Light detection device, imaging device, and electronic apparatus

Abstract

[Problem] To improve the sensitivity of pixels for acquiring an image plane phase difference. [Solution] A light detection device provided with a pixel array, a conversion unit, and a phase difference detection unit. The pixel array is provided with a plurality of pixel groups arranged in a two-dimensional array pattern. The conversion section is provided in at least each of the pixel groups, and converts an analog signal based on an intensity of light acquired in the pixel groups into a digital signal. The phase difference detection unit detects a phase difference on the basis of the digital signal generated by the conversion unit. Each of the pixel groups includes a plurality of light-receiving pixels including at least a first light-receiving pixel and a second light-receiving pixel, and has an on-chip lens disposed on an incident surface side of the plurality of light-receiving pixels. The phase difference detection unit detects a phase difference on the basis of a first digital signal corresponding to an analog signal output from the first light-receiving pixel and a second digital signal corresponding to an analog signal output from the second light-receiving pixel.

Description

Technical Field

[0001] This disclosure relates to optical detection devices, camera devices, and electronic devices. Background Technology

[0002] Solid-state imaging elements equipped with an analog-to-digital converter (ADC) for each pixel have a structure characterized by comparator circuitry within the pixel and an on-chip lens (OCL) within each pixel. In such a configuration, the pixel used to acquire image plane phase difference has a structure where the pixel is shielded by a light-shielding film such as a metal film, and there is a problem of sensitivity degradation of the image plane phase difference pixel. Existing technical documents Patent documents

[0003] Patent Document 1: Japanese Patent Application Publication No. 2022-033756 Summary of the Invention The problem the invention aims to solve

[0004] Therefore, one of the non-limiting problems to be solved by the embodiments of this disclosure is to improve the sensitivity of pixels used to acquire image plane phase differences. The problem to be solved by the embodiments of this disclosure may correspond to the effects described in the embodiments as non-limiting examples. That is, a problem corresponding to at least one effect described in the description of the embodiments of this disclosure may be a problem that this disclosure seeks to solve. Solution to the problem

[0005] In one embodiment, the light detection device includes a pixel array, a conversion unit, and a phase difference detection unit. The pixel array comprises multiple pixel groups arranged in a two-dimensional array. The conversion unit is provided for at least each of the pixel groups, and converts analog signals based on the intensity of light obtained in the pixel group into digital signals. The phase difference detection unit detects the phase difference based on the digital signal generated by the conversion unit. The pixel group includes: A plurality of light-receiving pixels, including at least a first light-receiving pixel and a second light-receiving pixel, and An on-chip lens is arranged on the incident surface side of the plurality of light-receiving pixels. The phase difference detection unit detects the phase difference based on a first digital signal corresponding to the analog signal output from the first light receiving pixel and a second digital signal corresponding to the analog signal output from the second light receiving pixel.

[0006] The conversion unit can be configured for each of the plurality of light-receiving pixels.

[0007] The plurality of light-receiving pixels can receive light through a global shutter method, convert the analog signal into the digital signal, and output the digital signal.

[0008] The phase difference detection unit can detect the phase difference based on signals output from the first light-receiving pixel and the second light-receiving pixel contained in the same pixel group.

[0009] The phase difference detection unit can detect the phase difference based on signals output from the first light-receiving pixel and the second light-receiving pixel included in different pixel groups.

[0010] The first light-receiving pixel and the second light-receiving pixel can be positioned at a position offset in the row direction within the pixel group.

[0011] The first light-receiving pixel and the second light-receiving pixel can be positioned at a position offset in the column direction within the pixel group.

[0012] The plurality of light-receiving pixels belonging to the pixel group can share a floating diffusion region.

[0013] The plurality of light-receiving pixels belonging to the pixel group can convert the analog signal into the digital signal within the pixel group using a rolling shutter method.

[0014] The floating diffusion region of each of the plurality of light-receiving pixels belonging to the pixel group can be set at a position away from the light-focusing position in the top view.

[0015] In one embodiment, the camera device includes a pixel array, a conversion unit, a phase difference detection unit, and an output unit. The pixel array comprises multiple pixel groups arranged in a two-dimensional array. The conversion unit is provided for at least each of the pixel groups, and converts analog signals based on the intensity of light obtained in the pixel group into digital signals. The phase difference detection unit detects the phase difference based on the digital signal generated by the conversion unit. The output unit outputs the phase difference based on the digital signal generated by the conversion unit. The pixel group includes: A plurality of light-receiving pixels, including at least a first light-receiving pixel and a second light-receiving pixel, and An on-chip lens is arranged on the incident surface side of the plurality of light-receiving pixels. The phase difference detection unit detects the phase difference based on a first digital signal corresponding to the analog signal output from the first light receiving pixel and a second digital signal corresponding to the analog signal output from the second light receiving pixel.

[0016] In one embodiment, the electronic device includes a light detection device or a camera device according to any of the above. Attached Figure Description

[0017] Figure 1 This is a block diagram schematically illustrating an example of a light detection device according to an embodiment. Figure 2 This is a schematic diagram illustrating an example of a pixel array according to an embodiment. Figure 3 This is a schematic diagram illustrating an example of a pixel array according to an embodiment. Figure 4 This is a schematic diagram illustrating an example of a light-receiving pixel according to an embodiment. Figure 5 This is a schematic diagram illustrating an example of an on-chip lens according to an embodiment. Figure 6 This is a schematic diagram illustrating an example of a pixel array according to an embodiment. Figure 7 This is a schematic diagram illustrating an example of a pixel array according to an embodiment. Figure 8 This is an example illustration of a top perspective view of a pixel group according to an embodiment. Figure 9 This is an example illustration of a top perspective view of a pixel group according to an embodiment. Figure 10 This is an example illustration of a top perspective view of a pixel group according to an embodiment. Figure 11 This is an example illustration of a top perspective view of a pixel group according to an embodiment. Figure 12 This is a block diagram illustrating an example of a schematic structure of a vehicle control system. Figure 13 This is an explanatory diagram illustrating an example of the installation location of the vehicle exterior information detection unit and the camera unit. Detailed Implementation

[0018] The embodiments of this disclosure will now be described with reference to the accompanying drawings. The drawings are for illustrative purposes, but the shape, size, and dimensional proportions of the various parts in the actual device may not be as shown in the drawings. Furthermore, since the drawings are shown in a simplified manner, other structures necessary for implementation are appropriately provided in addition to those shown in the drawings.

