KR101757655B1 - Image pickup element, image pickup apparatus, method for controlling the same, and storage medium - Google Patents

Abstract

An imaging device according to the present invention is an imaging device including an optical system for imaging an optical image for forming an optical image of a subject and generating an image signal, the imaging device comprising: a pixel having a pixel portion including a plurality of pixels arranged in a matrix; First element means including first element means and reading means for reading the optical image from the pixel portion, the plurality of pixels being arranged to photoelectrically convert the optical image to generate an image signal , The reading means includes first reading means for reading the image signal from the first pixel group of the pixel portion, and second reading means for reading the image signal from the second pixel group of the pixel portion; Imaging condition determining means for obtaining information about the imaging condition of the optical image from the image signal output from the imaging device and determining the imaging condition using the acquired information; And image pickup evaluation means for detecting, from one of the image signals read by the first reading means and the second reading means, an image pickup evaluation value related to the optical image pickup based on a result of the determination by the image pickup condition determining means Value detecting means.

Description

TECHNICAL FIELD [0001] The present invention relates to an image pickup device, an image pickup device, a control method thereof, and a storage medium. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to an image pickup device having a laminated structure, an image pickup apparatus having the image pickup device, a control method thereof, and a storage medium. More specifically, the present invention relates to an imaging device capable of detecting an evaluation value relating to photometry, fielding, etc. according to an image signal.

There is a technique of performing image evaluation and image display using a signal picked up by an image pickup apparatus. In an apparatus disclosed in Japanese Patent Application Laid-Open No. 2009-89105, a live-view reading mode and an automatic exposure reading mode for focus detection are disclosed. The live view reading mode is for reading an image pickup signal for live view display and the auto exposure reading mode for focus detection is for reading an image pickup signal for use in focus detection signal and photometry information for automatic exposure from an image pickup element will be. These read modes are repeated cyclically for each frame.

However, in Japanese Patent Application Laid-Open No. 2009-89105, since an image signal (that is, charge) is read from an image pickup element on a pixel-by-pixel basis, not only time is required to transfer the charge but also the amount of data to be transferred increases, .

Furthermore, the image signal, which is the output of the image pickup device, is subjected to image signal processing by another device such as a control device. As a result, a large amount of data to be transmitted causes the processing load of the control device to increase.

In addition, in Japanese Patent Application Laid-Open No. 2009-89105, a focus signal detection pixel is provided in the pixel portion, which inevitably reduces the area allocated to the image signal pixel. Since the focus signal detection pixels are not used when obtaining an image pickup signal (image signal), the image quality is deteriorated.

Therefore, it is an object of the present invention to provide an image pickup device and an image pickup apparatus, a control method thereof, and a storage medium that reduce a data transfer time and a deterioration in image quality.

In order to achieve the above object, an image pickup device according to the present invention is an image pickup device including an optical system for picking up an optical image for forming an optical image of a subject and generating an image signal, comprising: a plurality of pixels arranged in a matrix And second reading means for reading the optical image from the pixel portion, wherein the plurality of pixels are arranged in a matrix form so as to form the optical image Wherein the reading means includes first reading means for reading the image signal from the first pixel group of the pixel portion, second reading means for reading the image signal from the second pixel group of the pixel portion, An imaging device including: Imaging condition determining means for obtaining information about the imaging condition of the optical image from the image signal output from the imaging device and determining the imaging condition using the acquired information; And image pickup evaluation means for detecting, from one of the image signals read by the first reading means and the second reading means, an image pickup evaluation value related to the optical image pickup based on a result of the determination by the image pickup condition determining means Value detecting means.

In another aspect of the present invention, a control method according to the present invention includes an optical system for forming an optical image of a subject and an imaging element for imaging the optical image to generate an image signal, wherein the imaging element has a matrix shape And a second element means including first element means having a pixel portion including a plurality of arranged pixels and reading means for reading the optical image from the pixel portion, Wherein the reading means comprises: first reading means for reading the image signal from the first pixel group of the pixel portion; and second reading means for reading the image signal from the second pixel group of the pixel portion And a second reading means for reading out the optical image from the image signal outputted from the image pickup element, Acquiring information on a condition, and determining the imaging condition using the acquired information; And detecting an imaging evaluation value related to the imaging of the optical image based on the determined imaging condition from one of the image signals read by the first reading means and the second reading means.

Further features of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings.

1 is a block diagram showing an example of the configuration of an image pickup apparatus according to the first embodiment of the present invention.
2A and 2B are explanatory diagrams showing the configuration of the imaging element shown in Fig.
3 is a diagram showing pixel selection in the column signal line on the first chip shown in Figs. 2A and 2B. Fig.
Fig. 4 is a timing chart for explaining the imaging timing in the AF evaluation mode in the camera shown in Fig. 1. Fig.
Fig. 5 is a flowchart for explaining control in the camera shown in Fig. 1. Fig.
6 is a block diagram showing the configuration of an example of an image pickup device used in a camera according to the second embodiment of the present invention.
Fig. 7 is a timing chart for explaining the imaging timing in the photometric evaluation mode in the second embodiment of the present invention. Fig.
8 is a block diagram showing the configuration of an example of an image pickup device used in a camera according to the third embodiment of the present invention.
9 is a timing chart for explaining the imaging timing in the standard deviation evaluation mode in the third embodiment of the present invention.
10 is an explanatory diagram showing the timing of an autofocus imaging operation for a live view in a conventional imaging apparatus.
11 is a block diagram showing a configuration of an image pickup apparatus according to a fourth embodiment of the present invention.
12A and 12B show the configuration of an image pickup device included in the image pickup apparatus according to the fourth embodiment of the present invention.
13 is an explanatory view showing a reading structure of a pixel portion of an imaging device used in an imaging device according to a fourth embodiment of the present invention.
14A and 14B show the imaging timing of the imaging apparatus according to the fourth embodiment of the present invention.
15 is a flowchart showing the operation in the AF mode of the imaging apparatus according to the fourth embodiment of the present invention.
16 shows a configuration of an image pickup apparatus according to the fifth embodiment of the present invention.
17 is a flowchart showing the operation in the AF mode of the imaging apparatus according to the fifth embodiment of the present invention.
18 is a judgment table showing a scene judgment in the image pickup apparatus according to the fifth embodiment of the present invention.
Fig. 19 shows a configuration of an image pickup apparatus according to the sixth embodiment of the present invention.

Hereinafter, various embodiments, features and aspects of the present invention will be described in detail with reference to the drawings. Hereinafter, an example of an image pickup apparatus according to embodiments of the present invention will be described with reference to the drawings.

First Embodiment

1 is a block diagram showing an example of the configuration of an image pickup apparatus according to the first embodiment of the present invention.

The image pickup apparatus shown in the drawing is applied to, for example, a digital still camera or a video camera having a moving image function.

The imaging apparatus 100 includes an optical lens barrel 101, an imaging device 102, a driving unit 103, a signal processing unit 104, a compression expansion unit 105, a control unit 106, a light emitting unit 107, 108, an image display unit 109, and an image recording unit 110.

The optical lens barrel 101 is provided with a lens unit (not shown in the figure, hereinafter simply referred to as a lens) and a mechanical optical portion 1011. The lens condenses (i.e., images) the light (optical image) from the object on the image pickup element 102.

Although not shown in the drawing, the mechanical optical portion 1011 has an AF mechanism, a zoom driving mechanism, a mechanical shutter mechanism, and an iris mechanism. The mechanical optical portion 1011 is driven by the driving portion 103 under the control of the control portion 106. [

The image pickup device 102 has a pixel portion 201 and an A / D converter (not shown), which will be described later. For example, the image pickup device 102 is a so-called XY read CMOS type image sensor. The imaging device 102 performs imaging operations such as exposure, signal reading, and reset by a driving unit 103 operated under the control of the control unit 106. [ Further, the image pickup device 102 outputs an image pickup signal (also referred to as an image signal).

The image pickup element 102 has an AF evaluation value detection unit 1021. [ The AF evaluation value detection section 1021 detects an AF evaluation value (autofocus evaluation value) at a timing controlled by the control section 106 based on the contrast information and the phase difference information obtained in accordance with the image signal obtained by the image pickup device 102 do. The AF evaluation value detection section 1021 outputs the corresponding AF evaluation value to the control section 106. [

Under the control of the control unit 106, the signal processing unit 104 performs signal processing such as white balance adjustment processing, color correction processing, and automatic exposure (AE) processing on the image signal output from the image pickup element 102 And outputs the image signal as image data.

The compression decompression unit 105 under the control of the control unit 106 compresses (compresses) the image data output from the signal processing unit 104 by a predetermined still image data format such as JPEG (Joint Photographic Coding Experts Group) And performs encoding processing. The compression decompression unit 105 performs decompression decoding processing of the coded image data sent from the control unit 106. [

Further, the compression / expansion unit 105 may perform compression encoding / decompression decoding processing on moving image data by the MPEG (Moving Picture Experts Group) method.

The control unit 106 is a microcontroller having a central processing unit (CPU), a read only memory (ROM), and a random access memory (RAM), for example. The CPU executes the program stored in the ROM to comprehensively control the entire imaging apparatus 100.

When it is determined that the exposure value of the subject is low due to the AE process performed by the signal processing unit 104, the light emitting unit 107 emits light to illuminate the subject. As the light emitting portion 107, for example, a strobe device using a xenon tube or an LED light emitting device may be used.

The operation unit 108 has various operation keys, such as a shutter release button, a lever, and a dial, for example, and gives an operation signal corresponding to a user's input operation to the control unit 106. [

The image display unit 109 includes a display device such as a liquid crystal display (LCD) and an interface circuit for the LCD, and displays an image corresponding to the image data sent from the control unit 106 on the display device .

