unit and the imaging unit. [Modes for carrying out the invention]

[0025] The embodiments of the photodetector will be described below with reference to the drawings. While the main components of the photodetector will be described below, there may be components and functions not shown or described in the drawings. The following description does not exclude any components or functions not shown or described.

[0026] (Outline configuration of the imaging device) Figure 1 is a block diagram showing the schematic configuration of a photodetector 1 according to one embodiment of the present disclosure. The photodetector 1 in Figure 1 shows the schematic configuration of an image sensor, i.e., an imaging device. The photodetector 1 according to this embodiment is also applicable to devices equipped with photodetection functions other than image sensors, such as devices equipped with ToF (Time of Flight) functions or photon counting functions.

[0027] The photodetector 1 in Figure 1 comprises a pixel array section 2, a vertical drive circuit 3, a column signal processing circuit 4, a horizontal drive circuit 5, an output circuit 6, and a control circuit 7.

[0028] The pixel array section 2 has a plurality of pixels 10 arranged in the row and column directions, a plurality of signal lines L1 extending in the column direction, and a plurality of row selection lines L2 extending in the row direction. Although not shown in Figure 1, each pixel 10 has a photoelectric conversion unit and a readout circuit that reads out a pixel signal corresponding to the photoelectrically converted charge onto the signal line L1. The pixel array section 2 is a laminate formed by stacking a photoelectric conversion region in which the photoelectric conversion units are arranged in a two-dimensional direction and a readout circuit region in which the readout circuits are arranged in a two-dimensional direction.

[0029] The vertical drive circuit 3 drives multiple row selection lines L2. Specifically, the vertical drive circuit 3 supplies drive signals to the multiple row selection lines L2 in line sequence, and selects each row selection line L2 in line sequence.

[0030] Multiple signal lines L1 extending in the column direction are connected to the column signal processing circuit 4. The column signal processing circuit 4 performs analog-to-digital (AD) conversion of multiple pixel signals supplied via the multiple signal lines L1. More specifically, the column signal processing circuit 4 compares the pixel signals on each signal line L1 with a reference signal and generates a digital pixel signal based on the time it takes for the signal levels of the pixel signal and the reference signal to match. The column signal processing circuit 4 sequentially generates a digital pixel signal (P-phase signal) at the reset level of the floating diffusion layer within the pixel and a digital pixel signal (D-phase signal) at the pixel signal level, and performs correlated double sampling (CDS).

[0031] The horizontal drive circuit 5 controls the timing of transferring the output signal from the column signal processing circuit 4 to the output circuit 6.

[0032] The control circuit 7 controls the vertical drive circuit 3, the column signal processing circuit 4, and the horizontal drive circuit 5. The control circuit 7 generates a reference signal that the column signal processing circuit 4 uses to perform AD conversion.

[0033] The photodetector 1 in Figure 1 can be constructed by stacking a first substrate on which a pixel array section 2 and the like are arranged, and a second substrate on which a vertical drive circuit 3, a column signal processing circuit 4, a horizontal drive circuit 5, an output circuit 6, and a control circuit 7 and the like are arranged, using Cu-Cu connections, bumps, or vias.

[0034] The photodiode PD of each pixel in the pixel array 2 is located in the photoelectric conversion region. Although not shown in Figure 1, the imaging device according to this embodiment includes an optical control region stacked on the photoelectric conversion region. As will be described later, the optical control region uses a microstructure to transform the optical properties of the incident light. For example, the optical control region can improve the quantum efficiency Qe in the photoelectric conversion region by increasing the optical path length of the incident light.

[0035] Figure 2 illustrates the principle of the microstructure 14. Figure 2 shows an example where regions A and B, which transmit light, are adjacent to each other. Regions A and B have a length L in the direction of light propagation. The refractive index of region B is n0. In contrast, a portion of region A (L-L1) has a refractive index of n0, and the remaining L1 has a refractive index of n1.

[0036] The optical path length dA in region A and the optical path length dB in region B in Figure 2 are expressed by the following equations (1) and (2). dA = n0 × (L - L1) + n1 × L1 …(1) dB = n0 × L

[0037] Therefore, the difference in optical path length Δd between region A and region B is expressed by the following equation (3). Δd = dB - dA = L1(n0 - n1) …(3)

[0038] Furthermore, the phase difference φ between region A and region B is expressed by the following equation (4). φ = 2πL1(n0-n1) / λ …(4)

[0039] As shown in equation (4), the optical path length of light propagating between region A and region B changes according to the refractive index difference between region A and region B, and a difference in the direction of propagation occurs according to the refractive index difference. The difference in the direction of propagation depends on the wavelength of the light.

[0040] In this way, by irradiating the microstructure 14 with light, the optical path length and propagation direction of the light can be changed. Furthermore, as will be described later, the optical path length and propagation direction of the light can be varied in various ways by adjusting the width or shape, orientation, number, etc., of the microstructure 14.

[0041] Figure 3A shows the direction of light incidence into the photoelectric conversion region 11 when the lens 12 is placed on the light incidence surface side of the photoelectric conversion region 11. Figure 3B shows the direction of light incidence into the photoelectric conversion region 11 when a light control region 13 is provided between the lens 12 and the photoelectric conversion region 11. Figure 4 shows the relationship between image height and brightness in Figures 3A and 3B. The horizontal axis of Figure 4 is image height [%], and the vertical axis is relative brightness [%]. Here, image height is the radial distance from the optical axis center position of the lens 12 to the subject light incidence position. Curve w1 in Figure 4 shows the change in brightness with respect to image height in Figure 3A, and curve w2 shows the change in brightness with respect to image height in Figure 3B.

[0042] As shown in Figures 3A and 3B, the proportion of oblique light incident on the peripheral side of the lens 12 is greater than on the central side of the lens 12, i.e., the side closer to the optical axis. Therefore, as shown by curve w1 in Figure 4, the amount of light incident on the photoelectric conversion region 11 is less on the peripheral side than on the central side. However, by providing an optical control region 13 having a microstructure 14 between the lens 12 and the photoelectric conversion region 11, as shown in Figure 3B, light from peripheral pixels can be captured, as shown by curve w2 in Figure 4. As a result, the amount of light on the peripheral side, where the image height is greater, can be increased compared to the case in Figure 3A, and the brightness can be improved.

[0043] Figure 5 is a schematic cross-sectional view of the photodetector 1 according to this embodiment. The photodetector 1 according to this embodiment has a structure in which a photoelectric conversion region 11, a color filter region 15, and a light control region 13 are stacked.

[0044] The photoelectric conversion region 11 has multiple pixels 10, each of which performs photoelectric conversion. Each pixel 10 is composed of multiple color pixels 10c (10r, 10g, 10b). The photoelectric conversion region 11 has a photodiode for each color pixel 10c. In the case of a Bayer array, each pixel 10 is composed of a total of four color pixels 10c, two in the vertical and two in the horizontal.

