JP6354246B2 - IMAGING DEVICE, IMAGING DEVICE CONTROL METHOD, AND CONTROL PROGRAM - Google Patents

Description

  The present invention relates to an imaging apparatus, an imaging apparatus control method, and a control program.

  There has been proposed an electronic apparatus provided with an imaging element in which a back-illuminated imaging chip and a signal processing chip are laminated (hereinafter, this imaging element is referred to as a laminated imaging element) (for example, see Patent Document 1). The multilayer imaging element is laminated so that the back-illuminated imaging chip and the signal processing chip are connected via a micro bump for each block unit including a plurality of pixels.

JP 2006-49361 A

  However, there are few proposals for acquiring an image by capturing an image for each of a plurality of block units in a conventional imaging device including a multilayer imaging element, and the usability of an imaging device including a multilayer imaging element is not sufficient.

  An object of an aspect of the present invention is to perform imaging with appropriate brightness for a plurality of subjects.

According to an aspect of the present invention, there is provided an imaging device for imaging a first subject and a second subject irradiated with illumination light within an imaging field, wherein the first photoelectric conversion converts light from the first subject into electric charge. A first imaging region having a plurality of first pixels, and a second photoelectric conversion unit that converts light from the second subject into charges, and a second photoelectric conversion unit. A second imaging region having a plurality of second pixels having a second transfer unit that transfers a charge of the photoelectric conversion unit, and a signal that is connected to the plurality of first pixels and that controls a transfer operation of the first transfer unit is supplied. A first wiring connected to the plurality of second pixels and supplied with a signal for controlling the transfer operation of the second transfer unit, and a second wiring different from the first wiring, and photoelectric conversion of the plurality of first pixels. A first output line for outputting a signal generated by the converted charge, and a plurality of the second pixels; A first output for acquiring an image sensor having a second output line for outputting a signal generated by the electric charge converted by the photoelectric conversion, and position information of the first subject and the second subject in the imaging visual field. And the first subject and the second subject irradiated with the illumination light, based on the position information so that the first subject and the second subject can obtain a predetermined amount of exposure by the illumination light irradiation, respectively. An imaging device is provided that includes a control unit that independently controls the imaging conditions of the first imaging region and the imaging conditions of the second imaging region.
According to an aspect of the present invention, there is provided a control method for an imaging apparatus having an imaging device that images light from a first subject and a second subject irradiated with illumination light within an imaging field, the imaging device comprising: A first imaging region having a plurality of first pixels having a first photoelectric conversion unit that converts light from one subject into electric charge and a first transfer unit that transfers electric charge of the first photoelectric conversion unit; A second imaging region having a plurality of second pixels each having a second photoelectric conversion unit that converts light into charges and a second transfer unit that transfers charges of the second photoelectric conversion unit; and a plurality of first pixels, Different from the first wiring to which a signal for controlling the transfer operation of the first transfer unit is supplied and the first wiring that is connected to the plurality of second pixels and to which a signal for controlling the transfer operation of the second transfer unit is supplied. Generated by charges converted by photoelectric conversion of the second wiring and the plurality of first pixels A first output line for outputting a signal, and a second output line for outputting a signal generated by electric charges converted by photoelectric conversion of a plurality of second pixels. The step of acquiring position information relating to the presence position in the imaging field of view, and when imaging the first subject and the second subject irradiated with the illumination light, the first subject and the second subject are each given a predetermined amount due to the illumination light irradiation. An imaging apparatus control method comprising: independently controlling the imaging condition of the first imaging area and the imaging condition of the second imaging area based on the position information so as to obtain an exposure of .
According to an aspect of the present invention, there is provided a control program used in an imaging apparatus having an imaging device that images light from a first subject and a second subject irradiated with illumination light within an imaging field. Includes a first imaging region having a plurality of first pixels each having a first photoelectric conversion unit that converts light from the first subject into charges and a first transfer unit that transfers charges of the first photoelectric conversion unit; A second imaging region having a plurality of second pixels having a second photoelectric conversion unit that converts light from the subject into charges and a second transfer unit that transfers charges of the second photoelectric conversion unit; and a plurality of first pixels A first wiring connected and supplied with a signal for controlling a transfer operation of the first transfer unit; and a first wiring connected to a plurality of second pixels and supplied with a signal for controlling the transfer operation of the second transfer unit. A second wiring different from the wiring, and a power converted by photoelectric conversion of the plurality of first pixels. And a second output line for outputting a signal generated by charges converted by photoelectric conversion of a plurality of second pixels, and a first subject and a first output line. Processing for acquiring position information regarding the presence positions of two subjects in the imaging field, and imaging of the first subject and the second subject irradiated with illumination light, the first subject and the second subject are irradiated by illumination light. Control for causing the imaging apparatus to execute processing for independently controlling the imaging conditions of the first imaging area and the imaging conditions of the second imaging area based on the position information so that each of the images can obtain a predetermined amount of exposure. A program is provided.
According to the first aspect of the present invention, there is provided an imaging device that images a first subject and a second subject irradiated with illumination light within an imaging field, and having an imaging element that images light from the subject. A first acquisition unit that acquires position information regarding the positions of the first subject and the second subject in the imaging field, and both subjects subject to illumination light irradiation when imaging both subjects irradiated with illumination light. A control unit that independently controls the imaging condition of the pixel corresponding to the first subject and the imaging condition of the pixel corresponding to the second subject based on the position information so that a predetermined amount of exposure can be obtained. An imaging device is provided.

  According to the second aspect of the present invention, there is provided a control method for an imaging apparatus having an imaging device for imaging light from a first subject illuminated with illumination light and a light from a second subject within an imaging field. And obtaining the position information regarding the position of the second subject in the imaging field and capturing both subjects irradiated with illumination light, each subject obtains a predetermined amount of exposure by illumination light illumination. An imaging device control method comprising: independently controlling an imaging condition of a pixel corresponding to a first subject and an imaging condition of a pixel corresponding to a second subject based on position information Is done.

  According to the third aspect of the present invention, there is provided a control program used in an imaging apparatus having an imaging device that images light from a first subject and a second subject irradiated with illumination light within an imaging field. A process of acquiring position information relating to the positions of the first and second subjects in the imaging field of view, and when imaging both subjects irradiated with illumination light, both subjects are each given a predetermined amount due to illumination light irradiation. In order to obtain exposure, the imaging apparatus executes processing for independently controlling the imaging condition of the pixel corresponding to the first subject and the imaging condition of the pixel corresponding to the second subject based on the position information. A control program is provided.

  According to the present invention, it is possible to perform imaging with appropriate brightness for a plurality of subjects.

It is sectional drawing of the image pick-up element of 1st Embodiment. It is a figure explaining the pixel arrangement | sequence and unit group of an imaging chip. It is a circuit diagram corresponding to the unit group of an imaging chip. It is a block diagram which shows the functional structure of an image pick-up element. It is a figure which shows the block and pixel for a phase difference detection which are set to the pixel area | region of an imaging chip. It is a cross-sectional view which shows schematic structure of the digital camera which is an example of an electronic device. It is a block diagram which shows the structure of the digital camera which concerns on 1st Embodiment. It is a figure which shows the positional relationship of a digital camera and a 1st to-be-photographed object and a 2nd to-be-photographed object. It is a graph which shows the relationship between distance and the light quantity from a light emission part. It is a graph which shows the relationship between time and the light quantity from a light emission part. It is a figure which shows the example of the image which image | photographed the 1st to-be-photographed object and the 2nd to-be-photographed object with the digital camera which concerns on 1st Embodiment. It is a flowchart for demonstrating the imaging | photography operation | movement which the system control part of 1st Embodiment performs. It is a figure which shows the example of the image for demonstrating the white balance adjustment by the image process part of 1st Embodiment. It is a block diagram which shows the specific structure of the signal processing chip concerning 2nd Embodiment. It is a flowchart for demonstrating the setting process which the arithmetic circuit of 2nd Embodiment performs. It is a flowchart for demonstrating the imaging | photography operation | movement which the system control part of 3rd Embodiment performs. It is a graph which shows the relationship between the timing of pre light emission and this light emission, and light quantity. FIG. It is a block diagram which shows the structure of the imaging device and electronic device which concern on 4th Embodiment.

  FIG. 1 is a cross-sectional view of an image sensor 100 according to the first embodiment. The image sensor 100 is described in Japanese Patent Application No. 2012-139026 filed earlier by the present applicant. The imaging device 100 includes an imaging chip 113 that outputs a pixel signal corresponding to incident light, a signal processing chip 111 that processes the pixel signal output from the imaging chip 113, and a memory that stores the pixel signal processed by the signal processing chip 111. Chip 112. The imaging chip 113, the signal processing chip 111, and the memory chip 112 are stacked, and the imaging chip 113 and the signal processing chip 111 are electrically connected to each other by a conductive bump 109 such as Cu. Further, the signal processing chip 111 and the memory chip 112 are electrically connected to each other by a conductive bump 109 such as Cu.

  As indicated by the illustrated coordinate axes, incident light is incident mainly in the positive direction of the Z axis. In the present embodiment, in the imaging chip 113, the surface on the side where incident light is incident is referred to as a back surface. Further, as indicated by the coordinate axes, the left direction on the paper orthogonal to the Z axis is the X axis plus direction, and the front side of the paper orthogonal to the Z axis and the X axis is the Y axis plus direction. In the following several figures, the coordinate axes are displayed so that the orientation of each figure can be understood with reference to the coordinate axes of FIG.

  An example of the imaging chip 113 is a back-illuminated MOS image sensor. The PD layer 106 is disposed on the back side of the wiring layer 108. The PD layer 106 includes a plurality of photodiodes (Photodiode; hereinafter referred to as PD) 104 that are two-dimensionally arranged and accumulate electric charges according to incident light, and a transistor 105 provided corresponding to the PD 104. .

  A color filter 102 is provided on the incident side of incident light in the PD layer 106 via a passivation film 103. The color filter 102 is a filter that passes a specific wavelength region of visible light. The color filter 102 has a plurality of types that transmit different wavelength regions, and has a specific arrangement corresponding to each of the PDs 104. The arrangement of the color filter 102 will be described later. A set of the color filter 102, the PD 104, and the transistor 105 forms one pixel.

  On the incident light incident side of the color filter 102, a microlens 101 is provided corresponding to each pixel. The microlens 101 condenses incident light toward the corresponding PD 104.

  The wiring layer 108 includes a wiring 107 that transmits the pixel signal from the PD layer 106 to the signal processing chip 111. The wiring 107 may be multilayer, and a passive element and an active element may be provided. A plurality of bumps 109 are disposed on the surface of the wiring layer 108. The plurality of bumps 109 are aligned with the plurality of bumps 109 provided on the opposing surface of the signal processing chip 111. Then, by pressing the imaging chip 113 and the signal processing chip 111, the aligned bumps 109 are joined and electrically connected.

  Similarly, a plurality of bumps 109 are disposed on the mutually facing surfaces of the signal processing chip 111 and the memory chip 112. These bumps 109 are aligned with each other. Then, when the signal processing chip 111 and the memory chip 112 are pressurized or the like, the aligned bumps 109 are joined and electrically connected.

  The bonding between the bumps 109 is not limited to Cu bump bonding by solid phase diffusion, and micro bump bonding by solder melting may be employed. Further, for example, about one bump 109 may be provided for one unit group described later. Therefore, the size of the bump 109 may be larger than the pitch of the PD 104. In addition, a bump larger than the bump 109 corresponding to the pixel region may be provided in a peripheral region other than the pixel region where the pixels are arranged (the pixel region 113A shown in FIG. 2).

  The signal processing chip 111 includes a TSV (Through-Silicon Via) 110 that connects circuits provided on the front surface and the back surface to each other. The TSV 110 is provided in the peripheral area. The TSV 110 may be provided in the peripheral area of the imaging chip 113 or the memory chip 112.

  FIG. 2 is a diagram for explaining the pixel array and the unit group 131 of the imaging chip 113. FIG. 2 particularly shows a state where the imaging chip 113 is observed from the back side. An area where pixels are arranged in the imaging chip 113 is referred to as a pixel area (imaging area) 113A. In the pixel region 113A, 20 million or more pixels are arranged in a matrix. In the example shown in FIG. 2, 16 pixels of 4 pixels × 4 pixels adjacent to each other form one unit group 131. The grid lines in FIG. 2 indicate a concept in which adjacent pixels are grouped to form a unit group 131. The number of pixels forming the unit group 131 is not limited to this, and may be about 1000, for example, 32 pixels × 64 pixels, or more or less.

  As shown in the partially enlarged view of the pixel region 113A, the unit group 131 includes four so-called Bayer arrays including four pixels of green pixels Gb and Gr, a blue pixel B, and a red pixel R in the vertical and horizontal directions. The green pixel is a pixel having a green filter as the color filter 102, and receives light in the green wavelength band of incident light. Similarly, the blue pixel is a pixel having a blue filter as the color filter 102 and receives light in the blue wavelength band. The red pixel is a pixel having a red filter as the color filter 102 and receives light in the red wavelength band.

  FIG. 3 is a circuit diagram corresponding to the unit group 131 of the imaging chip 113. In FIG. 3, a rectangle surrounded by a dotted line typically represents a circuit corresponding to one pixel. Note that at least some of the transistors described below correspond to the transistor 105 in FIG.

  As described above, the unit group 131 is formed of 16 pixels. The 16 PDs 104 corresponding to the respective pixels are each connected to the transfer transistor 302. The gate of each transfer transistor 302 is connected to a TX wiring 307 to which a transfer pulse is supplied. In the present embodiment, the TX wiring 307 is commonly connected to the 16 transfer transistors 302.