[0019] Figure 1This is a schematic diagram illustrating an example of a light detection apparatus according to an embodiment. The light detection apparatus 1 includes at least a pixel array 10, a row selection circuit 12, a column selection circuit 14, an AD conversion circuit 16, and a signal processing circuit 18. The light detection apparatus 1 also includes structures necessary for light detection, such as a control unit (control circuit) for controlling each circuit and a power supply unit (power supply circuit) for supplying power to each circuit. An example of the light detection apparatus 1 is a solid-state imaging device that generates image data.

[0020] The light detection device 1 acquires image information based on the intensity of light applied to the pixel array 10, and obtains the phase difference based on the position of the pixels. This phase difference can be a phase difference on the image plane.

[0021] Pixel array 10 is a region that receives light. Pixel array 10 comprises pixels in the form of a two-dimensional array.

[0022] The row selection circuit 12 scans one row of the pixel array 10 to sequentially output the signal acquired by the pixel belonging to that row to the signal processing circuit 18.

[0023] The column selection circuit 14 selects a column in the pixel array 10 to specify the column in the row scanned by the row selection circuit 12, and outputs the signal to the signal processing circuit 18.

[0024] The AD conversion circuit 16 converts the analog signals generated by the pixels belonging to the pixel array 10 through photoelectric conversion into digital signals and outputs the digital signals. As an example, the AD conversion circuit 16 is provided in the circuit of each pixel belonging to the pixel array 10. The AD conversion circuit 16 operates as a converter that converts analog signals into digital signals in the light detection device 1.

[0025] The AD conversion circuit 16 can be arranged as part of the pixel circuit of each pixel, and by providing the AD conversion circuit 16 for each pixel, image data can be acquired using a global shutter method. In this case, the transmission transistor in each pixel circuit may include a memory that holds the signal value of a frame.

[0026] The signal processing circuit 18 is a circuit that performs signal processing on the digital signal converted by the AD conversion circuit 16. The signal processing circuit 18 can generate image data from the digital signal and perform various filtering and color processing, etc. As a signal processing function, the signal processing circuit 18 can also obtain the phase difference, especially the image plane phase difference, based on the signals output from multiple pixels from the AD conversion circuit 16.

[0027] For example, the signal processing circuit 18 can acquire the phase difference of light reflected, transmitted, or irradiated from the same position of the subject based on the output of a first pixel (first light receiving pixel) arranged at a certain position and the output of a second pixel (second light receiving pixel) arranged at a different position from the first pixel, thereby acquiring the phase difference on the image plane. In this case, a part of the signal processing circuit 18 functions as a phase difference detection unit of the light detection device 1.

[0028] Note that the phase difference can be calculated from the acquired signal values ​​using general methods. For example, the signal processing circuit 18 can acquire the image plane phase difference using any conventional phase difference calculation method that calculates the phase difference based on the pixel values ​​of the left half and the right half of the same row that are blocked.

[0029] The following text will illustrate the construction of pixels belonging to pixel array 10 through some non-limiting examples.

[0030] (First Implementation) Figure 2 This is an illustration showing an example of the arrangement of pixel groups in pixel array 10 according to an embodiment. In pixel array 10, pixel groups 100 are arranged in a two-dimensional array.

[0031] Pixel group 100 is arranged in pixel array 10 to form a two-dimensional array relative to a first direction and a second direction intersecting the first direction. The first direction is, for example, a row direction, and the second direction is, for example, a column direction.

[0032] Each pixel group 100 includes multiple light-receiving areas (light-receiving elements, light-receiving pixels) and generates and outputs analog signals based on the intensity of light illuminating each light-receiving area. Furthermore, the pixel group 100 may specifically include an AD conversion circuit 16, which is provided for each light-receiving area (light-receiving pixel) belonging to the pixel group 100, and is capable of converting the analog signals generated in the light-receiving areas into digital signals for each pixel group 100 and outputting the digital signals. As described above, by providing an AD conversion circuit 16 for each light-receiving area of ​​the pixel group 100, a signal for a global shutter method can be output.

[0033] Figure 3 This is a diagram illustrating a more specific example of the arrangement of pixel groups. For example, in pixel group 100, pixel group 100R that receives red light, pixel group 100G that receives green light, and pixel group 100b that receives blue light can be arranged in a Bayer array.

[0034] Not limited to Figure 3For example, a pattern can be adopted in which each pixel group 100 receives light of a predetermined color. For instance, pixel groups 100 can be configured with light-receiving areas that receive visible light (such as pixel groups 100 that receive white light and pixel groups 100 that receive various colors of light such as cyan, magenta, and yellow), or pixel groups 100 can be configured to receive light in bands other than visible light (such as pixel groups 100 that receive ultraviolet light and infrared light (including plasma filters)).

[0035] Figure 4 This is a schematic diagram illustrating an example of the arrangement of light-receiving pixels in pixel group 100 according to an embodiment. As a non-limiting example, pixel group 100 includes light-receiving pixel 102, light-receiving pixel 104, light-receiving pixel 106, and light-receiving pixel 108.

[0036] As shown in the figure, pixel group 100 includes, for example, 2x2 light-receiving pixels, which can work together as a single light-receiving area. As described above, as light-receiving areas corresponding to the same color, pixel group 100 includes, for example, light-receiving pixel 102, light-receiving pixel 104, light-receiving pixel 106, and light-receiving pixel 108.

[0037] Light-receiving pixels 102, 104, 106, and 108 each include a light-receiving region (photoelectric conversion region). In the pixel group 100, each region generates an analog signal based on the intensity of the incident light. The analog signal obtained in the light-receiving region can be converted into a digital signal by an AD conversion circuit 16 provided for each light-receiving pixel, and the digital signal is output. That is, the pixel group 100 can output the digital signal from light-receiving pixels 102, 104, 106, and 108 as a color signal.

