IMAGING APPARATUS, IMAGING CONTROL METHOD, AND IMAGING CONTROL PROGRAM
By allocating different exposure times on the image sensor, the problem of poor exposure time management in the prior art when image shooting and focus detection are performed simultaneously is solved, and the balance between image quality and focus detection accuracy is achieved.
Patent Information
- Application Number
- JP2021162017
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-09-30
- Publication Date
- 2025-04-03
- Estimated Expiration
- 2041-09-30
AI Technical Summary
When performing image shooting and focus detection at the same time, it is difficult to effectively manage the exposure time of different pixel areas, resulting in poor image quality and focus detection accuracy.
Image sensors including focus detection pixels and ordinary pixels are used to capture images by allocating different exposure times. The exposure time of the focus detection pixel area is set to a long to ensure that sufficient light is used for focus detection, and the exposure time of the ordinary pixel area is set to a short to meet the needs of real-time image shooting.
It realizes the balance between image quality and focus detection accuracy in continuous shooting mode, ensuring real-time image updates and high accuracy of focus detection.
Smart Images

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Abstract
Description
[Technical field]
[0001] The present invention relates to an imaging device, an imaging control method, and an imaging control program. [Background technology]
[0002] Patent document 1 describes a solid-state imaging device that sequentially and cyclically repeats two or more readout modes for each frame, including a live view readout mode that reads out imaging signals for live view display, and a focus detection / auto exposure readout mode that reads out imaging signals to be used for focus detection signals and auto exposure metering information from a solid-state imaging element.
[0003] Patent Document 2 describes an imaging device having an image sensor with rows including focus detection pixels and rows including imaging pixels not including focus detection pixels. Based on the photometry result by a photometry means, this imaging device calculates a first charge accumulation time for the imaging pixels and a second charge accumulation time longer than the first charge accumulation time for the focus detection pixels, drives the rows not including focus detection pixels for the first charge accumulation time and the rows including focus detection pixels for the second charge accumulation time, periodically updates and displays image signals obtained from the imaging pixels of the rows driven for the first charge accumulation time, and performs focus detection processing using a phase difference method based on image signals obtained from the focus detection pixels of the rows driven for the second charge accumulation time.
[0004] Patent document 3 describes an imaging device that includes a switching unit that switches between a full pixel readout mode, in which signals from all pixels of a plurality of pixels are read out, and a thinning-out readout mode, in which signals from a plurality of pixels are thinned out and read out, and a control unit that, when switched to the thinning-out readout mode by the switching unit, independently controls the accumulation of charge in an imaging row used for image generation and in a focus detection row having focus detection pixels. [Prior art documents] [Patent documents]
[0005] [Patent Document 1] JP 2009-089105 A [Patent Document 2] JP 2015-068959 A [Patent Document 3] JP 2010-219958 A Summary of the Invention [Means for solving the problem]
[0006] An imaging device according to one embodiment of the technology disclosed herein comprises an imaging element including a first light receiving region in which a pixel group including focus detection pixels is arranged, and a second light receiving region in which a pixel group not including the focus detection pixels is arranged, and a processor, wherein the processor performs first control to cause the imaging element to capture an image at a first exposure time, and second control to cause the imaging element to capture an image with an exposure time of the second light receiving region as the first exposure time and an exposure time of the first light receiving region as a second exposure time.
[0007] An imaging control method according to one embodiment of the technology disclosed herein is an imaging control method for controlling an imaging element including a first light receiving region in which a pixel group including focus detection pixels is arranged, and a second light receiving region in which a pixel group not including the focus detection pixels is arranged, and performs a first control for causing the imaging element to capture an image at a first exposure time, and a second control for causing the imaging element to capture an image with an exposure time of the second light receiving region as the first exposure time and an exposure time of the first light receiving region as a second exposure time.
[0008] An imaging control program of one embodiment of the technology disclosed herein is an imaging control program that controls an imaging element including a first light receiving area in which a pixel group including focus detection pixels is arranged, and a second light receiving area in which a pixel group not including the focus detection pixels is arranged, and causes a processor to perform first control to cause the imaging element to capture an image at a first exposure time, and second control to cause the imaging element to capture an image with an exposure time of the second light receiving area as the first exposure time and an exposure time of the first light receiving area as a second exposure time. [Brief description of the drawings]
[0009] [Figure 1] 1 is a diagram showing a schematic configuration of a digital camera 100 which is an embodiment of an imaging apparatus of the present invention. [Diagram 2] 2 is a plan view showing a schematic configuration of the imaging element 5 shown in FIG. [Diagram 3] FIG. 13 is a diagram showing an example of a curve indicating a correlation calculation result. [Figure 4] 2 is a diagram showing an example of a timing chart for explaining the operation of digital camera 100 shown in FIG. 1 in a continuous shooting mode. [Diagram 5] 11 is a timing chart for explaining a first modified example of the operation of the digital camera 100. [Figure 6] 10 is a timing chart for explaining a second modified example of the operation of the digital camera 100. [Figure 7] FIG. 13 is a diagram showing an example of a program diagram used when exposing a pixel line 63. [Figure 8] FIG. 13 is a diagram showing an example of a program diagram used when exposing a pixel line 63. [Figure 9] 2 shows the external appearance of a smartphone 200. [Figure 10] 10 is a block diagram showing a configuration of the smartphone 200 shown in FIG. 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] FIG. 1 is a diagram showing a schematic configuration of a digital camera 100 which is an embodiment of an imaging apparatus of the present invention.
[0011] 1 includes a lens device 40 having an imaging lens 1, an aperture 2, a lens control unit 4, a lens driving unit 8, and an aperture driving unit 9, and a main body unit 100A. The main body unit 100A includes an imaging unit 50, a system control unit 11, an operation unit 14, a display device 22, a memory 16 including a RAM (Random Access Memory) and a ROM (Read only memory) and the like, a memory control unit 15 that controls data recording to the memory 16 and data reading from the memory 16, a digital signal processing unit 17, and an external memory control unit 20 that controls data recording to a recording medium 21 and data reading from the recording medium 21.
[0012] The lens device 40 may be detachable from the main body 100A, or may be integrated with the main body 100A. The imaging lens 1 includes a focus lens that is movable in the optical axis direction. This focus lens is a lens for adjusting the focus of an imaging optical system that includes the imaging lens 1 and the aperture 2, and is composed of a single lens or multiple lenses. When the focus lens moves in the optical axis direction, the position of the principal point of the focus lens changes along the optical axis direction, and the focal position on the subject side is changed. Note that the focus lens may be a liquid lens whose principal point in the optical axis direction can be changed by electrical control.
[0013] The lens control unit 4 of the lens device 40 is configured to be able to communicate with the system control unit 11 of the main body unit 100A by wire or wirelessly. In accordance with a command from the system control unit 11, the lens control unit 4 controls the focus lens included in the imaging lens 1 via the lens driving unit 8 to change the position of the principal point of the focus lens, and controls the aperture value of the aperture 2 via the aperture driving unit 9.
[0014] The imaging section 50 includes an imaging element 5 that captures an image of a subject through an imaging optical system including an imaging lens 1 and an aperture 2, and an imaging element driving section 10 that drives the imaging element 5.
