JP2002185868A - Imaging device, and electronic camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging device that can obtain image data under different exposure conditions in a short photographing required time through image pickup. SOLUTION: The imaging device is configured with light receiving pixels that are arranged on a light-receiving face and store pixel outputs in response to an incident light, a storage control section that revises the storage time of the light-receiving pixels in the unit of pixels and/or in the unit of lines so as to generate pixel outputs different from storage times so as to be nearly uniformly distributed on the light receiving face and an image generating section that classifies pixel outputs generated by the storage control section by each kind of the storage time so as to generate image data with different storage times.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image pickup apparatus for picking up an optical image and generating image data. The present invention relates to an electronic camera provided with the imaging device.

[0002]

2. Description of the Related Art Conventionally, automatic bracketing has been known as a photographing method of an electronic camera. In this auto bracketing, the electronic camera performs continuous shooting while automatically shifting exposure conditions. On the user side,
From the image data of a plurality of frames shot continuously in this way,
Image data under the optimal exposure condition can be selected.

[0003]

However, in the conventional auto bracketing, the subject is photographed a plurality of times. Therefore, the time required for shooting is several times longer than that of normal shooting. In particular, in hand-held shooting, the user must maintain the shooting attitude of the camera during that time, and there is a problem that the usability is poor.

Further, in the conventional auto bracketing, since the photographing operation is sequentially repeated, the shutter timing is clearly different for each photographed frame. For this reason, it is very difficult to obtain image data that satisfies both the photo opportunity and the exposure condition when aiming for a momentary photo opportunity as in the case of photographing a person. Furthermore, the conventional auto bracketing requires storing a plurality of image data at once, and consumes a large amount of storage capacity. Therefore, there is a problem that the auto bracketing cannot be executed unless the buffer memory or the card medium of the electronic camera has a sufficient margin.

Further, in the conventional auto bracketing, in order to request the user to select image data,
A plurality of image data must be displayed on a monitor. In this case, the electronic camera changes the “resolution of the image sensor” to the “display resolution of the monitor” for all of the plurality of image data.
Resolution conversion must be performed sequentially. Therefore, there is a problem that it takes time to complete the monitor display, and the usability is deteriorated.

Further, in the conventional auto bracketing, it is necessary to sequentially perform image processing on all of a plurality of image data at "resolution of an image sensor". For this reason, there has been a problem that it takes time to perform image processing, and the usability deteriorates. Therefore, an object of the present invention is to photograph a plurality of image data having different exposure conditions in a short photographing time.

It is another object of the present invention to photograph a plurality of image data having different exposure conditions at substantially the same shutter timing. Another object of the present invention is to
An object of the present invention is to enable a plurality of image data having different exposure conditions to be photographed with a small storage capacity. It is another object of the present invention to enable a plurality of image data having different exposure conditions to be displayed on a monitor in a short processing time. Another object of the present invention is to convert a plurality of image data with different exposure conditions into
It is to enable image processing in a short processing time.

[0008]

Means for Solving the Problems To solve the above-mentioned problems, the invention described in each claim is configured as follows. Here, the expression “A and / or B” means “one of a group consisting of“ A ”,“ B ”, and“ A and B ””.

(1) An image pickup apparatus according to (1), wherein a plurality of light receiving pixels arranged on a light receiving surface and accumulating a pixel output according to incident light, and an accumulation time of the light receiving pixels are set in pixel units and / or Or, a storage control unit that generates pixel outputs having different accumulation times by changing the line units so as to be substantially uniformly distributed on the light receiving surface, and classifies the pixel outputs generated by the accumulation control unit for each type of accumulation time, An image generation unit that generates a plurality of image data having different accumulation times.

(2) In the imaging device according to the second aspect, in the imaging device according to the first aspect, the accumulation control unit may set the accumulation time in pixel units and / or within the same exposure period of the light receiving pixels. By changing the output in units of lines, pixel outputs having different accumulation times are generated so as to be substantially evenly distributed on the light receiving surface.

<Claim 3> In the imaging device according to the third aspect, in the imaging device according to the first or second aspect, the accumulation control unit determines a timing of discharging the invalid charge from the light receiving pixels on a pixel-by-pixel basis. And / or by changing each line, pixel outputs having different accumulation times are generated so as to be substantially uniformly distributed on the light receiving surface.