[0045] The color filter region 15 has a color filter section that transmits light of a wavelength corresponding to each color pixel 10c. Since one pixel 10 is composed of multiple color pixels 10c, the color filter region 15 has multiple color filter sections for each pixel 10. The color filter section mainly transmits light of the wavelength band corresponding to the color.

[0046] The light control region 13 is located on the side of the light incidence direction than the color filter region 15. The light control region 13 has a pixel control region 17 having a microstructure 14 for each of the multiple pixels 10. In this specification, the light control region 13 may be referred to as the color splitter 13. The pixel control region 17 transmits light within an aperture range 16 (see Figure 6, described later) corresponding to the image height. As described later, the multiple pixel control regions 17 corresponding to the multiple pixels 10 control the aperture range 16 by varying at least one of the following according to the image height: the pitch diameter of the microstructure 14, the pitch spacing between the microstructures 14, the gap spacing between the microstructures, and the number of pitches of the microstructures 14.

[0047] A light-transmitting insulating layer 20 is placed between the light control region 13 and the color filter region 15. Additionally, an anti-reflective film or protective film (not shown) may be placed on the light incident surface side of the light control region 13.

[0048] The pixel control region 17 increases the aperture range 16 as the image height increases, and decreases the aperture range 16 as the image height decreases.

[0049] The photoelectric conversion region 11 has multiple color pixels 10c for each of the multiple pixels 10. The color splitter 13 has a pixel control region 17 for each of the multiple color pixels 10c. The pixel control region 17 transmits light of an amount corresponding to the wavelength and image height of the incident light.

[0050] The pixel control region 17 differentiates the rate of change of the amount of incident light in response to a change in image height depending on the wavelength of the incident light. Each of the multiple pixel control regions 17 corresponding to multiple color pixels 10c contained in a single pixel 10 controls the aperture range 16 based on the difference in the number of color pixels 10c of each color within the single pixel 10. The pixel control region 17 corresponding to a single pixel 10 with fewer color pixels 10c of each color may have a larger aperture range 16 to transmit more light.

[0051] Figure 6 illustrates the color splitter 13 described above. More specifically, Figure 6 illustrates the function of the color splitter 13 when the color pixels 10c are arranged in a Bayer array in the photoelectric conversion region 11. In a Bayer array, one pixel 10 consists of four color pixels 10c. The four color pixels 10c include one red pixel 10r, two green pixels 10g, and one blue pixel 10b.

[0052] Figure 6A is a plan view of the four color pixels 10c that constitute the Bayer array. Figure 6B is a cross-sectional view in the direction of line AA of Figure 6A, and Figure 6C is a cross-sectional view in the direction of line BB of Figure 6A. The color splitter 13 is provided with a plurality of columnar microstructures 14, and the aperture range 16 that captures light differs for each wavelength of light. In this specification, the individual columnar members that constitute each microstructure 14 are called pillar sections 14p. The pillar sections 14p may be cylindrical or cubic in shape. In addition, the individual microstructures 14 may have a shape in which the width in the height direction changes.

[0053] In the AA line direction of Figure 6A, as shown in Figure 6B, light of green wavelength is captured from the aperture range 16 at the base of the arrow shown and received by the green pixel 10g, and light of red wavelength is captured from the aperture range 16 at the base of the arrow shown and received by the red pixel 10r. Similarly, in the BB line direction of Figure 6A, as shown in Figure 6C, light of green wavelength is captured from the aperture range 16 at the base of the arrow shown and received by the green pixel 10g, and light of red wavelength is captured from the aperture range 16 at the base of the arrow shown and received by the red pixel 10r.

[0054] In this way, by providing a color splitter 13 consisting of a microstructure 14, the aperture range 16 for capturing light can be widened, and light incident on the pixel control region 17 corresponding to the adjacent pixel 10 can be captured.

[0055] Figures 7A, 7B, and 7C are schematic plan views illustrating how each pixel control region 17 corresponding to each color pixel 10c in the color splitter 13 captures light from the surroundings. As shown in Figure 7A, the pixel control region 17 corresponding to the red pixel 10r captures light within an aperture range 16 that extends to eight pixel control regions 17 corresponding to the eight surrounding color pixels 10c. There are two pixel control regions 17 corresponding to the green pixel 10g within a single pixel 10, and as shown in Figure 7B, the pixel control region 17 corresponding to each green pixel 10g captures color within an aperture range 16 that includes the four surrounding color pixels 10c. As shown in Figure 7C, the blue pixel 10b captures light within an aperture range 16 that extends to eight pixel control regions 17 corresponding to the eight surrounding color pixels 10c.

[0056] Figure 8A shows the relationship between the aperture and sensitivity of the color splitter 13. Figure 8A shows schematic plan and cross-sectional views of the color splitter 13, as well as the relationship between the amount of light incident on the color splitter 13, the amount of light emitted from the color splitter 13, and the sensitivity, for both a small aperture range 16 (diameter r1) and a large aperture range 16 (diameter r3).

[0057] As shown in Figure 8A, the smaller the aperture range 16 of the color splitter 13, the more light is concentrated in the center of each color pixel 10c, resulting in a smaller improvement in the sensitivity of each color pixel 10c. On the other hand, the larger the aperture range 16 of the color splitter 13, the more light can be increased at the periphery of each color pixel 10c, resulting in a larger improvement in the sensitivity of each color pixel 10c.

[0058] Figure 8B is a diagram showing the relationship between the aperture and resolution of the color splitter 13. Figure 8B illustrates schematic plan and cross-sectional views of the color splitter 13, the relationship between the subject light image incident on the color splitter 13, the subject light image emitted from the color splitter 13, and the resolution, for both small and large aperture ranges 16.

[0059] As shown in Figure 8B, the smaller the aperture range 16, the less likely color mixing will occur between adjacent color pixels 10c. On the other hand, the larger the aperture range 16, the more likely color mixing will occur between adjacent color pixels 10c.

[0060] Thus, increasing the aperture range 16 of the color splitter 13 improves sensitivity, but makes color mixing more likely. Conversely, decreasing the aperture range 16 reduces sensitivity, but makes color mixing less likely. Therefore, it is desirable to control the aperture range 16 depending on the location within the color splitter 13. More specifically, it is desirable to make the aperture range 16 smaller towards the center of the color splitter 13 and larger towards the periphery.

[0061] Figure 9 is a schematic plan view showing the aperture range 16 for the red pixel 10r and the blue pixel 10b. In Figure 9, the aperture range 16 of the pixel control region 17 corresponding to each color pixel 10c, from the center to the periphery of the color splitter 13, is schematically represented by circles.