The image recording unit 110 is a recording medium such as a portable semiconductor memory, an optical disk, a hard disk drive (HDD), or a magnetic tape, for example. The image recording unit 110 compresses and compresses image data compressed by the compression / I remember. The image recording unit 110 also reads out the image file designated by the control unit 106 and outputs it to the control unit 106. [

The basic operation of the image pickup apparatus 100 shown in Fig. 1 will now be described.

For example, as a preparatory operation for capturing a still image, the image pickup element 102 performs CDS processing and AGC processing on the image signals output from the pixel 201 in sequence. Thereafter, the image signal is converted from the A / D converter into a digital image signal. The obtained digital image signal is output to the AF evaluation value detection unit 1021 and the signal processing unit 104. [

The AF evaluation value detection section 1021 calculates an AF evaluation value (control information) in accordance with the contrast information obtained from the digital image signal, and outputs the AF evaluation value to the control section 106. [ The control unit 106 determines the control amount of the mechanical optical unit 1011 based on the AF evaluation value, and controls the driving unit 103 in accordance with the control amount. As a result, the mechanical optical portion 1011 is driven by the driving portion 103. [

The signal processing unit 104 generates a camera through image signal by executing, for example, image quality correction processing on the digital image signal, and outputs the camera through signal to the image display unit 109 ). As a result, the image display unit 109 can display the camera through image corresponding to the camera through image signal, so that the user can adjust the angle of view while viewing the camera through image.

In this state, when the shutter release button of the operation unit 108 is pressed, an image pickup signal (digital image signal) for one frame from the image pickup device 102 is received by the signal processing unit 104 under the control of the control unit 106 . The signal processing unit 104 performs image quality correction processing on the digital image signal for one frame and sends the processed digital image signal (image data) to the compression expansion unit 105. [

The compression decompression unit 105 compresses the image data and sends the encoded image data to the image recording unit 110 via the control unit 106. [ As a result, an image file related to the captured still image is recorded in the image recording section 110. [

When reproducing the image file recorded in the image recording unit 110, the control unit 106 reads the selected image file from the image recording unit 110 in accordance with the operation input from the operation unit 108. [ Then, the control unit 106 sends the image file to the compression / decompression unit 105 that executes the decompression decoding process.

The decoded image data is sent to the image display unit 109 via the control unit 106. [ As a result, the still image corresponding to the image data is reproduced and displayed on the image display section 109. [

The digital image signal outputted from the image sensing element 102 under the control of the control section 106 is received in the signal processing section 104. In this case, The image data sequentially processed by the signal processing unit 104 is compression-encoded by the compression unit 105. [ Thereafter, the moving image data encoded by the compression / expansion unit 105 is sequentially transferred to the image recording unit 110 and recorded as a moving image file.

The control unit 106 reads the selected moving image file from the image recording unit 110 in accordance with an operation input from the operation unit 108. The control unit 106 reads the moving image file recorded in the image recording unit 110, Then, the control unit 106 sends the moving image file to the compression / expansion unit 105 that executes the decompression decoding process. The decoded moving image data is sent to the image display unit 109 via the control unit 106. [ As a result, the moving image corresponding to the moving image data is reproduced and displayed on the image display section 109. [

Now, a description will be given of a technique for displaying a display image while calculating an evaluation value from a captured image in a conventional image pickup apparatus, and problems related thereto. In order to obtain the positional information of the subject used in the focus control in the conventional image pickup apparatus, the positional information is obtained in accordance with the image signal output from the image pickup element. Further, an optical signal is directly input from a subject to a dedicated detection device, and the positional information is obtained by using a phase difference in an image represented by the optical signal. In the case where position information is obtained in accordance with the image signal, a dedicated detection device is unnecessary, so that the image pickup apparatus can be downsized.

10 is an explanatory diagram showing the timing of an autofocus imaging operation (AF evaluation imaging) for a live view in a conventional imaging apparatus.

In the conventional imaging apparatus, the imaging timing is defined by a vertical driving pulse (VD). When the AF control signal is turned on, an AF evaluation image is captured in accordance with VD after the live view imaging period. When the AF control signal is turned off, the live view imaging period starts again.

In this way, since the live view imaging period for obtaining the live view image and the AF operation period for obtaining the AF evaluation image exist in series along the time axis, it is not possible to simultaneously capture the live view image and the AF evaluation image.

Therefore, as shown in the figure, the AF evaluation image is captured during the AF operation period located between the live view periods (frames). Therefore, there is a time delay between the live view image and the AF evaluation image.

Incidentally, even when capturing an AF evaluation image, live view display is performed, but in this case, live view display is performed according to the AF evaluation image. As shown in Fig. 10, when capturing an AF evaluation image, the frame rate is higher than the live view image capture period. As a result, in the reading of the image pickup device, the screening rate is increased and inevitably the image quality is lowered. In order to avoid this problem, some of the imaging elements have, for example, a pixel portion for setting the focus signal detection pixel separately from the imaging signal pixel.

In the present embodiment, an image pickup device 102 as shown in Figs. 2A and 2B is provided in view of the above problems. The image pickup element 102 is configured to generate control information based on the evaluation value obtained from the image signal or the evaluation value thereof in parallel with the image signal for display, thereby shortening the processing time and reducing the processing load.

2A and 2B are explanatory diagrams showing the configuration of the imaging element 102 shown in Fig. 2A is a perspective view showing a structure of an image pickup device 102, and FIG. 2B is a block diagram showing the structure thereof.

In Fig. 2A, the image pickup device 102 has a first chip (pixel portion) 20 and a second chip 21. A first chip (first element portion) 20 is laminated on a second chip (second element portion) 21. The first chip 20 having a plurality of pixels 201 arranged in a matrix shape is disposed on the light incident side (that is, on the light receiving side of the optical image).

The second chip 21 is formed with a pixel driver provided thereon with column scanning circuits 213-a and 213-b and a column scanning circuit 212 described later. The above-described AF evaluation value detector (control information generator) 1021 is also formed on the second chip 21.

Since the pixel 201 is formed on the first chip 20 and the pixel driver and the AF evaluation value detecting section 1021 are formed on the second chip 21 in this way, Process can be distributed. Therefore, the tendency toward thinning and densification of wirings in peripheral circuits can realize high speed, small size, and high performance.

As shown in Fig. 2B, in the first chip 20, the pixels 201 are arranged in a matrix shape. Each of the pixels 201 is connected to the transfer signal line 203, the reset signal line 204 and the row select signal line 205 in the horizontal direction (row direction), and the column signal line 202-a And 202-b. At this time, the column signal lines 202-a and 202-b are connected to each other in units of read rows.

As shown in the figure, each of the pixels 201 has a photodiode PD as a photoelectric conversion element, a transfer transistor Ml, a reset transistor M2, an amplification transistor M3, a selection transistor M4, and a floating diffusion FD.

In the example shown in the figure, each of the transistors is an n-channel MOS field effect transistor (MOS FET).

A transfer signal line 203, a reset signal line 204, and a row select signal line 205 are connected to the gates of the transfer transistor Ml, the reset transistor M2, and the select transistor M4, respectively. These signal lines 203 to 205 extend in the horizontal direction, and the pixels on the same line are simultaneously driven. Thereby, the operation of the rolling shutter of the line sequential operation type can be controlled, and the image can be captured while changing the exposure time for each predetermined row. Alternatively, it is possible to control the operation of the global shutter of the all-row simultaneous operation type.

Furthermore, the source of the selection transistor M4 is connected to the column signal line 202-a or 202-b on the row.

The photodiode PD accumulates the charges generated by the photoelectric conversion. The P side of the photodiode PD is grounded and the N side is connected to the source of the transfer transistor M1. When the transfer transistor M1 is turned on, the charge of the photodiode PD is transferred to the FD. Since the parasitic capacitance exists in the FD, the charges transferred to the FD are accumulated.

The power supply voltage Vdd is applied to the drain of the amplifying transistor M3, and the gate of the amplifying transistor M3 is connected to the FD. The amplifying transistor M3 amplifies the charge (i.e., voltage) of the FD and converts it into a voltage signal. The selection transistor M4 is for selecting a pixel for reading a signal on a row. The drain of the selection transistor M4 is connected to the source of the amplifying transistor M3. The source of the selection transistor M4 is connected to the column signal line 202. [

When the selection transistor M4 is turned on, a voltage signal corresponding to the voltage of the FD is outputted to the column signal line 202. [ A power supply voltage Vdd is applied to the drain of the reset transistor M2, and the source of the reset transistor M2 is connected to the FD. When the reset transistor M2 is turned on, the voltage of the FD is reset to the power supply voltage Vdd.

The second chip 21 includes a column ADC block 211, which is connected to the column signal line 202-a or 202-b. The second chip 21 is provided with a row scanning circuit 212, column scanning circuits 213-a and 213-b, a timing control unit 214, horizontal signal lines (output units) 215-a and 215- ), A frame memory 217, and an AF evaluation value detecting section 1021. [

The timing controller 214 controls the operation timings of the column scan circuit 212, the column scan circuits 213-a and 213-b, and the column ADC block 211 under the control of the control unit 106. [ The row scanning circuit 212 scans each row, and the column scanning circuits 213a and 213b scan each column.

The horizontal signal lines 215-a and 215-b transmit output signals (image signals) of the column ADC block 211 in accordance with the timings controlled by the column scanning circuits 213-a and 213-b, respectively.

The frame memory 217 temporarily stores image signals output from the horizontal signal line 215-b. The AF evaluation value detection section 1021 performs AF evaluation in accordance with the image signal stored in the frame memory 217 and sends the AF evaluation value to the control section 106. [

The changeover switch 216 is a switch for selectively outputting the image signal output to the horizontal signal line 215-b to either the AF evaluation value detection unit 1021 or the signal processing unit 104. [

At this time, the image signal transmitted to the horizontal signal line 215-a is given to the signal processing unit 104. [

Fig. 3 is an explanatory diagram showing pixel selection in the column signal line 202-a or 202-b in the first chip 20 shown in Figs. 2A and 2B.

