Imaging device and reading control method

Abstract

An imaging device achieves high-precision subject tracking when shooting at a normal frame rate and continues autofocus (AF) processing while suppressing power consumption when shooting at a higher frame rate than normal. The imaging device includes: an imaging element having a plurality of pixels arranged in two dimensions, each pixel including a first photoelectric conversion unit and a second photoelectric conversion unit, the first photoelectric conversion unit receiving a light beam passing through a first portion region of an imaging optical system, and the second photoelectric conversion unit receiving a light beam passing through a second portion region different from the first portion region; and a readout control unit that performs first readout control when a first mode is selected and second readout control when a second mode set to a high frame rate is selected. The first readout control causes the respective charges of the first and second photoelectric conversion units to undergo individual analog-to-digital (AD) conversion to generate pixel signals. The second readout control, in discretely set first pixels, causes the respective charges of the first and second photoelectric conversion units to undergo individual AD conversion to generate first pixel signals, and in second pixels that are not the first pixels, adds the charges of the first and second photoelectric conversion units and then performs AD conversion to generate second pixel signals.

Description

Technical Field

[0001] This invention relates to an imaging device and a reading control method for reading pixel signals from an imaging element. Background Technology

[0002] A shooting device is known that uses a phase difference signal obtained from the image plane of an imaging element for autofocus control. The imaging element capable of outputting this phase difference signal has two photoelectric conversion units that perform pupil division of each pixel for a microlens. If the pixel signals output from the two photoelectric conversion units are used as individual phase difference signals, they can be used for defocus calculation in autofocus (AF). If the pixel signals output from the two photoelectric conversion units are added together as an image signal, the image signals of the effective pixels can be aggregated to generate a frame image as an image of the subject (for example, see Patent Document 1). Recent shooting devices employing such imaging elements perform high-precision AF even in video shooting, maintaining focus even on moving subjects. Furthermore, the total number of pixels in the imaging element is gradually increasing, resulting in improved focusing accuracy.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent document 1: Japanese Patent Application Publication No. 2017-134154. Summary of the Invention

[0006] The problem the invention aims to solve

[0007] The latter mode is popular: by shooting at a higher frame rate than usual and replaying at the normal frame rate, one can enjoy images of subjects moving more slowly and smoothly than they actually are. In high frame rate mode, because pixel signals are read at a higher frame rate than usual, it consumes a lot of power, and in some cases, pixel signal reading and processing cannot keep up. If pixel signal reading and processing cannot keep up, AF processing fails, and the subject cannot be kept in focus.

[0008] The present invention was proposed to solve such a problem by providing a shooting device, etc., which achieves high-precision subject tracking when shooting at a normal frame rate and can continue AF processing while suppressing power consumption when shooting at a higher frame rate than normal.

[0009] Solution for solving the problem

[0010] The imaging apparatus according to a first aspect of the present invention includes: an imaging element having a plurality of pixels arranged in two dimensions, the pixels including a first photoelectric conversion unit and a second photoelectric conversion unit, the first photoelectric conversion unit receiving a light beam passing through a first portion region of an imaging optical system, and the second photoelectric conversion unit receiving a light beam passing through a second portion region different from the first portion region; and a readout control unit that performs first readout control when a first mode is selected, and performs second readout control when a second mode with a frame rate set to a higher frame rate than that set in the first mode is selected, wherein the first readout control causes the respective charges of the first photoelectric conversion unit and the second photoelectric conversion unit to undergo individual AD conversion to generate a pixel signal, and the second readout control causes the respective charges of the first photoelectric conversion unit and the second photoelectric conversion unit to undergo individual AD conversion to generate a first pixel signal in a discretely set first pixel, and in a second pixel that is not the first pixel, the charges of the first photoelectric conversion unit and the second photoelectric conversion unit are added together and then AD converted to generate a second pixel signal.