<Fourth aspect> In the imaging device according to the fourth aspect, in the imaging device according to the first or second aspect, the accumulation control unit determines a timing at which a pixel output is read from the light receiving pixel in units of a pixel and / or a pixel. Alternatively, the pixel outputs having different accumulation times are generated so as to be substantially uniformly distributed on the light receiving surface by changing the pixel output in line units.

A fifth aspect of the present invention provides an electronic camera including the imaging device according to any one of the first to fourth aspects, and a control unit that controls an imaging operation of the imaging device. The control unit controls the imaging device to generate a plurality of image data having different storage times as an operation mode that can be selected, and the control unit controls the imaging device to capture one type of image data having the storage time. And a normal shooting mode.

<Sixth Embodiment> The electronic camera according to the sixth aspect is the electronic camera according to the fifth aspect, in which a plurality of image data captured in the auto bracketing mode are displayed for comparison, and an image selection operation by a user is performed. And an input unit for receiving the image data selected by the input unit.

<Seventh aspect> The electronic camera according to the seventh aspect, in the electronic camera according to the fifth aspect, displays a plurality of image data captured in the auto bracketing mode in a contrasting manner, and performs an image selection operation by a user. The control unit executes the normal shooting mode by setting the storage time of the image data selected by the input unit.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

<< First Embodiment >> A first embodiment is an embodiment of an electronic camera according to claims 1, 2, 4 to 7.

[Configuration of First Embodiment] FIG. 1 is a block diagram showing the configuration of an electronic camera 11. In FIG. 1, a photographing lens 12 is mounted on an electronic camera 11. The light receiving surface of the image sensor 13 is arranged in the image space of the taking lens 12. The image output of the image sensor 13 is
The signal is output to the bus 16 via the A / D converter 14 and the image processor 15. The image pickup device 13a is configured by the image pickup device 13, the A / D conversion unit 14, and the image processing unit 15.
Is configured.

An MPU (Micro Processor Unit) 17 for system control, an image memory 18 for temporarily storing image data, an image display circuit 20 for displaying an image on a monitor 19, and a compression recording of the image data The compression recording sections 21 are connected by signals. This MPU
An operation unit including a release button, a mode setting button, and the like is signal-connected to 17. Further, the MPU 17 includes the imaging device 1
3 and a control signal to the image processing unit 15.

FIG. 2 is a diagram showing the internal configuration of the image pickup device 13. Hereinafter, the internal configuration of the image sensor 13 will be described with reference to FIG. First, unit pixels 1 are arranged in a matrix of n rows and m columns on the light receiving surface 1a of the image sensor 13. Each of these unit pixels 1 includes a photodiode PD that performs photoelectric conversion, a charge discharging MOS switch QP, a row reading MOS switch QX, and an amplifying element QA.

The outputs of the unit pixels 1 are commonly connected for each vertical column to form m vertical read lines 2. A current source 4 is connected to each of the vertical read lines 2. Further, the image sensor 13 is provided with the vertical scanning circuit 3. The vertical scanning circuit 3 includes a row-reading control pulse Grd and a charge discharging control pulse G
rs is output line by line. This control pulse Grd is M
It is provided to the gate of OS switch QX. The control pulse Grs is given to the gate of the MOS switch QP.

Further, these vertical read lines 2 are connected to a horizontal read line 7 via a read circuit 5 and a MOS switch QH. The gates of the MOS switches QH are supplied with horizontal read control pulses φH1 to φH1 from the horizontal scanning circuit 8, respectively.
The horizontal read line 7 is connected to a reset MOS switch QRSH. These MOS switches Q
RSH includes a control pulse φRSH for reset at a timing synchronized with the control pulses φH1 to φH for horizontal reading.
Is supplied.

[Correspondence between First Embodiment and Items in Claims] The correspondence between the above-described configuration and the invention will be described below. Note that the correspondence described here is an interpretation for reference, and does not limit the invention. Regarding the correspondence between the first, second, and fourth aspects and the embodiment, the light receiving pixels correspond to the photodiodes PD,
The accumulation control unit corresponds to the vertical scanning circuit 3, and the image generation unit corresponds to the horizontal scanning circuit 8 and the image processing unit 15. Regarding the correspondence between claim 5 and the embodiment, the imaging device corresponds to the imaging element 13, the A / D conversion unit 14 and the image processing unit 15, and the control unit corresponds to the MPU 17. Regarding the correspondence between claim 6 and the embodiment, the input unit corresponds to the operation unit 22, the image display circuit 20 and the monitor 19, and the selection storage unit corresponds to the compression recording unit 21. Regarding the correspondence between claim 7 and the embodiment, the input unit corresponds to the operation unit 22, the image display circuit 20 and the monitor 19, and the control unit is the MPU 17.
Corresponding to

[Explanation of Operation of First Embodiment] FIG. 3 is a flowchart for explaining the operation of the electronic camera 11. FIG.
FIG. 9 is an explanatory diagram illustrating an operation of the imaging device 13a in a normal shooting mode. FIG. 5 is an explanatory diagram illustrating the operation of the imaging device 13a in the auto bracketing mode. Hereinafter, in accordance with the step numbers shown in FIG.
Will be described.