  The drain of each transfer transistor 302 is connected to the source of the corresponding reset transistor 303, and a so-called floating diffusion FD (charge detection unit) between the drain of the transfer transistor 302 and the source of each reset transistor 303 is connected to the amplifier transistor 304. Connected to the gate. The drain of each reset transistor 303 is connected to a Vdd wiring 310 to which a power supply voltage is supplied. The gate of each reset transistor 303 is connected to a reset wiring 306 to which a reset pulse is supplied. In the present embodiment, the reset wiring 306 is commonly connected to the 16 reset transistors 303.

  The drain of each amplification transistor 304 is connected to a Vdd wiring 310 to which a power supply voltage is supplied. The source of each amplification transistor 304 is connected to the drain of each corresponding selection transistor 305. The gate of each selection transistor 305 is connected to a decoder wiring 308 to which a selection pulse is supplied. In the present embodiment, the decoder wiring 308 is provided independently for each of the 16 selection transistors 305. The source of each selection transistor 305 is connected to a common output wiring 309. The load current source 311 supplies current to the output wiring 309. That is, the output wiring 309 for the selection transistor 305 is formed by a source follower. Note that the load current source 311 may be provided on the imaging chip 113 side or may be provided on the signal processing chip 111 side.

  Here, the flow from the start of charge accumulation to pixel output after the end of accumulation will be described. A reset pulse is applied to the reset transistor 303 through the reset wiring 306. At the same time, a transfer pulse is applied to the transfer transistor 302 through the TX wiring 307. As a result, the potentials of the PD 104 and the floating diffusion FD are reset.

  When the application of the transfer pulse is canceled, the PD 104 converts the incident light to be received into electric charge and accumulates it. Thereafter, when the transfer pulse is applied again without the reset pulse being applied, the charge accumulated in the PD 104 is transferred to the floating diffusion FD. As a result, the potential of the floating diffusion FD changes from the reset potential to the signal potential after charge accumulation. When a selection pulse is applied to the selection transistor 305 through the decoder wiring 308, the change in the signal potential of the floating diffusion FD is transmitted to the output wiring 309 through the amplification transistor 304 and the selection transistor 305. By such an operation of the circuit, a pixel signal corresponding to the reset potential and the signal potential is output from the unit pixel to the output wiring 309.

  As shown in FIG. 3, in the present embodiment, the reset wiring 306 and the TX wiring 307 are common to the 16 pixels forming the unit group 131. That is, the reset pulse and the transfer pulse are simultaneously applied to all 16 pixels. Therefore, all the pixels forming the unit group 131 start charge accumulation at the same timing and end charge accumulation at the same timing. However, the pixel signal corresponding to the accumulated charge is selectively output to the output wiring 309 by sequentially applying the selection pulse to each selection transistor 305. In addition, the reset wiring 306, the TX wiring 307, and the output wiring 309 are provided separately for each unit group 131.

  By configuring the circuit with the unit group 131 as a reference in this way, the charge accumulation time can be controlled for each unit group 131. In other words, pixel signals with different charge accumulation times can be output between the unit groups 131. More specifically, while one unit group 131 performs charge accumulation once, the other unit group 131 repeats charge accumulation several times and outputs a pixel signal each time, so that Each frame for moving images can be output at a different frame rate between the unit groups 131.

  FIG. 4 is a block diagram illustrating a functional configuration of the image sensor 100. The analog multiplexer 411 sequentially selects the 16 PDs 104 that form the unit group 131. Then, the multiplexer 411 outputs each pixel signal of the 16 PDs 104 to the output wiring 309 provided corresponding to the unit group 131. The multiplexer 411 is formed on the imaging chip 113 together with the PD 104.

  The analog pixel signal output through the multiplexer 411 is amplified by an amplifier 412 formed in the signal processing chip 111. Then, the pixel signal amplified by the amplifier 412 is processed by a signal processing circuit 413 that performs correlated double sampling (CDS) / analog / digital (Analog / Digital) conversion, which is formed in the signal processing chip 111. Correlated double sampling signal processing is performed, and A / D conversion (conversion from an analog signal to a digital signal) is performed. The pixel signal is subjected to correlated double sampling signal processing in the signal processing circuit 413, whereby noise of the pixel signal is reduced. The A / D converted pixel signal is transferred to the demultiplexer 414 and stored in the pixel memory 415 corresponding to each pixel. The demultiplexer 414 and the pixel memory 415 are formed in the memory chip 112.

  The arithmetic circuit 416 processes the pixel signal stored in the pixel memory 415 and passes it to the subsequent image processing unit. The arithmetic circuit 416 may be provided in the signal processing chip 111 or may be provided in the memory chip 112. Note that FIG. 4 shows connections for one unit group 131, but actually these exist for each unit group 131 and operate in parallel. However, the arithmetic circuit 416 may not exist for each unit group 131. For example, one arithmetic circuit 416 may perform sequential processing while sequentially referring to the values in the pixel memory 415 corresponding to each unit group 131.

  As described above, the output wiring 309 is provided corresponding to each of the unit groups 131. The image sensor 100 is formed by stacking an image pickup chip 113, a signal processing chip 111, and a memory chip 112. For this reason, by using the electrical connection between the chips using the bumps 109 for the output wirings 309, the wirings can be routed without enlarging each chip in the surface direction.

  Next, blocks and phase difference detection pixels set in the pixel region 113A (see FIG. 2) of the imaging chip 113 will be described. FIG. 5 is a diagram showing a pixel block (hereinafter simply referred to as a block) 200 and phase difference detection pixels 301 and 302 set in the pixel region 113A of the imaging chip 113. As shown in FIG. 5, the pixel region 113 </ b> A of the imaging chip 113 is divided into a plurality of blocks 200. The plurality of blocks 200 are defined to include at least one unit group 131 (see FIG. 2) described above per block. In each block 200, the pixels included in each block 200 are controlled by different control parameters. That is, pixel signals having different control parameters are acquired for a pixel group included in a block and a pixel group included in another block. The control parameters include, for example, charge accumulation time or accumulation count, frame rate, gain, decimation rate (pixel decimation rate), number of addition rows or addition columns (pixel addition number) for adding pixel signals, digitization bit Numbers are given. Furthermore, the control parameter may be a parameter in image processing after obtaining an image signal from a pixel.

  As shown in FIG. 5, in the pixel region 113A of the imaging chip 113, a plurality (three in this embodiment) of linear phase difference detection regions 201, 202, and 203 are provided in the horizontal direction (row direction). ing. Further, as shown in the partially enlarged view of FIG. 5, the phase difference detection areas 201, 202, and 203 each include a plurality of pairs of phase difference detection pixels 301 and 302. Each of the plurality of pairs of phase difference detection pixels 301 and 302 separates the light incident through the photographing optical system (see the photographing optical system 11 in FIG. 6 described later) in two directions with a separator lens, and produces a pair of images. Generate data. Each of the plurality of pairs of phase difference detection pixels 301 and 302 outputs a pair of image data to a system control unit 70 (see FIG. 6) described later.

  Note that a focus detection unit 71 (see FIG. 7) of the system control unit 70 to be described later performs a phase difference detection calculation on the pair of image data output from the phase difference detection pixels 301 and 302, so that a pair of A difference in image displacement (a phase difference between a pair of images) is detected. The focus detection unit 71 calculates a defocus amount (a focus shift amount, a subject blur amount) based on a difference between the pair of images. The focus detection unit 71 determines the amount of movement of the focusing lens 11c to the focal position based on the calculated defocus amount. The detection of the focal position by the phase difference detection pixels 301 and 302 provided on the image plane (pixel area 113A) of the image sensor 100 in this way is called an image plane phase difference detection method.

  In FIG. 5, in order to make the arrangement of the blocks 200 easy to see, a smaller number of blocks 200 are set in the pixel region 113 </ b> A, but a larger number of blocks 200 than the number of blocks 200 shown in FIG. It may be set in the area 113A. In FIG. 5, the phase difference detection area in which the phase difference detection pixels 301 and 302 are arranged is a three-line area in the horizontal direction, but is not in the horizontal direction (row direction) but in the vertical direction. (Column direction). The phase difference detection region may be one, two, four or more line-shaped regions.

  Next, control parameters will be described. The charge accumulation time refers to the time from when PD 104 starts to accumulate charge until it ends. In this specification, this charge accumulation time is also referred to as exposure time or shutter speed (shutter speed / electronic shutter speed). The number of times of charge accumulation refers to the number of times the PD 104 accumulates charges per unit time. The frame rate is a value representing the number of frames processed (displayed or recorded) per unit time in a moving image. The unit of the frame rate is represented by fps (Frames Per Second). The higher the frame rate, the smoother the movement of the subject (that is, the object to be imaged) in the moving image.

  The gain means a gain factor (amplification factor) of the amplifier 412. By changing this gain, the ISO sensitivity can be changed. This ISO sensitivity is a photographic film standard established by ISO and represents how much light the photographic film can record. However, generally, ISO sensitivity is also used when expressing the sensitivity of the image sensor 100. In this case, the ISO sensitivity is a value representing the ability of the image sensor 100 to capture light. Increasing the gain improves the ISO sensitivity. For example, when the gain is doubled, the electrical signal (pixel signal) is also doubled, and the brightness is appropriate even when the amount of incident light is half. However, when the gain is increased, noise included in the electric signal is also amplified, so that noise increases.

  The thinning-out rate is the ratio of the number of pixels that do not read out pixel signals with respect to the total number of pixels in a predetermined area. For example, when the thinning rate of a predetermined area is 0, it means that pixel signals are read from all pixels in the predetermined area. Further, when the thinning rate of the predetermined area is 0.5, it means that the pixel signal is read from half of the pixels in the predetermined area. Specifically, when the unit group 131 is a Bayer array, it is read as a pixel from which pixel signals are alternately read out every other unit of the Bayer array in the vertical direction, that is, every two pixels (two rows) of the pixel unit. Pixels that are not output are set. It should be noted that the resolution of the image is reduced when the pixel signal readout is thinned out. However, since 20 million or more pixels are arranged in the image sensor 100 in the present embodiment, for example, even if thinning is performed at a thinning rate of 50% (1/2 thinning), an image is captured with 10 million or more pixels. Can be displayed.

  Further, the number of added rows refers to the number of vertical pixels (number of rows) to be added when pixel signals of pixels adjacent in the vertical direction are added. Further, the number of added columns refers to the number of horizontal pixels (number of columns) to be added when pixel signals of pixels adjacent in the horizontal direction are added. Such addition processing is performed in the arithmetic circuit 416, for example. The arithmetic circuit 416 performs the process of adding the pixel signals of a predetermined number of pixels adjacent in the vertical direction or the horizontal direction, thereby obtaining the same effect as the process of reading out the pixel signals by thinning out at a predetermined thinning rate. In the addition process described above, the average value may be calculated by dividing the added value by the number of rows or columns added by the arithmetic circuit 416.

  The number of bits for digitization refers to the number of bits when the signal processing circuit 413 converts an analog signal into a digital signal in A / D conversion. As the number of bits of the digital signal increases, brightness, color change, and the like are expressed in more detail.

  In the present embodiment, the accumulation condition refers to a condition related to charge accumulation in the image sensor 100. Specifically, the accumulation condition refers to the charge accumulation time or number of accumulations, the frame rate, and the gain among the control parameters described above. Since the frame rate can change according to the charge accumulation time and the number of times of accumulation, the frame rate is included in the accumulation condition. Further, the amount of light for proper exposure changes according to the gain, and the charge accumulation time or number of times of accumulation can also change according to the amount of light for proper exposure. For this reason, the gain is included in the accumulation condition.

  In addition, in this embodiment, the accumulation condition may be referred to as an exposure condition (exposure condition) because the amount of light for proper exposure changes according to the charge accumulation time or accumulation count, the frame rate, and the gain. .

  In the present embodiment, the imaging condition refers to a condition related to imaging of a subject. Specifically, the imaging condition refers to a control parameter including the above accumulation condition. The imaging conditions include control parameters (for example, charge accumulation time or accumulation count, frame rate, gain) for controlling the image sensor 100, as well as control parameters (for controlling reading of signals from the image sensor 100). For example, a thinning rate, the number of addition rows or addition columns for adding pixel signals, and control parameters for processing signals from the image sensor 100 (for example, the number of bits for digitization, the image processing unit 30 described later performs image processing) Is also included.

  FIG. 6 is a cross-sectional view illustrating a schematic configuration of a digital camera system (imaging system) 1 that is an example of an electronic apparatus. The digital camera system 1 of this embodiment includes a lens unit 10 and a camera body 2. The lens unit 10 is an interchangeable lens. The camera body 2 is provided with a body side mount portion 80A for mounting the lens portion 10. Further, the lens unit 10 is provided with a lens side mount unit 80B corresponding to the body side mount unit 80A. When the user attaches the lens side mount portion 80B to the body side mount portion 80A, the lens portion 10 is attached to the camera body 2. When the lens unit 10 is mounted on the camera body 2, the electrical contact 81A provided on the body side mount 80A and the electrical contact 81B provided on the lens side mount 80B are electrically connected.

  The lens unit 10 includes a photographing optical system 11, a diaphragm 14, and a lens drive control device 15. The imaging optical system 11 includes a lens 11a, a zooming lens 11b, and a focusing lens 11c. The lens drive control device 15 includes a lens side CPU (Central Processing Unit), a memory, and a drive control circuit. The lens drive control device 15 is electrically connected to the system control unit 70 on the camera body 2 side via the electrical contacts 81A and 81B, and stores lens information related to optical characteristics of the photographing optical system 11 provided in the lens unit 10. Transmission and transmission / reception regarding control information for driving the zooming lens 11b, the focusing lens 11c, and the diaphragm 14 are performed.