[0015] The imaging element 5 has an imaging surface 60 (see FIG. 2) on which a plurality of pixels 61 are arranged two-dimensionally, and converts a subject image formed on the imaging surface 60 by an imaging optical system into pixel signals by the plurality of pixels 61 and outputs the pixel signals. A complementary metal-oxide semiconductor (CMOS) image sensor is preferably used as the imaging element 5. In the following description, it is assumed that the imaging element 5 is a CMOS image sensor.
[0016] A system control unit 11, which controls the entire electrical control system of the digital camera 100, drives the image sensor 5 via the image sensor drive unit 10, and outputs the subject image captured through the imaging optical system of the lens device 40 as an image signal.
[0017] The image sensor driver 10 generates a drive signal based on a command from the system controller 11 and supplies the drive signal to the image sensor 5, thereby driving the image sensor 5. The hardware configuration of the image sensor driver 10 is an electric circuit formed by combining circuit elements such as semiconductor elements.
[0018] An instruction signal from a user is input to the system control unit 11 through the operation unit 14. The operation unit 14 includes a touch panel integrated with a display surface 22b (to be described later), various buttons, and the like.
[0019] The system control unit 11 controls the entire digital camera 100, and its hardware structure is various processors that execute programs including an imaging control program and perform processing. The programs executed by the system control unit 11 are stored in the ROM of the memory 16.
[0020] The various processors include a CPU (Central Processing Unit), which is a general-purpose processor that executes programs to perform various processes, a Programmable Logic Device (PLD), which is a processor whose circuit configuration can be changed after manufacture, such as an FPGA (Field Programmable Gate Array), or a dedicated electric circuit, such as an ASIC (Application Specific Integrated Circuit), which is a processor having a circuit configuration designed exclusively for executing a specific process. More specifically, the structure of these various processors is an electric circuit that combines circuit elements such as semiconductor elements.
[0021] The system control unit 11 may be configured with one of various processors, or may be configured with a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs or a combination of a CPU and an FPGA).
[0022] The display device 22 includes a display surface 22b configured with an organic EL (electroluminescence) panel, a liquid crystal panel, or the like, and a display controller 22a that controls the display on the display surface 22b.
[0023] The memory control unit 15 , the digital signal processing unit 17 , the external memory control unit 20 , and the display controller 22 a are interconnected by a control bus 24 and a data bus 25 , and are controlled by commands from the system control unit 11 .
[0024] Fig. 2 is a plan schematic diagram showing a schematic configuration of the image sensor 5 shown in Fig. 1. The image sensor 5 has an image sensor surface 60 on which a plurality of pixels 61 are two-dimensionally arranged in a row direction X and a column direction Y perpendicular to the row direction X. The plurality of pixels 61 include a focus detection pixel 61b that receives one of a pair of light beams that have passed through two different portions aligned in the row direction X of a pupil region of the image pickup optical system and detects a signal corresponding to the amount of received light, a focus detection pixel 61c that receives the other of the pair of light beams and detects a signal corresponding to the amount of received light, and a normal pixel 61a that receives both of the pair of light beams and detects a signal corresponding to the amount of received light.
[0025] In the example of FIG. 2, pixel lines 62 each including a plurality of normal pixels 61a arranged in the row direction X and pixel lines 63 each including a plurality of focus detection pixels 61b and focus detection pixels 61c arranged alternately in the row direction X are arranged alternately in the column direction Y on the imaging surface 60. The pixel line 63 may include a plurality of pairs of focus detection pixels 61b and focus detection pixels 61c, and may include normal pixels 61a in addition to the pairs. Hereinafter, the pixel lines 62 and pixel lines 63 are also simply referred to as pixel lines when there is no need to distinguish between them. The imaging element 5 further includes a drive circuit 64 that drives the pixels 61 arranged on the imaging surface 60, and a signal processing circuit 65 that processes pixel signals read out to signal lines from the pixels 61 of each pixel line arranged on the imaging surface 60.
[0026] 2, one end of imaging surface 60 in the column direction Y (upper side in the figure) is referred to as the upper end, and the other end of imaging surface 60 in the column direction Y (lower side in the figure) is referred to as the lower end. The region on imaging surface 60 where each pixel line 63 is arranged constitutes a first light receiving region. The region on imaging surface 60 where each pixel line 62 is arranged constitutes a second light receiving region.
[0027] The drive circuit 64 drives each pixel line independently based on a signal from the image sensor drive unit 10, and resets each pixel 61 included in each pixel line (discharging the charge accumulated in the photoelectric conversion element), and reads out pixel signals corresponding to the charge accumulated in the photoelectric conversion element of each pixel 61 to a signal line.
[0028] The signal processing circuit 65 performs correlated double sampling on the pixel signals read out from each pixel 61 in the pixel line to the signal line, converts the pixel signals after the correlated double sampling into digital signals, and outputs them to the data bus 25 (see FIG. 1). The signal processing circuit 65 is controlled by the image sensor driving unit 10.
[0029] The digital signal processor 17 performs signal processing such as demosaic processing and gamma correction processing on the pixel signals output from the imaging element 5 to the data bus 25 to generate captured image data.
[0030] The digital camera 100 is equipped with a continuous shooting mode in which a plurality of captured image data sets are generated in succession in response to a single image capture instruction and recorded on the recording medium 21.
[0031] In the continuous shooting mode, the system control unit 11 drives the image sensor 5 by the image sensor driving unit 10 using the rolling shutter method to capture an image of a subject. The rolling shutter method driving includes rolling reset driving and rolling read driving. The rolling reset driving is a driving method in which a process of resetting each pixel 61 in a pixel line and starting exposure of each pixel 61 is performed sequentially while changing pixel lines. The rolling read driving is a driving method in which a process of reading a signal from each pixel 61 in an exposed pixel line and ending exposure of the pixel line is performed sequentially while changing pixel lines.
[0032] In the continuous shooting mode, when the system control unit 11 receives an imaging instruction, it continuously performs recording imaging control for recording captured image data, displaying a live view image on the display surface 22b, and causing the image sensor 5 to output pixel signals for use in focus detection. In addition, between each of the multiple recording imaging controls, the system control unit 11 performs display imaging control at least once for displaying a live view image on the display surface 22b and causing the image sensor 5 to output pixel signals for use in focus detection. The recording imaging control constitutes a first control, and the display imaging control constitutes a second control.
[0033] Focus detection refers to a process of performing a correlation calculation between a first group of pixel signals output from each focus detection pixel 61b included in the same pixel line 63 and a second group of pixel signals output from each focus detection pixel 61c, and deriving the amount of drive of the focus lens required to focus on the target subject based on the result of the correlation calculation.
[0034] Correlation calculation is a process in which the area S[d] enclosed by two data waveforms consisting of a first pixel signal group and a data waveform consisting of a second pixel signal group is shifted by an amount d, and the shift amount d is changed among multiple values.