[0038] For example, the signal processing circuit 18 can use the average value of the signal values ​​output from the light receiving pixel 102, light receiving pixel 104, light receiving pixel 106 and light receiving pixel 108 as the pixel value, and as the intensity of the light incident on the pixel group 100.

[0039] As another example, mosaic or color matrix processing can be performed based on the signal value output by each light-receiving pixel to obtain the appropriate color output value. For example, this can be achieved by basing the signal value on the signal value output by each light-receiving pixel. Figure 3 The positions of light-receiving pixels 102, 104, 106, and 108 in each pixel group 100 of the Bayer array shown are weighted to perform mosaic processing.

[0040] An on-chip lens 110 is disposed on a plurality of light-receiving pixels on the incident surface side of the pixel group 100. The on-chip lens 110 is a lens that appropriately converges the light incident on the pixel group 100.

[0041] Figure 5 This is a simplified schematic diagram of pixel group 100 and on-chip lens 110 as viewed from the front. Figure 4 (Cross-sectional view of centerline AA). As shown in the figure, the lens 110 on the chip is disposed on the light-receiving surface side of the pixel group 100.

[0042] The light-shielding film 112 is a film that appropriately controls the light-receiving area of ​​the light-receiving pixels in the pixel group 100, and is, for example, a film containing a material that appropriately shields the wavelength of light received by the pixel group 100, such as a metal thin film, a semiconductor thin film, or an insulating thin film (oxide film). The light-shielding film 112 is disposed on the light-emitting side of the on-chip lens 110 to prevent light transmitted through the on-chip lens 110 from leaking to adjacent pixels.

[0043] Each light-receiving pixel acquires an analog signal in the photoelectric conversion region 114 based on the intensity of light incident on the light-receiving surface side, and outputs the analog signal to the outside through the transmission transistor TG.

[0044] It should be noted that the color filter and other components of the photoelectric conversion region 114 are omitted from the illustration, but it is assumed that the photoelectric conversion region is properly positioned. Furthermore, a light-shielding film 112 is disposed on the incident surface side of the photoelectric conversion region 114 to partially block light incident on surrounding pixels. The light-shielding film 112 may, for example, be disposed between the color filter and the photoelectric conversion region 114, or it may be disposed above the color filter. That is, the light-shielding film 112 may be disposed directly below the on-chip lens 110, in contact with or not in contact with the on-chip lens 110.

[0045] Furthermore, in the figure, the light-shielding film 112 is arranged to be embedded in the photoelectric conversion region 114, but this disclosure is not limited to this arrangement. The light-shielding film 112 may be disposed on the upper surface of the photoelectric conversion region 114.

[0046] The transmission transistor TG is a transistor that operates to output the analog signal generated in the photoelectric conversion region 114 to the gate of the floating diffusion region. The analog signal propagating to the floating diffusion region is converted into a digital signal in the AD conversion circuit 16 provided for each light receiving pixel (i.e., each photoelectric conversion region), and the digital signal is supplied to the signal processing circuit 18.

[0047] Each photoelectric conversion region 114 is appropriately insulated and arranged by an insulating film. By acquiring a signal based on the intensity of light incident on each photoelectric conversion region 114, the pixel value of each light-receiving pixel in the pixel group can be obtained.

[0048] At this time, for example, by setting light receiving pixel 106 and light receiving pixel 108 as first light receiving pixels and light receiving pixel 102 and light receiving pixel 104 as second light receiving pixels, when pixel group 100 is regarded as a single pixel, the intensity of light incident on the right half can be obtained through the first light receiving pixel and the intensity of light incident on the left half can be obtained through the second light receiving pixel. In the same pixel group 100, at least a portion of the signal processing circuit 18, which operates as a phase difference detection unit, can obtain the left and right phase differences in the same pixel group from the signal values ​​of the first light receiving pixel and the second light receiving pixel set as described above.

[0049] Furthermore, as illustrated schematically, an example of a pixel array according to an embodiment is shown. Figure 6 As shown, the phase difference can also be obtained in pixel group 100a and pixel group 100b, which are two pixel groups located at any position in the same row (first direction).

[0050] For example, the signal processing circuit 18 can obtain the image plane phase difference (general image plane phase difference) along the row direction based on the signal values ​​of the light receiving pixels 106 and 108, which are the first light receiving pixels of the pixel group 100a, and the signal values ​​of the light receiving pixels 102 and 104, which are the second light receiving pixels of the pixel array 101b.

[0051] The settings of the first and second light-receiving pixels are not limited to those described above. For example, Figure 4 Light receiving pixels 104 and 108 can be set as first light receiving pixels, and light receiving pixels 102 and 106 can be set as second light receiving pixels.

[0052] In this case, an example of a pixel array according to an embodiment is illustrated schematically. Figure 7 As shown, the phase difference in the column direction can be obtained in pixel group 100a and pixel group 100b, which are two pixel groups located at any position in the same column (second direction).

[0053] For example, the signal processing circuit 18 can obtain the image plane phase difference along the column direction based on the signal values ​​of the light receiving pixels 104 and 108, which are the first light receiving pixels of the pixel group 100a, and the signal values ​​of the light receiving pixels 102 and 106, which are the second light receiving pixels of the pixel group 100b.

[0054] That is, at least a part of the signal processing circuit 18, which is the phase difference detection unit, can obtain the image plane phase difference in the first direction or the second direction based on the signal values ​​output from the first light receiving pixel and the second light receiving pixel included in different pixel groups 100.

[0055] Since each light-receiving pixel contains a global shutter method of analog-to-digital conversion circuit 16, the phase difference can be appropriately acquired as described above.

[0056] It should be noted that the phase difference is not limited to the phase difference described above, and for example, in two pixel groups 100 located at positions offset by the same number of units in the row and column directions, the image plane phase difference in the 45-degree direction can be obtained based on the pixel value of the light-receiving pixel 108 as the first light-receiving pixel and the signal value of the light-receiving pixel 102 as the second light-receiving pixel. In this case, the following configuration can also be supported: using light-receiving pixels 104, 106, and 108 as the first light-receiving pixels, and using light-receiving pixels 102, 104, and 106 as the second light-receiving pixels.