[0062] Figure 10 is a diagram showing circles representing the aperture range 16 in Figure 9 arranged radially. As shown in Figure 10, the aperture range 16 gradually widens from the center to the periphery of the color splitter 13. The wider the aperture range 16, the greater the amount of light incident on the corresponding color pixels 10c, and the higher the sensitivity.

[0063] FIG. 11 is a diagram showing an aperture range 16 in the cross-sectional direction of the light detection device 1 from the central portion to the peripheral portion of the color splitter 13. In FIG. 11A, the aperture ranges 16 (diameters r1, r2, r3 (r1 < r2 < r3)) of the pixel control regions 17 corresponding to the three color pixels 10c in FIG. 10 are shown. As shown in FIG. 11A, the wider the aperture range 16, the greater the amount of light incident on the corresponding color pixel 10c, and the higher the sensitivity.

[0064] More light in the diagonal direction is incident on the peripheral portion of the color splitter 13 than on the central portion. The fine structure 14 in the color splitter 13 can change the propagation direction of the light from the diagonal direction, but it cannot be said that only the fine structure 14 is sufficient. Therefore, it is desirable to perform pupil correction to shift the relative positional relationship between the color splitter 13 and the photoelectric conversion region 11.

[0065] FIG. 11B is a schematic cross-sectional view when pupil correction is performed. In FIG. 11B, on the peripheral side of the photoelectric conversion region 11, the position of the photoelectric conversion region 11 is shifted along the direction of the incident light to the color splitter 13. Thereby, even when light is obliquely incident on the color splitter 13, the light can be incident on the corresponding color pixel 10c.

[0066] Note that, as shown in FIG. 11B, the pupil correction amount is smaller on the central side of the photoelectric conversion region 11 (color splitter 13) and larger on the peripheral side.

[0067] Thus, in this embodiment, pupil correction can be performed by shifting the pixel control area 17 within the light control area 13 along the light incident surface relative to the corresponding pixel 10 in the photoelectric conversion area 11. The further a pixel control area 17 is located from the center of the light control area 13 to the periphery, the greater the amount by which the pixel control area 17 within the light control area 13 is shifted relative to the corresponding pixel 10 in the photoelectric conversion area 11. More specifically, pupil correction is performed by shifting the pixel control area 17 within the light control area 13 along the light incident surface relative to the corresponding color filter portion in the color filter area 15. The further a pixel control area 17 is located from the center of the light control area 13 to the periphery, the greater the amount by which the pixel control area 17 within the light control area 13 is shifted relative to the corresponding color filter portion in the color filter area 15.

[0068] Furthermore, as shown in Figure 11B, by making the color splitter 13 a two-layer structure and shifting the relative positional relationship of each layer along the light incident surface, pupil correction can be performed, thereby enhancing the pupil correction effect.

[0069] Figure 12 is a schematic plan view showing the aperture range 16 for the green pixel 10g. Figure 13 is a diagram showing circles representing the aperture range 16 in Figure 12 arranged radially. Figure 14 is a diagram showing the aperture range 16 in the cross-sectional direction of the light detection device 1 from the center to the periphery of the color splitter 13.

[0070] In the case of a Bayer array, there are two green pixels 10g within a single pixel 10, and they have a greater light intensity compared to the other color pixels 10r and 10b. Therefore, the aperture range 16 of the green pixels 10g can be made smaller than that of the red pixels 10r and blue pixels 10b. Accordingly, in Figures 12 and 13, the size of the circle indicating the aperture range 16 is smaller than the size of the circle in Figures 10 and 11. However, the aperture range 16 gradually widens from the center to the periphery of the color splitter 13, similar to the red pixels 10r and blue pixels 10b.

[0071] Furthermore, even with 10g of green pixels, more light is incident at an oblique angle to the periphery of the color splitter 13 than to the center, so pupil correction is desirable. Figure 14A is a cross-sectional view without pupil correction, and Figure 14B is a cross-sectional view with pupil correction. In Figure 14B, the amount of pupil correction is gradually increased from the center to the periphery of the color splitter 13.

[0072] Figures 11 and 14 illustrate an example in which pupil correction (hereinafter referred to as first pupil correction) is performed by shifting the relative positional relationship between the color splitter 13 and the color filter region 15 (photoelectric conversion region 11) along the light incident plane, and pupil correction (hereinafter referred to as second pupil correction) is performed by making the color splitter 13 into two layers and shifting the relative positional relationship of each layer along the light incident plane. However, it is also possible to perform only one of the first or second pupil correction.

[0073] Figure 15 is a diagram that explains pupil correction in more detail. Figure 15 illustrates pupil correction when light is incident on the central part of the color splitter 13, when light is incident on the area midway between the central and peripheral parts of the color splitter 13, and when light is incident on the peripheral part of the color splitter 13.

[0074] Figure 15A is a schematic plan view showing the incident light positions bs on the color splitter 13. Figure 15B is a schematic cross-sectional view of the light detection device 1 when pupil correction is not performed at the three incident positions bs shown in Figure 15A. Figure 15C is a schematic cross-sectional view of the light detection device 1 when pupil correction is performed in the first example at the three incident positions bs shown in Figure 15A. Figure 15D is a schematic cross-sectional view of the light detection device 1 when pupil correction is performed in the second example at the three incident positions bs shown in Figure 15A.

[0075] In the central part of the color splitter 13, a large proportion of light is incident from the direction normal to the light incident surface, so pupil correction is not necessary. Therefore, the cross-sectional structures in Figures 15B to 15D are almost the same.

[0076] Near the midpoint between the center and periphery of the color splitter 13, the proportion of light coming from an oblique direction increases, making pupil correction desirable. Therefore, in Figure 15C, the color splitter 13 is made into a two-layer structure, and pupil correction is performed by shifting the relative positional relationship of these two layers along the light incidence plane.

[0077] More specifically, the color splitter 13 in Figures 11B, 14B, 15C, and 15D has a stacked first light control unit 13a and a second light control unit 13b. The first light control unit 13a and the second light control unit 13b each have a microstructure 14. In this specification, the microstructure of the first light control unit 13a may be referred to as the first microstructure 14a, and the microstructure of the second light control unit 13b may be referred to as the second microstructure 14b. Pupil correction can be performed by shifting the relative positional relationship between the first light control unit 13a and the second light control unit 13b along the light incident plane.

[0078] In Figure 15D, in addition to the pupil correction shown in Figure 15C, the relative positional relationship between the color splitter 13 and the photoelectric conversion region 11 is shifted along the light incident plane. This allows for a greater amount of pupil correction than in Figure 15C.

[0079] If the color splitter 13 has a single-layer structure, pupil correction cannot be performed by the color splitter 13 alone. Therefore, as shown in Figure 15D, pupil correction is performed by shifting the relative positional relationship between the color splitter 13 and the color filter region 15 (photoelectric conversion region 11).