[0011] Furthermore, the readout control method in the second aspect of the present invention includes: reading pixel signals from an imaging element having a plurality of pixels arranged in two dimensions, the pixels including a first photoelectric conversion unit and a second photoelectric conversion unit, the first photoelectric conversion unit receiving a light beam passing through a first portion region of an imaging optical system, the second photoelectric conversion unit receiving a light beam passing through a second portion region different from the first portion region, determining a mode from a first mode and a second mode in which the frame rate is set higher than that set in the first mode; and performing a first readout control in the first mode and a second readout control in the second mode, wherein the first readout control causes the respective charges of the first photoelectric conversion unit and the second photoelectric conversion unit to undergo AD conversion separately to generate a pixel signal; the second readout control causes the respective charges of the first photoelectric conversion unit and the second photoelectric conversion unit to undergo AD conversion separately to generate a first pixel signal in a discretely set first pixel among the pixels, and in a second pixel among the pixels that is not the first pixel, the charges of the first photoelectric conversion unit and the second photoelectric conversion unit are added together and then AD converted to generate a second pixel signal.

[0012] Invention Effects

[0013] According to the present invention, a shooting device or the like can be provided that achieves high-precision subject tracking when shooting at a normal frame rate, and can continue AF processing while suppressing power consumption when shooting at a frame rate higher than the normal frame rate. Attached Figure Description

[0014] Figure 1This is a diagram showing the appearance of the imaging device according to this embodiment.

[0015] Figure 2 This diagram shows the main hardware components of the shooting device.

[0016] Figure 3 It is a diagram illustrating the pixel arrangement of the imaging element.

[0017] Figure 4 It is a diagram illustrating the composition of pixels.

[0018] Figure 5 This diagram illustrates the read control unit's control over the read of pixel signals.

[0019] Figure 6 This diagram illustrates the settings for the first and second pixels.

[0020] Figure 7 This is a diagram illustrating the window width used to generate the phase waveform.

[0021] Figure 8 This is a flowchart illustrating the processing procedure of the system control unit. Detailed Implementation

[0022] The present invention will now be described through embodiments thereof; however, the invention as defined by the claims is not limited to these embodiments. Furthermore, not all configurations described in the embodiments are necessary means to solve the problem. Additionally, in the figures, where multiple structures with the same or identical configurations exist, to avoid complexity, sometimes only some are labeled with reference numerals while others are omitted.

[0023] Figure 1 This is a diagram showing the appearance of the imaging device 100 according to this embodiment. In particular, Figure 1 (A) is a view mainly showing the first side of the imaging device 100. Figure 1 (B) is a diagram mainly showing the second side opposite to the first side. The shooting device 100 according to this embodiment is a smartphone, in other words, a smartphone that also functions as a shooting device. Hereinafter, the shooting function related to this invention among the functions of a smartphone will be described, omitting descriptions of other smartphone functions such as the utilization of image data generated by shooting. Furthermore, in this embodiment, a smartphone is used as an example to describe the shooting device 100, but it could of course be a shooting device with a single camera, or a device embedded in a tablet terminal or the like that has shooting capabilities.

[0024] The shooting device 100 includes a first camera unit 110 and a second camera unit 120 arranged in the same direction on a first side. The first camera unit 110 is a camera unit for generating wide-angle images. The second camera unit 120 is a camera unit for generating telephoto images. The user specifies the first camera unit to take a picture when a wide-angle image is desired, and specifies the second camera unit to take a picture when a telephoto image is desired. The first camera unit 110 and the second camera unit 120 are arranged parallel to the long side of the shooting device 100 in the figure, but the arrangement of the two camera units is not limited to this; for example, they can also be arranged along a straight line obliquely intersecting the long side. In addition, the arrangement of the first camera unit 110 and the second camera unit 120 can be reversed from the position shown in the figure.

[0025] The shooting device 100 includes a display 130 on its second side. The display 130 is, for example, a display device using an organic EL (Electroluminescence) panel, which displays a live image of the subject before shooting (live view display), or displays a live image during video recording (storage and browsing display), or displays an image after shooting. Furthermore, a self-portrait camera unit, independent of the first camera unit 110 and the second camera unit 120, can be provided on the second side.

