JP2000253415A - Digital camera and image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a digital camera in which the generation of noise is prevented at a low cost. SOLUTION: A primary color filter is fitted to the front of a CCD imager 20. An optimum shutter speed is calculated on the basis of a camera signal outputted from the imager 20 at the time of preexposure. When the calculated optimum shutter speed is low, a timing generator 22 drives the imager 20 by a pixel mixed reading procedure. Electric charges are read out first from part of light receiving elements to a vertical transfer register and then transferred in the vertical direction. When the charges are transferred by a prescribed distance, charges are read out from another part of the light receiving elements. Thus electric charges corresponding to the same color element are mixed in the vertical transfer register. That is, filter processing for removing folded components is executed in the image 20. Consequently, noise can be removed without newly preparing a filter circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital camera and an image pickup apparatus, and more particularly to a digital camera which reads out electric charges from a light receiving element of a CCD imager and generates a low-resolution camera signal, and to such a digital camera. Related to an imaging device.

[0002]

2. Description of the Related Art In a conventional digital camera of this type,
In the case where charges are read out from the CCD imager while being read out, the read charges are individually transferred and output individually from the CCD imager.

[0003]

However, thinning-out reading of charges is equivalent to sampling of charges, and according to the sampling theorem, an aliasing component is included in an output camera signal. Although a filter may be provided to remove such aliasing components, the cost is increased by the addition of the filter.

[0004] Therefore, a main object of the present invention is to provide a digital camera capable of preventing generation of noise at low cost.

Another object of the present invention is to provide an image pickup apparatus capable of preventing generation of noise at low cost.

[0006]

According to a first aspect of the present invention, there is provided an interline transfer type CCD imager having a plurality of light receiving elements and a plurality of vertical transfer registers, wherein a plurality of color elements are arranged and one light receiving element is provided. A color filter corresponding to one color element, and driving means for driving the CCD imager. The color filter has a vertical column in which color elements of a plurality of colors are arranged. A digital camera that drives a CCD imager to be mixed on a vertical transfer register corresponding to a vertical column.

A second invention is an interline transfer type C having a plurality of light receiving elements and a plurality of vertical transfer registers.
A CD imager, a color filter in which a plurality of color elements are arranged and one color element corresponds to one light receiving element, and a driving means for driving a CCD imager, wherein the color filter has a plurality of color elements arranged The driving device is an imaging device having a vertical column and driving the CCD imager such that charges corresponding to the same color element are mixed on a vertical transfer register corresponding to the vertical column.

[0008]

According to the first invention, the CCD imager of the interline transfer system has a plurality of light receiving elements and a plurality of vertical transfer registers, and a plurality of color elements forming a color filter are provided one by one for the plurality of light receiving elements. Corresponding. The CCD imager is driven by driving means. Here, the color filter has a vertical column in which color elements of a plurality of colors are arranged. Further, the driving means drives the CCD imager such that electric charges corresponding to the same color elements are mixed on the vertical transfer register corresponding to the above-mentioned vertical column.

By driving the CCD imager so that charges corresponding to the same color elements are mixed, a filtering process for removing aliasing components is performed in the CCD imager. Therefore, noise can be removed without newly providing a filter circuit.

In one embodiment of the present invention, the driving means comprises:
It includes a first readout unit, a vertical transfer unit, and a second readout unit. The first charge generated by the first light receiving element is the first charge
Read by a read means into a vertical transfer register,
The data is vertically transferred by the vertical transfer means. When the first charge is subjected to vertical transfer for a predetermined distance, the second charge generated by the second light receiving element is read out to the vertical transfer register by the second reading means. Here, the first light receiving element and the second light receiving element correspond to the same color element.

Preferably, two color elements are alternately arranged in the above-mentioned vertical column, and the predetermined distance corresponds to the length of the two light receiving elements in the vertical direction.

In another embodiment of the present invention, the color filter is a filter in which primary color components are arranged in a Bayer array.

In another embodiment of the present invention, the vertical transfer register is formed by a plurality of metals, and at least three metals are assigned to one light receiving element.