Step S1: When the main power supply of the electronic camera 11 is turned on, the MPU 17 performs predetermined initial settings and waits for a release operation by the user. Here, when a release operation is detected via the operation unit 22,
The MPU 17 starts the photographing operation in step S2.
Move the operation to.

Step S2: The MPU 17 first determines the operation mode of the electronic camera 11. Electronic camera 11
Is set to the “normal shooting mode”, the MPU1
7 shifts the operation to step S3. On the other hand, if "Auto bracketing mode" is set, MP
U17 shifts the operation to step S10.

Step S3: The MPU 17 performs a known exposure calculation based on the luminance of the object obtained from a photometric device (not shown), and automatically determines the accumulation time (corresponding to the shutter speed) of the image sensor 13. The storage time thus determined is set in a register in the MPU 17.

Step S4: "Black square" shown in FIG.
Indicates the timing of discharging the invalid charges in the normal photographing. The vertical scanning circuit 3 in the image sensor 13 sequentially outputs the control pulse Grs to each row according to the ejection timing. As a result, the MOS switches QP in each row are sequentially turned on, and the invalid charges are sequentially discharged.

Step S5: The MPU 17 waits for the accumulation time to elapse, starting from the start of the discharge of the invalid charges.
When the accumulation time has elapsed, the operation moves to step S6.

Step S6: "Square with hatching" shown in FIG. 4 indicates the read timing of the pixel output. The vertical scanning circuit 3 in the image sensor 13 sequentially outputs a control pulse Grd to each row according to the readout timing. As a result, the MOS switches QX of each row
Are sequentially turned on, and the sources of the amplifier elements QA are sequentially connected to the vertical read line 2. As a result, pixel outputs buffer-amplified by the amplification element QA are sequentially output to the vertical read line 2 in row line units. During the output period for one row, the horizontal scanning circuit 8 sequentially outputs control pulses φH1 to φH1 to m. As a result, the MOS switches QH are sequentially turned on, and the pixel outputs for one row are serially output to the horizontal read line 7. With such an operation,
Image data for one screen is read from the image sensor 13.

Step S7: The image data for one screen is digitized via the A / D converter 14, and
The image processing section 15 performs image processing such as gamma correction. The image processing unit 15 temporarily stores the image data after the image processing in the image memory 18.

Step S8: The compression recording section 21 compresses and encodes one screen of image data in the image memory 18,
Record on a recording medium such as a memory card. The operation in the normal shooting mode is completed by the operation up to this point.

Step S10: On the other hand, if the auto bracketing mode has been selected, the MPU 17
Based on the exposure setting of the auto bracketing, an operation schedule as shown in FIG. 5 is created according to the following procedure. First, as shown in FIG. 5, the MPU 17 arranges the discharge timings (black squares) of each row in the order of the rows. Next, the MPU 17 sets the number P of frames for auto bracketing and the shortest accumulation time T based on user settings and the like. From this setting, the MPU 17 calculates P types of accumulation times T, 2T, 4T,..., 2 ^(P-1) T. Subsequently, the MPU 17 arranges the P types of accumulation times sequentially starting from the discharge timing of each row, and determines the read timing (hatched square) of each row as shown in FIG. At this time, if the read timings of a plurality of rows overlap at the same time, the read timing with the longer accumulation time is shifted back and forth to avoid duplication. M
The PU 17 transfers the operation schedule created in this way to the vertical scanning circuit 3 and the image processing unit 15. The vertical scanning circuit 3 and the image processing unit 15 respectively store the operation schedule.