[0026] A touch panel 162 is superimposed on the display 130. Users can tap the shutter button displayed on the display 130 to instruct the shooting device 100 to capture a still image, and tap the video recording button to instruct the shooting device 100 to start and stop video recording. Additionally, users can tap any part of the subject image displayed in live view or storage view to designate a specific area containing that part as the focus area. Furthermore, users can switch between the first camera unit 110 and the second camera unit 120, or select displayed menu items, through tapping or other contact actions.

[0027] Figure 2 This diagram illustrates the main hardware configuration of the shooting device 100. In addition to the first camera unit 110, the second camera unit 120, and the display 130 described above, the shooting device 100 also includes a system control unit 150 that controls them, and peripheral components that cooperate with the system control unit 150.

[0028] As described above, the first camera unit 110 is a camera unit for generating wide-angle images, and mainly includes a first optical system 111, a first drive mechanism 112, a first imaging element 113, and a first analog front-end (AFE) 114. The first optical system 111 is an optical system that images an incident subject beam onto the imaging surface of the first imaging element 113. Although represented by a single lens in this figure, it is generally composed of multiple lenses, at least some of which are focusing lenses capable of moving forward and backward along the optical axis. The first drive mechanism 112 is a drive mechanism for moving the focusing lens of the first optical system 111 along the optical axis, and includes an actuator that operates according to the instructions of the system control unit 150.

[0029] The first imaging element 113 is, for example, a CMOS image sensor. The first imaging element 113 will be described in detail later. Under the control of the system control unit 150 and the first AFE 114, the first imaging element 113 transmits an output signal to the first AFE 114. In addition to performing the AD conversion control described later, the first AFE 114 adjusts the readout timing of the output signal and adjusts the level according to a specified gain. The pixel signal adjusted by the first AFE 114 is transmitted to the working memory 151.

[0030] As described above, the second camera unit 120 is a camera unit for generating telephoto images, and mainly includes a second optical system 121, a second drive mechanism 122, a second imaging element 123, and a second analog front-end (AFE) 124. The second optical system 121 is an optical system for imaging an incident subject beam onto the imaging surface of the second imaging element 123. Although represented by a single lens in the figure, the second optical system 121, like the first optical system 111, is generally composed of multiple lenses, at least a portion of which is a focusing lens that can move back and forth along the optical axis. The second drive mechanism 122 is a drive mechanism for moving the focusing lens of the second optical system 121 along the optical axis, and includes an actuator that operates according to the instructions of the system control unit 150.

[0031] The second imaging element 123 is, for example, a CMOS image sensor. The second imaging element 123 will be described in detail below along with the first imaging element 113. The second imaging element 123 transmits an output signal to the second AFE 114 under the control of the system control unit 150 and the second AFE 124. In addition to performing the AD conversion control described later, the second AFE 124 adjusts the readout timing of the output signal or performs level adjustment according to a specified gain. The pixel signal adjusted by the second AFE 124 is transmitted to the working memory 151. Furthermore, in this embodiment, both the first optical system 111 and the second optical system 121 are assumed to be single-focus optical systems with a fixed focal length, but at least one of them may be a variable-focus optical system (zoom lens) capable of changing the focal length.

[0032] The system control unit 150 is a processor (CPU) that directly or indirectly controls the various elements constituting the imaging device 100. Depending on the control method to be executed, the system control unit 150 functions as a control unit for various functions. For example, when performing autofocus control of the first camera unit 110 and the second camera unit 120, the system control unit 150 functions as a detection unit that detects the phase difference of the subject image; when displaying the captured image on the display 130, it functions as a display control unit. In particular, in this embodiment, it functions as a readout control unit that reads signals output from the first imaging element 113 and the second imaging element 123 and generates pixel signals. Specific control of the readout control unit will be explained later.

[0033] The imaging device 100 mainly includes a working memory 151, an image processing unit 152, an operation unit 160, a storage unit 170, and a communication interface 180, serving as peripheral elements that cooperate with the system control unit 150. The working memory 151 is a volatile high-speed memory, for example, composed of SRAM (Static Random Access Memory). The working memory 151 receives individually converted pixel signals from the first AFE 114 and the second AFE 124, and stores them as frame data of one frame size. Additionally, it extracts designated pixel signals as phase difference signals, generates and stores phase waveform data for defocus calculation in autofocus (AF). The working memory 151 transmits frame data to the image processing unit 153 and phase waveform data to the system control unit 150. Furthermore, the working memory 151 is also appropriately used as a temporary storage area during image processing stages in the image processing unit 153 or during focus processing stages in the system control unit 150.