[0080] At the periphery of the color splitter 13, the proportion of light coming from oblique directions increases further, thus increasing the need for pupil correction. Therefore, in Figure 15C, pupil correction is performed by shifting the relative positions of the first light control unit 13a and the second light control unit 13b within the color splitter 13 more significantly. Furthermore, in Figure 15D, in addition to the pupil correction in Figure 15C, pupil correction is performed by shifting the relative positions of the color splitter 13 and the color filter region 15 (photoelectric conversion region 11) more significantly.

[0081] The color splitter 13 may have a light-shielding wall 18 (first light-shielding wall) at the boundary of the pixel control region 17 corresponding to the color pixel 10c. Similarly, the color splitter 13 provided in the photoelectric conversion region 11 may have a light-shielding wall 19 (second light-shielding wall) at the boundary of the color pixel 10c. By providing these light-shielding walls 18 and 19, it is possible to prevent the incidence of light from the region of the adjacent color pixel 10c.

[0082] Figure 16 shows an example of pupil correction when the light-shielding walls 18 and 19 described above are provided. Figure 16 shows the cross-sectional structure of the light detection device 1 in the central, intermediate, and peripheral parts of the color splitter 13. In the central part of the color splitter 13, the relative positions of the light-shielding wall 18 inside the color splitter 13 and the light-shielding wall 19 inside the color filter region 15 are aligned in the stacking direction, but in the intermediate part, the relative positions of these light-shielding walls 18 and 19 are slightly misaligned along the light incidence surface. In the peripheral part, the relative positions of these light-shielding walls 18 and 19 are more significantly misaligned.

[0083] Figure 17 shows a plan view and a cross-sectional view of the microstructure 14 within the color splitter 13. The color splitter 13 is divided into pixel control regions 17 corresponding to individual color pixels 10c, and each pixel control region 17 has a microstructure 14. Each microstructure 14 has a plurality of pillar portions 14p that extend in the stacking direction. The plurality of pillar portions 14p are surrounded by a base member 14b. The refractive index of the pillar portions 14p is greater than that of the base member 14b. The material of the pillar portions 14p is an insulating material such as TiO2. More specifically, the pillar portions 14p are composed of silicon compounds such as silicon nitride and silicon carbide, metal oxides such as titanium oxide, tantalum oxide, niobium oxide, hafnium oxide, indium oxide, and tin oxide, or composite oxides thereof. In addition, the pillar portions 14p may be composed of organic materials such as siloxane. The material of the base member is an insulating material such as SiO2.

[0084] The color splitter 13 controls the aperture range 16 through which light is transmitted by varying at least one of the following for each pixel control region 17 corresponding to a color pixel 10c, according to the image height: the pitch diameter of the pillar portion 14p, the pitch spacing between pillar portions 14p, the gap spacing between pillar portions 14p, and the number of pillar portions 14p. The color splitter 13 can also control the aperture range 16 for each pixel control region 17 corresponding to a color pixel 10c by controlling at least one of the following: the material of the pillar portion 14p and the material of the base member 14b, the shape of the pillar portion 14p, the number of pillar portions 14p, and the length of the pillar portion 14p in the stacking direction, according to the image height.

[0085] Figure 18A is a plan view illustrating the pitch diameter, pitch spacing, and gap spacing of the pillar section 14p, and Figure 18B is a cross-sectional view illustrating the pillar height. As shown in Figure 18A, the pitch diameter is the diameter of the cylinder if the pillar section 14p is cylindrical. The pitch spacing is the shortest distance between the center positions of two adjacent pillar sections 14p. The gap spacing is the shortest distance between the outer surfaces of two adjacent pillar sections 14p. As shown in Figure 18B, the pillar height is the length of the pillar section 14p in the stacking direction.

[0086] In the example shown in Figure 17, the structures of the microstructures 14 of the red pixel 10r and the blue pixel 10b are identical, and the structures of the microstructures 14 of the two blue pixels 10b within the Bayer array are also identical. Furthermore, in the example shown in Figure 17, the diameter of the pillar portion 14p of the green pixel 10g and the blue pixel 10b is smaller than the diameter of the pillar portion 14p of the green pixel 10g. In addition, in the example shown in Figure 17, multiple pillar portions 14p are arranged along the boundary of the pixel control region 17.

[0087] Figure 17 shows an example of the microstructure 14, and various modifications are possible for the arrangement of the pillar portion 14p. Figure 19A is a plan view showing the first example of the microstructure 14 in the color splitter 13. Figure 19B is a plan view showing the second example of the microstructure 14 in the color splitter 13. Figure 19C is a plan view showing the third example of the microstructure 14 in the color splitter 13.

[0088] In Figures 19A, 19B, and 19C, the structure of the microstructure 14 within the pixel control region 17 corresponding to the red pixel 10r and the green pixel 10g is identical. Furthermore, the structure of the microstructure 14 within the pixel control region 17 corresponding to the two green pixels 10g in the Bayer array is also identical. Figures 19A to 19C are examples of the microstructure 14, and various modifications are conceivable.

[0089] Thus, in this embodiment, a pixel control region 17 having a microstructure 14 is provided for each pixel 10 (color pixel 10c) within the color splitter 13, which is positioned on the light incidence side of the photoelectric conversion region 11, so that each pixel control region 17 transmits light within an aperture range 16 corresponding to the image height. As a result, the aperture range 16 on the peripheral side of the color splitter 13 can be made larger than that on the central side, the drop in peripheral light intensity can be suppressed, and sensitivity can be improved.

[0090] Furthermore, the aperture range 16 can be reduced in the central part of the color splitter 13, making the decrease in resolution less noticeable. Therefore, according to this embodiment, it is possible to achieve both improved sensitivity and prevention of a decrease in resolution.

[0091] Furthermore, in this embodiment, the pupil correction amount can be increased as you move from the center of the color splitter 13 towards the periphery, enabling proper pupil correction across the entire photoelectric conversion region 11.

[0092] <<Application Examples>> The technology disclosed herein can be applied to a variety of products. For example, the technology disclosed herein may be implemented as a device mounted on any type of mobile vehicle, such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility devices, airplanes, drones, ships, robots, construction machinery, or agricultural machinery (tractors).

[0093] Figure 20 is a block diagram showing a schematic configuration example of a vehicle control system 7000, which is an example of a mobile control system to which the technology described herein can be applied. The vehicle control system 7000 comprises a plurality of electronic control units connected via a communication network 7010. In the example shown in Figure 20, the vehicle control system 7000 comprises a drive system control unit 7100, a body system control unit 7200, a battery control unit 7300, an external information detection unit 7400, an internal information detection unit 7500, and an integrated control unit 7600. The communication network 7010 connecting these plurality of control units may be an in-vehicle communication network conforming to any standard such as CAN (Controller Area Network), LIN (Local Interconnect Network), LAN (Local Area Network), or FlexRay®.