Fig. 3 shows a pixel portion of 6 rows x 8 columns, where each pixel is arranged according to a Bayer arrangement.

When the focus control mode is turned on by the operation of the operation unit 108 shown in Fig. 1, the control unit 106 divides the reading row in the imaging element 102 (i.e., controls the switching of the selector switch 216, The horizontal signal line 215-b is connected to the frame memory 217). Therefore, the live view imaging (second imaging mode) and the AF evaluation value detection imaging (first imaging mode) can be performed at the same time.

Thus, an image signal for a live view (second image signal, that is, an image display signal) is output to the column signal line 202-a, and an image signal for AF evaluation detection (first image signal) do.

In Fig. 3, row numbers 1 and 2 are rows (first pixel group) for AF evaluation value detection imaging, and row numbers 3 to 8 are rows (second pixel group) for live view imaging. In the example shown in the figure, read-out scanning is performed sequentially on a row-by-row basis, and read-out scanning is repeatedly performed on the 8th row.

In the AF evaluation value detection imaging, three pixels (three lines out of four lines) among the four pixels of the vertical same color are selected for reading because of the importance of the frame rate. On the other hand, in the imaging for live view, one pixel (one line out of four lines) of the remaining four pixels of the same vertical color is selected for image quality, and three pixels are added.

In other words, in the AF evaluation value detection imaging, the first pixel group is read at the first frame rate. In live view imaging, the second pixel group is read at a second frame rate which is slower than the first frame rate.

As described above, by dividing the AF scanning imaging and the live view imaging for each selected row, it is possible to acquire an image signal having a different data size at different charge accumulation time.

Next, the voltage signal (analog signal) output to the column signal lines 202-a and 202-b is converted from an analog signal to a digital signal (image signal) in the column ADC block 211 shown in Fig. 2B.

The image signal which is the output of the column ADC block 211 is read out from the column ADC block 211 to the horizontal signal line 215-a or 215-b by the column scanning circuit 213-a or 213-b. The image signal read to the horizontal signal line 215-a is sent to the signal processing unit 104. [

On the other hand, the image signal read out to the horizontal signal line 215-b is output to the switch 216 and outputted to the signal processing unit 104 or the frame memory 217 under the control of the control unit 106. [ At this time, the changeover switch 216 is switched on a frame-by-frame basis.

In this case, since the pixel signal is read without taking a picture in the still image shooting, the switch 216 is switched to the path connected to the signal processing unit 104. [

On the other hand, in the AF evaluation mode (i.e., the autofocus control mode), an image signal is recorded from the horizontal signal line 215-b to the frame memory 217 via the changeover switch 216, The AF evaluation value is detected based on the contrast information in the image signal recorded on the recording medium 217. The AF evaluation value is the focus information of the subject. The focus information is composed of contrast information, defocus movement amount in the AF mechanism section in the mechanical optical section 1011, or control information of the AF mechanism section. The AF evaluation value is sufficiently small in terms of the data amount as compared with the image data for the AF evaluation value of the plurality of pixels. This AF evaluation value is sent from the AF evaluation value detection section 1021 to the control section 106. [

Thus, in this embodiment, the AF evaluation value detection section 1021 is embedded in the chip 21 to achieve power saving, high-speed processing, and low-cost design. In most cases, the chip 21 and the signal processing unit 104 or the control unit 106 are disposed on separate substrates, and the resistance component and the capacitance component of the wiring are increased in the inter-chip communication. As a result, the communication speed is lowered as compared with the communication in the wiring in the chip. In order to transmit a high-speed signal, it is necessary to drive it with an amplifier in order to maintain the signal waveform quality.

In this embodiment, since the AF evaluation value detecting section 1021 is disposed together with the chip 21 on the same semiconductor chip, the output line of the image data can be made shorter and the arrangement of the amplifiers can be omitted . In addition, since the AF evaluation value itself has a small amount of data, the time taken for communication between the image pickup device 102 and the control unit 106 is shortened, and consequently power consumption can be reduced.

In the following description, an output path by the column signal line 202-a and the horizontal signal line 215-a is called a channel Ch1, and an output path by the column signal line 202-b and the horizontal signal line 215-b is called a channel Ch2 .

4 is a timing chart for explaining the imaging timing in the AF evaluation mode in the camera 100 shown in Fig.

As shown in Fig. 4, the imaging timing is defined by the vertical synchronization signal VD. When the AF evaluation mode is turned on, the control unit 106 simultaneously starts the AF control signal at the falling edge of the vertical synchronization signal VD at time T0, the live view imaging using the channel Ch1, and the AF evaluation imaging using the channel Ch2 do.

The AF evaluation image signal read from the pixel portion 20 through the channel Ch2 in the periods T0 to TF1 is stored in the frame memory 217 via the horizontal signal line 215-b and the changeover switch 216. [ Thereafter, in the periods TF1 to TF2, the AF evaluation value detection section 1021 detects the AF evaluation value in accordance with the AF image signal stored in the frame memory 217. [ Thereafter, in the periods TF2 to TF3, the AF evaluation value detection section 1021 outputs the AF evaluation value to the control section 106. [

In the example shown in the figure, during the period of one vertical synchronizing signal VD, live view is taken for one frame, and AF evaluation (AF scanning) for three frames. When the control section 106 sets the vertical synchronization signal VD to the L level (time T1), the AF evaluation is ended.

As described above, in the AF evaluation mode, the camera 100 shown in Fig. 1 does not need to send the image data to the control unit 106 via the signal processing unit 104 to obtain the AF evaluation value. In other words, the AF evaluation value with a small amount of data is directly output from the image pickup element 102 to the control section 106. [ Therefore, the load can be reduced and the power consumption can be reduced.

The control unit 106 compares the AF evaluation value with a predetermined AF expectation value to be described later, and when the AF evaluation value satisfies the AF expectation value, the AF control signal is lowered (time T1). When the AF control signal is lowered, only AF evaluation imaging stops, and live view imaging continues.

Fig. 5 is a flowchart for explaining control in the camera 100 shown in Fig. At this time, the flowchart shown in the figure is performed under the control of the control unit 106. [

When the power of the camera 100 is on and the standby state (that is, the imaging preparation state before imaging) is reached, the control unit 106 determines whether the AF evaluation mode is executed (step S502). That is, the control unit 106 determines whether or not the autofocus mode is set.

If the AF evaluation mode is not performed (NO in step S502), the control unit 106 starts live view imaging (step S503) and proceeds to step S515 described later.

If it is determined that the AF evaluation mode is to be executed (YES in step S502), the control unit 106 turns on the AF control signal (H level) (step S504). Next, the control unit 106 substitutes 0 for the variable n for counting the AF evaluation imaging count (step S505).

Next, as described in Fig. 4, the control unit 106 starts AF evaluation imaging (step S506), and also starts live view imaging in step S516.

After AF evaluation imaging is started, the control unit 106 increments the variable n by 1 (step S507). Thereafter, under the control of the control unit 106, the AF evaluation value detection unit 1021 detects the AF evaluation value AF_K in accordance with the AF evaluation image signal obtained by the AF evaluation imaging (step S508).

Next, the control unit 106 determines whether or not the AF evaluation value AF_K satisfies the following equation (1), that is, the predetermined evaluation condition, with respect to the AF expected values K_min and K_max (step S509).

K_min < AF_K < K_max (1)

Here, the AF expected values K_min and K_max represent the minimum and maximum values of the expected AF evaluation values and are recorded in advance in the control unit 106 at the time of designing the camera 100 or at the time of adjustment of the camera 100. [

If the AF evaluation value AF_K does not satisfy the formula (1) (NO in step S509), the control section 106 obtains the feedback control amount in accordance with the AF evaluation value AF_K. Thereafter, the control unit 106 drives the drive unit 103 in accordance with the feedback control amount to drive the focus lens provided in the mechanical optical unit 1011 along the optical axis (step S510).

Next, the control unit 106 judges whether or not the variable (the number of times AF evaluation value imaging) n is a predetermined number (3 in this case) (step S511). If the number of times of AF evaluation value imaging is less than 3 (NO in step S511), the control unit 106 returns to the process of step S506 to perform AF evaluation imaging.

If the number of times of AF evaluation value imaging is 3 (YES in step S511), the control unit 106 performs live view display (step S512) and returns to the process of step S505 to set the number of times AF evaluation value imaging n to zero do.

If the AF evaluation value AF_K satisfies the equation (1) (YES in step S509), the control section 106 turns off the AF control signal (L level) (step S513) AF evaluation imaging is stopped (step S514). Thereafter, the control unit 106 displays an image corresponding to the captured live view image signal on the image display unit 109 (step S515), and the camera is in the standby state (step S517).

In the flowchart shown in Fig. 5, after the AF evaluation imaging is stopped, the control unit 106 displays an image corresponding to the image signal obtained by the live view imaging in step S516. When the live view imaging of step S503 is started, the control unit 106 proceeds to the process of step S515 to perform live view display.

As described above, in the first embodiment of the present invention, the AF evaluation value detector 1021 is provided in the second chip 21. [ Thus, while the live view image is being captured, the image pickup of the AF evaluation image with a high frame rate and the AF evaluation value can be calculated and output. As a result, the time delay in performing the AF evaluation can be shortened.

In addition, in the AF evaluation, only the AF evaluation value with a small data capacity is sent from the image sensing element 102 directly to the control section 106, so that the signal output load can be reduced and the power consumption can be reduced.

Although the above embodiment has been described with respect to an example in which AF is performed in Live View, the above method can be used not only in live view but also in other moving images.

In the present embodiment, the AF evaluation value is directly output from the image pickup element 102 to the control section 106, and the control section 106 controls the mechanical optical section 1011 by the drive section 103 in accordance with the AF evaluation value do. However, the driving section 103 may drive-control the mechanical optical section 1011 in accordance with the AF evaluation value.

Second Embodiment

Now, an example of the camera of the second embodiment of the present invention will be described.