Step S11: The vertical scanning circuit 3 sequentially refers to the operation schedule while advancing the time according to the clock of the vertical scanning. As a result of this reference, when there is a row corresponding to the ejection timing, the vertical scanning circuit 3
A control pulse Grs for discharging electric charges is output to the corresponding row. When a row corresponding to the read timing exists, the vertical scanning circuit 3 outputs a control pulse Grd for reading to the row. By such timing control, on the light receiving surface 1a, the pixel outputs of each row generated by the P types of accumulation times are generated so as to be substantially evenly distributed. The pixel outputs of these rows are arranged in the vertical read line 2 in the order of the output of the read control pulse Grd.
Are sequentially output. In parallel with this vertical read operation,
During the output period of the pixel output for one row, the horizontal scanning circuit 8
Control pulses φH1 to φH1 to m are output every P columns. As a result, the pixel outputs for one row are thinned out every P columns and serially output to the horizontal read line 7.

Step S12: The image data serially output as described above is digitized via the A / D converter 14, and then supplied to the image processor 15. The image processing unit 15 classifies the image data for each type of accumulation time while referring to the operation schedule. The image processing unit 15 rearranges the classified pixel outputs in the order of rows and arranges them in the image memory 18 to generate P types of “image data having different accumulation times”.

Step S13: The image display circuit 20
Monitor 19 types of “image data with different accumulation times”
Is converted in accordance with the display resolution of the monitor, and the thumbnail is displayed on the monitor 19.

Step S14: The user operates the operation unit 2
2 is operated to select image data with proper exposure (hereinafter referred to as “selected image”) from the thumbnail display.

Step S15: The MPU 17 determines whether or not to record the selected image based on a user setting or the like. Here, when recording the selected image, the MPU 17
Shifts the operation to Step S16. On the other hand, when the selected image is not recorded, the MPU 17 shifts the operation to Step S17.

Step S16: The MPU 17 instructs the compression recording section 21 to compress and record the selected image. The compression recording unit 21 performs compression encoding on the selected image and records the selected image on a recording medium such as a memory card. With the above operations, the operation in the auto bracketing mode is completed.

Step S17: On the other hand, when the selected image is not recorded, the MPU 17 obtains the accumulation time of the selected image and sets it as the accumulation time of the normal photographing mode.

Step S18: The MPU 17 waits for a release operation by the user. When the release operation is performed, the MPU 17 shifts the operation to Step S4,
The normal shooting mode is executed according to the accumulation time of the selected image. With this operation, an automatic transition from the auto bracketing mode to the normal shooting mode is performed.

[Effects of First Embodiment, etc.] According to the above-described operation, in the first embodiment, P types of "image data having different accumulation times" can be obtained by a single photographing operation. Therefore, the required photographing time can be remarkably reduced as compared with the conventional auto bracketing.
Further, in the first embodiment, P types of image data are
Images are taken at approximately the same shutter timing. Therefore, the user only has to perform the release operation by giving priority to the photo opportunity, and can select image data with more appropriate exposure conditions from image data having substantially the same photo opportunity. As a result, it is possible to easily obtain image data satisfying both the photo opportunity and the exposure condition.

In the first embodiment, each of P types of image data is created by distributing image data for one screen. Therefore, no matter how much the number of frames P for auto bracketing is increased, there is no possibility that the capacity of the image memory 18 will be excessive. Further, in the first embodiment, since the number of pixels of the image data is small, the resolution conversion for monitor display can be executed with a small amount of arithmetic processing.

In the first embodiment, the timing of discharging the invalid charges is common to the normal shooting mode and the auto bracketing mode (see FIGS. 4 and 5). Therefore, it is not necessary to change the operation of the “output circuit portion of the control pulse Grs” in the vertical scanning circuit 3 in the normal shooting mode / auto bracketing mode. Therefore,
To that extent, the circuit configuration of the vertical scanning circuit 3 can be simplified.

Further, in the first embodiment, the selected image can be stored. In this case, there is no need to redo shooting, and a light shooting operation is realized.

In the first embodiment, it is also possible to set the accumulation time of the selected image and execute normal photographing.
In this case, high-resolution image data can be obtained with proper exposure. Next, another embodiment will be described.

<< Second Embodiment >> A second embodiment is an embodiment of an electronic camera according to claims 1 to 3 and 5 to 7. A feature of the second embodiment is that an operation schedule as shown in FIG. 6 is used. The other points are the same as in the first embodiment (FIGS. 1, 2 and 3). Therefore, here, the reference numerals of FIGS. 1 and 2 are used as they are, and redundant description is omitted.