[0035] FIG. 3 is a diagram showing an example of a curve showing a correlation calculation result. The horizontal axis of FIG. 3 indicates the shift amount d, and the vertical axis of FIG. 3 indicates the area S[d]. The drive amount of the focus lens can be derived by deriving the defocus amount based on the shift amount d=d1 when the area S[d] becomes the minimum value min. The maximum value max of the area S[d] depends on the target subject. For example, if the subject has high contrast (≒ bright conditions), the maximum value max becomes large, and if the subject has low contrast (≒ dark conditions), the maximum value max becomes small. If the difference between the maximum value max and the minimum value min becomes small, it becomes difficult to determine the minimum value min, so the magnitude of this maximum value max affects the derivation accuracy of the drive amount of the focus lens (in other words, the focus detection accuracy).
[0036] In the recording imaging control, the system control unit 11 causes the imaging element 5 to capture an image with the exposure time of the pixel line 62 and the pixel line 63 set as a first exposure time (exposure time EX1 described later). The first exposure time is a value determined based on the exposure set by the user or the exposure automatically set depending on the brightness of the subject, etc.
[0037] In the imaging control for display, the system control unit 11 controls the imaging element 5 to capture an image with the exposure time of the pixel line 62 set to the above-mentioned first exposure time and the exposure time of the pixel line 63 set to the second exposure time (exposure time EX2 described later). The second exposure time is a value determined by exposure conditions that can sufficiently ensure the detection accuracy of the minimum value min described above, and may be the same as the first exposure time or may be a value greater than the first exposure time. However, since the focus detection pixels 61b and 61c receive less light than the normal pixels 61a, the second exposure time is almost always longer than the first exposure time.
[0038] FIG. 4 is a diagram showing an example of a timing chart for explaining the operation of digital camera 100 shown in FIG. 1 in the continuous shooting mode.
[0039] The upper part of FIG. 4 shows the drive timing of each pixel line of the image sensor 5. In the upper part of FIG. 4, the vertical axis indicates the position of the pixel line in the column direction Y. The solid diagonal line RR (only some of which are marked) shown in this drive timing indicates the timing at which exposure of each pixel line is completed by rolling read drive. The dashed diagonal line RS1 (only some of which are marked) shown in this drive timing indicates the timing at which each pixel line is reset (exposure starts). The dashed diagonal line RS2 (only some of which are marked) shown in this drive timing indicates the timing at which each pixel line 63 is reset (exposure starts). The dashed diagonal line RS3 (only some of which are marked) shown in this drive timing indicates the timing at which each pixel line 62 is reset (exposure starts). The period surrounded by the diagonal line RR and the diagonal line RR to the right of it constitutes one frame period as a control cycle. 4, a frame period during which imaging control for recording is performed is indicated as frame period 71, and a frame period during which imaging control for display is performed is indicated as frame period 72. In the example of Fig. 4, upon receiving an imaging instruction, the system control unit 11 repeatedly executes a process of performing imaging control for recording (frame period 71), imaging control for display (frame period 72), and imaging control for display (frame period 72) in this order.
[0040] In a frame period 71 during which image capture control for recording is performed, the period enclosed by the diagonal line RS1 and the adjacent diagonal line RR to the right of it indicates the exposure time EX1 of all pixel lines. A group of pixel signals output from each pixel 61 of the image sensor 5 by image capture during the exposure time EX1 in the frame period 71 is used for generating captured image data, generating a live view image, and for focus detection.
[0041] In a frame period 72 in which imaging control for display is performed, the period surrounded by the diagonal line RS2 and the diagonal line RR on the right side indicates the exposure time EX2 of the pixel line 63, and the period surrounded by the diagonal line RS3 and the diagonal line RR on the right side indicates the exposure time EX1 of the pixel line 62. As shown in FIG. 4, the exposure time EX2 is longer than the exposure time EX1. A group of pixel signals output from each pixel line 63 by imaging during the exposure time EX2 in the frame period 72 is used for focus detection. A group of pixel signals output from each pixel line 62 by imaging during the exposure time EX1 in the frame period 72 is used for generating a live view image.
[0042] The rectangle shown in the "Display Update" section of Fig. 4 indicates the period during which the live view image displayed on display surface 22b is updated. The rectangle shown in the "AF (Autofocus) Calculation" section of Fig. 4 indicates the period during which focus detection is performed. The rectangle shown in the "Predictive Calculation" section of Fig. 4 indicates the period during which processing is performed to predict the focus lens drive amount at the subsequent exposure start timing of the recording imaging control, based on the focus lens drive amount obtained in past focus detections up to that point. The rectangle shown in the "Focus Lens Drive" section of Fig. 4 indicates the period during which the focus lens is driven based on the results of the predictive calculation.
[0043] The system control unit 11 continues to execute image capture control for recording (however, the exposure time does not have to be EX1) until it receives an image capture instruction, and repeatedly performs display of a live view image, focus detection, and predictive calculation based on the pixel signal group obtained thereby. Then, when the system control unit 11 receives an image capture instruction, it drives the focus lens according to the drive amount at the start point of the first frame period 71 predicted at that time, and performs focus control (step S0 in FIG. 4).
[0044] After receiving the imaging instruction, the system control unit 11 executes recording imaging control in the first frame period 71. After finishing the recording imaging control, the system control unit 11 executes two display imaging controls in succession. The system control unit 11 also generates a live view image based on the pixel signal group of the pixel line 62 obtained in the recording imaging control, and displays this on the display surface 22b to update the display (step S2 in FIG. 4). The system control unit 11 also executes focus detection based on the pixel signal group of the pixel line 63 obtained in the recording imaging control (step S3 in FIG. 4), and predicts the focus lens drive amount at the start of exposure in the second frame period 71 based on the focus lens drive amount obtained thereby and the focus lens drive amount obtained in the past focus detection (step S4 in FIG. 4).
[0045] If the driving of the focus lens with the drive amount predicted in step S4 can be completed by the start of exposure in the second frame period 71, the system control unit 11 performs focusing control by driving the focus lens according to the predicted drive amount by the start of exposure in the second frame period 71. Note that Fig. 4 shows a case where the driving of the focus lens with the drive amount predicted in step S4 cannot be completed by the start of exposure in the second frame period 71. In such a case, when the first frame period 71 ends, the system control unit 11 drives the focus lens according to the drive amount at the start of exposure in the second frame period 71 that was predicted in step S1 during the first frame period 71 (step S5 in Fig. 4).
[0046] When the first frame period 72 after the imaging instruction ends, the system control unit 11 generates a live view image based on the pixel signals of pixel line 62 obtained by imaging during that frame period 72, and displays this on display surface 22b to update the display (step S6 in FIG. 4). Furthermore, when the first frame period 72 ends, the system control unit 11 executes focus detection based on the pixel signals of pixel line 63 obtained by imaging during that frame period 72 (step S7 in FIG. 4), and predicts the focus lens drive amount at the start of exposure for the third frame period 71 based on the focus lens drive amount obtained thereby and the focus lens drive amount obtained in the past focus detection (at least the drive amount calculated in step S3) (step S8 in FIG. 4).