[0057] Furthermore, the pixel group used to acquire the image plane phase difference can be a pixel group used to acquire light of the same color or a pixel group used to acquire light of different colors. In the case where the phase difference is acquired using a pixel group used to acquire light of different colors, the phase difference can also be acquired based on the signal value weighted for each light band to be acquired.

[0058] As described above, in this embodiment, by providing a light-shielding film on the incident surface side of the pixel, the image plane phase difference can be appropriately obtained using ordinary pixels (light-receiving pixels in the above embodiment) without providing pixels for obtaining the light intensity of different regions within the photoelectric conversion area. Therefore, the phase difference can be obtained without blocking the intensity of light incident from the light-receiving surface side of the pixel, and the image plane phase difference can be appropriately obtained without degrading the signal value in the pixel used to obtain the image plane phase difference.

[0059] Furthermore, since the phase difference can be obtained using ordinary pixels without the need to set up pixels for obtaining the phase difference on the light-receiving surface side via a light-shielding film, the first light-receiving pixel and the second light-receiving pixel can be arbitrarily set as described above. Therefore, by using the pixel group and light-receiving pixels in this disclosure, the image plane phase difference can be appropriately obtained at any time by using pixels belonging to any row and column or pixels belonging to the 45-degree direction.

[0060] It should be noted that the above description indicates that pixel group 100 contains 2x2 light-receiving pixels, that is, 2x2 light-receiving pixels exist in one on-chip lens 110, but this disclosure is not limited to this case. For example, pixel group 100 may contain 3x3 light-receiving pixels or 4x4 light-receiving pixels. In the case of 3x3 light-receiving pixels, the light-receiving pixels are divided into left, middle, and right pixels, and the row-direction phase difference can be obtained by using the left column as the second pixel and the right column as the first pixel, or by using the left and middle columns as the second pixels and the middle and right columns as the second pixels. This also applies to the case of 4x4 light-receiving pixels. Furthermore, this also applies to the column-direction phase difference and the diagonal phase difference.

[0061] Furthermore, the construction of pixels in pixel group 100 is not limited to the case where the same number of light-receiving pixels are included in the row and column directions as described above, but may also include different numbers of light-receiving pixels, such as 2x3 pixels.

[0062] (Second Implementation) In the above embodiments, a method for obtaining phase difference from light-receiving pixels has been described, but in this embodiment, a non-limiting example of component arrangement under the above processing will be described.

[0063] Figure 8 This is a top perspective view illustrating an example of the positional relationship between the photoelectric conversion region 114, the transmission transistor TG, and the floating diffusion region FD in a pixel group according to an embodiment. The figure shows the configuration of each light-receiving pixel belonging to a pixel group 100. The circles indicated by dashed lines represent areas where, for example, an on-chip lens 110 will converge light incident vertically into the light-receiving region.

[0064] like Figure 8 As shown, each light-receiving pixel may include a transmission transistor TG and a floating diffusion region FD that have the same positional relationship as the photoelectric conversion region 114. In this case, the light-receiving pixels in the pixel array 10 can be constructed identically, and it is easy to maintain the overall uniformity of the circuit.

[0065] Figure 9 This is a top perspective view illustrating an example of the positional relationship between the photoelectric conversion region 114, the transfer transistor TG, and the floating diffusion region FD in a pixel group according to an embodiment. Figure 8 The difference is that the floating diffusion region (FD) is located far away from the focusing region.

[0066] Figure 10This is a top perspective view illustrating an example of the positional relationship between the photoelectric conversion region 114, the transfer transistor TG, and the floating diffusion region FD in a pixel group according to an embodiment. Figure 9 Similarly, the floating diffusion region (FD) is positioned away from the focusing region. (And...) Figure 9 In contrast, the light-receiving pixels are arranged to make the distance between the light-gathering area and the floating diffusion area (FD) more uniform.

[0067] By arranging the floating diffusion region FD in such a way Figure 9 and Figure 10 The location shown, away from areas where more light is focused, can reduce parasitic light sensitivity (PLS).

[0068] Figure 11 This is a top perspective view showing the positional relationship between the photoelectric conversion region 114, the transfer transistor TG, and the floating diffusion region FD in a pixel group according to an embodiment. Figure 9 and Figure 10 Conversely, the transmission transistor TG is positioned in a region close to the focusing area. In this arrangement, the floating diffusion region FD can be shared by the light-receiving pixels belonging to pixel group 100.

[0069] The floating diffusion region FD can be shared by multiple light-receiving pixels, meaning that the AD conversion circuit 16 connected via the floating diffusion region FD can be shared by multiple light-receiving pixels belonging to pixel group 100. Unlike any of the above forms, the AD conversion circuit 16 is not set for each light-receiving pixel, but rather for each pixel group 100.

[0070] In this case, compared to the above-described form, the number of AD conversion circuits 16 can be reduced, and the degree of freedom in layout can be increased. Among the multiple light-receiving pixels belonging to pixel group 100, a rolling shutter type signal is acquired. However, since the rolling shutter is only applied to a very small number of light-receiving pixels, an image close to the global shutter speed can be acquired. In such an image, the occurrence of rolling shutter distortion is suppressed, and the phase difference can be acquired.

[0071] As described above, this embodiment allows for the use of various configurations and layouts with a high degree of freedom in relation to its purpose and other structures.

[0072] In embodiments of this disclosure, for example, it is not necessary to shield half of the pixel with a metal film, thus improving sensitivity. Furthermore, due to the use of a global shutter method, image plane phase difference can be acquired without rolling shutter distortion in either the row or column directions. Additionally, as described in the second embodiment, various layouts can be used.

[0073] The light detection device 1 of the above forms can obtain phase difference based on the signal output from multiple light receiving pixels, and can obtain highly sensitive image information in a state where the light is not shielded.

[0074] Furthermore, the light detection device 1 can be used in electronic devices including the aforementioned solid-state camera device, such as camera devices in vehicle-mounted devices, smartphones, tablet terminals, or drones.