The procedure for creating an operation schedule according to the second embodiment will be described below. First, MPU17
Arranges the read timings (hatched squares) of each row in the order of the rows, as shown in FIG. Next, M
The PU 17 sets the number P of frames for auto bracketing and the shortest accumulation time T based on user settings and the like. From this setting, the MPU 17 calculates P types of accumulation times T, 2T, 4T,..., 2 ^(P-1) T. Subsequently, the MPU 17 arranges P kinds of accumulation times in order with the read timing of each row as an end point, and determines the discharge timing (black square) of each row as shown in FIG. According to the operation schedule set in this way, the electronic camera 11 executes the operation in the auto bracketing mode.

[Effects of Second Embodiment, etc.] In the second embodiment, the same effects as in the first embodiment can be obtained except for the difference in the operation schedule. Further, the effects specific to the second embodiment are as follows. The read timing of a plurality of rows is never set at the same time. Therefore, it is possible to reliably avoid a problem that the pixel outputs of a plurality of rows collide on the vertical readout line 2. Pixel output is read out in the order of the rows. Therefore, it is not necessary to rearrange the image data according to the order of the rows after reading the image data. The pixel output readout operation is common between the normal shooting mode and the auto bracketing mode. Therefore, it is not necessary to change the operation of the “control pulse Grd output circuit portion” in the vertical scanning circuit 3 in the normal shooting mode / auto bracketing mode. Therefore, the circuit configuration of the vertical scanning circuit 3 can be simplified accordingly. Next, another embodiment will be described.

Third Embodiment A third embodiment is an embodiment of an electronic camera according to claims 1 to 7. Third
The feature of this embodiment is that an operation schedule as shown in FIG. 7 is used. For other points,
This is the same as the first embodiment (FIGS. 1, 2 and 3). Therefore, here, the reference numerals of FIGS. 1 and 2 are used as they are, and redundant description is omitted.

The procedure for creating an operation schedule according to the third embodiment will be described below. First, MPU17
Arranges the intermediate timing of the accumulation time in each row (dotted line in FIG. 7) in the order of the rows as shown in FIG. Next, the MPU 17 sets the number P of frames for auto bracketing and the shortest accumulation time T based on user settings and the like. From this setting, the MPU 17 calculates P types of accumulation times T, 2T, 4T,..., 2 ^(P-1) T. Subsequently, the MPU 17 arranges P types of accumulation times in order with the intermediate timing of each row as an intermediate point, and as shown in FIG. 7, sets the discharge timing (black square) and readout timing (hatched square) of each row. Determine. According to the operation schedule set in this way, the electronic camera 11 executes the operation in the auto bracketing mode.

[Effects of Third Embodiment] In the third embodiment, the same effects as in the first embodiment can be obtained except for the difference in the operation schedule. Further, as an effect unique to the third embodiment, by aligning the intermediate timing of the accumulation time (dotted line in FIG. 7),
The point is that the shutter timings of the P types of image data exactly match. Next, another embodiment will be described.

<< Fourth Embodiment >> The fourth embodiment is an embodiment of an electronic camera according to claims 1, 2, 4 to 7. The feature of the fourth embodiment is that a CCD type imaging device is used. For other points,
This is the same as the first embodiment (FIGS. 1 and 3). Therefore, here, the reference numerals of FIG. 1 are used as they are, and the duplicate description is omitted.

FIG. 8 is a diagram showing the configuration of an imaging device 30 according to the fourth embodiment. In FIG. 8, a plurality of light receiving elements 31 are arranged on a light receiving surface. This light receiving element 3
The vertical CCDs 32 are arranged in one column unit. Gates 33 are provided between the light receiving element 31 and the vertical CCD 32, respectively. A control pulse is applied to these gates 33 from a vertical scanning circuit 34. In addition, vertical CCD3
The control pulse is also applied to the second transfer electrode from the vertical scanning circuit 34. The transfer electrode of the vertical CCD 32 may be extended to serve as a control electrode of the gate 33. Further, a horizontal CCD 35 is arranged so as to be connected to the output terminal of the vertical CCD 32. The output end of the horizontal CCD 35 is connected to an image distribution unit 36 via an output amplifier.

[Explanation of Operation of Fourth Embodiment] FIGS. 9 to 1
FIG. 3 is a diagram illustrating the operation of the imaging device 30 in the auto bracketing mode. The operation will be described below with reference to these drawings. First, as shown in FIG. 9, the vertical scanning circuit 34 simultaneously opens the gates 33 and
One invalid charge is collectively transferred to the vertical CCD 32. The transferred invalid charges are the vertical CCD 32 and the horizontal CCD 3
5 to the outside. The charge accumulation of the light receiving element 31 is started from the transfer of the invalid charge.