The configuration of the camera in the second embodiment is the same as that shown in Fig. 1 except that the configuration of the imaging device 102 is different from that of the imaging device shown in Fig. 2B. In the following description, the still image photographing for the photometric operation by the light emitting portion such as the strobe will be described.

6 is a block diagram showing an example of the configuration of an image pickup device used in a camera according to the second embodiment of the present invention.

Here, in Fig. 6, the same reference numerals are attached to the same constituent elements as those of the imaging element shown in Fig. 2A, and a description thereof will be omitted.

6, the second chip 21 includes a photometric value evaluation unit 601 instead of the AF evaluation value detection unit 1021. [ The photometric value evaluation unit 601 is connected to the frame memory 217 and is connected to the control unit 106. [

The photometric value evaluating unit 601 calculates the color ratio and the exposure value as a photometric value in accordance with the image signal read from the first chip 20 via the column signal line 202-b and the horizontal signal line 215b (i.e., the channel Ch2) . The photometric evaluation unit 601 outputs the photometric data such as the white balance coefficient and the light emission control amount of the light emitting unit 107 to the control unit 106 in accordance with the photometric value.

The control unit 106 sends a control command to the signal processing unit 104 and the light emitting unit 107 in accordance with the light metering control data and controls the white balance correction in the signal processing unit 104 and the amount of light emitted by the light emitting unit 107.

7 is a timing chart for explaining the imaging timing in the photometric evaluation mode in the second embodiment of the present invention.

In the photometric evaluation mode, the control unit 106 simultaneously starts live view imaging using the channel Ch1 and photometric evaluation imaging using the channel Ch2 in synchronization with the vertical synchronization signal VD at the falling edge of the vertical synchronization signal VD at time T70. In this photometric evaluation imaging, the white balance coefficient and photometric evaluation imaging for light emission control of the light emitting portion 107 are performed.

Here, the photometric evaluation imaging calculation for calculating the white balance coefficient is referred to as a white balance coefficient calculating imaging, and the photometric evaluation imaging for emission control is referred to as a light emission control amount photometric imaging.

First, in the period T70 to T71, the white balance coefficient calculation imaging is performed. The white balance coefficient evaluation image signal read from the pixel portion 20 via the channel Ch2 is stored in the frame memory 217 via the horizontal signal line 215-b and the changeover switch 216. [

In the periods T71 to T72, the photometric value evaluation unit 601 calculates the white balance coefficient in accordance with the image signal for white balance coefficient evaluation stored in the frame memory 217. [ Thereafter, in the period T72 to T73, the photometric value evaluation unit 601 outputs the white balance coefficient to the control unit 106. [

Next, at time T73, the control unit 106 starts the light emission control signal (H level) and starts light emission control amount photometric imaging while causing the light emission unit 107 to emit light with a predetermined light emission amount. Thereafter, at time T74, the control section 106 lowers the light emission control signal (to the L level) to stop the light emission control amount photometric imaging.

Therefore, in the period T73 to T74, the light emission control amount of the light emitting portion 107 in the still image shooting is photographed, and the image signal for evaluation of the light emission control amount is stored in the frame memory 217. [

In the period T73 to T74, since the light emission control signal is turned on, preliminary light emission (that is, preliminary light emission) by the light emission section 107 is performed and light emission control amount photometric imaging, which is the imaging for calculating the exposure amount of the subject, Is done.

In the periods T74 to T75, the photometric value evaluation unit 601 calculates an exposure value related to the subject in accordance with the image signal for evaluation of the light emission control amount stored in the frame memory 217. [ Based on the exposure value, the metering value evaluation unit 601 generates the light emission control amount. Next, in the periods T75 to T76, the photometric value evaluating section 601 outputs the photometric value to the light emission control amount control section 106. [

At time T76, the control unit 106 switches the photometric evaluation mode to the still image photographing mode, and turns on the light emission control signal to cause the light emitting unit 107 to emit light (main light emission). At this time, the control unit 106 controls the light emission amount of the light emitting unit 107 according to the light emission control amount.

The control unit 106 changes the changeover switch 216 and outputs the image signal output through the channel Ch2 to the signal processing unit 104 and outputs the image signal read out from all the pixels of the pixel unit 20 to the signal processing unit 104. [ (104).

In the example shown in the drawing, the live view is taken for one frame in the period of one vertical synchronizing signal VD. During this period, white balance coefficient calculation imaging, calculation and output of white balance coefficient, light emission control amount light metering imaging, calculation and output of light emission control amount are performed.

As described above, in the second embodiment of the present invention, the AF evaluation value detecting section 1021 is provided in the second chip 21, so that a live view image can be captured, And the metering evaluation value can be calculated and output. As a result, the time delay in the photometric evaluation can be shortened.

In the photometric evaluation, only the photometric evaluation value (white balance coefficient and light emission control amount) with a small data capacity is sent from the image sensing element 102 directly to the control section 106. [ As a result, the signal output load is reduced, and the power consumption can be reduced.

In the embodiment described above, the photometric evaluation value is directly input from the imaging element 102 to the control unit 106, and the control unit 106 controls the signal processing unit 104 and the light emitting unit 107 in accordance with the photometric evaluation value. However, the photometric evaluation value may be directly sent to the signal processing unit 104 and the light-emitting unit 107 from the imaging device 102. [

Third Embodiment

Next, an example of the camera in the third embodiment of the present invention will be described.

The configuration of the camera in the third embodiment is the same as that shown in Fig. 1 except that the configuration of the imaging device 102 is different from that of the imaging device shown in Fig. 2B.

8 is a block diagram showing an example of the configuration of an image pickup device used in a camera according to the third embodiment of the present invention.

Here, in Fig. 8, the same structural elements as those of the imaging element shown in Figs. 2A and 6 are denoted by the same reference numerals, and a description thereof will be omitted.

8, the second chip 21 includes an image signal evaluation unit 801 instead of the AF evaluation value detection unit 1021. The image signal evaluation unit 801 shown in FIG. The image signal evaluation section 801 is connected to the frame memory 217 and is connected to the control section 106.

The image signal evaluation unit 801 calculates a standard deviation (also referred to as a standard deviation value) indicating a signal variation according to an image signal read from the first chip 20 via the column signal line 202-b. Thereafter, the image signal evaluation unit 801 outputs the standard deviation to the control unit 106 as an image signal evaluation value. The control unit 106 sends an imaging control signal for controlling the amount of gain-up or the amount of exposure (that is, the exposure period) to the driving unit 103 when the standard deviation exceeds a predetermined threshold (standard deviation threshold) . The driving unit 103 drives the imaging element 102 in accordance with the imaging control signal to perform exposure control. This is because it is effective to limit the exposure control to maintain the predetermined image quality by indicating the deterioration of the S / N ratio in the image signal if the standard deviation exceeds a predetermined threshold value.

In the example shown in Fig. 8, a predetermined image quality is maintained by exposure control. However, the present invention is not limited to the exposure control, and the predetermined image quality may be maintained, for example, by changing the correction value in the noise reduction processing. Furthermore, in the example shown in the figure, the image signal evaluation unit 801 is configured to output an image signal evaluation value that is a standard deviation. However, the image signal evaluation unit 801 may be configured to output a control signal corresponding to the standard deviation to the drive unit 103, the signal processing unit 104, or the light emission unit 107 to maintain a predetermined image quality.

9 is a timing chart for explaining the imaging timing in the standard deviation evaluation mode in the third embodiment of the present invention.

When the camera enters the standard deviation evaluation mode, the control unit 106 starts imaging at the falling edge of the vertical synchronization signals VD1 and VD2 at time T90. Here, the control unit 106 starts live view imaging using the channel Ch1 in synchronization with the vertical synchronization signal VD1 and standard deviation evaluation imaging (also referred to as image signal evaluation imaging) using the channel Ch2 in synchronization with the vertical synchronization signal VD2 .

In the live view imaging in synchronization with the vertical synchronization signal VD1, the imaging operation is performed in accordance with the frame rate for the live view display. Live view imaging of a plurality of frames is performed in one VD period (T90 to T93) related to the vertical synchronization signal VD2.

Evaluation of Image Signal in Period T90 to T91 In the image sensing, the standard deviation detecting image signal read in the channel Ch2 is read out from the image sensing element 102. [ The setting in the period T90 to T91 is the same as the setting in the exposure period in the still image pickup after the time T93. The exposure control after the time T93 is determined according to the user operation using the operation unit 108 or the AE control corresponding to the image signal obtained from the image pickup device 102. [ Therefore, in the image signal evaluation imaging in the channel Ch2, exposure control different from the exposure control for the live view display in the channel Ch1 is performed.

Furthermore, in the channel Ch2, by performing the same exposure control as the still image pickup after the time T93, the deterioration of the S / N ratio due to the signal amplification, which is a deterioration factor of the image quality before the still image pickup, can be restricted. Further, imaging control such as long accumulation operation of the imaging pixels can be restricted. As a result, deterioration of the image quality of the still image to a predetermined level or more can be prevented.

The output of the channel Ch2 obtained as a result of imaging in the period T90 to T91, that is, the image signal for standard deviation detection, is stored in the frame memory 217 via the horizontal signal line 215-b and the switch 216. [ The standard deviation detecting image signal stored in the frame memory 217 is read to the image signal evaluating section 801 and the image signal evaluating section 801 evaluates the signal fluctuation Lt; / RTI &gt;

Thereafter, in the period T92 to T93, the image signal evaluation section 801 outputs only the standard deviation value calculated in the period T91 to T92 from the image sensing element 102 to the control section 106. [ After time T93, the camera changes from the standard deviation evaluation mode to the still image shooting mode. The control unit 106 can switch the switch 216 to enable the image signal to be output to the signal processing unit 104 so that all the pixels can be read. In this case, the control unit 106 performs exposure control according to the standard deviation value calculated by the image signal evaluation unit 801. [

As described above, the third embodiment of the present invention is configured to simultaneously capture an image signal for live view and an image signal for evaluation. Accordingly, the standard deviation value for controlling the operation in the still image sensing can be detected before the actual sensing before the sensing of the still image.