[0094] Each control unit comprises a microcomputer that performs calculations according to various programs, a storage unit that stores programs executed by the microcomputer or parameters used in various calculations, and a drive circuit that drives various controlled devices. Each control unit is equipped with a network interface for communication with other control units via the communication network 7010, and a communication interface for communication with devices or sensors inside or outside the vehicle via wired or wireless communication. Figure 20 illustrates the functional configuration of the integrated control unit 7600, which includes a microcomputer 7610, a general-purpose communication interface 7620, a dedicated communication interface 7630, a positioning unit 7640, a beacon receiver 7650, an in-vehicle equipment interface 7660, an audio / image output unit 7670, an in-vehicle network interface 7680, and a storage unit 7690. Other control units similarly include a microcomputer, a communication interface, and a storage unit.

[0095] The drivetrain control unit 7100 controls the operation of devices related to the vehicle's drivetrain according to various programs. For example, the drivetrain control unit 7100 functions as a control device for generating driving force for the vehicle, such as an internal combustion engine or a drive motor; a driving force transmission mechanism for transmitting driving force to the wheels; a steering mechanism for adjusting the steering angle of the vehicle; and a braking device for generating braking force for the vehicle. The drivetrain control unit 7100 may also function as a control device such as ABS (Antilock Brake System) or ESC (Electronic Stability Control).

[0096] A vehicle state detection unit 7110 is connected to the drivetrain control unit 7100. The vehicle state detection unit 7110 includes, for example, a gyro sensor for detecting the angular velocity of the vehicle's axial rotational motion, an acceleration sensor for detecting the vehicle's acceleration, or at least one of the sensors for detecting the amount of operation of the accelerator pedal, the amount of operation of the brake pedal, the steering angle of the steering wheel, the engine speed, or the rotational speed of the wheels. The drivetrain control unit 7100 performs calculations using signals input from the vehicle state detection unit 7110 and controls the internal combustion engine, drive motor, electric power steering system, brake system, etc.

[0097] The body system control unit 7200 controls the operation of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 7200 functions as a control device for a keyless entry system, a smart key system, a power window system, or various lamps such as headlights, reverse lights, brake lights, turn signals, or fog lights. In this case, the body system control unit 7200 may receive radio waves transmitted from a portable device that replaces a key or signals from various switches. The body system control unit 7200 receives these radio waves or signals and controls the vehicle's door lock system, power window system, lamps, etc.

[0098] The battery control unit 7300 controls the secondary battery 7310, which is the power source for the drive motor, according to various programs. For example, the battery control unit 7300 receives information such as battery temperature, battery output voltage, or remaining battery capacity from the battery device equipped with the secondary battery 7310. The battery control unit 7300 uses these signals to perform calculations and controls the temperature of the secondary battery 7310 or the cooling device provided in the battery device.

[0099] The external information detection unit 7400 detects information from outside the vehicle equipped with the vehicle control system 7000. For example, at least one of the imaging unit 7410 and the external information detection unit 7420 is connected to the external information detection unit 7400. The imaging unit 7410 includes at least one of the following: a ToF (Time Of Flight) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. The external information detection unit 7420 includes at least one of the following: an environmental sensor for detecting the current weather or climate, or an ambient information detection sensor for detecting other vehicles, obstacles, or pedestrians around the vehicle equipped with the vehicle control system 7000.

[0100] The environmental sensor may be at least one of the following: a raindrop sensor for detecting rain, a fog sensor for detecting fog, a sunshine sensor for detecting the degree of sunlight, and a snow sensor for detecting snowfall. The ambient information detection sensor may be at least one of the following: an ultrasonic sensor, a radar device, and a LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) device. These imaging unit 7410 and external information detection unit 7420 may be provided as independent sensors or devices, or as a device in which multiple sensors or devices are integrated.

[0101] Here, Figure 21 shows examples of the installation locations of the imaging unit 7410 and the external information detection unit 7420. The imaging units 7910, 7912, 7914, 7916, and 7918 are installed, for example, at least one of the following locations on the vehicle 7900: the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield inside the passenger compartment. The imaging unit 7910 installed on the front nose and the imaging unit 7918 installed on the upper part of the windshield inside the passenger compartment mainly acquire images of the front of the vehicle 7900. The imaging units 7912 and 7914 installed on the side mirrors mainly acquire images of the sides of the vehicle 7900. The imaging unit 7916 installed on the rear bumper or back door mainly acquires images of the rear of the vehicle 7900. The imaging unit 7918 installed on the upper part of the windshield inside the passenger compartment is mainly used for detecting preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, or lanes.

[0102] Figure 21 shows an example of the imaging range of each imaging unit 7910, 7912, 7914, and 7916. Imaging range a shows the imaging range of imaging unit 7910 located on the front nose, imaging ranges b and c show the imaging ranges of imaging units 7912 and 7914 located on the side mirrors, respectively, and imaging range d shows the imaging range of imaging unit 7916 located on the rear bumper or back door. For example, by superimposing the image data captured by imaging units 7910, 7912, 7914, and 7916, an overhead view image of the vehicle 7900 can be obtained.

[0103] The external information detection units 7920, 7922, 7924, 7926, 7928, and 7930, which are installed on the front, rear, sides, corners, and the upper part of the windshield inside the vehicle 7900, may be, for example, ultrasonic sensors or radar devices. The external information detection units 7920, 7926, and 7930, which are installed on the front nose, rear bumper, back door, and the upper part of the windshield inside the vehicle 7900, may be, for example, LIDAR devices. These external information detection units 7920 to 7930 are mainly used to detect preceding vehicles, pedestrians, or obstacles.

[0104] Returning to Figure 20, the explanation continues. The external information detection unit 7400 causes the imaging unit 7410 to capture images of the area outside the vehicle and receives the captured image data. The external information detection unit 7400 also receives detection information from the connected external information detection unit 7420. If the external information detection unit 7420 is an ultrasonic sensor, radar device, or LIDAR device, the external information detection unit 7400 emits ultrasonic waves or electromagnetic waves and receives information on the received reflected waves. Based on the received information, the external information detection unit 7400 may perform object detection processing such as detecting people, vehicles, obstacles, signs, or characters on the road surface, or distance detection processing. Based on the received information, the external information detection unit 7400 may perform environmental recognition processing to recognize rainfall, fog, or road surface conditions. Based on the received information, the external information detection unit 7400 may calculate the distance to an object outside the vehicle.