When a predetermined accumulation time T1 has elapsed from the time of the transfer, the vertical scanning circuit 34, as shown in FIG.
Rows are selected at regular row intervals starting from the first row, and the gates 33 of the selected rows are simultaneously opened. As a result, the pixel output of the accumulation time T1 is output at every fixed row interval to the vertical CCD 3
Transferred to 2. Further, when the predetermined accumulation time T2 has elapsed, the vertical scanning circuit 34 selects rows at regular row intervals starting from the second row, as shown in FIG. 11, and simultaneously operates the gates 33 of the selected rows. To open. As a result, the accumulation time T
The two pixel outputs are transferred to the vertical CCD 32 at regular row intervals.

Next, when a predetermined accumulation time T3 elapses,
As shown in FIG. 12, the vertical scanning circuit 34 selects a row at regular row intervals starting from the third row, and simultaneously opens the gates 33 of the selected row. As a result, the pixel output for the accumulation time T3 is transferred to the vertical CCD 32 at regular intervals. By repeating such an operation, pixel outputs having different accumulation times are generated on the light receiving surface so as to be substantially uniformly distributed.

In this state, the vertical scanning circuit 34
A multi-phase control pulse is applied to the transfer electrode of the CD 32.
As a result, as shown in FIG. 13, a pixel output is output from the output end of the vertical CCD 32 in units of rows. Horizontal CCD
35 sequentially and horizontally transfers the pixel outputs in row units.
The pixel output serially output from the horizontal CCD 35 is supplied to an image distribution unit 36 via an output amplifier. The image distribution unit 36 distributes and outputs the pixel output for each type of accumulation time, and generates a plurality of types of “image data having different accumulation times”.

[Effects of Fourth Embodiment] In the fourth embodiment, the same effects as those of the first embodiment can be obtained except for the difference in the image pickup apparatus.

<< Supplementary Items of the Embodiment >> In the above-described embodiment, the case where the accumulation time is changed for each row line has been described. However, the present invention is not limited to this. For example, the accumulation time may be changed in units of column lines or diagonal lines. Further, the accumulation time may be changed not only for each line but also for each pixel. Further, the accumulation time may be changed in a unit of a more complicated pixel pattern by combining a pixel unit and a line unit.

In the above-described embodiment, the case where the mechanical shutter is not used is described. However, the present invention is not limited to this. The exposure period of the imaging device may be limited by opening and closing the mechanical shutter. Alternatively, the start point or the end point of the accumulation time may be limited by opening and closing the mechanical shutter.

In the above-described embodiment, the number of frames for auto bracketing is specified on the drawing because it is specifically illustrated. The present invention is, of course, not limited to this number of frames.

Further, in the above-described embodiment, the aliasing noise of the high spatial frequency component accompanying the thinning-out reading is not described, but it is preferable to take measures against the aliasing noise by image processing or the like.

Further, in the first to third embodiments, the vertical scanning circuit 3 determines the read timing and / or the discharge timing while referring to the operation schedule. In this case, there is an advantage that the number of frames and the exposure setting of the auto bracketing can be flexibly changed. There is also an advantage that the vertical scanning circuit 3 can be realized with a simple circuit configuration including a memory and a memory reading circuit.
However, the present invention is not limited to this. For example, the vertical scanning circuit 3 can be configured by combining a shift register and a logic circuit.

In the first to third embodiments, even when the pixel output is read from the unit pixel 1, the pixel output held by the unit pixel 1 is not destroyed. Therefore, the same unit pixel 1
By reading the pixel output several times from
Pixel outputs of a plurality of types of accumulation times may be generated at the same pixel position.

Further, in the first to third embodiments, each accumulation time of the auto bracketing is determined by the rule of the geometric progression of the ratio “2”, but the present invention is not limited to this. Absent. For example, the accumulation time may be determined by a geometric progression rule of the ratio “square root of 2”. Further, the accumulation time may be determined by a geometric progression rule of the ratio “cubic root of 2”. Further, the accumulation time may be arbitrarily determined. It should be noted that these accumulation times are expected to have a fractional part when allocating read timing and the like. In that case, within the error range of the accumulation time allowed for the imaging device,
The fraction may be rounded down.