  The lens side CPU of the lens drive control device 15 performs lens adjustment based on control information (focusing lens drive command) transmitted from the system control unit 70 in the camera body 2 in order to adjust the focus of the photographing optical system 11. The drive control circuit in the drive control device 15 is caused to execute drive control of the focusing lens 11c. The lens-side CPU of the lens drive control device 15 sends a drive control circuit in the lens drive control device 15 based on control information (zoom lens drive command) transmitted from the system control unit 70 to perform zooming adjustment. Drive control of the zooming lens 11b is executed. The diaphragm 14 is disposed along the optical axis of the photographing optical system 11. The aperture 14 forms an aperture with a variable aperture diameter at the center of the optical axis in order to adjust the amount of light and the amount of blur. The lens side CPU of the lens drive control device 15 performs drive control of the diaphragm 14 based on control information (aperture drive command) transmitted from the system control unit 70 in the camera body 2 in order to adjust the aperture diameter of the diaphragm 14. Is executed by the drive control circuit in the lens drive control device 15.

The camera body 2 includes an imaging unit 20, an image processing unit 30, a display unit 50, a recording unit 60, a light emitting unit 65, and a system control unit 70.
The imaging unit 20 includes an imaging element 100. A light beam emitted from the photographing optical system 11 of the lens unit 10 (light beam in the imaging field) enters the image sensor 100. The image sensor 100 photoelectrically converts a light beam incident on each pixel that outputs a pixel signal for generating an image to generate a pixel signal (image signal, image data) of each pixel of the image sensor. RAW data (RAW data is also included in the image data) composed of pixel signals of each pixel is sent from the imaging unit 20 to the image processing unit 30.

The image processing unit 30 performs various kinds of image processing on the RAW data including the pixel signal of each pixel, and generates image data in a predetermined file format (for example, JPEG format).
The display unit 50 displays the image data generated by the image processing unit 30.
The recording unit 60 includes a storage unit that stores a storage medium (such as a well-known memory card) that can be attached to and detached from the camera body 2, and the image processing unit 30 generates the storage medium stored in the storage unit. Recorded image data is recorded. Note that when the storage unit 60 has a built-in storage medium, the recording unit 60 can also record image data on the built-in storage medium.
The light emitting unit 65 irradiates the subject with illumination light for shooting (flash or continuous light).

  Note that “image data” may be referred to as “image signal”. The images include still images, moving images, and live view images. The live view image is an image displayed on the display unit 50 by sequentially outputting the image data generated by the image processing unit 30 to the display unit 50. The live view image is used for the user to confirm the image of the subject imaged by the imaging unit 20. The live view image is also called a through image or a preview image.

  The system control unit 70 controls the overall processing and operation of the digital camera system 1. Details of processing and operation of the system control unit 70 and details of the configuration in the camera body 2 will be described with reference to FIG.

  FIG. 7 is a block diagram showing the configuration of the digital camera system 1 according to the first embodiment. As shown in FIG. 7, the digital camera system 1 includes a camera body 2 and a lens unit 10. As described above, the lens unit 10 is an interchangeable lens that can be attached to and detached from the camera body 2. Therefore, the digital camera system 1 may not include the lens unit 10. However, the lens unit 10 may be integrated with the digital camera system 1. The lens unit 10 guides the luminous flux from the subject to the imaging unit 20 in a state where the lens unit 10 is connected to the camera body 2.

  As described above, the lens unit 10 includes the lens drive control device 15 (see FIG. 6). The lens unit 10 includes a plurality of lens groups as the photographing optical system 11, that is, a lens 11a, a zooming lens 11b, and a focusing lens 11c. When the lens unit 10 is connected to the camera body 2, the lens drive control device 15 transmits lens information stored in the memory to the system control unit 70 of the camera body 2. The lens drive control device 15 receives control information (movement amount, aperture value, etc.) transmitted from the system control unit 70 when the lens unit 10 is connected to the camera body 2. The lens drive control device 15 performs drive control of the zooming lens 11b, the focusing lens 11c, and the diaphragm 14 based on the control information. The drive control of the focusing lens 11c is control for adjusting the focus of the focusing lens 11c, and is referred to as AF processing (Automatic Focusing). The drive control of the diaphragm 14 is control for adjusting the aperture diameter of the diaphragm 14.

  As shown in FIG. 7, the camera body 2 includes an imaging unit 20, an image processing unit 30, a work memory 40, a display unit 50, an operation unit 55, a recording unit 60, and a system control unit 70.

  The imaging unit 20 includes an imaging element 100 and a drive unit 21. The drive unit 21 is a control circuit that controls driving of the image sensor 100 in accordance with an instruction from the system control unit 70. Here, the drive unit 21 controls the timing (or timing cycle) at which the reset pulse and the transfer pulse are applied to the reset transistor 303 and the transfer transistor 302, respectively, thereby reducing the charge accumulation time or accumulation count as a control parameter. Control. In addition, the drive unit 21 controls the frame rate by controlling the timing (or timing cycle) at which the reset pulse, the transfer pulse, and the selection pulse are applied to the reset transistor 303, the transfer transistor 302, and the selection transistor 305, respectively. To do. The drive unit 21 controls the thinning rate by setting pixels to which the reset pulse, the transfer pulse, and the selection pulse are applied.

  In addition, the drive unit 21 controls the ISO sensitivity of the image sensor 100 by controlling the gain (also referred to as gain factor or amplification factor) of the amplifier 412. In addition, the driving unit 21 sends an instruction to the arithmetic circuit 416 to set the number of added rows or the number of added columns to which the pixel signals are added. Further, the drive unit 21 sets the number of bits for digitization by sending an instruction to the signal processing circuit 413. Furthermore, the drive unit 21 sets areas in units of blocks in the pixel area (imaging area) 113 </ b> A of the image sensor 100. In this way, the drive unit 21 functions as an image sensor control unit that causes the image sensor 100 to capture an image under different image capturing conditions for each of a plurality of blocks and output a pixel signal. The system control unit 70 instructs the drive unit 21 on the block position, shape, range, and the like.

  The image sensor 100 delivers the pixel signal from the image sensor 100 to the image processing unit 30. The image processing unit 30 uses the work memory 40 as a work space, performs various image processing on the RAW data including pixel signals of each pixel, and generates image data in a predetermined file format (for example, JPEG format). . The image processing unit 30 executes the following image processing. For example, the image processing unit 30 generates an RGB image signal by performing color signal processing (color tone correction) on a signal obtained by the Bayer array. The image processing unit 30 performs image processing such as white balance adjustment, sharpness adjustment, gamma correction, and gradation adjustment on the RGB image signal. Further, the image processing unit 30 performs a process of compressing in a predetermined compression format (JPEG format, MPEG format, etc.) as necessary. The image processing unit 30 outputs the generated image data to the recording unit 60. In addition, the image processing unit 30 outputs the generated image data to the display unit 50.

  Parameters that are referred to when the image processing unit 30 performs image processing are also included in the control parameters (imaging conditions). For example, parameters such as color signal processing (tone correction), white balance adjustment, gradation adjustment, and compression rate are included in the control parameters. The signal read from the image sensor 100 changes according to the charge accumulation time, and the parameters referred to when performing image processing also change according to the change in the signal. The image processing unit 30 sets different control parameters for each block 200 and executes image processing such as color signal processing based on these control parameters.

  In the present embodiment, the image processing unit 30 includes a subject detection unit 31. The subject detection unit 31 detects the shape of the subject and the presence position in the two-dimensional plane (in the imaging plane) from the image data generated by the image processing unit 30. The subject detection unit 31 detects a human body included in image data as a subject, as described in, for example, Japanese Patent Application Laid-Open No. 2010-16621 (US2010 / 0002940). Note that the subject detection unit 31 may detect a human face as a subject using a known face detection function. The subject detection unit 31 may have a function of detecting a moving subject (moving subject) by comparing a plurality of image data (frames) obtained in time series from the image processing unit 30. The subject detection unit 31 may have a function of detecting the subject by specifying the boundary of the subject based on the contrast and color change between the bright part and the dark part in the image data.

  Here, the subject that is an object to be imaged by the imaging unit 20 is not limited to a single object in the image data, and there may be a plurality of objects. Further, among the subjects, a subject that is noticed by the user (photographer) or a subject that is estimated to be noticed by the user is referred to as a “main subject”. The number of main subjects is not limited to one in the image data, and there may be a plurality of main subjects.

  The work memory 40 temporarily stores image data and the like when image processing by the image processing unit 30 is performed. The display unit 50 displays images (still images, moving images, live view images) and various types of information captured by the imaging unit 20. The display unit 50 includes a display panel such as a liquid crystal display panel. A touch panel 51 is formed on the display panel of the display unit 50. The touch panel 51 outputs a signal indicating a position touched by the user to the system control unit 70 when the user performs an operation such as menu selection.

  The operation unit 55 is a release switch (a switch that is pressed when shooting a still image), a moving image switch (a switch that is pressed when shooting an operation), various operation switches, and the like that are operated by the user. The operation unit 55 outputs a signal corresponding to the operation by the user to the system control unit 70. As described above, the recording unit 60 has a card slot into which a storage medium such as a memory card can be mounted. The recording unit 60 records the image data generated by the image processing unit 30 and various data on a storage medium mounted in the card slot. Further, when the camera body has an internal memory, the recording unit 60 can also record the image data and various data generated by the image processing unit 30 in the internal memory.

  In this embodiment, the light emitting unit 65 is a light emitting device (illuminating device) that emits (illuminates) illumination light (flash or continuous light) that illuminates a subject when photographing. The light emitting unit 65 includes a light source 65A and a light emission control unit 65B as shown in FIG. The light source 65A is configured by a xenon lamp, an LED (Light Emitting Diode), or the like. A xenon lamp is a lamp that utilizes light emission by discharge in xenon gas. An LED is a semiconductor element that emits light based on application of a voltage. The light emission control unit 65B performs control to cause the light source 65A to emit light with a predetermined light amount based on an instruction signal from the system control unit 70. The digital camera system 1 includes a sensor (not shown) that detects the brightness around the digital camera system 1, for example. Then, the system control unit 70 determines whether or not the surroundings of the digital camera system 1 are darker than a predetermined darkness based on the detection signal from the sensor. When the system controller 70 determines that the periphery of the digital camera system 1 is darker than the predetermined darkness when capturing an image of the subject, the system controller 70 outputs a light emission instruction signal to the light emitter 65 when performing the image capturing operation. By outputting, illumination light is emitted to the light emitting unit 65 simultaneously with imaging. In addition, the system control unit 70 causes the light emitting unit 65 to emit illumination light by outputting a light emission instruction signal to the light emitting unit 65 in accordance with an operation (manual light emission operation) of the operation unit 55 by the user.

  The system control unit 70 controls the overall processing and operation of the digital camera system 1. The system control unit 70 has a body side CPU (Central Processing Unit). In the present embodiment, the system control unit 70 divides the imaging surface (pixel region 113A) of the imaging device 100 (imaging chip 113) into a plurality of blocks 200, and different charge accumulation times (for each block) (for each block). Alternatively, an image can be acquired with the number of charge accumulations), a frame rate, and a gain. At that time, the system control unit 70 instructs the drive unit 21 to set the position, shape, range, and accumulation condition for each block on the imaging surface (on the pixel area 113A) of each block.

Further, the system control unit 70 can also acquire images with different thinning rates between blocks (for each block), the number of added rows or added columns to which pixel signals are added, and the number of digitization bits. . At that time, the system control unit 70 instructs the drive unit 21 to set the imaging conditions for each block (thinning rate, number of added rows or columns to add pixel signals, and number of digitization bits). Let
The image processing unit 30 can execute image processing under different imaging conditions (control parameters such as color signal processing, white balance adjustment, gradation adjustment, and compression rate) between blocks (for each block). . At that time, the system control unit 70 instructs the image processing unit 30 to set the imaging conditions for each block (control parameters such as color signal processing, white balance adjustment, gradation adjustment, and compression rate).

Further, the system control unit 70 causes the recording unit 60 to record the image data generated by the image processing unit 30.
Further, the system control unit 70 causes the display unit 50 to display the live view image by causing the display unit 50 to output the image data generated in the image processing unit 30 before the recording unit 60 records the image data. Further, the system control unit 70 reads out image data recorded in a storage medium housed in the recording unit 60 and outputs the image data to the display unit 50, thereby recording images (still images and moving images) on the display unit 50. Is displayed.

  In the present embodiment, the system control unit 70 includes a focus detection unit (distance detection unit) 71 and a control unit 72 as shown in FIG. The focus detection unit 71 performs a focus adjustment process (AF process) on a subject existing in the imaging field based on the half-press operation of the release switch by the user. Specifically, the focus detection unit 71 detects the phase difference between the pair of images by performing a phase difference detection calculation on the pair of image data output from the phase difference detection pixels 301 and 302. The focus detection unit 71 calculates the defocus amount based on the phase difference between the pair of images. Based on the calculated defocus amount, the focus detection unit 71 determines the amount of movement from the current focus position of the focusing lens 11c to the focus position (focus position) at which the focusing lens 11c focuses on the subject. . The focus detection unit 71 transmits a control signal indicating the determined movement amount to the lens drive control device 15 via the electrical contacts 81A and 81B. Thus, the lens drive control device 15 executes drive control for moving the focusing lens 11c to the focus position based on the control information from the focus detection unit 71.

  Here, the focus detection unit 71 calculates the defocus amount for each of the plurality of subjects when the subject detection unit 31 detects a plurality of subjects in the imaging field of view (detects the position of the subject in the two-dimensional plane). To do. The calculation of the defocus amount for each subject is performed using the outputs of the phase difference detection pixels 301 and 302 arranged at positions corresponding to (overlapping) each subject image.