[0075] The technology according to the invention is applicable to a variety of products. For example, the technology according to the invention can be implemented in the form of a device installed on any type of mobile body such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility devices, airplanes, drones, ships, robots, construction machinery, and agricultural machinery (tractors).

[0076] Figure 12 This is a block diagram illustrating a schematic construction example of a vehicle control system 7000, which is an example of a mobile body control system applying the technology according to this disclosure. The vehicle control system 7000 includes multiple electronic control units interconnected via a communication network 7010. Figure 12 In the example shown, the vehicle control system 7000 includes 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 the multiple control units can be, for example, an in-vehicle communication network conforming to any standard such as Controller Area Network (CAN), Local Interconnect Network (LIN), Local Area Network (LAN), or FlexRay (registered trademark).

[0077] Each control unit includes: a microcomputer that performs arithmetic processing according to various types of programs; a storage unit that stores programs executed by the microcomputer, parameters for various types of operations, etc.; and drive circuits that drive various types of control target devices. Each control unit also includes: a network interface (I / F) for communicating with other control units via the communication network 7010; and a communication I / F for communicating with devices, sensors, etc. inside and outside the vehicle via wired or wireless communication. Figure 12 The integrated control unit 7600 shown is configured with the following functionalities: a microcomputer 7610, a general communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiver 7650, an in-vehicle device I / F 7660, an audio / image output unit 7670, an in-vehicle network I / F 7680, and a storage unit 7690. Other control units similarly include microcomputers, communication I / Fs, and storage units.

[0078] The drive system control unit 7100 controls the operation of devices related to the vehicle's drive system according to various types of programs. For example, the drive system control unit 7100 functions as a control device for devices such as an internal combustion engine and a drive motor that generate driving force for the vehicle; a driving force transmission mechanism that transmits driving force to the wheels; a steering mechanism that adjusts the vehicle's steering angle; and a braking device that generates braking force for the vehicle. The drive system control unit 7100 may also function as a control device for systems such as anti-lock braking system (ABS) or electronic stability control (ESC).

[0079] The drive system control unit 7100 is connected to the vehicle condition detection unit 7110. For example, the vehicle condition detection unit 7110 includes at least one of the following: a gyroscope sensor for detecting the angular velocity of the vehicle's axial rotational motion, an acceleration sensor for detecting the vehicle's acceleration, and 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, engine speed, or wheel rotation speed. The drive system control unit 7100 performs arithmetic processing using signals input from the vehicle condition detection unit 7110 and controls the internal combustion engine, drive motor, electric power steering, and braking system.

[0080] The vehicle body system control unit 7200 controls the operation of various types of devices installed on the vehicle body according to various types of programs. For example, the vehicle body system control unit 7200 is used as a control device for keyless entry systems, smart key systems, power windows, or various types of lights such as headlights, reversing lights, brake lights, turn signals, and fog lights. In this case, radio waves or various types of switch signals sent from a moving device that serves as a substitute for a key can be input to the vehicle body system control unit 7200. The vehicle body system control unit 7200 receives these input radio waves or signals and controls the vehicle's door locks, power windows, lights, etc.

[0081] The battery control unit 7300 controls the battery 7310, which serves as a power source for driving the motor, according to various types of programs. For example, information about battery temperature, battery output voltage, and remaining battery charge is provided to the battery control unit 7300 from the battery assembly containing the battery 7310. The battery control unit 7300 uses these signals to perform arithmetic processing and to control the temperature of the battery 7310 or to control the cooling devices provided for the battery assembly.

[0082] The exterior information detection unit 7400 detects information about the exterior of the vehicle equipped with the vehicle control system 7000. For example, the exterior information detection unit 7400 is connected to at least one of a camera unit 7410 and an exterior information detection unit 7420. The camera unit 7410 includes at least one of a time-of-flight (ToF) camera, a stereo camera, a single-lens reflex camera, an infrared camera, and other cameras. The exterior information detection unit 7420 includes, for example, at least one of an environmental sensor for detecting current atmospheric or weather conditions and a surrounding information detection sensor for detecting other vehicles, obstacles, pedestrians, etc., in the vicinity of the vehicle equipped with the vehicle control system 7000.

[0083] For example, the environmental sensor may be at least one of a raindrop sensor for detecting rainfall, a fog sensor for detecting fog, a sunlight sensor for detecting sunlight intensity, and a snow sensor for detecting snowfall. The surrounding information detection sensor may be at least one of an ultrasonic sensor, a radar device, and a LIDAR device (light detection and ranging device, or laser imaging detection and ranging device). Each of the camera unit 7410 and the exterior information detection unit 7420 may be provided as an independent sensor or device, or as a device that integrates multiple sensors or devices.

[0084] Figure 13 Examples of the mounting positions of the camera unit 7410 and the vehicle exterior information detection unit 7420 are shown. Camera units 7910, 7912, 7914, 7916, and 7918 are, for example, located at at least one of the following positions on the front nose, side mirrors, rear bumper, and rear door of the vehicle 7900, and on the upper part of the windshield inside the vehicle. The camera unit 7910 located on the front nose and the camera unit 7918 located on the upper part of the windshield inside the vehicle primarily obtain images of the front of the vehicle 7900. The cameras 7912 and 7914 located on the side mirrors primarily obtain images of the sides of the vehicle 7900. The camera unit 7916 located on the rear bumper or rear door primarily obtains images of the rear of the vehicle 7900. The camera unit 7918 located on the upper part of the windshield inside the vehicle is mainly used to detect vehicles, pedestrians, obstacles, signals, traffic signs, lanes, etc., ahead.

[0085] Incidentally, Figure 13 Examples of the camera ranges of camera units 7910, 7912, 7914, and 7916 are shown. Camera range a represents the camera range of camera unit 7910 located at the front nose. Camera ranges b and c represent the camera ranges of camera units 7912 and 7914 located at the side mirrors, respectively. Camera range d represents the camera range of camera unit 7916 located at the rear bumper or rear door. For example, a bird's-eye view of the vehicle 7900 viewed from above can be obtained by overlaying image data captured by camera units 7910, 7912, 7914, and 7916.