[0047] When the second frame period 72 after the imaging instruction is completed, the system control unit 11 generates a live view image based on the pixel signal group of the pixel line 62 obtained by imaging during the frame period 72, and displays the live view image on the display surface 22b to update the display (step S9 in FIG. 4). When the second frame period 72 is completed, the system control unit 11 executes focus detection based on the pixel signal group of the pixel line 63 obtained by imaging during the frame period 72 (step S10 in FIG. 4), and predicts the focus lens drive amount at the start of exposure during the third frame period 71 based on the focus lens drive amount obtained by the focus lens drive amount obtained by the focus lens drive amount obtained by the past focus detection (including the drive amount obtained in steps S3 and S7) (step S11 in FIG. 4). Then, the system control unit 11 drives the focus lens according to the drive amount predicted in step S11 (step S12 in FIG. 4). Thereafter, the same operations as steps S2 to S12 are repeated.
[0048] As described above, according to the digital camera 100, imaging is performed with an exposure suitable for recording during the frame period 71, so that high-quality captured image data can be recorded. Furthermore, during the frame period 72, imaging is performed for the pixel line 62 with the same exposure time EX1 as the frame period 71, and the live view image is updated based on the pixel signals output from this pixel line 62. This allows the brightness of the live view image to be constant, and the quality of the live view image during continuous shooting can be improved. Furthermore, during the frame period 72, imaging is performed for the pixel line 63 with the exposure time EX2 suitable for focus detection, and focus detection is performed based on the pixel signals output from this pixel line 63. This allows the accuracy of focus control using the result of this focus detection to be improved.
[0049] (First Modification of the Operation of Digital Camera 100) 5 is a timing chart for explaining a first modified example of the operation of digital camera 100. This first modified example shows an example of operation in which exposure time EX2 set in frame period 72 is made longer than the upper limit per frame period (hereinafter referred to as the longest exposure time).
[0050] In Fig. 5, of the diagonal lines RR shown in Fig. 4, the diagonal line RR that forms the boundary between a frame period 72 and the next frame period 72 is changed to a thick solid line. This thick diagonal line RR indicates the timing of rolling readout driving in which pixel signals are read out only from the pixel line 62 and no pixel signals are read out from the pixel line 63. Also, in Fig. 5, compared to Fig. 4, the readout of pixel signals from the pixel line 63 in the third, sixth, and ninth frame periods 72 (i.e., the diagonal line RS2 immediately after the thick diagonal line RR) is omitted.
[0051] In the operation of the modified example shown in Fig. 5, at the end timing of frame period 72 immediately following frame period 71, pixel signals are not read out from pixel line 63. For this reason, steps S7 and S8 shown in Fig. 4 are deleted. Then, at the end timing of the second frame period after frame period 71, pixel signals are read out from pixel line 63. In this way, in the modified example of Fig. 5, exposure of pixel line 63 continues over two frame periods, thereby making exposure time EX2 longer than the longest exposure time.
[0052] According to the first modification, the exposure time EX2 can be made longer than the longest exposure time, so that it is possible to perform focusing control with high accuracy even for a dark subject. Furthermore, since pixel signals are read out from the pixel line 62 every frame period, even if the exposure time EX2 is longer, the update frequency of the live view image does not decrease. As a result, it is possible to improve the quality of the live view image during continuous shooting.
[0053] (Second modified example of the operation of the digital camera 100) 6 is a timing chart for explaining a second modified example of the operation of the digital camera 100. This second modified example shows an example of operation in which the exposure time EX2 set in the frame period 72 is made longer than in the example of FIG.
[0054] FIG. 6 is significantly different from FIG. 4 in that there are three frame periods 72 between a frame period 71 and the next frame period 71. Also, in FIG. 6, step S5 is changed to a process of driving the focus lens according to the drive amount predicted in step S4. Also, in FIG. 6, the diagonal line RR constituting the boundary between these three frame periods 72 is a thick line. This thick diagonal line RR indicates the timing of performing rolling read drive in which pixel signals are read only from the pixel line 62 and pixel signals are not read from the pixel line 63. Also, in FIG. 6, the rolling reset drive indicated by the diagonal line RS2 is performed only in the first frame period 72 of these three frame periods 72, and the rolling reset drive indicated by the diagonal line RS2 is not performed in the frame periods 72 other than the first frame period 72 of the three frame periods 72. In other words, the exposure of the pixel line 63 is continued over the three frame periods 72 following the frame period 71.
[0055] In the operation of the modified example shown in Fig. 6, at the end timings of the two frame periods 72 immediately following the frame period 71, pixel signals are not read out from the pixel line 63. For this reason, steps S7, S8, S10, and S11 shown in Fig. 4 are deleted. Then, at the end timing of the third frame period following the frame period 71, pixel signals are read out from the pixel lines 62 and 63. Then, updating of the live view image based on this pixel signal (step S21), focus detection based on this pixel signal (step S22), and prediction of the drive amount of the focus lens at the start of exposure of the third frame period 71 based on this focus detection result and past focus detection results (step S23) are performed.
[0056] After that, when the second frame period 71 ends, step S24 corresponding to step S2, step S25 corresponding to step S3, and step S26 corresponding to step S4 are performed. Then, the system control unit 11 drives the focus lens according to the drive amount predicted in step S26 (step S27). After that, the same processes as steps S6, S9, S21, S22, and S23 are repeated.
[0057] In this manner, in the modified example of FIG. 6, the exposure of pixel line 63 continues for three frame periods, thereby making the exposure time EX2 longer than the longest exposure time. According to this modified example, the exposure time EX2 can be made even longer than in the example of FIG. 5, so that it is possible to perform highly accurate focus control for darker subjects. Furthermore, because pixel signals from pixel line 62 are read out every frame period, the frequency with which the live view image is updated does not decrease even if the exposure time EX2 is longer. As a result, the quality of the live view image during continuous shooting can be improved.
[0058] (Preferred example of digital camera 100) Here, a preferred example of a method for predicting the drive amount of the focus lens will be described. For example, in step S11 of Fig. 4, the system control unit 11 predicts the drive amount of the focus lens based on the drive amount derived in step S3, the drive amount derived in step S7, and the drive amount derived in step S10. From these three drive amounts, the system control unit 11 obtains a linear function indicating the time change of the drive amount by the weighted least squares method, and derives the drive amount at the prediction timing as a predicted value from this linear function.
[0059] The system control unit 11 sets the weighting coefficients for the three drive amounts by this weighted least squares method to a relatively large value for the first drive amount (in the example of FIG. 4, the drive amount obtained in step S7 and step S10) derived based on pixel signals obtained by imaging with an exposure time suitable for focus detection, and sets the weighting coefficient for the second drive amount (in the example of FIG. 4, the drive amount obtained in step S3) derived based on pixel signals obtained by imaging with an exposure time suitable for recording to a value smaller than the weighting coefficient for the first drive amount. In this way, even if the exposure for imaging performed in the frame period 71 is not suitable for focus detection, the prediction accuracy of the drive amount can be improved.