Furthermore, the third embodiment is configured to output the standard deviation value, which is an image signal evaluation value with a small amount of data, to the direct control section 106. [ Accordingly, there is no need to send an image signal having a large data amount from the image pickup device 102 to the signal processing unit 104 any more. As a result, it is possible to reduce the power by reducing the load caused by the signal output.

Thus, in the third embodiment of the present invention, the image pickup device 102 acquires an image signal simultaneously in the image pickup period different from the image pickup period for live view, but the image pickup operation is different from the live-view image pickup operation. In accordance with the acquired image signal, the standard deviation value, which is an image signal evaluation value, is calculated by the image pickup element 102 and outputted to the control section 106. [ As a result, the evaluation value of the image signal can be obtained during the live view mode, thereby saving power and time.

In the third embodiment, an example of calculating the standard deviation value related to the image signal is described. The evaluation value shown below is calculated by the image signal evaluation section 801, and the corresponding correction is sent to the control section 106 .

(1) The image signal offset correction value, which is the variation per frame of the offset component used as the image signal reference value, may be calculated from the image signal. (2) Striped fixed pattern noise in a column or row unit may be detected. (3) A flicker may be detected by setting exposure conditions different from the conditions of moving image recording or live view display and detecting a change in the light source output. (4) the WB coefficient, (5) the amount of movement of the subject, and (6) the vector amount to calculate the hand shake correction value or the motion detection value of the subject. (8) a luminance shading evaluation value, and (9) a flicker evaluation value to calculate exposure control based on the shutter control of the diaphragm mechanism section and the imaging element 102 in the mechanical optical section 1011 May be performed.

It will be appreciated that each of the evaluation values may be acquired and corrected by the above-described methods as well as other known methods.

As apparent from the above description, in the example shown in Fig. 1, the control section 106 and the drive section 103 function as a control section and a read control section. The control unit 106 and the image display unit 109 also function as a display control unit.

Although the present invention has been described based on the above embodiments, the present invention is not limited to these embodiments, and various aspects derived from the scope and spirit of the present invention are also included in the present invention.

For example, the functions of the above embodiments may be used as the control method, or the control method may be executed by the image pickup apparatus. Further, a program having the functions of the above embodiments may be used as a control program, or the control program may be executed by a computer provided with the image pickup apparatus. For example, the control program is recorded on a computer-readable recording medium.

Each of the control method and the control program includes at least a control step and a display control step.

Further, the present invention can also be realized by executing the following processing. That is, the software (program) for realizing the functions of the above-described embodiments is supplied to the system or apparatus via the network or various recording media. The system or a computer (or a device such as a CPU and an MPU) of the system reads and executes the program.

According to the present invention, the control information used only for the control of the focus control or the like is output from the image pickup element when performing the control. Therefore, it is possible to shorten the data transfer time and avoid deterioration of image quality.

Fourth Embodiment

11 is a block diagram showing a configuration example of an image pickup apparatus according to the fourth embodiment of the present invention. The imaging device shown in the drawing is applied to, for example, an electronic still camera or a video camera with a moving image function.

11, the image capturing apparatus 1100 includes a lens 1101, an image sensor 1102, an image signal processing section 1103, a compression expanding section 1104, a lens drive control section 1105, an imaging evaluation value detecting section 1106 ), A scene discrimination unit 1107, and a system control unit 1108. [ The image capturing apparatus 1100 further includes a light emitting portion 1109, an operation portion 1110, a storage portion 1111, and a display portion 1112.

The lens 1101 is a lens group constituting a photographing optical system. Inside the lens 1101, a focus lens is included. This focus lens is a focus adjustment lens. The focus lens is configured so that its position can be changed along the optical axis direction. The lens drive control section 1105 has a function as a focus adjustment section for performing drive control of the focus lens based on the value detected by the image pickup evaluation value detection section 1106 and executing focus adjustment processing. The light having passed through the lens 1101 is focused on the image plane of the image sensor 1102 composed of a CMOS image sensor or the like as an optical image of the subject. Thereafter, the optical image is photoelectrically converted into a pixel signal from a pixel 1201 to be described later.

The image sensor 1102 has a pixel 1201 and an A / D converter. For example, the image sensor 1102 is a so-called XY read CMOS type image sensor. Under the control of the system control section 1108, the image sensor 1102 performs imaging operations such as exposure, signal reading and resetting, and outputs an imaging signal (also referred to as an image signal).

The imaging evaluation value detection section 1106 detects the imaging evaluation value from the image signal output from the image sensor 1102. [ In this case, the imaging evaluation value is detected at the timing outputted from the system control section 1108. [ The detailed operation will be described later.

Here, the imaging evaluation value is a parameter necessary for controlling the imaging apparatus and correcting the photographed image. For example, the imaging evaluation value is an evaluation value necessary for the basic operation of the imaging apparatus such as an AF evaluation value, a white balance (WB) evaluation value, and an automatic exposure (AE) evaluation value. The AF evaluation value is an evaluation value for focusing on a subject at the time of image capture, and is mainly necessary for controlling the focus lens. The WB evaluation value is an evaluation value necessary for correcting the color at the time of image capture and is also a parameter required at the time of development. The AE evaluation value is an evaluation value required to obtain an appropriate exposure at the time of photographing. The AE evaluation value is mainly required to set the aperture, the shutter speed and the sensitivity.

The system control section 1108 determines the control amount of the lens 1101 based on the AF evaluation value of one of the parameters obtained as the imaging evaluation value and outputs the control amount to the lens drive control section 1105. [ The lens drive control section 1105 drives the lens 1101 in the direction of the optical axis based on the control amount of the AF evaluation value obtained from the system control section 1108 to adjust the focus of the subject.

Under the control of the system control section 1108, the image signal processing section 1103 performs signal processing on the image signal output from the image sensor 1102 to generate image data. More specifically, based on the imaging evaluation values detected by the imaging evaluation value detection section, signal processing such as white balance adjustment processing, color correction processing, and AE processing is performed to generate image data.

The compression decompression unit 1104 operates under the control of the system control unit 1108 and performs compression encoding processing on the image data output from the image signal processing unit 1103 in a predetermined still image data format. For example, the predetermined still image data format is JPEG (Joint Photographic Coding Experts Group). The compression decompression unit 1104 performs decompression decoding processing on the coded image data sent from the system control unit 1108. [ Further, the compression / expansion unit 1104 may perform compression encoding / decompression decoding processing on moving image data by the MPEG (Moving Picture Experts Group) method or the like.

The scene discrimination unit 1107 discriminates the shooting scene based on the shooting condition obtained from the system control unit. And sends information to the system control unit 1108 to change parameters such as photographing parameters and image processing parameters for photographing in accordance with the determined photographing scene. Here, the imaging evaluation value detection section 1106 determines, based on the information on the scene discrimination, which imaging evaluation value is to be detected from the imaging evaluation value detection image signal or the display image signal as described later.

The system control unit 1108 is a microcontroller including, for example, a central processing unit (CPU), a read only memory (ROM), and a random access memory (RAM). The CPU of the system control section 1108 executes a program stored in the ROM to comprehensively control the entire image capturing apparatus 1100.

If it is determined that the exposure value of the subject is low in the AE process performed by the image signal processing unit 1103, the light emitting unit 1109 illuminates the subject to perform illumination. As the light emitting portion 1109, for example, a strobe device using a xenon tube or an LED light emitting device may be used. The operation unit 110 has various operation keys, such as a shutter release button, a lever, and a dial, for example, and gives an operation signal corresponding to a user's input operation to the system control unit 1108. [

The recording unit 1111 is a recording medium such as a portable semiconductor memory, an optical disk, a hard disk drive (HDD), or a magnetic tape, for example, and stores the image data compression- do. The recording unit 1111 also reads out the image file specified by the system control unit 1108 and outputs it to the system control unit 1108. [

The image display unit 1112 includes, for example, a display device such as a liquid crystal display (LCD) and an interface circuit for the LCD, and displays an image represented by image data sent from the system control unit 1108 on the display device .

12A and 12B are explanatory diagrams showing the configuration of the image sensor 1102 shown in Fig. 12A is a perspective view of the image sensor, and FIG. 12B is a block diagram showing the configuration thereof.

12A, the image sensor 1102 has a first chip (first device portion) 120 and a second chip (second device portion) 121, and a second chip 121 120 are stacked. The first chip 120 has a plurality of pixels 1201 arranged in a matrix shape and the first chip 120 is stacked with the pixel array facing the light incident side have). The second chip 121 has a pixel driver including column scanning circuits 1213-a and 1213-b and a row scanning circuit 1212, which will be described later.

By forming the pixel 1201 in the first chip 120 and forming the pixel driver in the second chip 121, the peripheral circuit of the image sensor 1102 and the manufacturing process of the pixel portion can be separated. Therefore, the tendency toward thinning and densification of wirings in peripheral circuits can realize high speed, small size, and high performance.

12B, in the first chip 120, the pixels 1201 are arranged in a matrix shape, and each pixel 1201 is divided into a transfer signal line 1203 in the horizontal direction (row direction) Line 1204 and the row selection signal line 1205, respectively. Further, the pixel 1201 is connected to the column signal lines 1202-a and 1202-b in the vertical direction (column direction). At this time, each of the column signal lines 1202-a and 1202-b is configured to connect the pixel to the other read destination over the row.

Each of the pixels 1201 has a photodiode PD as a photoelectric conversion element, a transfer transistor M1, a reset transistor M2, an amplification transistor M3, a selection transistor M4, and a floating diffusion FD as shown in the figure. In the example shown in the figure, each of the transistors is an n-channel MOS field effect transistor (MOS FET).