  In the case where the distances (existing position / subject distance / photographing distance in the optical axis direction of the lens included in the lens unit 10) of the plurality of subjects in the imaging field are different from each other (photographing scene). For example, the focus detection unit 71 controls to focus on the subject closest to the digital camera system 1 among the plurality of subjects. That is, for example, the focus detection unit 71 reaches the in-focus position of the focusing lens 11c based on the defocus amount with respect to the subject closest to the digital camera system 1 (hereinafter referred to as the closest subject) among the plurality of subjects. Determine the amount of movement. Then, the focus detection unit 71 transmits a control signal indicating the determined movement amount to the lens drive control device 15. When the lens drive controller 15 drives the focusing lens 11c to the in-focus position based on this control signal, an image focused on the closest subject can be obtained. For example, consider a case where a plurality of human photographs (group photographs, etc.) arranged in front and rear in the direction of the optical axis of the camera are captured. The closest subject (person A) and the person B, who is a subject (hereinafter referred to as a far subject) located farther from the camera system 1 than the closest subject, person A, are about 1 m away from each other. In some cases, an image focused on both subjects can be obtained with such a distance difference.

  The control unit 72 sets an imaging condition (for example, an initial imaging condition) at the time of capturing a live view image. And the control part 72 performs drive control of the image pick-up element 100 so that it may image on the imaging conditions at the time of imaging of a live view image. That is, the control unit 72 outputs an instruction signal for instructing imaging conditions such as a frame rate and gain (ISO sensitivity) at the time of capturing a live view image to the drive unit 21. The drive unit 21 drives and controls the image sensor 100 under the imaging condition specified by the instruction signal.

The control unit 72 detects a subject (for example, a subject detected by the subject detection unit 31 in the imaging field of view in the pixel region (imaging region) 113A of the imaging device 100 based on the half-press operation of the release switch by the user. A subject area including a person (see, for example, subject areas 511 and 512 in FIG. 11B) is set in units of 200 pixel blocks on the image sensor. At this time, when the subject detection unit 31 detects a plurality of subjects, the control unit 72 sets a subject area for each of the plurality of subjects.
In FIG. 11, rectangular subject areas 511 and 512 are set, but shapes other than the rectangular shape (such as an ellipse) may be used. Alternatively, each subject area may be set according to the shape of the subject (a person in the present embodiment). When setting following the subject shape, the setting may be made based on the result of the camera body 2 analyzing the image and automatically recognizing the subject shape, or the subject area can be touched by the user on the touch panel. May be input and set.

  The control unit 72 acquires the defocus amount for the subject calculated by the focus detection unit 71 based on the fact that the user has fully pressed the release switch. Then, the control unit 72 calculates (estimates) the distance to the subject based on the defocus amount for the subject. At this time, when the subject detection unit 31 detects a plurality of subjects, the control unit 72 acquires a defocus amount for each of the plurality of subjects, and calculates a distance to each of the plurality of subjects based on the acquired defocus amount. (presume.

  The control unit 72 determines an imaging condition (shutter speed, gain, etc.) and an aperture value so that the subject is properly exposed, based on the fact that the user has fully pressed the release switch. Specifically, when the release switch is fully pressed, the control unit 72 is not for recording on the storage medium, but based on the image signal captured to acquire the luminance information, Luminance distribution data (luminance data in pixel units) indicating the luminance distribution is acquired from the image processing unit 30. Then, the control unit 72 performs photometry using the luminance distribution data. Further, the control unit 72 determines imaging conditions such as a shutter speed (charge accumulation time and exposure time) and imaging sensitivity (gain), and an aperture value based on the photometric result. At this time, the control unit 72 can determine an imaging condition that provides proper exposure for each block in the pixel region 113 </ b> A of the imaging device 100. The aperture value cannot be set for each block and is set for the entire pixel area 113A.

  In addition, in the case where the light emitting unit 65 emits illumination light at the time of imaging, the control unit 72 also determines the amount of illumination light emitted to the light emitting unit 65 in addition to the imaging conditions and the aperture value that provide proper exposure. To do. Specifically, the control unit 72 determines an imaging condition and an aperture value that provide appropriate exposure as described above. Further, the control unit 72 also determines the amount of light to be emitted by the light emitting unit 65 based on the imaging conditions (in this case, gain) and the aperture value and the distance to the subject so as to achieve proper exposure. The details of the method for determining the light amount of the light emitting unit 65 will be described later (see formula (1) described later).

  Further, the control unit 72 causes the light emitting unit 65 to emit illumination light during imaging, and if the subject detection unit 31 detects a plurality of subjects, at least one of the plurality of subjects is too bright. In other words, for each of a plurality of subjects, in other words, for each of the subject regions 511 and 512 set for each of the plurality of subjects (more precisely, imaging corresponding to each of the subject regions 511 and 512) Each pixel on the element) is adjusted (individually set) imaging conditions. For example, the control unit 72 determines an imaging condition and an aperture value that provide appropriate exposure as described above, and a light emission amount of illumination light emitted from the light emitting unit 65. After that, the control unit 72 sets the exposure for the plurality of subjects to the appropriate exposure (predetermined amount of exposure) according to the amount of light emitted from the light emitting unit 65 based on the distance for each of the plurality of subjects. The imaging condition of the subject area is adjusted. As an example, the imaging condition of the subject area for each of the plurality of subjects is adjusted so that the exposure amount for the plurality of subjects is uniform (equal) or substantially uniform among the subjects. Details of how to determine the imaging conditions for each subject area will be described later.

  The control unit 72 outputs an instruction signal for instructing the light amount of the illumination light (light emission amount) to the light emitting unit 65. The light emission control unit 65B of the light emitting unit 65 performs control to cause the light source 65A to emit light with the light amount instructed by the instruction signal. In addition, the control unit 72 transmits control information indicating the aperture value to the lens drive control device 15. The lens drive control device 15 executes drive control for adjusting the aperture diameter of the diaphragm 14 based on control information from the control unit 72. Further, the control unit 72 outputs an instruction signal for instructing imaging conditions such as a shutter speed and a gain to the driving unit 21. The drive unit 21 drives and controls the image sensor 100 under the imaging condition specified by the instruction signal.

  In the system control unit 70, the focus detection unit 71 and the control unit 72 are realized by the body side CPU executing processing based on the control program.

  Next, an outline of the present system will be described with reference to FIGS. FIG. 8 is a diagram showing a positional relationship between the digital camera system 1 and the first subject O1 and the second subject O2. In the example shown in FIG. 8, the person O1 as the first subject is at a position closer to the digital camera system 1 (subject distance, shooting distance) in the optical axis direction of the lens unit 10 than the person O2 as the second subject. Exists. In this case, the person O1 is the closest subject and the person O2 is the far subject.

  FIG. 9 is a graph showing the relationship between the subject distance and the amount of light reached by the illumination light emitted from the light emitting unit 65. As shown in FIG. 9, the amount of illumination light emitted from the light emitting unit 65 gradually decreases as the distance from the light emitting unit 65 (subject distance) increases. Specifically, the amount of light reaching the illumination light emitted from the light emitting unit 65 decreases in inverse proportion to the square of the distance from the light emitting unit 65. Therefore, for example, when the person O1 and the person O2 exist at different positions from the light emitting unit 65 as shown in FIG. 8, the brightness of the person O2 when light is irradiated by the illumination light from the light emitting unit 65 (Illuminance) is darker than the person O1.

FIG. 10 is a graph showing the relationship between the elapsed time since the light emitting unit 65 emitted light and the amount of light emitted from the light emitting unit 65.
When a xenon tube (Xe tube) is used as the light source 65A of the light emitting unit 65, the xenon tube uses discharge in xenon gas, as indicated by “Xenon tube” in FIG. The amount of light emission decreases with time.
On the other hand, when an LED is used for the light source 65A of the light emitting unit 65, as shown by “LED” in FIG. 10, the LED can control the light emission amount according to the voltage value to be applied. The light emission amount can be controlled to be constant regardless of the passage of time (the predetermined light emission amount can be controlled to be constant for a predetermined time).
In the present embodiment, a light source whose light emission amount changes (decreases) with time, such as a xenon tube, is referred to as a first light source. A light source such as an LED that can control the amount of light emission regardless of the passage of time is called a second light source. The light source 65A may be either the first light source or the second light source.

  In the present embodiment, photographing (imaging) by causing the light emitting unit 65 to emit light may be referred to as auxiliary light photographing (auxiliary light imaging).

FIG. 11 is a diagram illustrating examples of images 501 and 502 obtained by photographing the first subject O1 and the second subject O2 with the digital camera system 1 according to the first embodiment.
FIG. 11A shows a case where the light emitting unit 65 emits illumination light to capture an image, and when the subject detection unit 31 detects a plurality of subjects (the person O1 and the person O2 in FIG. 8), the control unit 72 shows an image 501 when auxiliary light imaging is performed under a common (a set of) imaging conditions regardless of the subject area without individually (independently) adjusting the imaging conditions of the plurality of subject areas 511 and 512. Is shown.

As shown in FIG. 8, the person O2 is farther away from the digital camera system 1 than the person O1 (L1 <L2). For this reason, as described above, the brightness of the person O2 when illuminated by the light emitting unit 65 is darker than the person O1. As described above, the control unit 72 is based on the luminance distribution data acquired from the image processing unit 30 before the light emitting unit 65 emits light (photometric data obtained from an imaging signal captured without illumination light irradiation). Imaging conditions such as shutter speed, imaging sensitivity (gain), aperture value, and the like are determined.
Next, the control unit 72 uses a predetermined calculation method (formula (1) described later) to illuminate the light from the light emitting unit 65 with the aperture value, gain, and distance L1 to the person O1 determined when the imaging condition is set as a reference. Determine the amount of light emitted (guide number). When imaging is performed with such imaging conditions and the amount of light emitted from the light emitting unit 65, the image of the person O1 in the subject area 511 is an image with appropriate exposure, as an image 501 shown in FIG. The image of the person O2 is darker than the image of the person O1.

  Note that the control unit 72 determines imaging conditions such as a shutter speed, imaging sensitivity (gain), aperture value, and the like with appropriate exposure based on the luminance information for the person O2, and the light emitting unit 65 based on the distance L2 for the person O2. When the amount of emitted light is determined, the image of the person O2 is an image with appropriate brightness, but the image of the person O1 is too bright.

  FIG. 11B shows a case where auxiliary light imaging is performed with illumination light from the light emitting unit 65, and the control is performed when the subject detection unit 31 detects a plurality of subjects (the person O1 and the person O2 in FIG. 8). An image 502 is shown when the unit 72 performs auxiliary light imaging by independently adjusting the imaging conditions of the plurality of subject areas 511 and 512. As described above, the brightness of the person O2 when illuminated by the light emitting unit 65 is darker than the person O1. Therefore, the control unit 72 performs imaging by individually adjusting the imaging conditions of the subject areas 511 and 512 so that the image of the person O2 does not become a dark image.

Specifically, the control unit 72 emits light from the light emitting unit 65 based on the distance L1 from the digital camera system 1 (that is, the light emitting unit 65) to the person O1 and the distance L2 from the digital camera system 1 to the person O2. Accordingly, the exposure amount of the person O2 is calculated (estimated) so as to be uniform (same) or substantially uniform (substantially the same) as the exposure amount for the person O1. Then, the control unit 72 adjusts the shutter speed and gain of the subject area 512 including the person O2 based on the calculated exposure amount of the person O2. For example, the control unit 72 can control the shutter speed of the subject area 512 to be longer (slower) than the shutter speed of the subject area 511, thereby brightening the image of the person O2. Alternatively, the control unit 72 can control the gain of the subject area 512 to be higher than the gain in the subject area 511, thereby making the image of the person O2 brighter. Alternatively, both the shutter speed and gain of the subject area 512 may be controlled simultaneously or in time series.
The control unit 72 drives and controls the image sensor 100 (pixels in the subject areas 511 and 512) with the shutter speed and gain adjusted in this way during auxiliary light imaging. By controlling in this way, the person O1 is captured with appropriate exposure as in the image 502 shown in FIG. 11B, and the image of the person O2 has the same or substantially the same brightness as the image of the person O1. According to such a configuration, the digital camera system 1 can capture images with appropriate brightness for each of the plurality of subjects O1 and O2.

  As shown in FIG. 10 described above, when the light source 65A of the light emitting unit 65 is a xenon tube (first light source), the amount of light decreases with time. In this case, even if the control unit 72 changes the shutter speed of the subject area 512, the brightness of the image of the person O2 may not change. That is, if the amount of light emitted from the light emitting unit 65 decreases in a time (interval) shorter than the shutter speed, even if the shutter speed in the pixel of the subject region 512 is set to be slow (long shutter speed). The effect of increasing the amount of exposure for the subject area 512 cannot be obtained. Therefore, when the light source 65A is a xenon tube, the control unit 72 adjusts the gain of the image of the person O2 (exposure amount) by adjusting the gain, not the shutter speed, among the imaging conditions of the pixels in the subject region 512. Adjust.

  On the other hand, as shown in FIG. 10 described above, a case where the light source 65A of the light emitting unit 65 is an LED (second light source) that emits continuous light will be described. In the LED, the amount of illumination light does not change with time. In this case, the control unit 72 can change the brightness of the image of the person O2 by changing the shutter speed among the imaging conditions of the pixels in the subject area 512. Therefore, the control unit 72 can adjust the brightness of the image of the person O2 by adjusting the shutter speed as the imaging condition of the subject region 512. When the light source 65A is an LED, the control unit 72 can also adjust the brightness of the image of the person O2 by adjusting the gain of the subject region 512 in the same manner as when the light source 65A is a xenon tube lamp. . Therefore, when the light source 65A is an LED, the control unit 72 adjusts the brightness of the image of the person O2 by adjusting at least one of the gain and the shutter speed as the imaging condition of the subject region 512. For example, in the case of tripod photography where camera shake is unlikely to occur, the shutter speed may be adjusted instead of gain to reduce gain noise caused by increasing gain, and gain noise is relatively conspicuous. In the case of a shooting scene in which there is no shooting scene but is likely to cause camera shake or subject blur (for example, when a moving subject is shot by hand), the gain may be adjusted.