[0060] The weighting coefficient of the second drive amount may be variable rather than fixed. For example, the system control unit 11 changes the weighting coefficient based on the imaging conditions (imaging sensitivity or exposure difference from exposure suitable for focus detection) of the imaging performed in the frame period 71. If the imaging conditions are in a state where the accuracy of focus detection can be ensured, the system control unit 11 sets the weighting coefficient of the second drive amount to a large value, and if the imaging conditions are in a state where the accuracy of focus detection cannot be ensured, the system control unit 11 sets the weighting coefficient of the second drive amount to a small value. For example, in a state where the imaging sensitivity is high, the accuracy of focus detection tends to decrease due to an increase in noise. Therefore, when the imaging sensitivity is less than a threshold value, the system control unit 11 sets the weighting coefficient of the first drive amount to the same as the weighting coefficient of the second drive amount, and when the imaging sensitivity is equal to or greater than the threshold value, the system control unit 11 sets the weighting coefficient of the first drive amount to a small value in inverse proportion to the magnitude of the imaging sensitivity. Furthermore, when the exposure difference is less than the threshold, the system control unit 11 sets the weighting coefficient of the first drive amount to the same value as the weighting coefficient of the second drive amount, and when the exposure difference is equal to or greater than the threshold, the system control unit 11 reduces the weighting coefficient of the first drive amount in inverse proportion to the magnitude of the exposure difference. In this way, it is possible to improve the accuracy of prediction of the drive amount.
[0061] (Another preferred example of the digital camera 100) In the first and second modified examples, while the exposure time EX2 can be made longer than the longest exposure time, the frequency of focus detection decreases and the frame rate of continuous shooting decreases compared to when the exposure time EX2 is equal to or shorter than the longest exposure time. Therefore, it is preferable to increase the prediction accuracy of the drive amount of the focus lens while keeping the exposure time EX2 equal to or shorter than the longest exposure time.
[0062] For example, if the system control unit 11 sets the exposure time EX2 to the longest exposure time but is unable to obtain proper exposure (exposure suitable for focus detection) of the pixel line 63 determined according to the brightness of the target subject, the system control unit 11 increases the imaging sensitivity of the imaging element 5 for imaging during the frame period 72.
[0063] FIG. 7 shows an example of a program diagram that defines the relationship between the exposure value (EV (Exposure Value) value) and the TV (time value) value corresponding to the exposure time when the imaging sensitivity and the F-number are predetermined values. FIG. 7 shows a program diagram when the above-mentioned longest exposure time is TV5.6. As shown in FIG. 7, when the proper exposure of the pixel line 63 is in the range from EV23 to about EV8, the proper exposure is realized by adjusting the TV value (exposure time). When the proper exposure of the pixel line 63 becomes EV7.5 or less, the proper exposure is realized by changing the imaging sensitivity between the above-mentioned predetermined value and the preset upper limit value while maintaining TV5.6. The thick dashed line in the figure shows the change in the program diagram due to the increase in imaging sensitivity. Then, when the proper exposure of the pixel line 63 further decreases and falls below EV5.5, even if the imaging sensitivity is set to the preset upper limit value, the proper exposure cannot be realized unless the TV value is lowered. Therefore, the TV value is changed to a value smaller than TV5.6, and the proper exposure is ensured (thick solid line on the left side in FIG. 7). Changing the TV value to a value smaller than TV5.6 means switching from the operation shown in FIG. 4 (an operation in which the exposure of pixel line 63 is completed within one frame period 72) to the operation shown in FIG. 5 or FIG. 6 (an operation in which the exposure of pixel line 63 is continued over multiple frame periods 72).
[0064] In this way, if proper exposure for focus detection cannot be achieved even when the exposure time EX2 is set to the longest exposure time, the imaging sensitivity can be increased to a degree that allows proper exposure to be achieved without extending the longest exposure time, thereby reducing the number of times that the exposure time EX2 exceeds the longest exposure time. This ensures the accuracy of focus control while minimizing the decrease in the frequency of focus detection and the decrease in the frame rate of continuous shooting.
[0065] In the above description, if proper exposure cannot be achieved even if the imaging sensitivity is increased to the predetermined upper limit, the exposure time EX2 is changed to a value greater than the longest exposure time. However, even if proper exposure cannot be achieved by increasing the imaging sensitivity to the predetermined upper limit, the accuracy of focus detection may be ensured depending on the situation. For example, even if imaging is performed using pixel line 63 in a state in which proper exposure cannot be achieved, if the maximum value max of the curve shown in FIG. 3 obtained by this imaging is large, the minimum value min can be determined with high accuracy, and the accuracy of focus detection can be ensured.
[0066] Therefore, when proper exposure of the pixel line 63 cannot be obtained even if the exposure time EX2 is set to the longest exposure time and the imaging sensitivity is set to the default upper limit, the system control unit 11 sets the exposure time EX2 to the longest exposure time and the imaging sensitivity to the default upper limit to perform imaging control for display, as long as information based on pixel signals output from the pixel line 63 in the immediately preceding imaging (imaging in frame period 71) satisfies a default condition. The default condition is, for example, that the ratio (max / min) of the maximum value max and the minimum value min of a curve showing the result of correlation calculation based on pixel signals output from the pixel line 63 exceeds a threshold, or that the difference (max-min) between the maximum value max and the minimum value min exceeds a threshold, etc.
[0067] FIG. 8 shows an example of a program diagram that defines the relationship between the exposure value and the TV value when the imaging sensitivity and the F-number are predetermined values. FIG. 8 shows a program diagram when the above-mentioned longest exposure time is TV5.6. As shown in FIG. 8, when the proper exposure is in the range from EV23 to about EV8, the proper exposure is realized by adjusting the TV value. When the proper exposure is EV7.5 or less, the proper exposure is realized by changing the imaging sensitivity between the above-mentioned predetermined value and the preset upper limit value while maintaining TV5.6 (thick dashed line in the figure). Then, when the proper exposure further decreases to below EV5.5, if the preset condition is satisfied, the imaging sensitivity is set to the preset upper limit value, and the exposure time EX2 is set to the longest exposure time, that is, in a state of underexposure where the exposure is lower than the proper exposure, imaging control for display is performed (thin dashed line in the figure). On the other hand, when the proper exposure is below EV5.5 and the preset condition is not satisfied, focus detection accuracy cannot be ensured and proper exposure cannot be realized unless the TV value is lowered. For this reason, the TV value is changed to a value smaller than TV5.6, and the proper exposure is ensured (thick solid line on the left side in FIG. 8).
[0068] In this way, if it is difficult to ensure proper exposure even if the exposure time EX2 is set to the longest exposure time and the imaging sensitivity is increased to the default upper limit, the chances that the exposure time EX2 will exceed the longest exposure time can be reduced by performing imaging control for display with underexposure as long as the default conditions are met. This ensures the accuracy of focus control while minimizing the decrease in the frequency of focus detection and the decrease in the frame rate of continuous shooting.
[0069] Next, a configuration of a smartphone, which is another embodiment of the imaging device of the present invention, will be described.
[0070] Fig. 9 shows the external appearance of smartphone 200. Smartphone 200 shown in Fig. 9 has a flat housing 201, and is provided on one surface of housing 201 with display panel 202 as a display unit and display input unit 204 which is integrated with operation panel 203 as an input unit.
[0071] Moreover, such a housing 201 includes a speaker 205, a microphone 206, an operation unit 207, and a camera unit 208. Note that the configuration of the housing 201 is not limited to this, and for example, a configuration in which the display unit and the input unit are independent, or a configuration having a folding structure or a sliding mechanism may be adopted.