In the first embodiment, when the read timings of a plurality of rows overlap at the same time, the read timing with the longer accumulation time is shifted back and forth.
By shifting the readout timing of the longer storage time, there is an advantage that the error of the storage time can be reduced as much as possible. However, the present invention is not limited to this. For example, in the case of determining P types of accumulation times by the geometric progression rule of the ratio “2”, the shortest accumulation time T is set to a multiple of P (however, the radix of the multiple is “time interval between consecutive read timings”). Just set it. With such a setting, in the first embodiment, it is possible to completely avoid duplication of read timing. Further, for example, when the read timings of a plurality of rows overlap, it is possible to read the plurality of rows in a time-division manner using a high-speed clock. In this case, there is an advantage that there is no need to shift the read timing, and an error in the accumulation time can be eliminated.

In the fourth embodiment, the accumulation time is controlled by changing the readout timing in the CCD type imaging device. However, the present invention is not limited to this. For example, even in a CCD type imaging device, the discharge time may be changed in line units and / or pixel units to control the accumulation time.

In the above-described embodiment, the image pickup device 1
The A / D converter 14, the image processing unit 15, and the image memory 18 are provided separately from the device 3, but the configuration is not limited to this. For example, the A / D conversion unit 14, the image processing unit 1
5 and at least one of the image memories 18 may be formed integrally with the image sensor 13 (so-called monolithic or one-chip).

Further, in the above-described embodiment, in step S13, the resolution of the image data is converted according to the display resolution of the monitor. However, the present invention is not limited to this. For example, the resolution conversion in step S13 can be omitted by presetting the distributed image data to a resolution suitable for the display resolution of the monitor.

[0071]

According to the first aspect of the present invention, the following effects can be obtained. The pixel outputs generated together on the light receiving surface are classified and arranged for each type of accumulation time, and become image data of a plurality of frames. As a result, image data of a plurality of frames having different accumulation times (that is, exposure conditions) can be obtained. That is,
Image data suitable for use in auto bracketing can be obtained. The image data of a plurality of frames are generated in a state of being mixed on the light receiving surface. Therefore, it is not necessary to repeat the imaging operation (charge accumulation → charge reading) for the number of image data, and it is possible to reduce the required imaging time to the level of normal imaging. Since the time required for shooting is shortened in this way,
The usability of auto bracketing in handheld shooting can be improved. Since one frame of image data is formed by classifying the pixel outputs on the light receiving surface, the number of pixels is smaller than the total number of pixels on the light receiving surface. This is disadvantageous in terms of image quality. But,
If the original number of pixels of the image sensor is about several times the number of pixels required by the user, the image quality does not substantially matter. Rather, the process of reducing the number of pixels can be omitted. Furthermore, the time required for image processing can be reduced by the small number of pixels. In addition, the buffer capacity of image data can be saved by the small number of pixels. Further, since the resolution of the image data is close to the display resolution of the monitor, the monitor display processing is simplified. The synergistic effect of such an effect makes it possible to significantly reduce the processing time of the auto bracketing.

In the image pickup apparatus according to the second aspect, image data of a plurality of frames are mixedly generated on the light receiving surface within the same exposure period. Therefore, the image data of multiple frames
These are image data within the same exposure period, and the shutter timings are substantially equal. Accordingly, the user only has to select a photo opportunity and start the exposure period, and can select image data with more appropriate exposure conditions from image data having the same photo opportunity. As a result, it is possible to easily obtain image data satisfying both the photo opportunity and the exposure condition.

In the image pickup apparatus according to the third aspect, pixel outputs having different accumulation times are mixedly generated on the light receiving surface by changing the timing of discharging invalid charges. In this case, there is no need to particularly change the readout timing of the pixel output. Therefore, the configuration is suitable when the configuration related to reading out pixel outputs is not significantly changed.

In the imaging device according to the fourth aspect, by changing the readout timing of the pixel output, the pixel outputs having different accumulation times are generated on the light receiving surface. In this case, there is no need to particularly change the timing of discharging the invalid charges. Therefore, the configuration is suitable when the configuration related to the discharge of the ineffective charges is not significantly changed.

An electronic camera according to a fifth aspect includes the “imaging device according to any one of the first to fourth aspects”. The electronic camera realizes the following two operation modes by controlling the imaging device. Auto bracketing mode for generating multiple image data with different accumulation times. By this auto bracketing mode, the effect of any one of claims 1 to 4 described above can be obtained. A normal imaging mode in which the accumulation time captures one type of image data. In the normal shooting mode, a normal shooting operation can be realized using the “imaging device according to any one of claims 1 to 4”. Therefore, there is no need to redundantly provide another imaging device for normal photographing, and the configuration of the electronic camera can be simplified.