Next, the photographing operation of the digital camera system 1 will be described.
FIG. 12 is a flowchart for explaining a photographing operation executed by the system control unit 70 of the first embodiment. In the processing shown in FIG. 12, after the user turns on the digital camera system 1, when the user operates the operation unit 55 or the like to start shooting, the control unit 72 causes the live view image to be captured. Imaging of a live view image is started under imaging conditions (initial imaging conditions) (step S1). That is, the control unit 72 causes the drive unit 21 to execute the drive control of the image sensor 100 based on the initial value imaging condition by outputting an instruction signal instructing the initial value imaging condition. Then, the system control unit 70 displays the live view image captured by the image sensor 100 on the display screen of the display unit 50 (step S2).

  Thereafter, the system control unit 70 determines whether or not a release switch half-press operation (SW1 operation) has been performed (step S3). The system control unit 70 repeatedly executes the processes of step S1 and step S2 until the release switch is half-pressed. If the system control unit 70 determines that the half-press operation of the release switch has been performed, the control unit 72 continues to capture the live view image under the imaging conditions at the time of capturing the live view image (step S4). Further, the system control unit 70 displays the live view image captured by the image sensor 100 on the display screen of the display unit 50 (step S5).

  Next, in step S <b> 6, the control unit 72 outputs an instruction signal to the image processing unit 30 to cause the subject detection unit 31 to detect the subject. Upon receiving the instruction signal from the control unit 72, the subject detection unit 31 detects a person (human body) included in the image data as a subject. For example, the subject detection unit 31 detects the person O1 and the person O2 shown in FIGS. 11A and 11B as subjects. Then, the subject detection unit 31 outputs a signal indicating the position and size of the detected person O1 and person O2 to the system control unit 70. Based on the signals indicating the positions and sizes of the person O1 and the person O2 from the subject detection unit 31, the control unit 72 includes a subject area 511 including the person O1 and a subject area including the person O2 as illustrated in FIG. 512 is set for each block.

  Next, in step S <b> 7, the focus detection unit 71 performs AF processing. That is, the focus detection unit 71 detects a phase difference between a pair of images by performing a phase difference detection calculation on the pair of image data output from the phase difference detection pixels 301 and 302 (see FIG. 5). . The focus detection unit 71 may be configured to receive a pair of image data output from the phase difference detection pixels 301 and 302 directly from the image sensor 100, or may be configured to receive the image data via the image processing unit 30. Also good. The focus detection unit 71 calculates the defocus amount based on the phase difference between the pair of images. At this time, when the subject detection unit 31 detects the person O1 and the person O2, the focus detection unit 71 calculates the defocus amount of the person O1 and the defocus amount of the person O2.

  The focus detection unit 71 determines the amount of movement of the focusing lens 11c to the in-focus position based on the defocus amount (for example, the defocus amount with respect to the person O1). The focus detection unit 71 transmits a control signal indicating the determined movement amount to the lens drive control device 15 via the electrical contacts 81A and 81B. The lens drive control device 15 executes drive control for moving the focusing lens 11 c to the in-focus position based on control information from the focus detection unit 71.

Thereafter, the system control unit 70 proceeds to step S8 and determines whether or not a full-press operation (SW2 operation) has been performed following a half-press operation of the release switch. If the system control unit 70 determines that the release switch has not been fully pressed, the processes from step S3 to step S7 are repeated.
In step S8, when the system control unit 70 determines that the release switch has been fully pressed, the control unit 72 proceeds to step S10, and the defocus amount and person of the person O1 calculated by the focus detection unit 71 are determined. The defocus amount of O2 is acquired as distance information. Further, as described above, luminance distribution data (luminance information) is acquired based on the image signal. Then, the control unit 72 calculates distance information for the person O1 based on the defocus amount for the person O1. Further, the control unit 72 calculates distance information for the person O2 based on the defocus amount for the person O2.

The control unit 72 proceeds to step S11 and executes dimming calculation for each region (for each of the subject regions 511 and 512) based on the luminance distribution data acquired in step S10 and the distance information with respect to the person O1 and the person O2. To do.
Specifically, the control unit 72 first determines a condition for obtaining an appropriate exposure for the person O1 who is the closest subject, and the luminance corresponding to the person O1 (or corresponding to the subject region 511) from the image processing unit 30. Get distribution data. Then, based on the result (Bv) of photometry using the luminance distribution data (luminance information), the control unit 72 captures images such as a shutter speed (Tv) and a gain (Sv) that allow the person O1 to be properly exposed. The conditions and the aperture value are determined by a so-called APEX calculation (Ev = Tv + Av, Ev = Sv + Bv).

  Since this sequence is a sequence for performing auxiliary light imaging, the control unit 72 performs this exposure calculation. Further, the control unit 72 determines the amount of illumination light emitted to the light emitting unit 65 based on the gain value and aperture value of the appropriate exposure determined by the exposure calculation and the distance information with respect to the person O1 and the person O2. This is determined using a predetermined arithmetic expression (the following expression (1)) stored in advance in the control unit 72 of the camera body 2. Specifically, there is a relationship as shown in the following formula (1) among the guide number (Gno), aperture value (F value), distance (shooting distance), and gain value (ISO sensitivity).

Gno = F value × distance ÷ (ISO / 100) ^1/2 (1)

Here, the guide number (Gno) is a numerical value representing the light quantity of the light emitting unit 65 (strobe). ISO indicates a gain value. Further, (ISO / 100) ^1/2 represents the square root (root) of (ISO / 100). In general, the guide number is expressed assuming that the gain value is 100. However, the guide number may be assumed assuming that the gain value is not 100. As shown in the above formula (1), the control unit 72 determines the aperture value and gain value of the appropriate exposure and the subject (here, the person O1 who is the closest subject) from the digital camera system 1 (that is, the light emitting unit 65). ), The guide number (light quantity of the light emitting unit 65) for the person O1 can be obtained.
As described above, the amount of emitted light, an imaging condition such as a shutter speed and a gain, and an aperture value that can obtain an appropriate exposure for the person O1 (or the subject area 511) are determined.

Next, the control unit 72 determines an imaging condition such that proper exposure can be obtained even for the person O2 existing in the subject area 512 when the auxiliary light imaging is performed with the guide number.
Specifically, the control unit 72 substitutes the distance L2 from the digital camera system 1 to the person O2, the guide number (Gno) and the aperture value (F value) obtained above into the above equation (1). Thus, the gain (ISO) is calculated.

  A person whose gain value for the person O2 (subject area 512) is uniform or substantially uniform with the exposure amount for the person O1 when auxiliary light photographing is performed using the illumination light with the guide number obtained above. This is the gain value for O2. Thus, the control unit 72 adjusts the brightness value of the person O2 so that the brightness of the image of the person O2 is the same as or substantially the same as the brightness of the image of the person O1.

In addition, the control unit 72 may adjust the brightness of the image of the person O2 to be the same as or substantially the same as the brightness of the image of the person O1 by adjusting the shutter speed for the person O2. In this case, the control unit 72 converts the gain value for the person O2 calculated as described above into a shutter speed for the person O2.
Specifically, the control unit 72 acquires luminance distribution data corresponding to the person O2 (or corresponding to the subject region 512) from the image processing unit 30. Then, the control unit 72 performs photometry using the luminance distribution data (luminance information) (photometric value Bv), and the gain value (Sv) for the person O2 calculated using the equation (1) as described above. And the aperture value (F value) (Av) of the appropriate exposure obtained as described above (obtained for the person O1) is applied to the above APEX calculation to calculate the shutter speed (Tv) for the person O2. To do.

  Note that the control unit 72 may use the gain value and the shutter speed to adjust the exposure amount for the person O2 to be uniform or substantially uniform with the exposure amount for the person O1 in accordance with the light amount of the light emitting unit 65. . Also in this case, the control unit 72 obtains the result (photometric value Bv) obtained by performing photometry using the luminance distribution data (luminance information) corresponding to the person O2 (or corresponding to the subject region 512) (as described above). The aperture value (F value) (Av) of appropriate exposure (obtained for the person O1) and the gain value (Sv) for the person O2 calculated using the above formula (1) are applied to the above APEX calculation. A plurality of combinations of gain values and shutter speeds for the person O2 are calculated. In this way, a plurality of combinations of gain (SV) and shutter speed (TV) for the pixels of the subject area 512 (person O2) are calculated, and any one of the combinations is selected as appropriate according to the shooting scene. Adjust both the shutter speed and the gain.

Next, in step S12, the control unit 72 sets the guide number, aperture value, and imaging conditions (for each of the subject areas 511 and 512) for each area (gain, shutter speed, etc.) determined in step S11.
In step S13, the control unit 72 outputs an instruction signal instructing the amount of light represented by the guide number determined in step S11 to the light emitting unit 65, so that the light emitting unit 65 emits illumination light (this is the main signal). Light emission).

  Subsequently, in step S14, the control unit 72 executes still image capturing processing. That is, the control unit 72 outputs a control signal indicating the aperture value determined in step S <b> 11 to the lens drive control device 15. The lens drive control device 15 executes drive control for adjusting the aperture diameter of the diaphragm 14 based on a control signal from the control unit 72. Further, the control unit 72 outputs an instruction signal for instructing the imaging conditions (gain, shutter speed, etc.) for each region (subject regions 511, 512) determined in step S11 to the drive unit 21. The drive unit 21 drives and controls the image sensor 100 under imaging conditions such as a gain and a shutter speed indicated by the instruction signal. By performing such an imaging process (step S14), a still image in which the image of the person O1 and the image of the person O2 have appropriate brightness is captured.

  In addition, as a method for obtaining the imaging condition of a pixel corresponding to a region other than the subject regions 511 and 512 (for example, a pixel corresponding to a hatched region in FIG. 11B), the region (hereinafter referred to as a third region) Various methods can be considered depending on the situation. For example, when the third subject is present in the third region, the same method as the method for obtaining the imaging condition for the subject region 512 described above (distance information to the third subject existing in the third region and What is necessary is just to obtain | require an imaging condition using the brightness | luminance information of a 3rd to-be-photographed object, the said Formula (1), and the method using APEX calculation). The third subject described above is assumed to be present at a position where the illumination light from the light emitting unit reaches.

  In addition, when the third subject does not exist in the third region, for example, the imaging may be performed using the same imaging condition as the imaging condition of any one of the subject regions 511 and 512, Alternatively, an intermediate value (for example, an average value) of the imaging conditions in the subject areas 511 and 512 may be used as the imaging conditions. Alternatively, among the imaging conditions in the third area, the shutter speed Tv is set to be the same as the imaging conditions in any of the subject areas 511 and 512, and the gain is based on the luminance information in the third area and the above APEX calculation. The condition may be set according to the luminance information.

  In step S <b> 14, the image processing unit 30 receives RAW data including pixel signals of each pixel generated by the image sensor 100. Then, the image processing unit 30 performs various image processing on the RAW data. At this time, the image processing unit 30 performs white balance adjustment of the image for each of the subjects O1 and O2 having different imaging conditions (gain and shutter speed) based on the instruction signal from the control unit 72.

  FIG. 13 is a diagram illustrating an example of an image 503 for explaining white balance adjustment by the image processing unit 30 according to the first embodiment. When the image sensor 100 captures images under different imaging conditions (gain, shutter speed) between the person O1 and the person O2 as in the image 503 illustrated in FIG. 13, the white of the image of the person O1 and the image of the person O2 is white. The difference in balance increases. For example, the ratio of the amount of light from the light emitting unit 65 to the amount of external light (for example, natural light or light from a fluorescent lamp) is 2: 1 (2: 1) for the person O1, and the light emitting unit is for the person O2. Assume that the ratio of the amount of light from 65 to the amount of external light is 1: 2 (1: 2). The color changes between the image of the person O1 and the image of the person O2. Further, as described above, when the control unit 72 adjusts the gain and shutter speed for the person O2 so that the brightness of the image of the person O1 and the image of the person O2 are the same, the image 503 shown in FIG. Thus, the difference in color between the image of the person O1 and the image of the person O2 increases. Therefore, the image processing unit 30 eliminates (reduces) the color difference between the image of the person O1 and the image of the person O2, and the image data of the person O1 (image data of the subject area 511) and the image of the person O2. White balance adjustment is performed using control parameters that differ depending on the data (image data of the subject region 512).

When the control unit 72 increases the gain for the person O2 so that the brightness of the image of the person O1 and the image of the person O2 are the same, the noise of the image of the person O2 increases. Therefore, the control unit 72 outputs the noise information of the person O2 (subject region 512) having a high gain to the image processing unit 30 in advance. The image processing unit 30 executes noise removal processing on the image data of the person O2 (image data of the subject area 512) based on the noise information from the control unit 72. The image processing unit 30 also appropriately executes other image processing in accordance with the image data of the person O1 and the image data of the person O2.
In step S14, the image signal subjected to the image processing as described above is stored in a non-volatile storage medium such as a memory card in the recording unit 60.

  In the first embodiment described above, the control unit 72 determines an appropriate light amount for the person O1 on the digital camera system 1 side as the light amount of the light emitting unit 65, and the person O2 that becomes darker than the person O1. The gain was increased or the shutter speed was increased (slow). However, the control unit 72 determines an appropriate light amount for the person O2 far from the digital camera system 1 as the light amount of the light emitting unit 65, and lowers the gain of the person O1 that becomes brighter than the person O2, or the shutter speed. May be shortened (faster).