[0072] FIG. 10 is a block diagram showing a configuration of the smartphone 200 shown in FIG.
[0073] As shown in FIG. 10, the main components of the smartphone include a wireless communication unit 210, a display input unit 204, a call unit 211, an operation unit 207, a camera unit 208, a memory unit 212, an external input / output unit 213, a GNSS (Global Navigation Satellite System) receiving unit 214, a motion sensor unit 215, a power supply unit 216, and a main control unit 220.
[0074] The smartphone 200 also has, as its main function, a wireless communication function for performing mobile wireless communication via a base station device BS (not shown) and a mobile communication network NW (not shown).
[0075] The wireless communication unit 210 performs wireless communication with the base station device BS accommodated in the mobile communication network NW in accordance with instructions from the main control unit 220. Using this wireless communication, various file data such as voice data and image data, e-mail data, etc. are sent and received, and web data, streaming data, etc. are received.
[0076] The display input unit 204 is a so-called touch panel that displays images (still images and moving images) or text information, etc. under the control of the main control unit 220 to visually convey information to the user and detects user operations on the displayed information, and is equipped with a display panel 202 and an operation panel 203.
[0077] The display panel 202 uses a liquid crystal display (LCD), an organic electro-luminescence display (OLED), or the like as a display device.
[0078] The operation panel 203 is a device placed so that an image displayed on the display surface of the display panel 202 can be seen, and detects one or more coordinates operated by a user's finger or a stylus. When this device is operated by the user's finger or a stylus, a detection signal generated by the operation is output to the main control unit 220. Next, the main control unit 220 detects the operation position (coordinates) on the display panel 202 based on the received detection signal.
[0079] As shown in FIG. 10, a display panel 202 and an operation panel 203 of a smartphone 200, which is illustrated as one embodiment of the imaging device of the present invention, are integrated together to form a display input unit 204, and the operation panel 203 is positioned so as to completely cover the display panel 202.
[0080] When such an arrangement is adopted, operation panel 203 may also have a function of detecting user operations in an area outside display panel 202. In other words, operation panel 203 may have a detection area for an overlapping portion that overlaps display panel 202 (hereinafter referred to as a display area), and a detection area for the other outer edge portion that does not overlap display panel 202 (hereinafter referred to as a non-display area).
[0081] The size of the display area and the size of the display panel 202 may be completely the same, but they do not necessarily have to be the same. Also, the operation panel 203 may have two sensitive areas, an outer edge part and the other inner part. Furthermore, the width of the outer edge part is designed appropriately according to the size of the housing 201, etc.
[0082] Furthermore, the position detection method used in the operation panel 203 may be a matrix switch method, a resistive film method, a surface acoustic wave method, an infrared method, an electromagnetic induction method, a capacitance method, or the like, and any method may be used.
[0083] The call unit 211 is equipped with a speaker 205 or a microphone 206, and converts the user's voice input through the microphone 206 into voice data that can be processed by the main control unit 220 and outputs it to the main control unit 220, or decodes voice data received by the wireless communication unit 210 or the external input / output unit 213 and outputs it from the speaker 205.
[0084] Also, as shown in FIG. 9, for example, speaker 205 can be mounted on the same surface as display input unit 204, and microphone 206 can be mounted on the side surface of housing 201.
[0085] The operation unit 207 is a hardware key using a key switch or the like, and receives instructions from a user. For example, as shown in Fig. 9, the operation unit 207 is a push-button switch mounted on the side of the housing 201 of the smartphone 200, which is turned on when pressed with a finger or the like, and turned off by the restoring force of a spring or the like when the finger is released.
[0086] The storage unit 212 stores the control program and control data of the main control unit 220, application software, address data associated with names or telephone numbers of communication partners, data of sent and received e-mails, Web data downloaded by Web browsing, downloaded content data, and also temporarily stores streaming data, etc. The storage unit 212 is composed of an internal storage unit 217 built into the smartphone and an external storage unit 218 having a removable external memory slot.
[0087] Each of the internal memory unit 217 and the external memory unit 218 constituting the memory unit 212 is realized using a storage medium such as a flash memory type, a hard disk type, a multimedia card micro type, a card-type memory (e.g., MicroSD (registered trademark) memory, etc.), a RAM (Random Access Memory), a ROM (Read Only Memory), etc.
[0088] The external input / output unit 213 serves as an interface with all external devices connected to the smartphone 200, and is for directly or indirectly connecting to other external devices via communication (e.g., Universal Serial Bus (USB), IEEE1394, Bluetooth (registered trademark), RFID (Radio Frequency Identification), Infrared Data Association (IrDA) (registered trademark), UWB (Ultra Wideband) (registered trademark), ZigBee (registered trademark), etc.) or a network (e.g., Ethernet (registered trademark), wireless LAN (Local Area Network), etc.).
[0089] Examples of external devices that may be connected to the smartphone 200 include wired / wireless headsets, wired / wireless external chargers, wired / wireless data ports, memory cards connected via card sockets, SIM (Subscriber Identity Module Card) / UIM (User Identity Module Card) cards, external audio / video devices connected via audio / video I / O (Input / Output) terminals, wirelessly connected external audio / video devices, wired / wirelessly connected smartphones, wired / wirelessly connected personal computers, wired / wirelessly connected personal computers, earphones, etc.
[0090] The external input / output unit 213 can transmit data received from such an external device to each component inside the smartphone 200, or transmit data inside the smartphone 200 to an external device.
[0091] The GNSS receiver 214 receives GNSS signals transmitted from the GNSS satellites ST1 to STn according to instructions from the main controller 220, executes positioning calculation processing based on the multiple received GNSS signals, and detects a position consisting of the latitude, longitude, and altitude of the smartphone 200. When the GNSS receiver 214 can obtain position information from the wireless communication unit 210 or the external input / output unit 213 (for example, wireless LAN), it can also detect the position using the position information.
[0092] The motion sensor unit 215 includes, for example, a three-axis acceleration sensor and detects the physical movement of the smartphone 200 according to an instruction from the main control unit 220. By detecting the physical movement of the smartphone 200, the moving direction or acceleration of the smartphone 200 is detected. The detection result is output to the main control unit 220.
[0093] The power supply unit 216 supplies power stored in a battery (not shown) to each unit of the smartphone 200 in accordance with instructions from the main control unit 220.
[0094] The main control unit 220 includes a microprocessor, operates according to the control program and control data stored in the storage unit 212, and controls each unit of the smartphone 200. The microprocessor of the main control unit 220 has the same functions as the system control unit 11. The main control unit 220 also includes a mobile communication control function that controls each unit of the communication system to perform voice communication or data communication via the wireless communication unit 210, and an application processing function.
[0095] The application processing function is realized by the main control unit 220 operating in accordance with the application software stored in the storage unit 212. Examples of the application processing function include an infrared communication function for controlling the external input / output unit 213 to perform data communication with a counterpart device, an email function for sending and receiving emails, and a web browsing function for browsing web pages.
[0096] The main control unit 220 also has an image processing function for displaying video on the display input unit 204 based on image data (still image or moving image data) such as received data or downloaded streaming data.