[0086] The exterior information detection units 7920, 7922, 7924, 7926, 7928, and 7930, located at the front, rear, sides, corners, and above the windshield inside the vehicle 7900, can be, for example, ultrasonic sensors or radar devices. For instance, the exterior information detection units 7920, 7926, and 7930 located at the front nose, rear bumper, rear door, and above the windshield inside the vehicle 7900 can be LIDAR devices. These exterior information detection units 7920 to 7930 are primarily used to detect vehicles, pedestrians, or obstacles ahead.

[0087] Will return Figure 12 Continuing the explanation, the exterior information detection unit 7400 causes the camera unit 7410 to capture images of the exterior of the vehicle and receives data from the captured images. Additionally, the exterior information detection unit 7400 receives detection information from the exterior information detection section 7420 connected to it. If the exterior information detection section 7420 is an ultrasonic sensor, radar device, or LIDAR device, the exterior information detection unit 7400 emits ultrasonic waves or electromagnetic waves and receives information from the received reflected waves. Based on the received information, the exterior information detection unit 7400 can perform processing such as detecting objects like people, vehicles, obstacles, signs, and characters on the road surface, or processing the distance to detected objects. The exterior information detection unit 7400 can perform environmental recognition processing based on the received information, such as identifying rain, fog, or road conditions. The exterior information detection unit 7400 can calculate the distance to objects outside the vehicle based on the received information.

[0088] Furthermore, based on the received image data, the vehicle exterior information detection unit 7400 can perform image recognition processing to identify people, vehicles, obstacles, signs, or characters on the road surface, or to detect their distance. The vehicle exterior information detection unit 7400 can perform processing on the received image data, such as distortion correction and alignment, and combine image data captured by multiple different cameras 7410 to generate a bird's-eye view or panoramic image. The vehicle exterior information detection unit 7400 can use image data captured by different cameras 7410 to perform viewpoint conversion processing.

[0089] The in-vehicle information detection unit 7500 detects information about the interior of the vehicle. The in-vehicle information detection unit 7500 is connected, for example, to a driver state detection unit 7510 that detects the driver's state. The driver state detection unit 7510 may include a camera that captures an image of the driver, a biosensor that detects the driver's biological information, a microphone that collects sounds from inside the vehicle, etc. The biosensor is disposed, for example, on the seat surface or steering wheel, and detects the biological information of passengers sitting in the seat or the driver holding the steering wheel. Based on the detection information input from the driver state detection unit 7510, the in-vehicle information detection unit 7500 can calculate the driver's fatigue level or concentration level, or determine whether the driver is dozing off. The in-vehicle information detection unit 7500 can perform processing such as noise cancellation on the audio signals obtained by collecting sound.

[0090] The integrated control unit 7600 controls the overall operation within the vehicle control system 7000 according to various types of programs. The integrated control unit 7600 is connected to the input unit 7800. For example, the input unit 7800 may be implemented by a device such as a touch panel, button, microphone, switch, or joystick that allows input by a passenger. Data obtained through voice recognition of voice input via a microphone can be supplied to the integrated control unit 7600. The input unit 7800 may be, for example, a remote control device using infrared or other radio waves, or an external connection device supporting the operation of the vehicle control system 7000, such as a mobile phone or personal digital assistant (PDA). The input unit 7800 may be, for example, a camera. In this case, the passenger can input information through gestures. Alternatively, data obtained by detecting the movement of a wearable device worn by the passenger can be input. Furthermore, the input unit 7800 may include, for example, an input control circuit that generates an input signal based on information input by the passenger using the aforementioned input unit 7800, and outputs the generated input signal to the integrated control unit 7600. Passengers can input various types of data or give instructions for processing operations to the vehicle control system 7000 through the operation input unit 7800.

[0091] The storage unit 7690 may include a read-only memory (ROM) for storing various types of programs executed by a microcomputer and a random access memory (RAM) for storing various parameters, operation results, or sensor values. Furthermore, the storage unit 7690 may be implemented using a magnetic storage device such as a hard disk drive (HDD), a semiconductor storage device, an optical storage device, or a magneto-optical storage device.

[0092] The General Communication I / F 7620 is a widely used communication I / F that regulates communication with various devices present in the external environment 7750. The General Communication I / F 7620 can implement cellular communication protocols such as GSM (Global System for Mobile Communications), WiMAX (Global Microwave Interconnection Access), LTE (Long Term Evolution), or LTE-A Advanced (LTE-A), or other wireless communication protocols such as Wireless LAN (also known as Wi-Fi), Bluetooth, etc. The General Communication I / F 7620 can, for example, connect to devices (e.g., application servers or control servers) existing on external networks (e.g., the Internet, cloud networks, or corporate private networks) via base stations or access points. Additionally, for example, the General Communication I / F 7620 can use peer-to-peer (P2P) technology to connect to terminals appearing near the vehicle (e.g., terminals belonging to drivers, pedestrians, or shops, or machine-type communication (MTC) terminals).

[0093] The Dedicated Communication I / F 7630 is a communication I / F that supports communication protocols developed for use in vehicles. For example, the Dedicated Communication I / F 7630 can implement standard protocols such as Wireless Access in a Vehicle Environment (WAVE), which is a combination of IEEE 802.11p as the lower layer and IEEE 1609 as the upper layer, Dedicated Short Range Communication (DSRC), or cellular communication protocols. The Dedicated Communication I / F 7630 typically performs V2X communication, which includes one or more of the following concepts: vehicle-to-vehicle communication, road-to-vehicle communication, vehicle-to-home communication, and pedestrian-to-vehicle communication.

[0094] For example, the positioning unit 7640 performs positioning by receiving Global Navigation Satellite System (GNSS) signals from GNSS satellites (e.g., GPS signals from Global Positioning System (GPS) satellites) and generates location information including the vehicle's latitude, longitude, and altitude. Incidentally, the positioning unit 7640 can identify its current location by exchanging signals with a wireless access point, or it can obtain location information from a terminal such as a mobile phone, a Personal Handheld Phone System (PHS), or a smartphone with positioning capabilities.