In the electronic camera according to the present invention, a plurality of image data picked up in the auto bracketing mode are selected and stored according to the user's selection. Therefore, there is no need for a troublesome operation such as redoing the shooting in response to the user's selection, and a light shooting operation is realized.

In the electronic camera according to the seventh aspect, the photographing is performed again according to the user's selection in the auto bracketing mode. Therefore, high-resolution image data can be obtained by re-photographing, and a photographing operation that emphasizes image quality is realized.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an electronic camera 11. FIG.

FIG. 2 is a diagram showing an internal configuration of an image sensor 13.

FIG. 3 is a flowchart illustrating an operation of the electronic camera 11;

FIG. 4 is an explanatory diagram illustrating an operation of the imaging device 13a in a normal shooting mode.

FIG. 5 is an explanatory diagram showing an operation of the imaging device 13a in an auto bracketing mode.

FIG. 6 is an explanatory diagram illustrating an operation of the imaging device 13a according to the second embodiment.

FIG. 7 is an explanatory diagram illustrating an operation of an imaging device 13a according to a third embodiment.

FIG. 8 is a diagram illustrating a configuration of an imaging device 30 according to a fourth embodiment.

FIG. 9 is a diagram for explaining charge discharge of the imaging device 30.

FIG. 10 is a diagram illustrating an operation of the imaging device 30 during an accumulation time T1.

FIG. 11 is a diagram illustrating an operation of the imaging device 30 during an accumulation time T2.

FIG. 12 is a diagram illustrating an operation of the imaging device 30 during an accumulation time T3.

FIG. 13 is a diagram illustrating image reading by the imaging device 30.

[Explanation of symbols]

 PD photodiode QA amplifying element QP MOS switch QX MOS switch QH MOS switch 1 unit pixel 2 vertical read line 3 vertical scan circuit 5 read circuit 7 horizontal read line 8 horizontal scan circuit 11 electronic camera 12 shooting lens 13 image pickup device 13a image pickup device 14A / D conversion unit 15 image processing unit 16 bus 17 MPU 18 image memory 19 monitor 20 image display circuit 21 compression recording unit 22 operation unit 30 imaging device 31 light receiving element 32 vertical CCD 33 gate 34 vertical scanning circuit 35 horizontal CCD 36 image distribution unit

Claims (7)

[Claims] A plurality of light-receiving pixels arranged on a light-receiving surface and accumulating a pixel output in accordance with incident light; and changing a storage time of the light-receiving pixels into a pixel unit and / or a line unit. An accumulation control unit that generates the different pixel outputs so as to be substantially evenly distributed on the light receiving surface; and classifies the pixel outputs generated by the accumulation control unit for each type of the accumulation time. An image pickup apparatus comprising: an image generation unit that generates a plurality of different image data. 2. The imaging device according to claim 1, wherein the accumulation control unit is configured to:
An imaging apparatus, wherein by changing the accumulation time on a pixel basis and / or a line basis, the pixel outputs having different accumulation times are generated so as to be substantially evenly distributed on the light receiving surface. 3. The image pickup apparatus according to claim 1, wherein the accumulation control unit changes a timing of discharging the invalid charges from the light receiving pixels in a pixel unit and / or a line unit, thereby causing the accumulation. An imaging apparatus, wherein the pixel outputs at different times are generated so as to be substantially uniformly distributed on the light receiving surface. 4. The image pickup apparatus according to claim 1, wherein the accumulation control unit changes a timing of reading the pixel output from the light receiving pixels in a pixel unit and / or a line unit, so that the accumulation is performed. An imaging apparatus, wherein the pixel outputs at different times are generated so as to be substantially uniformly distributed on the light receiving surface. 5. An imaging device according to claim 1, further comprising: a control unit configured to control an imaging operation of the imaging device, wherein the control unit selects a selectable operation mode. An auto-bracketing mode for controlling the imaging device to generate a plurality of the image data having different accumulation times, and a normal shooting mode for controlling the imaging device to capture the image data of one type of the accumulation time. An electronic camera comprising: 6. The electronic camera according to claim 5, wherein a plurality of the image data captured in the auto bracketing mode are displayed in a comparative manner, and an input unit that receives an image selection operation by a user; An electronic camera, comprising: a selection storage unit configured to store the selected image data. 7. The electronic camera according to claim 5, further comprising: an input unit configured to display a plurality of pieces of the image data captured in the auto bracketing mode, and to receive an image selection operation by a user. An electronic camera that sets the accumulation time of the image data selected by the input unit and executes the normal shooting mode.