In still another embodiment of the present invention, a subject image is exposed to a CCD imager by exposure means. Here, the optimum exposure amount of the CCD imager is calculated by the calculation means, and the calculated optimum exposure amount is set in the exposure means by the setting means. The second reading unit is disabled by the disable unit according to the optimal exposure amount.

Preferably, the optimum exposure amount is defined based on the shutter speed, and the disabling means disables the second reading means when the shutter speed becomes higher than a predetermined value.

According to the second invention, the CCD imager of the interline transfer system has a plurality of light receiving elements and a plurality of vertical transfer registers, and a plurality of color elements forming a color filter are provided one by one for the plurality of light receiving elements. Corresponding. The CCD imager is driven by a driving pulse generated from the generating means. Here, the color filter has a vertical column in which color elements of a plurality of colors are arranged. The generating means generates a pulse for driving the CCD imager such that charges corresponding to the same color elements are mixed on the vertical transfer registers corresponding to the vertical columns.

[0017]

According to these inventions, the CCD imager is driven so that charges corresponding to the same color elements are mixed, so that a filtering process for removing aliasing components is performed in the CCD imager. Therefore, noise can be removed without newly providing a filter circuit.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0019]

Referring to FIG. 1, a digital camera 10 of this embodiment includes a lens 12. FIG. The light image incident from the lens 12 passes through the aperture unit 16 and is
Irradiates the CCD imager 20 of the interline transfer system provided in the. As shown in FIG.
2, a plurality of light receiving elements 20a are formed, and each light receiving element 20a forms each pixel of the CCD imager 20. On the front surface of the light receiving element 20a, as shown in FIG.
Primary color filter 2 in which G and B color elements are Bayer arranged
0d is attached, and one of R, G and B color elements corresponds to each light receiving element 20a. That is, one color element corresponds to one light receiving element. The subject image is irradiated on the light receiving element 20a through such a primary color filter 20d and subjected to photoelectric conversion.

Here, the primary color filter 20a is divided into two lines.
When considered as a set of color blocks of two pixels, the G color element is arranged on one diagonal of the color block, and the R and B color elements are arranged on the other diagonal. A plurality of such color blocks exist on the primary color filter 20a, and each color block is adjacent to each other in both the vertical direction and the horizontal direction. When attention is paid to a vertical column forming the primary color filter 20a, an R color element and a G color element are alternately arranged for each pixel in a certain vertical column, and a G color element and a B color element are arranged in another vertical column. Are alternately arranged for each pixel. That is, in any vertical column, two color elements are alternately arranged for each pixel.

Returning to FIG. 2, the CCD imager 20
A plurality of light receiving elements 20a corresponding to each pixel;
0a, a plurality of vertical transfer registers 20b for vertically transferring the charges which have been photoelectrically converted and accumulated, and a horizontal transfer register arranged at the end of the vertical transfer registers 20b for transferring the charges transferred by the vertical transfer registers 20b in the horizontal direction. And a transfer register 20c, and is driven by a drive pulse output from a timing generator (TG) 22. Here, as the driving pulse, a read pulse for reading out the electric charge from the light receiving element 20a to the vertical transfer register 20b, a vertical transfer pulse for transferring the read out electric charge in the vertical direction line by line, and the electric charge in the horizontal transfer register 20c by 1 A horizontal transfer pulse for transferring pixels in the horizontal direction, the light receiving element 20a during the non-exposure time, ie, the non-charge accumulation period
Overflow drain (not shown)
There is a sweeping pulse to sweep away.

When the camera mode is set by the mode setting button 46 and the release button 48 is pressed, first, a pre-exposure is performed, and the electric charge obtained by this is charged to CC.
It is read from the D imager 20. At the time of pre-exposure, the TG 22 controls the output period of the sweep-out pulse according to the initial shutter speed data set by the microcomputer 40. As shown in FIG. 4, the sweeping-out period starts from the beginning of one frame period of interest, and the end time of the sweeping-out period is controlled by shutter speed data. Thus, the charge accumulation period changes, and exposure at a desired shutter speed (exposure time) is realized.
Note that a technique of controlling the shutter speed by the output period of the sweep-out pulse is well known as an electronic shutter function.