[0105] Furthermore, the external information detection unit 7400 may perform image recognition processing or distance detection processing to recognize people, vehicles, obstacles, signs, or characters on the road surface based on the received image data. The external information detection unit 7400 may perform distortion correction or alignment processing on the received image data, and may also synthesize image data captured by different imaging units 7410 to generate an overhead view image or a panoramic image. The external information detection unit 7400 may also perform viewpoint transformation processing using image data captured by different imaging units 7410.

[0106] The in-vehicle information detection unit 7500 detects information inside the vehicle. The in-vehicle information detection unit 7500 is connected to, for example, a driver status detection unit 7510 that detects the driver's state. The driver status detection unit 7510 may include a camera that images the driver, a biosensor that detects the driver's biometric information, or a microphone that collects sounds inside the vehicle. The biosensor is installed, for example, on the seat or steering wheel and detects the biometric information of a passenger sitting in the seat or a driver holding the steering wheel. Based on the detection information input from the driver status detection unit 7510, the in-vehicle information detection unit 7500 may calculate the driver's level of fatigue or concentration, or determine whether the driver is dozing off. The in-vehicle information detection unit 7500 may perform processing such as noise cancellation on the collected audio signals.

[0107] The integrated control unit 7600 controls the overall operation of the vehicle control system 7000 according to various programs. An input unit 7800 is connected to the integrated control unit 7600. The input unit 7800 is implemented by a device that can be operated by the passenger, such as a touch panel, buttons, a microphone, a switch, or a lever. The integrated control unit 7600 may also receive data obtained by voice recognition of voice input from the microphone. The input unit 7800 may be a remote control device using infrared or other radio waves, or an external device such as a mobile phone or PDA (Personal Digital Assistant) that is compatible with the operation of the vehicle control system 7000. The input unit 7800 may be a camera, in which case the passenger can input information by gesture. Alternatively, data obtained by detecting the movement of a wearable device worn by the passenger may be input. Furthermore, the input unit 7800 may include, for example, an input control circuit that generates an input signal based on the information input by the passenger using the above input unit 7800 and outputs it to the integrated control unit 7600. Passengers and others can input various data or instruct the vehicle control system 7000 to perform processing operations by operating this input unit 7800.

[0108] The memory unit 7690 may include a ROM (Read Only Memory) for storing various programs executed by a microcomputer, and a RAM (Random Access Memory) for storing various parameters, calculation results, or sensor values. The memory unit 7690 may also be implemented using a magnetic storage device such as an HDD (Hard Disk Drive), a semiconductor storage device, an optical storage device, or a magneto-optical storage device.

[0109] The general-purpose communication interface 7620 is a general-purpose communication interface that mediates communication between the vehicle and various devices present in the external environment 7750. The general-purpose communication interface 7620 may implement cellular communication protocols such as GSM (Global System of Mobile communications), WiMAX (registered trademark), LTE (registered trademark) (Long Term Evolution), or LTE-A (LTE-Advanced), or other wireless communication protocols such as wireless LAN (also known as Wi-Fi (registered trademark)) or Bluetooth (registered trademark). The general-purpose communication interface 7620 may connect to devices (e.g., application servers or control servers) located on an external network (e.g., the Internet, a cloud network, or a carrier-specific network) via, for example, a base station or access point. The general-purpose communication interface 7620 may also connect to terminals located near the vehicle (e.g., terminals of drivers, pedestrians, or shops, or MTC (Machine Type Communication) terminals) using, for example, P2P (Peer To Peer) technology.

[0110] The Dedicated Communication I / F 7630 is a communication interface that supports communication protocols developed for use in vehicles. The Dedicated Communication I / F 7630 may implement standard protocols such as WAVE (Wireless Access in Vehicle Environment), DSRC (Dedicated Short Range Communications), or cellular communication protocols, which are combinations of lower-layer IEEE 802.11p and upper-layer IEEE 1609. The Dedicated Communication I / F 7630 typically performs V2X communication, a concept that includes one or more of the following: vehicle-to-vehicle communication, vehicle-to-infrastructure communication, vehicle-to-home communication, and vehicle-to-pedestrian communication.

[0111] The positioning unit 7640 performs positioning by receiving GNSS signals from GNSS (Global Navigation Satellite System) satellites (for example, GPS signals from GPS (Global Positioning System) satellites) and generates location information including the vehicle's latitude, longitude, and altitude. The positioning unit 7640 may also determine its current location by exchanging signals with a wireless access point, or it may acquire location information from a terminal such as a mobile phone, PHS, or smartphone that has a positioning function.

[0112] The beacon receiver 7650 receives radio waves or electromagnetic waves transmitted from, for example, a radio station installed on a road, and obtains information such as the current location, traffic congestion, road closures, or travel time. The functions of the beacon receiver 7650 may also be included in the dedicated communication interface 7630 described above.

[0113] The In-Vehicle Equipment I / F 7660 is a communication interface that mediates connections between the microcomputer 7610 and various in-vehicle equipment 7760 located inside the vehicle. The In-Vehicle Equipment I / F 7660 may establish a wireless connection using wireless communication protocols such as Wi-Fi, Bluetooth®, NFC (Near Field Communication), or WUSB (Wireless USB). Furthermore, the in-vehicle equipment I / F 7660 may establish a wired connection such as USB (Universal Serial Bus), HDMI (Registered Trademark) (High-Definition Multimedia Interface), or MHL (Mobile High-Definition Link) via connection terminals (and, if necessary, cables) not shown. The in-vehicle equipment 7760 may include, for example, at least one of the following: a mobile device or wearable device owned by a passenger, or an information device brought into or installed in the vehicle. The in-vehicle equipment 7760 may also include a navigation device that performs route searching to any destination. The in-vehicle equipment I / F 7660 exchanges control signals or data signals with these in-vehicle equipment 7760s.

[0114] The in-vehicle network interface 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The in-vehicle network interface 7680 transmits and receives signals and other data in accordance with a predetermined protocol supported by the communication network 7010.

[0115] The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 according to various programs based on information acquired via at least one of the general-purpose communication I / F 7620, dedicated communication I / F 7630, positioning unit 7640, beacon receiver 7650, in-vehicle equipment I / F 7660, and in-vehicle network I / F 7680. For example, the microcomputer 7610 may calculate control target values ​​for the drive force generator, steering mechanism, or braking device based on acquired in-vehicle and out-of-vehicle information and output control commands to the drive system control unit 7100. For example, the microcomputer 7610 may perform coordinated control aimed at realizing ADAS (Advanced Driver Assistance System) functions, including vehicle collision avoidance or impact mitigation, following driving based on distance between vehicles, maintaining vehicle speed, vehicle collision warning, or vehicle lane departure warning. Furthermore, the microcomputer 7610 may perform cooperative control for purposes such as autonomous driving, where the vehicle drives autonomously without driver intervention, by controlling the drive force generating device, steering mechanism, or braking device, etc., based on the acquired information about the vehicle's surroundings.