  Further, the control unit 72 determines an appropriate light amount for the intermediate distance between the person O1 and the person O2 as the light amount of the light emitting unit 65, and sets the gain or shutter speed of the person O1 according to the light amount of the light emitting unit 65. In addition to the adjustment, the gain or shutter speed of the person O2 may be adjusted. As described above, the control unit 72 adjusts the exposure of the plurality of subjects using the light amount of the light emitting unit 65 and the imaging conditions (gain, shutter speed) as parameters, thereby adjusting the brightness of the images of the plurality of subjects to appropriate brightness. Easy to adjust.

  In the first embodiment described above, the case where the digital camera system 1 captures two persons (person O1 and person O2) as subjects has been described as an example. However, the digital camera system 1 includes three or more persons. Even when shooting, it is possible to adjust the brightness of each person's image. Further, when the digital camera system 1 captures three or more persons, the brightness of the image may be adjusted and photographed with respect to an arbitrary plurality of persons among the three or more persons. Further, although a person has been described as an example of a subject, an object other than a person may be used.

  In the first embodiment described above, as shown in FIG. 11 and the like, the control unit 72 sets a region wider than the region of the subject (person) as the subject region, but the actual region of the subject (for example, An area formed by the outline of a person) may be the subject area. Alternatively, the subject detection unit 31 may detect a human face using a known face detection function, and the control unit 72 may use the face area detected by the subject detection unit 31 as a subject area. In the first embodiment described above, the control unit 72 adjusts the amount of illumination light of the light emitting unit 65 according to the distance from the digital camera system 1 to the subject. However, in addition to the amount of light, the control unit 72 emits illumination light. You may adjust time (light emission period).

  In the first embodiment described above, the control unit 72 executes the acquisition of luminance information and distance information (step S10) and the dimming calculation for each region (step S11) based on the full pressing operation of the release switch. However, it may be executed based on a half-press operation of the release switch.

  As described above, in the first embodiment, the imaging unit 20 having the imaging element 100, the light emitting unit 65 that emits light to the subject including the first subject O1 and the second subject O2, and the first subject The subject detection unit 31 that detects O1 and the second subject O2, and the first subject O1 so that the exposure to the first subject O1 and the exposure to the second subject O2 are appropriate exposure according to the amount of light from the light emitting unit 65. And a control unit 72 that changes the imaging conditions for imaging of the second subject O2. According to such a configuration, it is possible to capture images with appropriate brightness with respect to the plurality of subjects O1 and O2.

  In the first embodiment, the light emitting unit 65 is configured by a first light source whose light emission amount changes with time, and the control unit 72 changes the gain as an imaging condition. According to such a configuration, the brightness of the plurality of subject images can be adjusted to an appropriate brightness even when the exposure time is short. In the first embodiment, the light emitting unit 65 is configured by a second light source whose light emission amount does not change with time, and the control unit 72 changes at least one of gain and exposure time as an imaging condition. According to such a configuration, it is possible to adjust the brightness of a plurality of subject images to an appropriate brightness according to the subject, shooting conditions, and the like.

  In the first embodiment, a distance detection unit 71 that detects the distance from the image sensor 100 to the subject is provided, and the control unit 72 exposes the first subject O1 based on the distance detected by the distance detection unit 71. And the exposure to the second subject O2. According to such a configuration, it is possible to capture images with appropriate brightness with respect to a plurality of subjects O1 and O2 having different distances from the imaging device (digital camera system 1).

  In the first embodiment, the distance detection unit 71 includes a focus detection unit that detects a focus on the subject. According to such a configuration, the distance to the subject can be detected using the focus detection unit (AF function) provided in the imaging apparatus (digital camera system 1), and the distance to the subject can be detected. Devices such as special sensors are not required.

  In the first embodiment, the control unit 72 adjusts the exposure amount (exposure amount) for the first subject O1 and the exposure amount (exposure amount) for the second subject O2 in accordance with the determined light emission amount of the illumination light from the light emitting unit 65. The image capturing condition of the first subject O1 and the image capturing condition of the second subject O2 are set independently so that the appropriate exposure is obtained. According to such a configuration, the control unit 72 adjusts the exposure amount of the plurality of subjects O1, O2 using the light emission amount of the light emitting unit 65 and the imaging conditions (gain, shutter speed) as parameters, and thus the plurality of subjects O1, O2 The brightness of the image can be easily adjusted.

  In the first embodiment, the control unit 72 corrects the white balance for the first subject image and the second subject image captured by the imaging unit 20 in accordance with each imaging condition. According to such a configuration, it is possible to solve the problem that the difference in color between the first subject image and the second subject image due to the difference between the imaging conditions becomes large.

  In the first embodiment described above, the digital camera system 1 has been described as an example of the imaging device. However, the digital camera system 1 is not limited to this. For example, the imaging device is configured by a device such as a smartphone, a mobile phone, or a personal computer having an imaging function. May be. Further, the image processing unit 30 and the system control unit 70 illustrated in FIG. 7 may be configured integrally. In this case, the system control unit having one body side CPU performs the processing based on the control program, thereby taking on the function of the image processing unit 30 and the function of the system control unit 70.

Second Embodiment
In the first embodiment described above, the control unit 72 provided in the system control unit 70 sets (changes) the imaging conditions so that the brightness of the images of a plurality of subjects is appropriate. On the other hand, in the second embodiment, the imaging unit 20 (specifically, the drive unit 21) shown in FIG. 7 has the imaging condition setting function performed by the control unit 72 of the system control unit 70. (In other words, the drive unit 21 has the function of the control unit 72).
In the first embodiment described above, the focus detection unit 71 detects the distance to each subject. In the second embodiment, the distance to detect the distance to each subject separately from the focus detection unit 71. Has a sensor

FIG. 14 is a block diagram showing a specific configuration of the main part according to the second embodiment. The signal processing chip 111 bears the function of the drive unit 21 shown in FIG. In FIG. 14, the same functions as those in the first embodiment (FIG. 7) are denoted by the same reference numerals as those in FIG. 7, and the description in the second embodiment is omitted. As described above, the function of the control unit 72 of the system control unit 70 (imaging condition setting function) is different from the first embodiment in that the imaging unit 20 has the function.
An arithmetic circuit (control unit) 416 provided in the signal processing chip 111 changes the imaging conditions so that the brightness of the images of the plurality of subjects is appropriate.

  The signal processing chip 111 includes a sensor control unit 441, a block control unit 442, a synchronization control unit 443, and a signal control unit 444 as shared control functions. The signal processing chip 111 includes a sensor control unit 441, a block control unit 442, a synchronization control unit 443, and a chip control unit 420 that performs overall control of the signal control unit 444. The chip control unit 420 converts the instruction received from the system control unit 70 and the imaging condition received from the arithmetic circuit 416 into control signals that can be executed by the control units 441 to 444 and delivers them to the respective control units.

  The sensor control unit 441 is configured to send control pulses (reset pulse, transfer pulse, selection pulse) related to charge accumulation and charge readout of each pixel to the imaging chip 113 based on a control signal from the chip control unit 420. I do. Specifically, the sensor control unit 441 controls the start and end of charge accumulation by sending a reset pulse and a transfer pulse to the target pixel. In addition, the sensor control unit 441 outputs a pixel signal to the output wiring 309 by sending a selection pulse to the readout pixel of the pixel signal.

  Based on the control signal from the chip control unit 420, the block control unit 442 performs control to send a specific pulse for specifying the unit group 131 to be driven and controlled to the imaging chip 113. As described above, the pixel region 113 </ b> A of the image sensor 100 is divided into a plurality of blocks 200. The plurality of blocks 200 include at least one unit group 131 per block. Pixels included in the same block 200 start charge accumulation at the same timing and end charge accumulation at the same timing. Therefore, the block control unit 442 blocks one or a plurality of unit groups 131 by sending a specific pulse to the target unit group 131 based on a control signal from the chip control unit 420. The transfer pulse and the reset pulse received by each pixel via the TX wiring 307 and the reset wiring 306 are the logical product of each pulse sent by the sensor control unit 441 and a specific pulse sent by the block control unit 442. As described above, the block control unit 442 controls each region as the independent block 200, thereby realizing charge accumulation control for each region.

  The synchronization control unit 443 performs control to send a synchronization signal to the imaging chip 113 based on the control signal from the chip control unit 420. Each pulse (reset pulse, transfer pulse, selection pulse) becomes active in the imaging chip 113 in synchronization with the synchronization signal. For example, the synchronization control unit 443 adjusts the synchronization signal, thereby realizing random control, thinning control, and the like in which only specific pixels of pixels belonging to the same unit group 131 are subject to drive control.

  The signal control unit 444 controls the gain (gain factor, amplification factor) of the amplifier 412 based on the control signal from the chip control unit 420. Further, the signal control unit 444 performs timing control on the A / D converter 413b based on the control signal from the chip control unit 420. The pixel signal output via the output wiring 309 is input to the A / D converter 413b via the amplifier 412 and the CDS circuit 413a. The A / D converter 413b converts the input pixel signal into a digital signal under the control of the signal control unit 444. The pixel signal converted into the digital signal is delivered to the demultiplexer 414. Then, the pixel signal is stored as a pixel value of digital data in the pixel memory 415 corresponding to each pixel by the demultiplexer 414.

  The signal processing chip 111 has a timing memory 430. Based on an instruction from the system control unit 70, the chip control unit 420 includes block classification information on which unit group 131 is combined to form the block 200, and how many charges each formed block 200 has. The number-of-accumulation information about whether to repeat accumulation (that is, charge accumulation timing) is stored in the timing memory 430. The timing memory 430 is configured by a flash RAM, for example. The chip controller 420 performs charge accumulation control in units of blocks by referring to the block classification information and the accumulation count information stored in the timing memory 430.

  The arithmetic circuit (control unit) 416 is connected to a distance sensor 90 that detects the distance to the subject. The arithmetic circuit 416 is connected to the light emitting unit 65. The arithmetic circuit 416 determines whether or not the release switch has been fully pressed based on an instruction signal received from the system control unit 70 via the chip control unit 420. In addition, the arithmetic circuit 416, based on an instruction signal received from the system control unit 70 via the chip control unit 420, blocks 200 constituting a plurality of subject areas and imaging conditions (gain, charge accumulation of the plurality of subject areas). Time (shutter speed)). The arithmetic circuit 416 acquires distance information from the distance sensor 90 when it is determined that the release switch is fully pressed. Then, the arithmetic circuit 416 recognizes distances to a plurality of subjects based on distance information from the distance sensor 90.

  The arithmetic circuit 416 reads the image data of each pixel (RAW data before image processing by the image processing unit 30) from the pixel memory 415 when determining that the release switch is fully pressed. Then, the arithmetic circuit 416 generates luminance distribution data indicating the luminance distribution before the light emitting unit 65 emits light based on the read image data. The arithmetic circuit 416 performs photometry using the luminance distribution data. In addition, the arithmetic circuit 416 determines imaging conditions such as a charge accumulation time (shutter speed) and gain, and an aperture value based on the photometric result. At this time, the arithmetic circuit 416 can determine an imaging condition that provides appropriate exposure for each block in the pixel region 113 </ b> A of the imaging device 100.

  In addition, when the illumination circuit 65 emits illumination light, the arithmetic circuit 416 determines the amount of light emitted by the light emitting unit 65 in addition to the imaging conditions and the aperture value that provide proper exposure. Specifically, the arithmetic circuit 416 determines an imaging condition and an aperture value that provide appropriate exposure as described above. The arithmetic circuit 416 also determines the amount of light to be emitted by the light emitting unit 65 based on the imaging conditions (in this case, gain) and the aperture value and the distance to the subject so as to achieve proper exposure. Note that the arithmetic circuit 416 determines whether the light emitting unit 65 emits illumination light or not from the system control unit 70 (a signal indicating that the user has performed an operation of causing the light emitting unit 65 to emit light) or the light emitting unit. It is possible to make a determination based on a signal from 65 (a signal indicating that the light emitting unit 65 automatically emits light).

  Further, the arithmetic circuit 416 is a case where the light emitting unit 65 emits illumination light, and when there are a plurality of subjects, at least one of the plurality of subjects may be too bright or too dark. The imaging condition of the subject area (see FIG. 11) is adjusted (changed) so that there is no subject. For example, the arithmetic circuit 416 determines an imaging condition and an aperture value that provide appropriate exposure as described above, and a light emission amount of illumination light that is emitted from the light emitting unit 65. Thereafter, the arithmetic circuit 416 makes the exposure amount for the plurality of subjects uniform (identical) or substantially uniform (substantially the same) in accordance with the amount of light emitted from the light emitting unit 65 based on the distance for each of the plurality of subjects. The imaging conditions in the pixels in the subject area for each of a plurality of subjects are adjusted.

  When adjusting the gain, the arithmetic circuit 416 outputs a control signal instructing the gain of the pixel signal of each subject area to the signal control unit 444 via the chip control unit 420. Further, when adjusting the charge accumulation time, the arithmetic circuit 416 outputs a control signal indicating the charge accumulation time of each subject region to the sensor control unit 441 and the block control unit 442 via the chip control unit 420. In addition, the arithmetic circuit 416 outputs an instruction signal for instructing the light emitting unit 65 to determine the amount of light to the system control unit 70 via the chip control unit 420. In addition, the arithmetic circuit 416 transmits control information indicating the aperture value to the system control unit 70 via the chip control unit 420.

  As the distance sensor 90, various types of sensors can be used. For example, the distance sensor 90 may be a sensor that measures the distance to the subject by irradiating the subject with light such as a laser and receiving light reflected from the subject. The distance sensor 90 is an image sensor different from the image sensor 100, and may measure the distance to the subject by receiving light from the subject.