A pixel signal (camera signal) output from the CCD imager 20 is converted into a digital signal, that is, pixel data by an A / D converter 24, and the pixel data is written to a RAM 26 by a write / read control circuit 28.
The pixel data stored in the RAM 26 is read by the same write / read control circuit 28 and input to the arithmetic circuit 30.

The input pixel data includes R, G and G
Has only one color component. Arithmetic circuit 30
Performs color interpolation and YUV conversion on such pixel data to generate Y data, U data, and V data.
The Y data is input to the weighting circuit 32.
The weighting circuit 32 multiplies the Y data by the weight held in the weight amount table 34. The weight amount table 34 receives the read address data from the write / read control circuit 28 and outputs a corresponding weight amount. By applying a weighting process to the Y data with this weighting amount, center-weighted photometry can be performed. The Y data output from the weighting circuit 32 is integrated by the integrator 36 every frame period. The calculator 38 divides the integrated data output from the integrator 36 by the sum of the weights, and calculates a luminance evaluation value to be evaluated for exposure adjustment. In addition,
The U data and V data calculated by the arithmetic unit 30 together with the Y data are provided to a white balance adjustment circuit (not shown).

The microcomputer 40 takes in the luminance evaluation value output from the computing unit 38 and updates the shutter speed based on the luminance evaluation value. When the optimum shutter speed (optimal exposure period) is calculated, the microcomputer 40 performs the main exposure. The camera signal generated by the main exposure is provided to the signal processing circuit 42 via the switch SW1.
Then, the image signal subjected to the predetermined signal processing is recorded on the recording medium 44.

The microcomputer 40 sets one of the thinning-out reading method and the pixel mixture reading method to the TG 22 according to the value of the optimum shutter speed. When attention is paid to four pixels that are continuous in the vertical direction, in the thinning-out reading method, charges are read from two predetermined pixels among the four pixels. On the other hand, in the pixel mixture readout method, charges are read out from all four pixels, and pixels having the same color component are mixed. Therefore, no matter which method is set, the number of pixels constituting the camera signal is the same.

Each of the readout methods will be described in detail with reference to vertically continuous pixels as shown in FIGS. 5 (A), 5 (B), 6 (A) and 6 (B). The vertical transfer register 20b is formed of a plurality of metals (electrodes) M, and three metals M are allocated to one light receiving element 20a (pixel). The color filter 20d is R,
Since G and B are Bayer-arranged primary color filters, R pixels and G pixels are alternately formed in odd-numbered vertical columns (odd columns) for each pixel, and in even-numbered vertical columns (even columns). G pixels and B pixels are alternately formed for each pixel. Focusing on the three metals M assigned to each pixel, a V1 pulse is applied to the top metal M,
Three pulses are applied to the center metal M, and a V2A or V2B pulse is applied to the bottom metal M. The application destination of the V2A pulse and the application destination of the V2B pulse are switched every two pixels. That is, when the V2A pulse is applied to the first half of the R pixel, the G pixel, the R pixel, and the G pixel in the odd-numbered columns, the V2B pulse is applied to the second half of the R and G pixels. Also in the even-numbered column, when the V2A pulse is given to the G pixel and the B pixel in the first half of the continuous four pixels, the V2B pulse is given to the second half G pixel and the B pixel.

As described above, in the CCD imager 20 in which three metals M are assigned to each light receiving element 20a, each pixel can be progressively scanned. This means that even when charges are read from all the light receiving elements 20a at the same time, the charges read from the adjacent light receiving elements 20a are individually transferred. That is, even when all pixels are read, the R, G, and B signals obtained from each pixel are output from the CCD imager 20 without being mixed with each other.

Referring to FIGS. 5A and 5B,
When the thinning-out reading method is selected, reading of charges from the pixel to which the V2B pulse is applied is stopped, and the V2A pulse is read out.
Charge is read out only from the pixel to which the pulse is applied.
Therefore, charges for two pixels that are continuous in the vertical direction are read out every two pixels. For odd columns, the R4 signal,
The G4 signal, the R2 signal, and the G2 signal are read and individually transferred on the corresponding vertical transfer register 20b. On the other hand, the G4 signal, B4 signal, G2 signal and B
Two signals are read out, and are also individually transferred on the corresponding vertical transfer registers 20b. That is, the color blocks to be read when the thinning-out reading method is selected are the color blocks existing every other block in the vertical direction. The pixel signals transferred in the vertical direction are thereafter subjected to horizontal transfer for each line. The camera signal output from the CCD imager 20 includes all the R, G, and B color components.