[0034] The image processing unit 153 is, for example, composed of an ASIC (Application Specific Integrated Circuit) specifically designed for image processing. It performs various image processing operations, such as interpolation, on the received frame data to generate image data conforming to a predetermined format. If the generated image data is for storage, it is stored in the storage unit 170; if it is for display, it is displayed on the display 130.

[0035] The operation unit 160 is an input device including a touch panel 162, and is a component operated when the user provides instructions to the shooting device 100. When the shooting device 100 accepts voice input, a microphone may also be included in the operation unit 160. The storage unit 170 is a non-volatile memory, such as an SSD (Solid State Drive). In addition to storing image data generated by the shooting, the storage unit 170 also stores constants, variables, settings, and control programs required for the operation of the shooting device 100. The communication interface 180 may include a 5G line or a wireless LAN communication unit. The communication interface 180 is used when transmitting generated image data to external devices, etc.

[0036] Next, the structure of the imaging element and the readout control of the pixel signal will be explained. In this embodiment, the first imaging element 113 and the second imaging element 123 are imaging elements with the same structure, and the first AFE 114 and the second AFE 124 perform the same readout control on these imaging elements. Therefore, assuming that the first camera unit 110 is capturing video images, the structure of the first imaging element 113 (hereinafter referred to as "imaging element 113") and the readout control by the system control unit 150 (readout control unit) of the first AFE 114 (hereinafter referred to as "AFE 114") will be explained.

[0037] Figure 3 This diagram illustrates the pixel arrangement of the imaging element 113. In the imaging element 113, each pixel 200 includes a first photoelectric conversion unit 201 and a second photoelectric conversion unit 202, and each pixel 200 is composed of a pixel plane formed by multiple pixels arranged in a two-dimensional manner. The first photoelectric conversion unit 201 and the second photoelectric conversion unit 202 individually form a roughly rectangular shape that roughly bisects the square pixel area. Relative to the center of the pixel 200, the first photoelectric conversion unit 201 is offset in a first direction (left side in the diagram), and the second photoelectric conversion unit 202 is offset in a second direction opposite to the first direction (right side in the diagram).

[0038] It should be understood that in some possible embodiments, each pixel 200 may include more than two photoelectric conversion units, such as four, and the four photoelectric conversion units may be arranged in a 2x2 configuration.

[0039] Figure 4 This is a diagram illustrating the configuration of pixel 200, and schematically showing a cross-section of the first optical system 111 (hereinafter referred to as "optical system 111"), a cross-section of pixel 200, and a portion of the circuitry of AFE 114.

[0040] The first photoelectric conversion unit 201 receives a light beam passing through a first partial region PA1 of the optical system 111, which serves as an imaging optical system. The second photoelectric conversion unit 202 receives a light beam passing through a second partial region PA2, which is different from the first partial region PA1 of the optical system 111. The first partial region PA1 and the second partial region PA2 may also have non-overlapping areas. All light beams reach their respective photoelectric conversion units via a microlens 211 and a color filter 212 disposed above the pixel.

[0041] When the first switch 221 is closed, the AD converter 230 converts the charge accumulated in the first photoelectric conversion unit 201 into a digital signal and outputs it as a pixel signal. When the second switch 222 is closed, the charge accumulated in the second photoelectric conversion unit 202 is converted into a digital signal by the AD converter 230 and output as a pixel signal.

[0042] Figure 5 This diagram illustrates the read control of pixel signals performed by the read control unit. The read control unit can generate pixel signals by performing either individual read control or unified read control on pixels 200 that are in a charge accumulation state.