  Next, the photographing operation of the digital camera system 1 according to the second embodiment will be described. FIG. 15 is a flowchart for explaining setting processing executed by the arithmetic circuit 416 of the second embodiment. In the processing shown in FIG. 15, the arithmetic circuit 416 acquires distance information from the distance sensor 90 when it is determined that the release switch is fully pressed based on an instruction signal from the system control unit 70. Luminance information (luminance distribution data) is acquired based on the image signal (step S21). Then, the arithmetic circuit 416 recognizes distances to a plurality of subjects based on distance information from the distance sensor 90. Further, the arithmetic circuit 416 performs dimming calculation for each region (for example, the subject regions 511 and 512 shown in FIG. 11) based on the luminance information (step S22).

  Since the operation in step S22 is the same as the operation in step S11 (FIG. 12), the description thereof is omitted here.

Next, the arithmetic circuit 416 sets the guide number determined in step S22, the imaging conditions (gain, shutter speed, etc.) for each region (subject regions 511, 512), and the aperture value (step S23).
Then, the arithmetic circuit 416 outputs an instruction signal for instructing the light amount represented by the guide number to the system control unit 70. The system control unit 70 outputs an instruction signal to the light emitting unit 65 when performing main light emission, thereby causing the light emitting unit 65 to start emitting illumination light, and the control unit 72 executes still image imaging processing. . At this time, the system control unit 70 executes the imaging process based on the imaging condition, the aperture value, and the like determined by the arithmetic circuit 416. By performing such an imaging process, a still image is captured in which the image of the person O1 and the image of the person O2 have appropriate brightness.

As described above, in the second embodiment, in addition to the effects of the first embodiment described above, the function of the control unit 72 is provided in the imaging unit 20, and thus the image processing unit 30 and the system control unit 70 are provided. The processing load can be reduced.
In the second embodiment, the distance sensor provided separately from the image sensor is used as the means for obtaining the subject distance. However, the present invention is not limited to this, and the image sensor is used for phase difference detection as in the first embodiment. An image sensor in which pixels are embedded may be used, and the subject distance may be obtained based on the output of the phase difference detection pixels.

<Third Embodiment>
In the first embodiment described above, the control unit 72 calculates the distance to the subject based on the defocus amount from the focus detection unit 71, and adjusts the brightness of the images of the plurality of subjects based on the calculated distance. On the other hand, in the third embodiment, the control unit 72 causes the light emitting unit 65 to perform pre-light emission (also referred to as preliminary light emission, pre-light emission, or monitor light emission) before the main image pickup (image pickup in step S14). Based on the measurement result (reflected light amount) of the reflected light from the subject that has been irradiated, the main light emission amount (light emission amount during main imaging) is determined, and auxiliary light shooting is performed with the determined main light emission amount. This is a method for capturing images of a plurality of subjects with appropriate brightness. That is, the imaging condition for imaging a plurality of subjects with appropriate exposure is obtained without using distance information from the camera to the subject at the time of auxiliary light photographing.
The block diagram of the third embodiment is the same as that of the first embodiment (FIG. 7), and the description thereof is omitted here.
In the third embodiment, it is assumed that a xenon tube that emits flash illumination light is used as the light source of the light emitting unit 65.

  FIG. 16 is a flowchart for explaining a photographing operation executed by the system control unit 70 of the third embodiment. Note that the processing from steps S1 to S8 and the processing from steps S12 to S14 shown in FIG. 16 are the same as the processing described in FIG. 12 (first embodiment). Therefore, the overlapping description is omitted.

If the system control unit 70 determines in step S8 that the release switch has been fully pressed, the process proceeds to step S29.
In step S29, the control unit 72 performs a photometric operation (Bv calculation) of the object scene based on the image signal output from the image sensor 100, and determines the imaging conditions (Tv1, Av1, Sv1) during the main imaging. To do.
Here, in the third embodiment, among the subject area 511 including the person O1 and the subject area 512 including the person O2 shown in FIG. This is described as an area serving as a reference for (ie, an area serving as a reference for setting exposure conditions during actual imaging).

In step S29, the control unit 72 acquires the luminance value Bv1 of the subject region 511 based on the image signal corresponding to the subject region 511 including the person O1. Based on the brightness value Bv1, the control unit 72 calculates an imaging condition such as a shutter speed (Tv1) and a gain (Sv1) at which the person O1 is properly exposed, and an aperture value Av1, so-called APEX calculation (Ev = Tv + Av, Ev = Sv + Bv).
In step S30, the controller 72 starts pre-emission before the main emission. FIG. 17 is a graph showing the relationship between the pre-light emission and main light emission timings and the light quantity. Note that FIG. 17 shows a case where the light emission control unit 65B causes the xenon tube as the light source 65A to emit light. As shown in FIG. 17, the pre-emission light quantity L1 is a light quantity sufficiently smaller than the main emission light quantity L2 (a numerical value with a small guide number, for example, a light quantity such as guide number 2). The pre-emission amount is determined in advance, and is stored in advance in a control memory in the light emitting unit 65 or a control memory in the system control unit 70. Further, in the pre-light emission operation, the light emission is started and completed at the timing t1 before the light emission start timing t2 of the main light emission. Note that the pre-light emission is not limited to one light emission and may be a plurality of times of light emission such as twice or three times.

  In step S31, the control unit 72 performs imaging with, for example, predetermined imaging conditions at the time of pre-emission (aperture value Avp for pre-emission, a shutter speed Tvp for pre-emission, and a gain Svp for pre-emission). Such an imaging process is called pre-flash imaging process. As the imaging condition at the time of pre-emission, for example, an imaging condition in which the gain is set higher than normal is assumed. The control unit 72 outputs an instruction signal for instructing imaging conditions at the time of pre-emission to the driving unit 21. Based on the instruction signal from the control unit 72, the drive unit 21 drives and controls the image sensor 100 during pre-emission. The image sensor 100 generates RAW data including pixel signals of each pixel when pre-emission is performed, and outputs the generated RAW data to the image processing unit 30. The image processing unit 30 generates reflected light amount distribution data (distributed light amount distribution data from the subject that has received pre-emission) from the RAW data.

  Further, in step S31, at the timing after the pre-emission, the control unit 72 performs the imaging when the pre-emission is not performed, at least in the imaging conditions (Av2, Tv2, Sv2) at the time of the pre-emission. Perform once. With this imaging, it is possible to perform imaging with natural light (without illumination light from the light emitting unit 65) under the same imaging conditions as the pre-light emission conditions. Then, similarly to the case of imaging at the time of pre-emission, light amount distribution data (distribution data of light amount from a subject that has received natural light) is generated. The imaging without pre-emission (natural light imaging) may be performed before pre-emission if the imaging conditions (Av2, Tv2, Sv2) at the time of pre-emission are set. good.

Further, in step S31, the control unit 72 influences only the pre-light emission based on the image pickup signal (the image pickup signal without pre-light emission and the image pickup signal with pre-light emission) obtained by the image pickup twice from the image processing unit 30. Reflected light amount distribution data (hereinafter referred to as differential light amount distribution data or reflected light amount data) is acquired. Specifically, a difference for each divided image area (each pixel group or each pixel) is calculated between the luminance distribution data obtained from both images.
In step S32, the control unit 72 obtains the reflected light amount distribution data R at the time of pre-emission, the imaging conditions at the time of pre-emission (Av2, Sv2), and the imaging conditions at the time of main imaging (Av1, Sv2) obtained at step S29. Based on Sv1) and using the following formulas (2) and (3), dimming calculation is performed for each region (for example, the subject regions 511 and 512 shown in FIG. 11), and the subject regions 511 and 512 are appropriately set. A main light emission amount V for exposure and an imaging condition (Sv) of each region are obtained.

      Q = -log2 (R) + Sv2-Av2 + Av1-Sv1 + K (2)

V = GNop × (√2) ^Q (3)

In the above formulas (2) and (3),
“R” is the amount of reflected light from the desired region (in this embodiment, the exposure reference region 511) that has received pre-emission;
“Log2 (R)” is the logarithm of R with base 2;
“GNop” is a pre-emission amount (fixed value: for example, guide number 2),
“Q” is the number of steps indicating how much light should be emitted with respect to the pre-emission light emission amount GNp, and “V” is the light emission amount (guide number) for making a desired region have proper exposure. ,
“(√2) ^Q ” is the Q power of route 2,
“K” is a constant,
Indicates.

  Referring to FIG. 11B, since the exposure reference area is the subject area 511 including the person O1, the reflected light amount R1 of the subject area 511 is first obtained from the reflected light quantity distribution data. Then, the amount of reflected light R1 and the imaging conditions (Tv1, Sv1, Av1) determined in step S29 are substituted into the above equation (2) for calculation. As a result of this calculation, when the main light emission is illuminated with an amount of light (Q steps) larger than the light emission guide number GNop for the pre-light emission, the subject area 511 is appropriate at the time of main imaging (imaging conditions = Tv1, Sv1, Av1) Whether exposure can be obtained is required.

Next, the main light emission amount V is obtained by substituting Q calculated above into the above equation (3).
Next, when auxiliary light imaging is performed with the main light emission amount V, “Gain Sv3” which is an imaging condition for properly exposing other areas (subject area 512 including the person O2) is expressed by the above equation (2). Find using.
First, the main flash amount V itself is common regardless of the subject area.
The relational expression “main light emission amount V for properly exposing the region 511” = “main light emission amount for properly exposing the region 512” is established. That is, the relational expression “Q calculated for the region 511” = “Q calculated for the region 512” is satisfied.
Therefore, if the reflected light amount R2 of the subject region 512 obtained from the reflected light amount distribution data,
"-Log2 (R1) + Sv2-Av2 + Av1-Sv1 + K
= -Log2 (R2) + Sv2-Av2 + Av1-Sv3 + K "
And expand this,
Sv3 = −log2 (R1 / R2) + Sv1,
It becomes.
As described above, the main light emission amount V, the imaging condition Sv1 (gain of the subject area 511) and the imaging condition Sv3 (gain of the subject area 512) that provide proper exposure when the main light emission amount V is obtained.

  Thereafter, similarly to the first embodiment described above, the control unit 72 sets a guide number, an imaging condition, and the like (step S12). Further, the control unit 72 starts main light emission (step S13). In addition, the control unit 72 executes an imaging process (step S14).

  As described above, in the third embodiment, the light emitting unit 65 performs preliminary light emission before the main light emission, and the control unit 72 determines the first subject based on the amount of reflected light from the subject based on the preliminary light emission. A main light emission amount and an imaging condition for each subject for obtaining appropriate exposure for each of O1 and second subject O2 are determined. According to such a configuration, in addition to the effects of the first embodiment described above, auxiliary light imaging can be performed with appropriate brightness for a plurality of subjects without having a means for obtaining the subject distance.

In the third embodiment, since a xenon tube (flash illumination light) is used as the light source of the light emitting unit 65, an imaging sensitivity (gain Sv) is set as an imaging condition adjusted for each subject area in order to obtain an appropriate exposure for each subject. ) Was explained. However, when a light source that emits continuous light, such as an LED, is used as the light source, the image capturing condition to be adjusted may be the shutter speed instead of the gain, or a combination of both (Tv and Sv). It is also good. In addition, when obtaining an appropriate imaging condition based on the result of pre-light emission of the LED and receiving light, the guide number QL (for example, around guide number 10) of a certain size that is also used in the main light emission is instantaneous ( For a short time (for example, 1 ms to several ms), pre-emit the LED to obtain the reflected light amount at that time, and when the LED emission is continued with the guide number QL, the emission duration required to obtain proper exposure, In other words, the accumulation time (shutter speed Tv) may be obtained for each region.
In the third embodiment, the reflected light amount data by the pre-emission is obtained. However, the reflectance data of the subject (reflectance distribution data of the object field) is obtained based on the pre-emission amount and the reflected light amount, and this is obtained. The main light emission amount and the imaging condition may be obtained based on the above.

<Fourth embodiment>
In 4th Embodiment, it is set as the structure which isolate | separated the camera body 2 of the digital camera system 1 in above-described 1st Embodiment into the imaging device 2A and the electronic device 2B.

  FIG. 18 is a block diagram illustrating configurations of the imaging device 2A and the electronic device 2B according to the fourth embodiment. In the configuration shown in FIG. 18, the imaging device 2A is a device that images a subject. The imaging apparatus 2A includes a lens unit 10, an imaging unit 20, an image processing unit 30, a work memory 40, an operation unit 55, a recording unit 60, a first system control unit (control unit) 75, and a light emitting unit 65. In the imaging apparatus 2A, the configurations of the lens unit 10, the imaging unit 20, the image processing unit 30, the work memory 40, the operation unit 55, the recording unit 60, and the light emitting unit 65 are the same as those illustrated in FIG. is there. Accordingly, the same functions as those shown in FIG. 7 are denoted by the same reference numerals, and redundant description is omitted.

  The electronic device 2B is a device that displays images (still images, moving images, live view images). The electronic apparatus 2B includes a display unit 50 and a second system control unit (control unit) 76. The configuration of the display unit 50 in the electronic device 2B is the same as the configuration illustrated in FIG. Accordingly, the same components are denoted by the same reference numerals, and redundant description is omitted.

  The first system control unit 75 includes a first communication unit 75A. Further, the second system control unit 76 includes a second communication unit 76A. The first communication unit 75A and the second communication unit 76A transmit and receive signals to each other in a wired or wireless manner. In such a configuration, the first system control unit 75 receives the second image data (image data image-processed by the image processing unit 30 and image data recorded in the recording unit 60) via the first communication unit 75A. It transmits to the communication part 76A. The second system control unit 76 causes the display unit 50 to display the image data received by the second communication unit 76A. Further, the second system control unit 76 causes the display unit 50 to display a preset menu image.