[0097] The image processing function refers to a function in which the main control unit 220 decodes the image data, performs image processing on the decoded result, and displays the image on the display input unit 204.
[0098] Furthermore, the main control unit 220 executes display control for the display panel 202 and operation detection control for detecting user operations via the operation unit 207 and the operation panel 203 .
[0099] By executing display control, main control unit 220 displays icons for starting application software or software keys such as scroll bars, or displays a window for creating an e-mail.
[0100] The scroll bar refers to a software key for receiving an instruction to move the displayed portion of an image, such as a large image that cannot fit within the display area of the display panel 202.
[0101] In addition, by executing operation detection control, the main control unit 220 detects user operations through the operation unit 207, accepts operations on the above-mentioned icons and input of character strings into the input field of the above-mentioned window through the operation panel 203, or accepts a request to scroll the displayed image through a scroll bar.
[0102] Furthermore, by executing operation detection control, the main control unit 220 determines whether the operation position on the operation panel 203 is an overlapping portion (display area) that overlaps with the display panel 202, or an outer edge portion (non-display area) that does not overlap with the display panel 202, and is equipped with a touch panel control function that controls the sensitive area of the operation panel 203 or the display position of the software key.
[0103] Furthermore, the main control unit 220 can also detect a gesture operation on the operation panel 203 and execute a preset function in response to the detected gesture operation.
[0104] The gesture operation is not a simple touch operation as in the past, but rather refers to an operation in which a path is drawn with a finger or the like, multiple positions are designated simultaneously, or a combination of these to draw a path for at least one of multiple positions.
[0105] The camera section 208 includes the imaging section 50 in the digital camera shown in FIG.
[0106] The captured image data generated by the camera unit 208 can be stored in the storage unit 212 or output via the external input / output unit 213 or the wireless communication unit 210.
[0107] In the smartphone 200 shown in FIG. 9, the camera unit 208 is mounted on the same surface as the display input unit 204, but the mounting position of the camera unit 208 is not limited to this, and the camera unit 208 may be mounted on the back surface of the display input unit 204.
[0108] In addition, the camera unit 208 can be used for various functions of the smartphone 200. For example, an image acquired by the camera unit 208 can be displayed on the display panel 202, or an image from the camera unit 208 can be used as one of the operation inputs for the operation panel 203.
[0109] Furthermore, when the GNSS receiver 214 detects a position, it can also detect the position by referring to an image from the camera unit 208. Furthermore, it can also determine the optical axis direction of the camera unit 208 of the smartphone 200 or the current usage environment by referring to an image from the camera unit 208 without using a three-axis acceleration sensor or by using the same in combination with a three-axis acceleration sensor. Of course, the image from the camera unit 208 can also be used in application software.
[0110] In addition, image data of still or video images can be supplemented with position information acquired by the GNSS receiving unit 214, voice information acquired by the microphone 206 (which may be converted to text information by the main control unit, etc.), posture information acquired by the motion sensor unit 215, etc., and stored in the memory unit 212 or output via the external input / output unit 213 or wireless communication unit 210.
[0111] The smartphone 200 configured as above can also perform focus control at high frequency.
[0112] As described above, this specification describes at least the following items. Note that, in parentheses, corresponding components and the like in the above-mentioned embodiment are shown, but the present invention is not limited to these.
[0113] (1) an image sensor (image sensor 5) including a first light receiving region (pixel line 63) in which a pixel group including focus detection pixels (focus detection pixels 61b and focus detection pixels 61c) is arranged, and a second light receiving region (pixel line 62) in which a pixel group not including the focus detection pixels is arranged; A processor (system control unit 11), The processor is a first control (image capture control for recording) for causing the image sensor to capture an image during a first exposure time (exposure time EX1); and performing a second control (image capture control for display) in which an exposure time of the second light receiving region is set as the first exposure time and an exposure time of the first light receiving region is set as a second exposure time (exposure time EX2) to cause the image capture element to capture an image. Imaging device.
[0114] (2) The imaging device according to (1), The second exposure time is different from the first exposure time; Imaging device.
[0115] (3) The imaging device according to (2), The second exposure time is longer than the first exposure time. Imaging device.
[0116] (4) An imaging device according to any one of (1) to (3), The first light receiving area and the second light receiving area are each composed of a plurality of pixel lines. Imaging device.
[0117] (5) An imaging device according to any one of (1) to (4), The processor is The first control is performed a plurality of times, The second control is performed at least once between the first control and the next first control. Imaging device.
[0118] (6) The imaging device according to (5), The processor is The second control is performed multiple times in succession between the first control and the next first control, The exposure of the first light receiving region is continued during the plurality of second controls. Imaging device.
[0119] (7) The imaging device according to (6), The processor is outputting signals from the pixel group in the second light receiving region after the start of the second control multiple times is performed for each of the second control multiple times; Imaging device.
[0120] (8) An imaging device according to any one of (1) to (7), The processor is using image data based on a signal output from the imaging element by the first control for recording and display; image data based on a signal output from the pixel group of the second light receiving region by the second control is used only for display among recording and display; Imaging device.
[0121] (9) The imaging device according to (8), The processor is using a first signal output from a pixel group in the first light receiving region by the first control to drive a focus lens disposed between the image sensor and a subject; a second signal output from the pixel group in the first light receiving region by the second control is used to drive the focus lens; Imaging device.
[0122] (10) The imaging device according to (9), The processor is predicting a drive amount of the focus lens in the first control thereafter based on a first drive amount of the focus lens determined based on the first signal output from the pixel group of the first light receiving region by the first control and a second drive amount of the focus lens determined based on the second signal output from the pixel group of the first light receiving region by the second control subsequent to the first control; a weighting coefficient of the first drive amount used in predicting the drive amount is set to be smaller than a weighting coefficient of the second drive amount; Imaging device.
[0123] (11) The imaging device according to (10), The processor controls the weighting coefficient of the first driving amount based on an imaging condition in the first control. Imaging device.
[0124] (12) An imaging device according to any one of (1) to (11), The processor is The second exposure time is set in accordance with the brightness of a subject imaged by the image sensor; The first control is performed a plurality of times, performing at least one second control between the first control and the next first control; When proper exposure of the first light receiving area determined according to the brightness of the subject cannot be obtained in one second control even if the second exposure time is set to an upper limit value (longest exposure time) per one second control, the imaging sensitivity of the imaging element in the second control is increased. Imaging device.
[0125] (13) The imaging device according to (12), The processor is When the proper exposure is not obtained even if the second exposure time is set to the upper limit value and the imaging sensitivity is set to a predetermined upper limit value, the second control is continuously performed a plurality of times between the first control and the next first control, and exposure of the first light receiving region is continued between the plurality of second controls. Imaging device.
[0126] (14) The imaging device according to (12), The processor is when the proper exposure is not obtained even if the second exposure time is set to the upper limit value and the imaging sensitivity is set to a predetermined upper limit value, the second exposure time is set to the upper limit value and the imaging sensitivity is set to the predetermined upper limit value, as long as information based on signals output from the focus detection pixels satisfies a predetermined condition, and the second control is performed. Imaging device.