A transfer signal line 1203, a reset signal line 1204, and a row select signal line 1205 are connected to the gates of the transfer transistor Ml, the reset transistor M2, and the select transistor M4, respectively. These signal lines 1203 to 1205 are arranged to extend in the horizontal direction, and the pixels in the same row are driven simultaneously. As a result, it is possible to control the operation of the rolling shutter of the line sequential operation type or the global shutter of the all-line simultaneous operation type. Furthermore, the column signal line 1202-a or 1202-b is connected to the source of the selection transistor M4 on the row.

The photodiode PD accumulates the charges generated by the photoelectric conversion. The P side of the photodiode PD is grounded, and the N side is connected to the source of the transfer transistor M1. When the transfer transistor M1 is turned on, the charge of the photodiode PD is transferred to the FD. Since the parasitic capacitance exists in the FD, the charges transferred to the FD are accumulated.

A power supply voltage Vdd is applied to the drain of the amplifying transistor M3, and its gate is connected to the FD. The amplifying transistor M3 amplifies the charge (i.e., voltage) of the FD and converts it into a voltage signal. The selection transistor M4 is for selecting a pixel for reading a signal on the row by the row selection signal line 1205. [ The drain of the selection transistor M4 is connected to the source of the amplifying transistor M3. The source of the selection transistor M4 is connected to the column signal line 1202. [

When the selection transistor M4 is turned on by the row selection signal line 1205, a voltage signal corresponding to the voltage of the FD is output to the column signal line 1202. [ A power supply voltage Vdd is applied to the drain of the reset transistor M2, and the source of the reset transistor M2 is connected to the FD. When the reset transistor M2 is turned on by the reset signal line 1204, the voltage of the FD is reset to the power supply voltage Vdd.

A column ADC block 1211 is provided in the second chip 121 and a column ADC block 1211 is connected to the column signal line 1202-a or 1202-b. A row scanning circuit 1212, column scanning circuits 1213-a and 1213-b, a timing control section 1214 and horizontal signal lines (output sections) 1215-a and 1215 -b) is installed.

The timing control unit 1214 controls the operation timings of the column scan circuit 1212, the column scan circuits 1213-a and 1213-b, and the column ADC block 1211 under the control of the system control unit 1108. [ The row scanning circuit 1212 scans each row, and the column scanning circuits 1213-a and 1213-b scan each column.

The horizontal signal lines 1215-a and 1215-b transmit the output signals (image signals) of the column ADC block 1211 on the basis of timings controlled by the column scanning circuits 1213-a and 1213-b, respectively. As a result, an image signal (second image signal, i.e., an image display signal) for live view is output to the column signal line 1202-a, and an image signal (first image signal) .

13, row numbers 1 and 2 are rows (first pixel group) for image pickup evaluation value detection images, row numbers 3 to 8 are rows (second pixel group) for image pickup of a live view image, to be. In the example shown in the figure, read-out scanning is performed sequentially on a row-by-row basis, and read-out scanning is repeatedly performed on the 8th row.

In the imaging evaluation value detection imaging, three pixels out of four pixels of vertical same color are read out selectively because of the importance of the frame rate. On the other hand, in the image for live view, one pixel out of four vertically-same-color pixels is selected because image quality is important, and three pixels are added. In other words, in the imaging evaluation value detection imaging, the first pixel group is read at the first frame rate. In live view imaging, the second pixel group is read at a second frame rate which is slower than the first frame rate.

As described above, by separating the imaging evaluation value detection imaging and the live view imaging for each selected row, it is possible to acquire an image signal at a frame rate different in data size with different charge accumulation time.

The voltage signals (analog signals) output to the column signal lines 1202-a and 1202-b are converted from analog signals to digital signals (image signals) in the column ADC block 1211 shown in Figs. 12A and 12B. The image signal which is the output of the column ADC block 1211 is read out from the column ADC block 1211 to the horizontal signal line 1215-a or 1215-b by the column scanning circuit 1213-a or 1213-b and output A second reading unit).

Next, an operation of detecting an optimum imaging evaluation value (AF evaluation value) of the AF operation as an example of the imaging evaluation value will be described with reference to Figs. 14A and 14B.

14A is timing for detecting an AF evaluation value (autofocus evaluation value) from an image for evaluation of imaging evaluation, as a result of scene determination to be described later. As shown in Fig. 14A, the imaging timing is defined by the vertical synchronization signal. When the camera is in the AF evaluation mode, the system control unit 1108 raises the AF control signal (to the H level) at the falling edge of the vertical synchronization signal at time T0. Next, when the vertical synchronization signal rises, the system control section 1108 starts and starts the imaging operation for the image display signal and the imaging evaluation value detection signal at the same time in synchronization with the vertical synchronization signal.

In the period T0 to TF1, the imaging evaluation image signal read from the pixel portion 120 via the horizontal signal line 1215-b is input to the imaging evaluation value detection unit 1106. [ Thereafter, AF evaluation values are calculated in the periods TF1 to TF2. The AF evaluation value is calculated according to the timing controlled by the system control section 1108 based on the contrast information and the phase difference information obtained from the image evaluation evaluation value detection image signal output from the image sensor 1102. [ Thereafter, in the periods TF2 to TF3, the imaging evaluation value detection section 1106 outputs the AF evaluation values to the system control section 1108. [

In the example shown in the drawing, one frame of the live view image is picked up and three frames of the AF evaluation value detection image (AF scan) are picked up during the period of one vertical synchronizing signal. When the system control section 1108 changes the vertical synchronizing signal to the L level, the AF evaluation within one frame period of the live view image ends.

The system control unit 1108 compares the AF evaluation value with a predetermined AF expectation value described later. When the AF evaluation value satisfies a predetermined evaluation condition for the AF expectation value, the system control section 1108 lowers the AF control signal (time T1). When the AF control signal falls, only AF evaluation imaging stops, and live view imaging continues.

14B is timing for detecting the AF evaluation value from the live view image in accordance with the result of the scene judgment described later.

As shown in Fig. 14A, the imaging timing is defined by the vertical synchronization signal. If the AF evaluation mode is set, the system control section 1108 raises the AF control signal (to the H level) at the falling edge of the vertical synchronizing signal at time T0. Next, when the vertical synchronization signal rises, the system control section 1108 performs imaging operation only for the image display signal in synchronization with the vertical synchronization signal.

In the periods T0 to TF4, the live view image signal read from the pixel 1201 via 1215-a is input to the evaluation value detection unit 1106 and the image signal processing unit 1103. [ In the periods TF4 to TF5, the AF evaluation value is calculated. The imaging evaluation value detection section 1106 calculates the AF evaluation value in accordance with the timing controlled by the system control section 1108 based on the contrast information and the phase difference information obtained from the image signal of the live view image outputted from the image sensor 1102 do. Thereafter, in the periods TF5 to TF6, the imaging evaluation value detection section 1106 outputs the AF evaluation value to the system control section 1108. [

In the example shown in the drawings, one frame of the live view image is picked up during one vertical synchronizing signal, and the AF evaluation value detection image (AF scan) is not picked up. When the system control section 1108 sets the vertical synchronization signal to the L level, the AF evaluation for one frame period of the live view image is ended.

The system control unit 1108 compares the AF evaluation value detected from the live view image with a predetermined AF expected value described later. When the AF evaluation value satisfies a predetermined evaluation condition for the AF expectation value, the AF control signal is lowered (time T7). When the AF control signal falls, the AF evaluation detection operation based on the display image is stopped and the live view imaging is continued.

As shown in Fig. 14A, in this embodiment, it is possible to set a frame rate faster than the operation of the live view image with respect to the image for evaluation of the image evaluation value. Thus, the reflection of the imaging evaluation value to the imaging apparatus can be controlled faster than before.

However, the imaging apparatus has a tracking limit of dark scenes due to the exposure control set by the program guide. Accordingly, the image for evaluation of image pickup evaluation with a high frame rate and the image for live view with a slow frame rate differ in the follow-up limit of dark scenes due to exposure control. In the present embodiment, a difference of three states occurs in the tracking limit of the dark scene.

The scene discrimination unit 1107 discriminates the characteristic of the shooting scene from the sensitivity set value set as the shooting (exposure) condition or the exposure amount calculated from the shutter speed or the like by the system control unit 1108 at the time of shooting the live view image do. The imaging evaluation value detection unit 1106 detects the imaging evaluation value from either the imaging evaluation value detection image or the live view image in accordance with the discrimination result of the scene discrimination unit 1107. [

Hereinafter, the operation of the imaging apparatus according to the fourth embodiment in the AF evaluation mode will be described in detail with reference to the flowchart of Fig.

At this time, the flowchart shown in the figure is performed under the control of the system control unit 1108. [ For the sake of description, the imaging evaluation value detected in the imaging evaluation value detection image is defined as AF_K alpha, and the imaging evaluation value detected in the live view image is defined as AF_K beta.

After power is turned on by the user and various initial settings are made (step S1502), the camera mode is changed to an operation mode such as live view mode and moving image recording, and shooting starts (step S1520).

The system control unit 1108 determines whether or not the AF evaluation mode is performed (step S1502). In other words, the system control section 1108 determines whether or not the autofocus mode is set. If the AF evaluation mode is not performed (NO in step S1503), the system control unit 1108 starts only live view imaging (step S1520), and proceeds to step S1521 described later.

If the AF evaluation mode is to be executed (YES in step S1503), the system control unit 1108 turns on the AF control signal (H level) (step S1504). Next, the system control section 1108 substitutes 0 into a variable n for counting the number of AF evaluation imaging (step S1505). Next, in step S1506, the system control section 1108 detects the exposure amount S of the imaging condition for performing live view imaging.

Next, the scene determination unit 1107 compares the exposure amount E detected in step S1506 with the exposure amount expected value Ev (imaging condition determination). The system control unit 1108 determines whether or not the exposure amount of the live view photographing satisfies the following equation (1), that is, a predetermined sensitivity condition, with respect to the expected value Ev of the exposure setting (step S1507).

E <Home ... (1)

If the exposure amount EV of the live view satisfies the expression (1) (YES), the process proceeds to the operation in S1508 to start the AF evaluation value detection imaging.