Referring to FIGS. 6A and 6B,
When the pixel mixture reading method is selected, charges are read from all the pixels. However, first, charges are read from the pixel to which the V2A pulse is applied, and when the read charges are transferred by two pixels in the vertical direction, the charge is read from the pixel to which the V2B pulse is applied. In the odd columns, first, the R4 signal, the G4 signal, the R2 signal, and the G2 signal are read out to the vertical transfer register 20b and individually transferred on the vertical transfer register 20b. When the vertical transfer for two lines is completed, the R3 signal, the G3 signal, the R1 signal, and the G1 signal are read. As a result, charges corresponding to the same color element are mixed on the vertical transfer register 20b, and the (R3 + R4) signal, the (G3 + G4) signal, and the (R
1 + R2) signal and (G1 + G2) signal are obtained.
In the even-numbered column, first, the G4 signal, the B4 signal, the G2 signal, and the B2 signal are read out to the vertical transfer register 20b, and when these signals are vertically transferred by two lines, the G3 signal is output.
The signal, B3 signal, G1 signal and B1 signal are read out to the same vertical transfer register 20b. This gives (G
3 + G4) signal, (B3 + B4) signal, (G1 + G2)
Signal and (B1 + B2) signal are transferred to the vertical transfer register 20.
b.

That is, when the pixel mixed reading method is selected, first, pixel signals are read from every other color block in the vertical direction. Then, when the pixel signals are transferred for two lines in the vertical direction, the pixel signals are read from the remaining color blocks. As a result, pixel signals having the same color component are mixed on the vertical transfer register 20b. The mixed pixel signals are vertically transferred so that different color components are not mixed, and then horizontally transferred line by line. That is, a camera signal including all the R, G, and B color components is output from the CCD imager 20.

In the thinning-out reading method, the aliasing component is included in the camera signal according to the sampling theorem. For this reason, unless the aliasing component is removed from the camera signal by the filtering process, noise appears.
On the other hand, in the pixel-mixing readout method, when one pixel signal is vertically transferred by two lines, the other pixel signal is read out and each pixel signal is mixed.
Such a transfer method is equivalent to the filter processing shown in FIG. That is, when attention is paid to the R1 signal and the R2 signal, the R1 signal is read with a delay to the R2 signal, and both are added. When the pixel mixture readout method is selected, the filtering process is performed in this way, and the aliasing component is removed from the camera signal.

The TG 22 for transferring charges is configured as shown in FIG. The H counter 22a is a counter that counts the number of horizontal pixels. The horizontal count value is reset in response to a shooting instruction or a horizontal synchronization signal from the microcomputer 40, and is incremented in response to a pixel clock. On the other hand, the V counter 22b is a counter that counts the number of vertical lines. The vertical count value is reset in response to a shooting instruction or a vertical synchronization signal, and is incremented in response to a horizontal synchronization signal. Both the horizontal count value and the vertical count value are provided to decoders 22c to 22k. The decoder 22c generates a charge sweep-out pulse SUB based on these count values and shutter speed data from the microcomputer 40. The decoder 22d generates a horizontal transfer pulse H1 (H1 pulse) from the input count value, and the decoders 22e and 22f generate a vertical transfer pulse V1 (V1 pulse) and a vertical transfer pulse V3 (V3 pulse) from the count value.
Pulse).