  Further, the second system control unit 76 performs control to change the imaging condition (including the accumulation condition). In addition, the second system control unit 76 performs control to set the area of the pixel area 113A. In addition, the first system control unit 75 executes imaging control according to the operation of the operation unit 55 by the user.

  The configuration (focus detection unit 71 and control unit 72) illustrated in FIG. 7 may be provided in either the first system control unit 75 or the second system control unit 76. 7 may be provided in the first system control unit 75 or the second system control unit 76, and a part of the configuration shown in FIG. 7 is provided in the first system control unit 75. 7 may be provided in the second system control unit 76 other than a part of the configuration shown in FIG.

  Note that the imaging device 2A includes, for example, a digital camera, a smartphone, a mobile phone, and a personal computer that have an imaging function and a communication function, and the electronic device 2B includes, for example, a smartphone, a mobile phone, and a portable personal computer that have a communication function. Consists of a portable terminal such as a computer.

  The first system control unit 75 shown in FIG. 18 is realized by the body side CPU executing processing based on the control program. Further, the second system control unit 76 shown in FIG. 18 is realized by the body side CPU executing processing based on the control program.

  As described above, in the fourth embodiment, in addition to the effects described in the first to third embodiments, an image is captured by the imaging device 2A using a mobile terminal (electronic device 2B) such as a smartphone. Imaging can be performed after confirming a plurality of live view images.

  In the configuration shown in FIG. 18, the image processing unit 30 and the first system control unit 75 may be configured integrally. In this case, a system control unit having one or more CPUs performs the processing based on the control program, thereby taking on the function of the image processing unit 30 and the function of the first system control unit 75.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various modifications or improvements can be added to the above-described embodiment without departing from the spirit of the present invention. In addition, one or more of the requirements described in the above embodiments may be omitted. Such modifications, improvements, and omitted forms are also included in the technical scope of the present invention. In addition, the configurations of the above-described embodiments and modifications can be applied in appropriate combinations.

In each of the embodiments described above, the arrangement of the color filters 102 is a Bayer arrangement, but an arrangement other than this arrangement may be used.
Further, the number of pixels forming the unit group 131 only needs to include at least one pixel.
In addition, the block only needs to include at least one pixel. Therefore, it is possible to execute imaging under different imaging conditions for each pixel.

  In each embodiment described above, part or all of the configuration of the drive unit 21 may be mounted on the imaging chip 113, or part or all of the configuration may be mounted on the signal processing chip 111. Further, a part of the configuration of the image processing unit 30 may be mounted on the imaging chip 113 or the signal processing chip 111. Further, a part of the configuration of the system control unit 70 may be mounted on the imaging chip 113 or the signal processing chip 111.

  Further, in each of the above-described embodiments, imaging conditions that can be set by the system control unit 70 are not limited to gain, charge accumulation time (exposure time, shutter speed), and frame rate, but may be other control parameters. Although only the case where the imaging condition is automatically set has been described, it may be set according to the operation of the operation unit 55 by the user.

  In each of the above-described embodiments, the case where the size of the block area is set in advance has been described. However, the user may set the size of the block area.

  Moreover, it is possible to combine the structure of each embodiment mentioned above suitably. For example, the control unit 72 of the system control unit 70 may acquire distance information for each subject using the distance sensor 90 (see FIG. 14). Further, the arithmetic circuit 416 of the signal processing chip 111 may determine the imaging condition, the light amount of the light emitting unit 65, and the like based on the reflectance.

  In the first embodiment described above, the control unit 72 calculates the guide number, the imaging condition, and the like using the above formula (1). However, the calculation is not limited to such a calculation. For example, the control unit 72 calculates a difference between the distance from the digital camera system 1 to the person O1 and the distance from the digital camera system 1 to the person O2, and based on the difference, the gains of the plurality of subject areas 511 and 512 are calculated. The shutter speed may be calculated.

  In each of the above-described embodiments, the case of capturing a still image has been described, but the present invention can also be applied to the case of capturing a moving image. However, since a moving image is captured for a longer time than when a still image is captured, the light emitting unit 65 includes an LED (second light source). In such a case, the brightness of the images of the persons O1 and O2 can be adjusted by changing the imaging sensitivity (gain). It is also conceivable to adjust the brightness of the images of the persons O1 and O2 by changing the frame rate.

  When a plurality of light sources with high directivity are used as the light source of the light emitting unit 65 and the plurality of light sources are distributed and used for each subject, the light quantity of each light source is changed for each of the plurality of subjects. May be.

The digital camera system 1 in each of the above embodiments may be configured with devices such as a digital camera, a smartphone, a mobile phone, and a personal computer having an imaging function, for example.
In the above-described embodiment, the digital camera system (imaging system) 1 is configured by the camera body 2 and the lens unit (interchangeable lens) 10 that can be attached to and detached from the camera body. An integrated digital camera in which the body 2 and the lens unit 10 are integrally molded (not detachable) may be used.
In the above embodiment, the camera body 2 (imaging device 2A) has been described as including the light emitting unit 65. However, the present invention is not limited thereto, and the light emitting unit 65 can be attached to and detached from the camera body 2 (imaging device 2A). A system configuration (an imaging system including a so-called external illumination device) may be used.

  In each of the above embodiments, when determining the aperture value in auxiliary light imaging, the aperture value may be determined in consideration of the depth of field by the aperture. That is, in order to obtain an image focused on both the closest subject and the distant subject, the aperture 14 in the lens unit 10 may be set in the direction of narrowing down using the depth of field. . In this case, the amount of light at the time of imaging of the aperture 14 decreases as the aperture amount increases (the aperture value increases). Depending on the balance with the gain (imaging sensitivity) of the image sensor 100, depending on the imaging scene, it may not be possible to increase the depth of field by reducing the aperture 14 extremely (to a large aperture value). For example, this is the case of a dark shooting scene or backlight scene with shooting illumination light (auxiliary light) in order to obtain an appropriate exposure (if the aperture 14 is reduced, the amount of light emission must be increased by that amount. Because there is also an upper limit on the amount of light that can reach. In such a case, the amount of movement of the focusing lens 11c to the in-focus position takes into account not only the defocus amount for the closest subject but also the defocus amount for the far subject (for example, a weighted average calculation method). You may make it decide using (). In this way, the in-focus position of the focusing lens 11c can be set at a position (intermediate position) between the in-focus position A for the closest subject and the in-focus position B for the other subject (within the range). Therefore, even when it is necessary to set an aperture value at which the depth of field becomes shallow, it is possible to increase the possibility of obtaining an image focused on both subjects (the closest subject and the far subject). . Note that when the in-focus position is determined by weighted average calculation, since the depth of field is more severe than the infinite side, the weight on the defocus amount of the closest subject is set to the defocus amount of the far subject. It is desirable to make the determination larger than the weight for (this makes it possible to control the focal point position closer to the focal point position with respect to the closest subject).

  Further, when determining the shutter speed in the subject area at the time of auxiliary light imaging, the shutter speed may be determined in consideration of the camera shake limit speed or the flash synchronization speed. In the case of imaging in which the shutter speed is limited in this way, a gain change is applied as a change in imaging conditions for each subject area.

  DESCRIPTION OF SYMBOLS 1 ... Digital camera system (imaging system), 2A ... Imaging device, 2B ... Electronic device, 11 ... Imaging optical system, 20 ... Imaging part, 30 ... Image processing part, 50 ... Display part, 51 ... Touch panel, 55 ... Operation part , 65 ... Light emitting part (illumination part), 70 ... System control part, 75 ... First system control part (control part), 76 ... Second system system control part (control part), 71 ... Focus detection part (distance detection part) , 72... Control unit, 90... Distance sensor (distance detection unit), 100... Image sensor, 416.

Claims (12)

An imaging device for imaging a first subject and a second subject irradiated with illumination light within an imaging field,
A first imaging region having a plurality of first pixels having a first photoelectric conversion unit that converts light from the first subject into electric charge and a first transfer unit that transfers electric charge of the first photoelectric conversion unit; A second imaging region having a plurality of second pixels having a second photoelectric conversion unit that converts light from two subjects into electric charge and a second transfer unit that transfers electric charge of the second photoelectric conversion unit; A first wiring connected to one pixel and supplied with a signal for controlling a transfer operation of the first transfer unit; and a signal connected to a plurality of the second pixels and controlling a transfer operation of the second transfer unit. The supplied second wiring different from the first wiring, the first output line for outputting a signal generated by the charges converted by the photoelectric conversion of the plurality of first pixels, and the photoelectric of the plurality of second pixels. A second output line for outputting a signal generated by the electric charge converted by the conversion; An imaging element having,
A first acquisition unit that acquires position information regarding the positions of the first subject and the second subject within the imaging field;
When imaging the first subject and the second subject irradiated with the illumination light, the first subject and the second subject can each obtain a predetermined amount of exposure by the illumination light irradiation. An imaging apparatus comprising: a control unit that independently controls an imaging condition of the first imaging area and an imaging condition of the second imaging area based on position information. The imaging apparatus according to claim 1 ,
The first acquisition unit acquires an existence position of the first subject and the second subject on an imaging surface of the imaging element . The imaging apparatus according to claim 2 ,
A second obtaining unit that obtains light amount information related to a light emission amount of the illumination light;
The first acquisition unit further acquires distance information from the imaging device of the first subject and the second subject within the imaging field of view,
The control unit controls an imaging condition of the first imaging area and an imaging condition of the second imaging area based on the light amount information, the distance information, and the position information. The imaging apparatus according to claim 2,
Before irradiating the illumination light of the first object and the second object are irradiated to obtain the exposure of the predetermined amount, the first object and the second object with a small amount than the amount of the illumination light A third acquisition unit that performs pre-irradiation and acquires luminance distribution information related to the influence of the pre-irradiation on the luminance of the first subject and the second subject ;
The control unit controls an imaging condition of the first imaging area and an imaging condition of the second imaging area based on the luminance distribution information and the position information. The imaging apparatus according to any one of claims 1 to 4,
A light-emitting unit composed of a first light source whose light emission amount changes with time,
The said control part changes imaging sensitivity as said imaging condition, The imaging device characterized by the above-mentioned. The imaging apparatus according to any one of claims 1 to 4,
Including a light emitting unit composed of a second light source capable of maintaining a predetermined light emission amount for a predetermined time;
Wherein the control unit, an imaging apparatus characterized by changing at least one of the imaging sensitivity and the exposure time as the imaging condition. The imaging apparatus according to claim 3,
Said distance information, an imaging apparatus characterized by being detected by the focus detection unit for detecting a focus for the first object and the second object. The imaging device according to claim 5 or 6 , wherein
The control unit is so exposed and may have an appropriate exposure to the exposure and the second object to the first object in accordance with the amount of light from the light-emitting amount of the light emitting portion, and the first object and the imaging device and sets the imaging conditions of the imaging condition and the second imaging area of the first imaging region of the second object. The imaging apparatus according to any one of claims 1 to 8,
The control unit corrects white balance for the first subject image and the second subject image captured by the image sensor in accordance with the change of the imaging condition of the first imaging region and the imaging condition of the second imaging region. An imaging apparatus characterized by: An imaging apparatus according to any one of claims 1 to 9,
An imaging unit including the imaging element;
The image pickup apparatus, wherein the control unit is provided in the image pickup unit. A method for controlling an imaging apparatus having an imaging element for imaging light from a first subject and a second subject irradiated with illumination light within an imaging field,
The imaging device includes a plurality of first pixels each including a first photoelectric conversion unit that converts light from the first subject into electric charge and a first transfer unit that transfers electric charge of the first photoelectric conversion unit. A second imaging region having a plurality of second pixels each having a region, a second photoelectric conversion unit that converts light from the second subject into electric charge, and a second transfer unit that transfers electric charge of the second photoelectric conversion unit; A first wiring connected to a plurality of the first pixels and supplied with a signal for controlling a transfer operation of the first transfer unit; and a transfer operation of the second transfer unit connected to the plurality of second pixels. A second wiring different from the first wiring, a first output line for outputting a signal generated by charges converted by photoelectric conversion of the plurality of first pixels, and a plurality of the first wiring A signal generated by the charge converted by the photoelectric conversion of the second pixel is output. It has a second output line, and
Obtaining position information relating to the positions of the first subject and the second subject within the imaging field;
When imaging the first subject and the second subject irradiated with the illumination light, the first subject and the second subject can each obtain a predetermined amount of exposure by the illumination light irradiation. A method for controlling an imaging apparatus, comprising: independently controlling an imaging condition of the first imaging area and an imaging condition of the second imaging area based on position information. A control program used in an imaging apparatus having an imaging element that images light from a first subject and a second subject irradiated with illumination light within an imaging field,
The imaging device includes a plurality of first pixels each including a first photoelectric conversion unit that converts light from the first subject into electric charge and a first transfer unit that transfers electric charge of the first photoelectric conversion unit. A second imaging region having a plurality of second pixels each having a region, a second photoelectric conversion unit that converts light from the second subject into electric charge, and a second transfer unit that transfers electric charge of the second photoelectric conversion unit; A first wiring connected to a plurality of the first pixels and supplied with a signal for controlling a transfer operation of the first transfer unit; and a transfer operation of the second transfer unit connected to the plurality of second pixels. A second wiring different from the first wiring, a first output line for outputting a signal generated by charges converted by photoelectric conversion of the plurality of first pixels, and a plurality of the first wiring A signal generated by the charge converted by the photoelectric conversion of the second pixel is output. It has a second output line, and
Processing for obtaining position information regarding the positions of the first subject and the second subject within the imaging field;
When imaging the first subject and the second subject irradiated with the illumination light, the first subject and the second subject can each obtain a predetermined amount of exposure by the illumination light irradiation. A control program that causes the imaging apparatus to execute processing for independently controlling the imaging conditions of the first imaging area and the imaging conditions of the second imaging area based on position information.