[0043] Figure 5 (A) is a diagram illustrating the separate control reading process. In separate control reading, firstly, as... Figure 5 As shown in Figure (A) above, the read control unit closes the first switch 221 and keeps the second switch 222 open, so that the AD converter 230 performs AD conversion only on the charge accumulated in the first photoelectric conversion unit 201 and outputs pixel signal A. At this time, the charge accumulated in the second photoelectric conversion unit 202 remains unchanged. Next, as... Figure 5 As shown in Figure (A) below, the read control unit closes the second switch 222 and opens the first switch 221, so that the AD converter 230 performs AD conversion only on the charge accumulated in the second photoelectric conversion unit 202 and outputs pixel signal B. In this way, by repeating the AD conversion twice, pixel signal A corresponding to the charge of the first photoelectric conversion unit 201 and pixel signal B corresponding to the charge of the second photoelectric conversion unit 202 can be output sequentially. Since pixel signal A and pixel signal B are both generated from the same pixel, they are collectively referred to here as the first pixel signal. Furthermore, the order in which pixel signal A and pixel signal B are generated can also be reversed.

[0044] Figure 5(B) is a diagram illustrating unified readout control. In unified readout control, the readout control unit 221 and the second switch 222 are closed together, and the charge accumulated in the first photoelectric conversion unit 201 and the charge accumulated in the second photoelectric conversion unit 202 are added together. The AD converter 230 performs AD conversion and outputs the second pixel signal. In this way, through one AD conversion, the second pixel signal corresponding to the charge obtained by adding the charges of the first photoelectric conversion unit 201 and the second photoelectric conversion unit 202 can be output.

[0045] When a normal shooting mode based on a typical frame rate (e.g., 30fps or 60fps) is selected, the readout control unit performs a first readout control that applies individual readout control to all pixels. In this case, if the pixel value of pixel signal A, which serves as the first pixel signal, is added to the pixel value of that pixel in the frame data, the result is the pixel value. Furthermore, if the pixel signals A and B of each pixel group corresponding to a specified subject image specified by the user or selected by an automatic algorithm are individually combined, phase waveform data for that specified subject image can be generated. That is, if the first pixel signal is generated from all pixels, dense phase waveform data can be generated for any subject, maintaining focus with high precision even for subjects moving during shooting.

[0046] On the other hand, if the first readout control is attempted at a higher frame rate than usual (e.g., 120fps or 240fps), two A / D conversions are required for all pixel counts, resulting in a significant increase in power consumption. This increased power consumption not only shortens the operating time of the shooting device but can also sometimes cause instability due to the generated heat. Furthermore, the processing time required for the two A / D conversions and the processing time for the large first pixel signal generated may not be controlled within the frame rate cycle. That is, sometimes readout processing and data processing cannot keep up with the high frame rate. If this situation occurs, not only will the subject not be able to maintain focus, but a frame image may also fail to be generated.

[0047] Therefore, in this embodiment, when a shooting mode with a high frame rate is selected, a second read control that combines individual read control and unified read control is executed. Examples of shooting modes with a high frame rate include high frame mode (slow motion mode), which allows for playback at the normal frame rate, providing a smoother and slower-moving image of the subject than it actually is.

[0048] During the second read control, all effective pixels of the imaging element 111 are pre-configured to be assigned to a first pixel for which individual read control is applied and a second pixel for which unified read control is applied. Figure 6 This diagram illustrates the settings of the first and second pixels under the condition of performing the second read control. In this diagram, the pixel surrounded by the thick frame is set as the first pixel 200a, while the other pixels are set as the second pixel 200b.

[0049] In the example shown, the first pixel 200a is periodically set according to a ratio of 5 pixels vertically × 5 pixels horizontally. By surrounding and discretely configuring the first pixel 200a with the second pixel 200b, the number of first pixels 200a requiring separate readout control can be significantly reduced. By significantly reducing the number of first pixels 200a, overall power consumption can be reduced. Furthermore, since the amount of generated pixel signal can also be suppressed, the processing time required can be shortened, allowing AF processing and frame image generation to continue appropriately even at high frame rates.