[0095] The beacon receiver 7650 receives, for example, radio waves or electromagnetic waves transmitted from a radio station installed on a road, thereby obtaining information about current location, congestion, road closures, or estimated time. Incidentally, the functionality of the beacon receiver 7650 can be included in the aforementioned dedicated communication I / F 7630.

[0096] The vehicle-mounted device I / F 7660 is a communication interface that mediates the connection between the microcomputer 7610 and various vehicle-mounted devices 7760 present in the vehicle. The vehicle-mounted device I / F 7660 can establish a wireless connection using wireless communication protocols such as Wireless LAN, Bluetooth (registered trademark), Near Field Communication (NFC), or Wireless Universal Serial Bus (WUSB). Alternatively, the vehicle-mounted device I / F 7660 can establish a wired connection via a connection terminal not shown in the figure (and, if necessary, via a cable) through Universal Serial Bus (USB), High Definition Multimedia Interface (HDMI (registered trademark)), Mobile High Definition Link (MHL), etc. For example, the vehicle-mounted device 7760 may include at least one of passenger-owned mobile devices and wearable devices, as well as information devices carried to or attached to the vehicle. The vehicle-mounted device 7760 may also include a navigation device for searching routes to any destination. The vehicle-mounted device I / F 7660 exchanges control signals or data signals with these vehicle-mounted devices 7760.

[0097] The vehicle network I / F 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The vehicle network I / F 7680 sends and receives signals in accordance with the predetermined protocols supported by the communication network 7010.

[0098] The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 according to various types of programs based on information obtained via at least one of a general communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiving unit 7650, an on-board device I / F 7660, and an on-board network I / F 7680. For example, the microcomputer 7610 can calculate control target values ​​for the drive force generating device, steering mechanism, or braking device based on the obtained information about the vehicle's interior and exterior, and output control commands to the drive system control unit 7100. For example, the microcomputer 7610 can perform cooperative control aimed at realizing functions of an advanced driver assistance system (ADAS), including vehicle collision avoidance or mitigation, following distance-based driving, vehicle speed maintenance, vehicle collision warning, and vehicle lane departure warning. In addition, the microcomputer 7610 can control the drive force generating device, steering mechanism, braking device, etc. based on the information obtained about the vehicle's surroundings, and perform cooperative control intended for autonomous driving, which allows the vehicle to drive autonomously without relying on the driver's operation.

[0099] The microcomputer 7610 can generate three-dimensional distance information between the vehicle and objects such as surrounding structures and people based on information obtained via at least one of a general communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiving unit 7650, a vehicle-mounted device I / F 7660, and a vehicle-mounted network I / F 7680, and also generate local map information including surrounding information about the vehicle's current position. Furthermore, the microcomputer 7610 can predict dangers such as vehicle collisions or pedestrians approaching or entering closed roads based on the obtained information, and generate warning signals. For example, the warning signal may be a signal used to generate a warning sound or illuminate a warning light.

[0100] The audio-visual output unit 7670 sends an output signal of at least one of audio and visual information to an output device capable of visually or audibly notifying passengers of the vehicle or the outside of the vehicle. Figure 12 In the example, an audio speaker 7710, a display unit 7720, and a dashboard 7730 are shown as output devices. For example, the display unit 7720 may include at least one of an in-vehicle display and a head-up display. The display unit 7720 may have augmented reality (AR) display functionality. The output device may be other than these, such as headphones, wearable devices such as glasses-type displays worn by passengers, projectors, lamps, etc. When the output device is a display device, the display device visually displays the results obtained from various types of processing performed by the microcomputer 7610 or information received from other control units in various forms such as text, images, tables, and charts. In addition, when the output device is an audio output device, the audio output device converts an audio signal composed of regenerated audio data or sound data into an analog signal and audibly outputs the analog signal.

[0101] Please note that in Figure 12 In the example shown, at least two control units connected to each other via communication network 7010 can be integrated into one control unit. Alternatively, each individual control unit may include multiple control units. Furthermore, the vehicle control system 7000 may include other control units not shown in the figures. Additionally, some or all of the functions performed by one control unit as described above can be assigned to another control unit. That is, any control unit can perform predetermined arithmetic processing as long as information is sent and received via communication network 7010. Similarly, sensors or devices connected to one of the control units can be connected to another control unit, and multiple control units can send and receive detection information to each other via communication network 7010.

[0102] It should be noted that the reference can be installed on any control unit, etc. Figures 1 to 11The computer program for each function of the light detection device 1 is provided. Additionally, a computer-readable recording medium storing this computer program can be provided. For example, the recording medium is a magnetic disk, optical disk, magneto-optical disk, flash memory, etc. Furthermore, the aforementioned computer program can be distributed, for example, via a network without using a recording medium.

[0103] In the aforementioned vehicle control system 7000, refer to Figures 1 to 11 The light detection device 1 described according to this embodiment can be applied to... Figure 12 The application example shown is at least a portion of the camera unit 7410 or the in-vehicle information detection unit 7510.