[0127] (15) The imaging device according to (14), The processor is When the proper exposure is not obtained even if the second exposure time is set to the upper limit value and the imaging sensitivity is set to the predetermined upper limit value, and the predetermined condition is not satisfied, the second control is performed multiple times in succession between the first control and the next first control, and exposure of the first light receiving region is continued between the multiple second controls. Imaging device.
[0128] (16) 1. An imaging control method for controlling an imaging element including a first light receiving region in which a pixel group including focus detection pixels is arranged, and a second light receiving region in which a pixel group not including the focus detection pixels is arranged, a first control for causing the image sensor to capture an image during a first exposure time; and performing a second control in which an exposure time of the second light receiving region is set as the first exposure time and an exposure time of the first light receiving region is set as a second exposure time to cause the image sensor to capture an image. Imaging control method.
[0129] (17) An imaging control program for controlling an imaging element including a first light receiving region in which a pixel group including focus detection pixels is arranged, and a second light receiving region in which a pixel group not including the focus detection pixels is arranged, The processor: a first control for causing the image sensor to capture an image during a first exposure time; and performing a second control in which an exposure time of the second light receiving region is set as the first exposure time and an exposure time of the first light receiving region is set as a second exposure time to cause the image sensor to capture an image. Imaging control program. [Explanation of symbols]
[0130] 1 Imaging lens 2 Aperture 4 Lens control section 5. Image sensor 8 Lens drive unit 9 Aperture drive unit 10. Image sensor driver 11 System control section 14,207 Operation section 15 Memory control section 16 Memory 17 Digital signal processing section 20 External memory control unit 21 Recording media 22a Display Controller 22b Display surface 22 Display device 24 Control Bus 25 Data Bus 40 Lens device 50 Imaging unit 60 imaging surface 61a Normal pixel 61b, 61c Focus detection pixels 61 pixels 62,63 pixel line 64 Drive circuit 65 Signal Processing Circuit 71,72 frame period 100A Main Unit 100 Digital Camera 200 Smartphones 201 Case 202 Display Panel 203 Operation Panel 204 Display and input section 205 Speaker 206 Microphone 208 Camera Club 210 Wireless Communication Department 211 Telephone section 212 Storage section 213 External input / output section 214 GNSS receiver 215 Motion Sensor Part 216 Power supply section 217 Internal storage 218 External memory unit 220 Main control unit
Claims
1. an image sensor including a first light receiving region in which a pixel group including focus detection pixels is arranged, and a second light receiving region in which a pixel group not including the focus detection pixels is arranged; a processor; The processor, a first control for causing the image sensor to capture an image during a first exposure time; and performing a second control in which an exposure time of the second light receiving area is set to the first exposure time and an exposure time of the first light receiving area is set to a second exposure time to cause the image sensor to capture an image. Imaging device.
2. 2. The imaging device according to claim 1, The second exposure time is different from the first exposure time. Imaging device.
3. 3. The imaging device according to claim 2, The second exposure time is longer than the first exposure time. Imaging device.
4. 4. The imaging device according to claim 1, The first light receiving region and the second light receiving region are each composed of a plurality of pixel lines. Imaging device.
5. 5. The imaging device according to claim 1, The processor, The first control is performed a plurality of times; The second control is performed at least once between the first control and the next first control. Imaging device.
6. 6. The imaging device according to claim 5, The processor, The second control is performed multiple times in succession between the first control and the next first control, The exposure of the first light receiving region is continued between the multiple second controls. Imaging device.
7. 7. The imaging device according to claim 6, The processor, outputting signals from the pixel group in the second light receiving region after the start of the second control multiple times is performed for each of the second control multiple times; Imaging device.
8. 8. The imaging device according to claim 1, The processor, using image data based on a signal output from the imaging element by the first control for recording and display; and using image data based on a signal output from the pixel group of the second light receiving region by the second control only for display among recording and display. Imaging device.
9. 9. The imaging device according to claim 8, The processor, a first signal output from a pixel group in the first light receiving region by the first control is used to drive a focus lens disposed between the image sensor and a subject; a second signal output from the pixel group of the first light receiving region by the second control is used to drive the focus lens; Imaging device.
10. 10. The imaging device according to claim 9, The processor, predicting a drive amount of the focus lens in the first control thereafter based on a first drive amount of the focus lens determined based on the first signal output from the pixel group of the first light receiving region by the first control and a second drive amount of the focus lens determined based on the second signal output from the pixel group of the first light receiving region by the second control after the first control; a weighting coefficient of the first drive amount used for predicting the drive amount is set to be smaller than a weighting coefficient of the second drive amount; Imaging device.
11. The imaging device according to claim 10, The processor controls the weighting coefficient of the first driving amount based on an imaging condition in the first control. Imaging device.
12. 12. The imaging device according to claim 1, The processor, The second exposure time is set in accordance with the brightness of a subject imaged by the image sensor; The first control is performed a plurality of times; performing at least one second control between the first control and the next first control; When proper exposure of the first light receiving area determined according to the brightness of the subject cannot be obtained in one second control even if the second exposure time is set to an upper limit value per one second control, the imaging sensitivity of the imaging element in the second control is increased. Imaging device.
13. 13. The imaging device according to claim 12, The processor, When the proper exposure is not obtained even if the second exposure time is set to the upper limit value and the imaging sensitivity is set to a predetermined upper limit value, the second control is continuously performed a plurality of times between the first control and the next first control, and exposure of the first light receiving region is continued between the plurality of second controls. Imaging device.
14. 13. The imaging device according to claim 12, The processor, when the proper exposure cannot be obtained even if the second exposure time is set to the upper limit value and the imaging sensitivity is set to a predetermined upper limit value, the second control is performed by setting the second exposure time to the upper limit value and setting the imaging sensitivity to the predetermined upper limit value as long as information based on signals output from the focus detection pixels satisfies a predetermined condition. Imaging device.
15. 15. The imaging device according to claim 14, The processor, when the proper exposure is not obtained even if the second exposure time is set to the upper limit value and the imaging sensitivity is set to the predetermined upper limit value, and the predetermined condition is not satisfied, the second control is performed multiple times in succession between the first control and the next first control, and exposure of the first light receiving region is continued between the multiple second controls. Imaging device.
16. 1. An imaging control method for controlling an imaging element including a first light receiving region in which a pixel group including focus detection pixels is arranged, and a second light receiving region in which a pixel group not including the focus detection pixels is arranged, comprising: a first control for causing the image sensor to capture an image during a first exposure time; and performing a second control in which an exposure time of the second light receiving area is set to the first exposure time and an exposure time of the first light receiving area is set to a second exposure time to cause the image sensor to capture an image. Imaging control method.
17. An imaging control program for controlling an imaging element including a first light receiving region in which a pixel group including focus detection pixels is arranged, and a second light receiving region in which a pixel group not including the focus detection pixels is arranged, The processor: a first control for causing the image sensor to capture an image during a first exposure time; and performing a second control in which an exposure time of the second light receiving area is set to the first exposure time and an exposure time of the first light receiving area is set to a second exposure time to cause the image sensor to capture an image. Imaging control program.
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