[0050] However, the phase waveform data used for AF processing is obtained only from the discretely configured first pixel 200a, so a balance must be considered with the reduction in focusing accuracy. That is, the ratio of the first pixel 200a to the second pixel 200b is determined by balancing the advantages of power saving and high-speed processing with the disadvantage of reduced focusing accuracy. For example, when the user can select multiple frame rates, the higher the frame rate, the more adjustments can be made, such as reducing the ratio of the first pixel 200a to the second pixel 200b.

[0051] It should be understood that the discrete configuration of the first pixel 200a used for AF processing can be configured in various ways. For example, it can be set evenly in a certain proportion, that is, the first pixel 200a is evenly distributed among all pixels in a certain proportion, which can maintain the overall focusing performance evenly. Alternatively, the first pixel 200a can be set denser in the central area of ​​the image and sparser in the edge area. This center-priority setting can be set for portrait mode or specific emphasis modes, which can provide better focusing performance in the center of the image.

[0052] In addition, even with a limited number of first pixels 200a, the window width used to generate the phase waveform can be adjusted to improve focusing accuracy. Figure 7 This is a diagram illustrating the window width used to illustrate the generation of the phase waveform.

[0053] Figure 7(A) shows the first window width set when applying individual readout control to all pixels 200 and performing the first readout control. The first window width is set to W1 pixels, and when the first readout control is performed, the detection unit generates a phase waveform by using pixel signals A and B generated by these pixels 200, and performs phase difference detection on the subject image to focus.

[0054] Figure 7 (B) indicates the second window width set when performing a second read control that combines individual read control and unified read control. The second window width is set to be W2 pixels more than W1 pixels. When performing the second read control, the detection unit uses pixel signals A and B generated by the first pixel 200a, which is the object of individual read control, from the pixels 200 included in the second window width to generate a phase waveform and performs phase difference detection on the subject image.

[0055] That is, when performing the second readout control, if the first window width is set to the same as when performing the first readout control, the generated phase waveform becomes shorter. By setting a second window width larger than the first window width, the length of the generated phase waveform increases, which can compensate for the decrease in phase difference detection accuracy. However, as the window width increases, the possibility of capturing multiple subjects also increases accordingly, which can easily cause near-far collisions. Therefore, the window width can be appropriately enlarged according to the ratio of the first pixel 200a to the second pixel 200b.

[0056] Next, the processing procedure of the system control unit 150 in a series of video shooting and processing will be explained. Figure 8 This is a flowchart illustrating the processing procedure of the system control unit 150.

[0057] In step S101, the system control unit 150 receives a selection from the user: a first mode with a normal frame rate and a second mode with a frame rate higher than the normal frame rate. The system control unit 150 switches to the selected shooting mode, and in step S102, waits for an instruction from the user to start shooting. If an instruction to start shooting is received, the process proceeds to step S103, where the current shooting mode is confirmed. If it is the first mode (normal frame rate), the process proceeds to step S104; if it is the second mode (high-speed frame rate), the process proceeds to step S108.

[0058] When the process progresses from step S103 to step S104, the system control unit 150, acting as a read control unit, performs first read control. In the next step S105, as a detection unit, the system control unit 150 generates a phase waveform based on a first window width set in the pixel group corresponding to the specified subject image, performs phase difference detection, and executes AF processing. In the next step S106, the system control unit 150 generates one frame of frame data according to the set normal frame rate. In step S107, the system control unit 150 checks whether a shooting stop instruction has been received from the user. If no shooting stop instruction is received, the process returns to step S104 and continues video recording. When a shooting stop instruction is received, the previously accumulated frame data is processed according to the set format to generate a video file, ending the series of processes.

[0059] When proceeding from step S103 to step S108, the system control unit 150, acting as a read control unit, performs second read control. In the next step S109, the system control unit 150, acting as a detection unit, generates a phase waveform based on the second window width set in the pixel group corresponding to the specified subject image, and performs AF processing by performing phase difference detection. In the next step S110, the system control unit 150 generates one frame of frame data according to the set high-speed frame rate. In step S111, the system control unit 150 checks whether it has received a shooting stop instruction from the user. If no shooting stop instruction is received, it returns to step S108 and continues video recording; if a shooting stop instruction is received, it performs the set formatting processing on the previously accumulated frame data, generates a video file, and ends the series of processes.