[0104] The above implementation methods can have the following modes. (1) A light detection device, comprising: A pixel array, which comprises multiple groups of pixels arranged in a two-dimensional array; A conversion unit is provided for at least each of the pixel groups, and converts an analog signal based on the intensity of light obtained in the pixel group into a digital signal; The phase difference detection unit detects the phase difference based on the digital signal generated by the conversion unit, wherein... The pixel group includes: A plurality of light-receiving pixels, including at least a first light-receiving pixel and a second light-receiving pixel, and An on-chip lens is arranged on one side of the incident surface of the plurality of light-receiving pixels; and The phase difference detection unit detects the phase difference based on a first digital signal corresponding to the analog signal output from the first light receiving pixel and a second digital signal corresponding to the analog signal output from the second light receiving pixel. (2) According to the optical detection device described in (1), wherein, The conversion unit is provided for each of the plurality of light-receiving pixels. (3) According to the optical detection device described in (1) or (2), wherein, The plurality of light-receiving pixels receive light through a global shutter method, convert the analog signal into the digital signal, and output the digital signal. (4) The light detection device according to any one of (1) to (3), wherein, The phase difference detection unit detects the phase difference based on signals output from the first light-receiving pixel and the second light-receiving pixel included in the same pixel group. (5) The light detection device according to any one of (1) to (3), wherein, The phase difference detection unit detects the phase difference based on signals output from the first light-receiving pixel and the second light-receiving pixel included in different pixel groups. (6) The light detection device according to any one of (1) to (5), wherein, In the pixel group, the first light-receiving pixel and the second light-receiving pixel are positioned at a position offset in the row direction. (7) The light detection device according to any one of (1) to (5), wherein, In the pixel group, the first light-receiving pixel and the second light-receiving pixel are positioned at a position offset in the column direction. (8) The light detection device according to any one of (1) to (7), wherein, The plurality of light-receiving pixels belonging to the pixel group share a floating diffusion region. (9) According to the optical detection device described in (8), wherein, The plurality of light-receiving pixels belonging to the pixel group convert the analog signal into the digital signal within the pixel group using a rolling shutter method. (10) The light detection device according to any one of (1) to (7), wherein, In the top view, the floating diffusion region of each of the plurality of light-receiving pixels belonging to the pixel group is positioned away from the light-focusing position. (11) A camera device comprising: A pixel array, which comprises multiple groups of pixels arranged in a two-dimensional array; A conversion unit is provided for at least each of the pixel groups, and converts an analog signal based on the intensity of light obtained in the pixel group into a digital signal; A phase difference detection unit detects a phase difference based on the digital signal generated by the conversion unit; and The output unit outputs image data based on the digital signal generated by the conversion unit, wherein... The pixel group includes: A plurality of light-receiving pixels, including at least a first light-receiving pixel and a second light-receiving pixel, and An on-chip lens is arranged on one side of the incident surface of the plurality of light-receiving pixels; and The phase difference detection unit detects the phase difference based on a first digital signal corresponding to the analog signal output from the first light receiving pixel and a second digital signal corresponding to the analog signal output from the second light receiving pixel. (12) An electronic device comprising: The light detection device according to any one of (1) to (10) or the camera device according to (11).

[0117] This disclosure is not limited to the embodiments described above, but also includes various conceivable modifications, and the effects of this disclosure are not limited to the above content. Components in each embodiment can be appropriately combined and applied. That is, various additions, modifications, and partial deletions can be made without departing from the concept and spirit of this disclosure as defined by the claims and their equivalents and similar content. List of reference numerals

[0118] 1: Light detection circuit 10: Pixel Array 100: Pixel group 100R, 100G, 100B: Pixel Group 100a, 100b: Pixel group 102, 104, 106, 108: Light-receiving pixels 110: On-chip lens 112: Light-shielding film 114: Photoelectric conversion region TG: Transmission Transistor FD: Floating Diffusion Region 12: Row scanning circuit 14: Column Selection Circuit 16: AD conversion circuit 18: Signal processing circuit

Claims

1. A light detection device, comprising: A pixel array, which comprises multiple groups of pixels arranged in a two-dimensional array; A conversion unit is provided for at least each of the pixel groups, and converts an analog signal based on the intensity of light obtained in the pixel group into a digital signal; The phase difference detection unit detects the phase difference based on the digital signal generated by the conversion unit, wherein... The pixel group includes: A plurality of light-receiving pixels, including at least a first light-receiving pixel and a second light-receiving pixel, and An on-chip lens arranged on one side of the incident surface of the plurality of light-receiving pixels; and The phase difference detection unit detects the phase difference based on a first digital signal corresponding to the analog signal output from the first light receiving pixel and a second digital signal corresponding to the analog signal output from the second light receiving pixel.

2. The optical detection device according to claim 1, wherein, The conversion unit is provided for each of the plurality of light-receiving pixels.

3. The optical detection device according to claim 1, wherein, The plurality of light-receiving pixels receive light through a global shutter method, convert the analog signal into the digital signal, and output the digital signal.

4. The optical detection device according to claim 1, wherein, The phase difference detection unit detects the phase difference based on signals output from the first light-receiving pixel and the second light-receiving pixel included in the same pixel group.

5. The optical detection device according to claim 1, wherein, The phase difference detection unit detects the phase difference based on signals output from the first light-receiving pixel and the second light-receiving pixel included in different pixel groups.

6. The optical detection device according to claim 1, wherein, In the pixel group, the first light-receiving pixel and the second light-receiving pixel are positioned at a position offset in the row direction.

7. The optical detection device according to claim 1, wherein, In the pixel group, the first light-receiving pixel and the second light-receiving pixel are positioned at a position offset in the column direction.

8. The optical detection device according to claim 1, wherein, The plurality of light-receiving pixels belonging to the pixel group share a floating diffusion region.

9. The optical detection device according to claim 8, wherein, The plurality of light-receiving pixels belonging to the pixel group convert the analog signal into the digital signal within the pixel group using a rolling shutter method.

10. The optical detection device according to claim 1, wherein, In the top view, the floating diffusion region of each of the plurality of light-receiving pixels belonging to the pixel group is positioned away from the light-focusing position.

11. A camera device comprising: A pixel array, which comprises multiple groups of pixels arranged in a two-dimensional array; A conversion unit is provided for at least each of the pixel groups, and converts an analog signal based on the intensity of light obtained in the pixel group into a digital signal; A phase difference detection unit detects a phase difference based on the digital signal generated by the conversion unit; and The output unit outputs image data based on the digital signal generated by the conversion unit, wherein... The pixel group includes: A plurality of light-receiving pixels, including at least a first light-receiving pixel and a second light-receiving pixel, and An on-chip lens arranged on one side of the incident surface of the plurality of light-receiving pixels; and The phase difference detection unit detects the phase difference based on a first digital signal corresponding to the analog signal output from the first light receiving pixel and a second digital signal corresponding to the analog signal output from the second light receiving pixel.

12. An electronic device comprising: The optical detection device according to claim 1.

13. An electronic device comprising: The camera device according to claim 11.

Images