[0116] The microcomputer 7610 may generate three-dimensional distance information between the vehicle and surrounding structures, people, and other objects based on information acquired via at least one of the general-purpose communication I / F 7620, dedicated communication I / F 7630, positioning unit 7640, beacon receiver 7650, in-vehicle equipment I / F 7660, and in-vehicle network I / F 7680, and create local map information including surrounding information of the vehicle's current location. Furthermore, the microcomputer 7610 may predict dangers such as vehicle collision, proximity of pedestrians, or entry into a closed road based on the acquired information, and generate a warning signal. The warning signal may, for example, be a signal to generate a warning sound or illuminate a warning lamp.

[0117] The audio-image output unit 7670 transmits at least one of audio and image output signals to an output device capable of visually or audibly notifying the vehicle's occupants or those outside the vehicle. In the example in Figure 20, the output devices are exemplified as an audio speaker 7710, a display unit 7720, and an instrument panel 7730. The display unit 7720 may include, for example, at least one of an onboard display and a head-up display. The display unit 7720 may also have an AR (Augmented Reality) display function. The output device may be other devices besides these, such as headphones, wearable devices such as glasses-type displays worn by occupants, projectors, or lamps. If the output device is a display device, the display device visually displays the results obtained from various processes performed by the microcomputer 7610 or information received from other control units in various formats such as text, images, tables, and graphs. If the output device is an audio output device, the audio output device converts the audio signal, consisting of reproduced audio data or sound data, into an analog signal and outputs it audibly.

[0118] In the example shown in Figure 20, at least two control units connected via the communication network 7010 may be integrated into a single control unit. Alternatively, each control unit may be composed of multiple control units. Furthermore, the vehicle control system 7000 may include other control units not shown. Also, in the above description, some or all of the functions performed by one control unit may be assigned to other control units. In other words, as long as information is transmitted and received via the communication network 7010, predetermined calculation processing may be performed by any of the control units. Similarly, a sensor or device connected to one control unit may be connected to another control unit, and multiple control units may transmit and receive detection information to each other via the communication network 7010.

[0119] Furthermore, the computer program for realizing each function of the optical detection device 1 according to this embodiment, as described with reference to Figure 1, etc., can be implemented in any control unit or the like. Alternatively, a computer-readable recording medium containing such a computer program can be provided. Examples of recording media include magnetic disks, optical disks, magneto-optical disks, flash memory, etc. The computer program may also be distributed, for example, via a network, without using a recording medium.

[0120] In the vehicle control system 7000 described above, the optical detection device 1 according to this embodiment, as described with reference to Figure 1, can be applied to the integrated control unit 7600 of the application example shown in Figure 20.

[0121] Furthermore, at least some of the components of the photodetector 1 described using Figure 1, etc., may be implemented in a module for the integrated control unit 7600 shown in Figure 20 (for example, an integrated circuit module consisting of a single die). Alternatively, the photodetector 1 described using Figure 1 may be implemented by multiple control units of the vehicle control system 7000 shown in Figure 20.

[0122] Furthermore, this technology can take the following configuration. (1) A photoelectric conversion region having multiple pixels, The photoelectric conversion region is stacked on the photoelectric conversion region and comprises an optical control region that controls the direction of light propagation to the photoelectric conversion region, The light control region has a pixel control region having a microstructure for each of the plurality of pixels, The aforementioned pixel control region is a light detection device that controls the propagation direction of light within the aperture range according to the image height. (2) The photodetector according to (1), wherein the plurality of pixel control regions corresponding to the plurality of pixels control the aperture range by making at least one of the pitch diameter of the microstructure, the pitch spacing between the microstructures, the gap spacing between the microstructures, and the number of pitches of the microstructures different according to the image height. (3) The photodetector according to (1) or (2), wherein the pixel control region increases the aperture range as the image height increases and decreases the aperture range as the image height decreases. (4) A photoelectric conversion region having multiple pixels, The system comprises an optical control region positioned on the side of the photoelectric conversion region that is incident on the side of the photoelectric conversion region, and which controls the direction of light propagation to the photoelectric conversion region, The light control region has a pixel control region having a microstructure for each of the plurality of pixels, A light detection device that controls the aperture range corresponding to the amount of light incident on the corresponding pixel control region by making at least one of the following different depending on the image height: the pitch diameter of the microstructure, the pitch spacing between the microstructures, the gap spacing between the microstructures, and the number of pitches of the microstructures. (5) The light detection device according to any one of (1) to (4), wherein the pixel control region propagates more light to the photoelectric conversion region as the image height increases, and less light to the photoelectric conversion region as the image height decreases. (6) The photoelectric conversion region has a plurality of color pixels for each of the plurality of pixels, The light control region has a pixel control region for each of the plurality of color pixels, The photodetector according to any one of (1) to (5), wherein the pixel control region controls the direction of light propagation of the amount of light according to the wavelength of the incident light and the image height. (7) The photodetector according to (6), wherein the pixel control region causes the rate of change of the amount of incident light with respect to the change in image height to differ depending on the wavelength of the incident light. (8) The light detection device according to (7), wherein each of the plurality of pixel control regions corresponding to the plurality of color pixels contained in a single pixel controls the aperture range based on the difference in the number of color pixels of each color within the single pixel. (9) The light detection device according to (8), wherein the aperture range is increased to transmit more light in the pixel control region corresponding to a color pixel with a small number of color pixels within a single pixel. (10) A color filter region is provided between the optical control region and the photoelectric conversion region, corresponding to the plurality of color pixels, The aforementioned color filter region has multiple color filter sections for each pixel, The light detection device according to any one of (6) to (9), wherein the pixel control region controls the aperture range based on the difference in the number of each color of the plurality of color filter sections. (11) The optical detection apparatus according to any one of (1) to (10), wherein the plurality of pixel control regions corresponding to the plurality of pixels are made of different materials of the microstructure according to the image height. (12) The microstructure is Multiple columnar members are arranged spaced apart along the light incident surface, It comprises a base member that covers the periphery of the plurality of columnar members, The photodetector according to (11), wherein the plurality of pixel control regions corresponding to the plurality of pixels are made of different materials for at least one of the columnar member and the base member, depending on the image height. (13) The light detection device according to any one of (1) to (12), wherein pupil correction for incident light is performed in at least some of the pixel control regions among the plurality of pixel control regions corresponding to the plurality of pixels. (14) The light detection device according to (13), wherein the pupil correction amount is increased for the pixel control area located closer to the periphery than the central side of the light control area. (15) Pupil correction is performed by shifting the pixel control region within the light control region along the light incident surface with respect to the corresponding pixel in the photoelectric conversion region. The light detection device according to (14), wherein the amount by which the pixel control region within the light control region is shifted relative to the corresponding pixel in the photoelectric conversion region is increased for pixel control regions located closer to the periphery than to the center of the light control region. (16) Pupil correction is performed by shifting the pixel control area within the light control area along the light incident surface with respect to the corresponding color filter portion within the color filter area. The light detection device according to (10), wherein the amount by which the pixel control region is shifted relative to the corresponding color filter portion in the color filter region is increased for pixel control regions located closer to the periphery than the central side of the light control region. (17) The optical control region is A first optical control unit having a first microstructure, The first optical control unit is stacked with the second optical control unit having a second microstructure, The first optical control unit and the second optical control unit each have a pixel control region having a microstructure for each of the plurality of pixels, Pupil correction is performed by shifting the pixel control region in the first light control unit along the light incident surface relative to the corresponding pixel control region in the second light control unit. The light detection device according to (14), wherein the amount by which the pixel control region in the first light control unit is shifted relative to the corresponding pixel control region in the second light control unit is increased for pixel control regions located closer to the periphery than the central side of the light control region.