Next, as described in Fig. 14A, the system control section 1108 starts AF evaluation imaging (step S1508). After AF evaluation imaging is started, the system control unit 1108 increments the variable n by 1 (step S1509). Thereafter, under the control of the system control section 1108, the imaging evaluation value detection section 1106 detects the AF evaluation value AF_Kα from the AF evaluation image signal obtained in the AF evaluation imaging (step S1510).

Next, the system control unit 1108 determines whether or not the AF evaluation value AF_Kα satisfies the following equation (2), that is, the predetermined evaluation condition, with respect to the AF expected values K_minα and K_maxα (step S1511).

K_minα <AF_Kα <K_maxα (2)

Here, the AF evaluation value expectation values K_min [alpha] and K_max [alpha] are set as the minimum and maximum values of the expected AF evaluation value. These values are pre-recorded in the system control section 1108 at the time of designing of the image pickup apparatus or adjustment of the image pickup apparatus.

If the AF evaluation value AF_Kα does not satisfy the formula (2) (NO in step S1511), the system control section 1108 calculates the feedback control amount based on the AF evaluation value AF_Kα. Thereafter, the system control unit 1108 controls the lens drive control unit 1105 according to the feedback control amount to drive the focus lens provided in the lens 1101 (step S1512).

Next, the system control section 1108 judges whether or not the variable (the number of times AF evaluation value imaging) n is a predetermined number (3 in this case) (step S1513). If the number of times of AF evaluation value imaging is less than 3 (NO in step S1511), the system control unit 1108 returns to the processing of step S1510 to perform AF evaluation imaging. On the other hand, if the number of times the AF evaluation value imaging is 3 (YES in step S1513), the system control unit 1108 returns to the process of step S1505 and sets the AF evaluation value imaging number n to zero.

If the AF evaluation value AF_Kα satisfies the expression (2) (YES in step S1511), the system control section 1108 turns off the AF control signal (L level) (step S1514) (Step S1515). Thereafter, the system control section 1108 advances the operation to step S1522.

If the exposure amount E of the live view image in step S1507 does not satisfy the expression (1) (NO), the process proceeds to step S1516 to detect the AF evaluation value AF_K? From the live view image. Next, the system control unit 1108 determines whether the AF evaluation value AF_Kβ satisfies the following equation (3), that is, the predetermined evaluation condition, with respect to the AF expected values K_minβ and K_maxβ (step S1517).

K_minβ <AF_K <K_maxβ (3)

Here, the AF expected values K_min [beta] and K_max [beta] are set as the minimum and maximum values of the expected AF evaluation value. These values are pre-recorded in the system control section 1108 at the time of designing of the image pickup apparatus or adjustment of the image pickup apparatus.

If the AF evaluation value AF_Kβ does not satisfy the formula (3) (NO in step S1517), the system control section 1108 calculates the feedback control amount in accordance with the AF evaluation value AF_Kβ. Thereafter, the system control section 1108 controls the lens drive control section 1105 in accordance with the feedback control amount to drive the focus lens provided in the lens 1101 (step S1518), and proceeds to the operation of step S1522.

(YES in step S1517), the system control unit 1108 turns off the AF control signal (L level) (step S1519), and in step S1522, It proceeds. In step S1522, if there is an instruction to end the live view operation (YES), the live view operation ends. If the live view moving image continues (NO), the process returns to step S1503 to perform the AF operation while performing the live view operation.

As described above, the present embodiment is based on an image pickup apparatus having an image pickup device capable of simultaneously performing live view image pickup and image pickup evaluation value detection image pickup in one frame period. An image for detecting the AF evaluation value is selected from the AF evaluation value image and the live view image in accordance with the result of scene determination based on the exposure condition at the time of live view imaging. As a result, it is possible to shorten the time delay in performing AF evaluation at the time of shooting a subject in a bright scene, and improve the accuracy of the AF evaluation value in a dark scene. In the present embodiment, the AF expectation value is compared with the AF evaluation value to set a different AF expectation value for the AF evaluation value image and the live view image. However, these expected values may be the same.

In the present embodiment, the AF evaluation value is described as an example of the imaging evaluation value, but other imaging evaluation values such as the WB evaluation value (white balance data) and the AE evaluation value (exposure control data) The evaluation value is also detected. In the case of the WB evaluation value or the AE evaluation value, the image pickup evaluation value detection image or live view image is switched in order to detect the evaluation value according to the result of the scene discrimination in step S1507. Thus, the time delay can be shortened and the precision of WB or AE evaluation value detection can be optimized.

Fifth Embodiment

In the fourth embodiment of the present invention, a configuration has been described in which the photographic scene is determined based only on the exposure information, and the AF evaluation value is detected from the AF evaluation value image or the live view image in accordance with the determination result. In the present embodiment, the image pickup evaluation value is detected with higher precision by discriminating the image pickup scene even on the basis of the face information, the luminance information and the color information, as well as the exposure information. Hereinafter, an imaging apparatus according to a fifth embodiment of the present invention will be described with reference to Figs. 16 to 18. Fig. At this time, the constituent members shown in the same figure as the fourth embodiment are denoted by the same reference numerals, and a description thereof will be omitted.

16 is a block diagram of an image pickup apparatus according to the present embodiment. This embodiment is the same as the fourth embodiment except that it has a face information detecting section 1601, a luminance information detecting section 1602 and a color information detecting section 1603 in the configuration.

The face information detection unit 1601 performs face detection processing on the image signal output from the image sensor 1102 and detects the face of a person or an animal (for example, a pet) in the photographed frame image. The face information detection unit 1601 also outputs the detected face area to the scene discrimination unit 1107 as face information.

The luminance information detection unit 1602 performs luminance detection processing on the image data image output from the image signal processing unit 1103. [ In the process, the image frame image is divided into a plurality of regions, and an average luminance of each region is obtained. The luminance information detecting unit 1602 calculates luminance information such as a luminance difference and a central luminance value between the central portion of the frame image and the peripheral portion thereof using the average luminance thereof. The luminance information detected by the luminance information detecting unit 1602 is output to the scene determining unit 1107. [

The color information detection unit 1603 performs color detection processing on the image data image output from the image signal processing unit 1103 to detect color information such as an average color and an area of a high color area. The color information detected by the color information detection unit 1603 is output to the scene determination unit 1107. [

The scene discrimination section 1107 judges whether or not the image data image processed in the image signal processing section 1103 based on each piece of information inputted from the face information detection section 1601, the luminance information detection section 1602 and the color information detection section 1603 The background of the shooting scene and the subject of the shooting scene are discriminated. At this time, the pieces of information sent from the face information detection section 1601, the luminance information detection section 1602, and the color information detection section 1603 are temporarily stored by the scene discrimination section 1107 and updated as necessary.

Next, a determination operation of the shooting scene in the imaging apparatus according to the present embodiment will be described.

The scene discrimination section 1107 uses the luminance information detected by the luminance information detection section 1602 and the color information detected by the color information detection section 1603 with respect to the image signal of the live view outputted from the image sensor 1102 , The background of the shooting scene is discriminated. Furthermore, the scene discrimination section 1107 uses the face information detected by the face detection section 1601 to discriminate the subject in the shooting scene.

First, the determination of the background of the shooting scene will be described.

The scene discrimination section 1107 analyzes the luminance information detected by the luminance information detection section 1602 and the color information detected by the color information detection section 1603 and judges whether the area of the blue sky area on the image is equal to or more than a threshold value do. The scene discrimination unit 1107 judges that the background of the shooting scene is a blue sky when the area of the blue sky-blue area is equal to or larger than the threshold value. The scene discrimination section 1107 analyzes luminance information from the luminance information detection section 1602 and color information from the color information detection section 1603. As a result, when the scene discrimination unit 1107 judges that the luminance on the image satisfies the predetermined histogram distribution or distribution condition, it determines that the background of the shooting scene is the night scene. For example, the brightness of an image in a dark scene such as a night scene occupies most of the low-luminance portion, and a state in which a high-luminance portion occurs singly. The scene discrimination unit 1107 analyzes the luminance information from the luminance information detection unit 1602 and the color information from the color information detection unit 1603 and determines whether the areas of the average color and high color areas on the image are all equal to or more than the threshold value Or not. If these values are greater than or equal to the threshold value, the scene discrimination section 1107 judges that the photographic scene is a clear scene.

Next, an operation of determining a subject in the shooting scene will be described.

The scene discrimination section 1107 analyzes the face information from the face detection section 1601. [ When a face is detected from the image signal, the scene discrimination section 1107 judges that the subject in the photographing scene is a person.

The scene discrimination section 1107 judges both the background of the scene and the subject as described above, combines the judgment results thereof, and outputs the combined judgment result to the system control section 1108. [

Next, the detailed operation in the AF evaluation mode of the imaging apparatus according to the present embodiment will be described with reference to the flowchart of Fig. In order to describe the detailed operation of this embodiment, the face information detection value detected from the live view image is defined as X1, the luminance information detection value as Y1, and the color information detection value as Z1. Only the operation phases different from those of the fourth embodiment will be described.

The scene discrimination section 1107 judges whether or not the expected value corresponding to the detected value of each detected information: face information X; Luminance information Y; And the color information Z, and selects the AF evaluation value AF_K alpha or AF_K beta as shown in FIG. In accordance with the selection result, the branching in step S1702 is determined.

In step S1701, the face information detection unit 1601, the luminance information detection unit 1602, and the color information detection unit 1603 detect face information X1, luminance information Y1, and color information Z1 from the acquired live view image. In step S1702, as shown in the table of Fig. 18, from the respective information values detected by the image determination evaluation value image and the live view image in step S1701 by the scene determination unit 1107, the image evaluation &Lt; / RTI &gt;

For example, in one example, it is assumed that the relationship of each information value is as follows:

Face information value: X1> X

Luminance information value: Y1 > Y

Color information value: Z1> Z

In this case, in step S1702, the AF evaluation value detection imaging is started (that is, branching to YES), the operation proceeds to step S1508, and the system control unit 1108 increments the variable n by 1 (step S1509). The subsequent processing is the same as in the fourth embodiment.