[0060] In the embodiment described above, the case of capturing video images is assumed, but the same focus control can also be performed when capturing still images. That is, when a still image can be obtained each time the shutter button is pressed, or when a shooting mode that captures continuous images at a low speed is selected, a first read control with separate read control is applied to all pixels 200, and a second read control that combines separate read control and unified read control is applied when a shooting mode that captures continuous images at a high speed is selected.

[0061] In one possible implementation, more than two shooting modes can be set based on different frame rates or continuous shooting speeds, each corresponding to a different level of focus precision. For example, a higher frame rate / faster continuous shooting speed results in fewer pixels involved in focusing, allowing for a more flexible balance between power consumption and performance.

[0062] Explanation of reference numerals in the attached figures:

[0063] 100…Shooting device, 110…First camera unit, 111…First optical system (optical system), 112…First drive mechanism (drive mechanism), 113…First shooting element (shooting element), 114…First analog front end (AFE), 120…Second camera unit, 121…Second optical system, 122…Second drive mechanism, 123…Second shooting element, 124…Second analog front end, 130…Display, 150…System control unit, 151…Working memory, 152…Image processing unit, 160…Operation unit, 162…Touch panel, 170…Storage unit, 180…Communication interface, 200…Pixel, 200a…First pixel, 200b…Second pixel, 201…First photoelectric conversion unit, 202…Second photoelectric conversion unit, 210…Microlens, 212…Color filter, 221…First switch, 222…Second switch, 230…AD converter.

Claims

1. A shooting device, characterized in that, have: The imaging element has multiple pixels arranged in a two-dimensional pattern. Each pixel includes at least a first photoelectric conversion unit and a second photoelectric conversion unit. The first photoelectric conversion unit receives a light beam passing through a first partial region of the imaging optical system, and the second photoelectric conversion unit receives a light beam passing through a second partial region that is different from the first partial region. The read control unit performs a first read control in a first mode and a second read control in a second mode where the frame rate is set to a higher frame rate than that set in the first mode. The first read control causes the charges of the first photoelectric conversion unit and the second photoelectric conversion unit to be individually converted by an analog-to-digital converter (AD) to generate a pixel signal. The second read control causes the charges of the first photoelectric conversion unit and the second photoelectric conversion unit to be individually converted by an AD to generate a first pixel signal in a discretely set first pixel among the pixels. In a second pixel among the pixels that is not the first pixel, the charges of the first photoelectric conversion unit and the second photoelectric conversion unit are added together and then converted by an AD to generate a second pixel signal. as well as The detection unit uses pixel signals obtained by separately performing AD conversion on the charges of the first and second photoelectric conversion units to perform phase difference detection and focusing. When the reading control unit performs the second reading control, the width of the window used to generate the phase waveform is larger than when the first reading control is performed.

2. A reading control method, characterized in that, include: Pixel signals are read from an imaging element, which has multiple pixels arranged in a two-dimensional pattern. Each pixel includes a first photoelectric conversion unit and a second photoelectric conversion unit. The first photoelectric conversion unit receives a light beam passing through a first portion of the imaging optical system, and the second photoelectric conversion unit receives a light beam passing through a second portion of the imaging optical system, which is different from the first portion. A mode is determined from a first mode and a second mode in which the frame rate is set higher than that set in the first mode; In a first mode, a first readout control is performed; in a second mode, a second readout control is performed. The first readout control causes the charges of the first and second photoelectric conversion units to undergo individual AD conversion to generate pixel signals. The second readout control, in discretely set first pixels, causes the charges of the first and second photoelectric conversion units to undergo individual AD conversion to generate first pixel signals; and in second pixels that are not the first pixels, the charges of the first and second photoelectric conversion units are added together and then AD converted to generate second pixel signals. Phase difference detection focusing is performed using pixel signals obtained by separately performing AD conversion on the charges of the first and second photoelectric conversion units. In this case, the width of the window used to generate the phase waveform during the second read control is larger than that during the first read control.

Images