[0123] The aspects of this disclosure are not limited to the individual embodiments described above, but include various modifications that a person skilled in the art could conceive, and the effects of this disclosure are not limited to those described above. In other words, various additions, modifications, and partial deletions are possible, as long as they do not depart from the conceptual idea and spirit of this disclosure derived from the claims and their equivalents. [Explanation of symbols]

[0124] 1. Photodetector, 2. Pixel array section, 3. Vertical drive circuit, 4. Column signal processing circuit, 5. Horizontal drive circuit, 6. Output circuit, 7. Control circuit, 10. Adjacent pixels, 10. Pixels, 10c. Color pixels, 11. Photoelectric conversion area, 12. Lens, 13. Optical control area (color splitter), 13a. First optical control section, 13b. Second optical control section, 14. Microstructure, 14b. Base member, 14p. Pillar section, 15. Color filter area, 16. Aperture range, 17. Pixel control area, 18. Light-shielding wall, 19. Light-shielding wall, 20. Insulating layer

Claims

1. A photoelectric conversion region having multiple pixels, The photoelectric conversion region is stacked on the photoelectric conversion region and comprises an optical control region that controls the direction of light propagation to the photoelectric conversion region, The light control region has a pixel control region having a microstructure for each of the plurality of pixels, The pixel control region is a light detection device that controls the direction of light propagation within the aperture range according to the image height, such that the aperture range gradually widens from the center to the periphery of the photoelectric conversion region.

2. The photodetector according to claim 1, wherein the plurality of pixel control regions corresponding to the plurality of pixels control the aperture range by varying at least one of the pitch diameter of the microstructure, the pitch spacing between two adjacent microstructures, the gap spacing between two adjacent microstructures, and the number of pitches of the microstructure, according to the image height.

3. The photodetector according to claim 1, wherein the pixel control region increases the aperture range as the image height increases and decreases the aperture range as the image height decreases.

4. A photoelectric conversion region having multiple pixels, The system comprises an optical control region positioned on the side of the photoelectric conversion region that is incident on the side of the photoelectric conversion region, and which controls the direction of light propagation to the photoelectric conversion region, The light control region has a pixel control region having a microstructure for each of the plurality of pixels, A light detection device that controls the aperture range corresponding to the amount of light incident on the corresponding pixel control region by making at least one of the following different depending on the image height: the pitch diameter of the microstructure, the pitch spacing between two adjacent microstructures, the gap spacing between two adjacent microstructures, and the number of pitches of the microstructure.

5. The photodetector according to claim 1, wherein the pixel control region propagates more light to the photoelectric conversion region as the image height increases, and propagates less light to the photoelectric conversion region as the image height decreases.

6. The photoelectric conversion region has multiple color pixels for each of the multiple pixels, The light control region has a pixel control region for each of the plurality of color pixels, The light detection device according to claim 1, wherein the pixel control region controls the direction of light propagation of the amount of light according to the wavelength of the incident light and the image height.

7. The photodetector according to claim 6, wherein the pixel control region varies the rate of change of the amount of incident light with respect to the change in image height depending on the wavelength of the incident light.

8. The photodetector according to claim 7, wherein each of the plurality of pixel control regions corresponding to the plurality of color pixels contained in a single pixel controls the aperture range based on the difference in the number of color pixels of each color within the single pixel.

9. The light detection device according to claim 8, wherein the aperture range is increased to transmit more light in the pixel control region corresponding to a color pixel with a smaller number of color pixels within a single pixel.

10. The optical control region and the photoelectric conversion region are interposed to include a color filter region corresponding to the plurality of color pixels, The aforementioned color filter region has multiple color filter sections for each pixel, The light detection device according to claim 6, wherein the pixel control region controls the aperture range based on the difference in the number of each color of the plurality of color filter sections.

11. The optical detection device according to claim 1, wherein the plurality of pixel control regions corresponding to the plurality of pixels control the material of the microstructure according to the image height.

12. The aforementioned microstructure is Multiple columnar members are arranged spaced apart along the light incident surface, It comprises a base member that covers the periphery of the plurality of columnar members, The photodetector according to claim 11, wherein the plurality of pixel control regions corresponding to the plurality of pixels control the material of at least one of the columnar member and the base member according to the image height.

13. The light detection device according to claim 1, wherein at least some of the pixel control regions corresponding to the plurality of pixels perform pupil correction for incident light.

14. The light detection device according to claim 13, wherein the pupil correction amount is increased for the pixel control region located closer to the periphery than the central side of the light control region.

15. Pupil correction is performed by shifting the pixel control region within the light control region along the light incident surface relative to the corresponding pixel in the photoelectric conversion region. The light detection device according to claim 14, wherein the amount by which the pixel control region within the light control region is shifted relative to the corresponding pixel in the photoelectric conversion region is increased for pixel control regions located closer to the periphery than to the center of the light control region.

16. Pupil correction is performed by shifting the pixel control region within the light control region along the light incident surface relative to the corresponding color filter portion within the color filter region. The light detection device according to claim 10, wherein the amount by which the pixel control region is shifted relative to the corresponding color filter portion in the color filter region is increased for pixel control regions located closer to the periphery than the central side of the light control region.

17. The aforementioned optical control region is A first optical control unit having a first microstructure, The first optical control unit is laminated with the second optical control unit having a second microstructure, The first optical control unit and the second optical control unit each have a pixel control region having a microstructure for each of the plurality of pixels, Pupil correction is performed by shifting the pixel control region in the first light control unit along the light incident surface relative to the corresponding pixel control region in the second light control unit. The light detection device according to claim 14, wherein the amount by which the pixel control region in the first light control unit is shifted relative to the corresponding pixel control region in the second light control unit is increased for pixel control regions located closer to the periphery than the central side of the light control region.

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