In another example, the relationship of each information value is as follows:

Face information value: X1? X

Luminance information value: Y1? Y

Color information value: Z1? Z

In this case, in step S1702, the AF evaluation value detection imaging is not started (that is, branching to NO), and the process proceeds to step S1516 to detect the AF evaluation value AF_Kβ from the live view imaging image. The subsequent processing is the same as in the fourth embodiment. In the case of other scene discrimination, the relationship shown in FIG. 18 is used.

As described above, the present embodiment is based on an image pickup device having an image pickup device capable of simultaneously performing live view image pickup and image pickup evaluation value detection image pickup in one frame period. An image for detecting the AF evaluation value is selected from the image for AF evaluation value or the image for live view in accordance with the determination result of the shooting scene based on the brightness / color / face information. Therefore, when shooting a subject in a bright scene, the time delay in performing the AF evaluation can be shortened, and in the dark scene, the accuracy of the AF evaluation value can be improved.

In the present embodiment, when the scene is discriminated, face information, luminance information, and color information are detected from each of the image pickup evaluation value detection image and the live view image. However, the present invention is not limited to this configuration. When the sensitivity described in the first embodiment is detected and the result is also used as one factor of the scene discrimination, the time delay in detecting the AF evaluation value can be further shortened, Further optimization is possible.

In the present embodiment, imaging evaluation values are determined from captured images when at least two of face information, luminance information, and color information, which is information necessary for scene determination, are large information values. However, the present invention is not limited to this. The comparison may be performed by weighting each information value according to the imaging evaluation value.

Sixth Embodiment

Now, a sixth embodiment of the present invention will be described. The present embodiment is configured to form the imaging evaluation value detection section 1106 in the pixel drive section of the inside of the image sensor 1102, for example, the pixel section of the second chip 121 in Fig. 12A.

19 is a block diagram of an image sensor 1102 incorporating an imaging evaluation value detection unit. In Fig. 19, the constituent members as shown in Figs. 12A and 12B are denoted by the same reference numerals.

In the figure, the imaging evaluation value detection section 1901 detects an imaging evaluation value, such as an AF evaluation value (autofocus data), and outputs only the detected evaluation value to the system control section 1106. [ The imaging evaluation value detection section 1901 operates in accordance with the timing controlled by the system control section 1108 based on the contrast information and the phase difference information obtained from the image signal obtained by the imaging element 1102. [

The switches 1902 and 1903 are controlled by the system control unit 1108. The switches 1902 and 1903 switch the image signal for image pickup evaluation value detection and the image signal for live view on the basis of the discrimination result of the scene discrimination section 1107 so that one of the signals detects the image pickup evaluation value And is selectively inputted to the imaging evaluation value detection unit 1901. [ The switch 1902 selects an output destination of signals of pixels corresponding to the imaging evaluation values shown in FIG. 13, and the output destination at this time is one of the signal processing section 1103 and the imaging evaluation value detecting section 1901. The switch 1903 is a switch that is turned on when the signals of pixels corresponding to the selected row for live view shown in Fig. 13 are used for the imaging evaluation value.

The operation of the image sensor of Fig. 19 will be described with reference to the flowchart of Fig. 15 when it is used in the image pickup apparatus according to the fourth embodiment.

In step S1503, the AF operation is started. As described in the fourth embodiment, when the exposure amount Ev of the live view satisfies the expression (1) (YES) in the step S1507, the process proceeds to the operation in the step S1508 and the imaging for AF evaluation value detection is started . At this time, the switch 1902 is connected to the imaging evaluation value detector 1901 side, and the switch 1903 is turned off.

After AF evaluation imaging is started, the system control unit 1108 increments the variable n by 1 (step S1509). Thereafter, the imaging evaluation value detection section 1901 detects the AF evaluation value AF_Kα from the AF evaluation value image.

In step S1507, if the exposure amount Ev of the live view does not satisfy the expression (1) (NO), the operation proceeds to step S1516. In step S1516, the switch 1903 is turned on, and the imaging evaluation value detection unit 1901 detects the AF evaluation value AF_K? From the live view image signal. At this time, although the switch 1902 is connected to the signal processing unit 1103 side, the pixel signal to the signal processing unit is not outputted because the operation for the AF evaluation value is not performed. Further, since the imaging evaluation value detecting section 1901 transmits only the AF evaluation value to the system control section 1108, the amount of data to be transferred to the outside can be reduced as compared with the fourth embodiment, and the power consumption can be reduced . Since the subsequent operations are the same as those in the first embodiment, a description thereof will be omitted. At this time, when the image sensor of Fig. 19 is used in the image pickup apparatus according to the fifth embodiment, the same operation is applied.

In the sixth embodiment described above, the imaging evaluation value detecting section is formed in the image sensor, so that the amount of data transmission at the time of detecting the imaging evaluation value in the first and second embodiments can be reduced. Therefore, the power consumption can be reduced.

Other Embodiments

Embodiments of the present invention may also be practiced with other computer-readable media including computer-readable instructions stored on a storage medium (e.g., non-volatile computer readable storage medium) For example, by reading and executing the computer-executable instructions from the storage medium to perform one or more functions of the embodiment (s) to perform the functions of the system or device &lt; RTI ID = 0.0 &gt;Lt; RTI ID = 0.0 &gt; computer. &Lt; / RTI &gt; The computer may have one or more of a central processing unit (CPU), a micro processing unit (MPU), or other circuitry, or may comprise a separate computer or a network of separate computer processors. The computer-executable instructions may be provided to the computer from, for example, a network or the storage medium. The storage medium may be, for example, a hard disk, a random access memory (RAM), a read only memory (ROM), a storage of a distributed computing system, an optical disk (compact disk (CD), digital versatile disk Disk (BD) ^TM, etc.), a flash memory device, a memory card, and the like.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be construed broadly to include structures and functions equivalent to all variations.

Claims (15)

An imaging device comprising an optical system for imaging an optical image to form an optical image of a subject and generate an image signal,
And second element means including first element means having a pixel portion including a plurality of pixels arranged in a matrix form and reading means for reading the optical image from the pixel portion, Wherein the reading means comprises first reading means for reading the image signal from the first pixel group of the pixel portion and second reading means for reading the image signal from the second pixel group of the pixel portion, An imaging device including second reading means for reading a signal;
Imaging condition determining means for obtaining information about the imaging condition of the optical image from the image signal output from the imaging device and determining the imaging condition using the acquired information; And
An imaging evaluation value for detecting an imaging evaluation value related to the imaging of the optical image based on a result of the determination by the imaging condition determining means from one of the image signals read by the first reading means and the second reading means And an image pickup device.
The method according to claim 1,
Wherein the information regarding the imaging condition is an exposure amount for imaging the optical image,
Wherein the imaging condition determining means is arranged to compare the exposure amount with a predetermined exposure amount for determining the imaging condition.
The method according to claim 1,
Wherein the image pickup condition determining means comprises a brightness degree detecting means for detecting brightness information of the image signal outputted from the image pickup element, a color information detecting means for detecting color information of the image signal outputted from the image pickup element, And face information detecting means for detecting face information of the person picked up based on the image signal outputted from the image pickup element,
Wherein the imaging condition determining means is arranged to make the determination of the imaging condition based on the brightness information, the color information, and the face information.
The method according to claim 1,
Further comprising control means for controlling said reading means,
Wherein the control means is arranged to drive at least one of the first reading means and the second reading means at a predetermined frame rate based on the determined imaging condition.
5. The method of claim 4,
Wherein the frame rate of the pixel signal read from the second pixel group is smaller than the frame rate of the pixel signal read from the first pixel group.
The method according to claim 1,
Wherein the imaging evaluation value detection means is arranged to detect at least one of autofocus data, exposure control data and white balance data.
5. The method of claim 4,
Wherein the control means is arranged to control the driving of the optical system in accordance with the imaging evaluation value detected by the imaging evaluation value detection means.
5. The method of claim 4,
Wherein the control means is arranged to control the exposure of the optical system in accordance with the imaging evaluation value detected by the imaging evaluation value detection means.
5. The method of claim 4,
Wherein the control means is arranged to control the white balance of the image signal in accordance with the imaging evaluation value detected by the imaging evaluation value detection means.
The method according to any one of claims 4, 5, 7, 8, and 9,
The imaging evaluation value detection means is provided to the second element means,
The second element means includes a switch for selectively inputting the image signal read out from the first reading means and the second reading means to the imaging evaluation value detection means and the conversion means for converting the image signal into a digital signal Further comprising:
11. The method of claim 10,
And the control means is arranged to control the switch in accordance with the determined imaging condition.
The method according to claim 1,
Wherein the first pixel group and the second pixel group include a plurality of pixels in different rows of the pixel portion.
The method according to claim 1,
Wherein the first element means and the second element means are laminated, and the first element means is positioned on a side that receives the optical image.
An optical system for forming an optical image of a subject and an imaging device for imaging the optical image to generate an image signal, the imaging device comprising: a first element unit having a pixel section including a plurality of pixels arranged in a matrix shape; And second reading means for reading the optical image from the pixel portion, wherein the plurality of pixels are arranged to photoelectrically convert the optical image to generate an image signal, and the reading Means for reading out the image signal from the first pixel group of the pixel portion and second reading means for reading the image signal from the second pixel group of the pixel portion,
Acquiring information on the imaging condition of the optical image from the image signal output from the imaging element and determining the imaging condition using the acquired information; And
And detecting an imaging evaluation value related to the imaging of the optical image based on the determined imaging condition from one of the image signals read by the first reading means and the second reading means.
A computer-readable storage medium storing a program for controlling an imaging apparatus such that a computer executes a control method according to claim 14.

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