Further, the decoders 22g to 22k respectively provide timing pulses XV2A, XSGA, XV2B
1, XV2B2 and XSGB. this house,
The timing pulses XV2A and XSGA are directly supplied to the driver 22m. On the other hand, the timing pulses XV2B1 and XV2B2 are given to the driver 22m via the switch SW2, and the timing pulse XSG
B is directly provided to the driver 22m. Microcomputer 40
Is the switch S when the thinning-out reading method is selected.
W2 is connected to the side of the decoder 22i, and the switch SW2 is switched to the decoder 22j when the pixel mixture readout system is selected.
To the side. Therefore, the timing pulse XV2B1 is input to the driver 22n at the time of thinning-out reading, and the timing pulse XV2B2 is input to the driver 22n at the time of pixel mixed reading. Drivers 22m and 22n generate vertical transfer pulse V2A (V2A pulse) and vertical transfer pulse V2B (V2B pulse) based on the applied timing pulse, respectively.

Therefore, as can be seen from FIGS. 9 and 12, the H1, V1, V2A, and V3 pulses are common to each read mode, but the V2B pulse differs depending on the read mode. At the time of thinning-out reading, only the V2A pulse has a positive polarity in the A period,
As a result, charges are read out only from the pixels to which the V2A pulse is applied. That is, the process of reading the charge from the pixel to which the V2B pulse is applied is disabled. On the other hand, at the time of pixel mixed reading, in the same A period, the V2A pulse first has a positive polarity, and then the V2B pulse has a positive polarity. Therefore, after the charge is read from the pixel to which the V2A pulse is applied, the charge is read from the pixel to which the V2B pulse is applied. Note that the V2A pulse and V2B
In the pulse, a portion having a positive polarity corresponds to a read pulse.

When the thinning-out reading method is selected, each pulse changes in period A as shown in FIG. When the V2A pulse becomes a positive level, the charge of the corresponding pixel is read out to the vertical transfer register. After the reading, the V2A pulse and the V2B pulse simultaneously take the negative level twice, whereby charges are transferred in the vertical direction by two lines. As can be seen from FIG. 11, the V2A pulse and the V2B pulse have a negative level at a predetermined timing even in periods other than the period A, and the V1 pulse and the V3 pulse have a negative level at substantially the same timing. As a result, charges are transferred in the vertical direction. The charges transferred vertically are then transferred horizontally by the H1 pulse and output from the CCD imager 20.

Each pulse changes as shown in FIG. 13 during the period A when the pixel mixture readout method is selected.
The V2A pulse goes to the plus level once, and then the V2A and V2B pulses go to the minus level twice at the same time. As a result, the initially read charges are vertically transferred for two lines. Subsequently, the V2B pulse takes a positive level once, and the electric charge read out in response to this becomes
It is mixed with the charge transferred vertically. In periods other than the period A, each pulse changes as shown in FIG. 14, whereby the mixed charges are transferred in the vertical direction. After the vertical transfer, the mixed charges are horizontally transferred by the H1 pulse.

The microcomputer 40 calculates the main exposure amount by processing the flowcharts shown in FIGS. 15 and 16, and records the photographed subject image on the recording medium 44. Note that the processing of this flowchart is started in response to the pressing of the release button 48.

First, the aperture is set to a predetermined F value in step S1, and the exposure time (shutter speed) is initialized in step S3. That is, for example, the initial shutter speed data of 1/250 second is set in the TG 22. Subsequently, in step S4, the switch SW2 is switched to the decoder 22i to set the thinning-out reading method to TG22, and in step S5, the TG 22 is instructed to shoot. The TG 22 performs pre-exposure according to the set shutter speed data, and reads out the generated charges by a thinning-out reading method.

The microcomputer 40 fetches the luminance evaluation value output from the calculator 38 based on the camera signal obtained by the pre-exposure in step S7, and calculates the next shutter speed in step S9. Specifically, the luminance evaluation value is compared with a target evaluation value obtained in an optimal exposure state, and a shutter speed at which the luminance evaluation value matches the target evaluation value is calculated. For example, if the luminance evaluation value is “50” and the target evaluation value is “100”, the luminance is only half of the optimal state, and the next exposure time is 1/125 second. The microcomputer 40 updates the shutter speed data set in the TG 22 in step S11, and determines whether or not the processing in steps S5 to S11 has been performed three times in step S13. That is, the above process is repeated three times in order to accurately calculate the shutter speed (optimal shutter speed) at which a desired exposure amount can be obtained.

If "YES" is determined in the step S13, the microcomputer 40 compares the optimal shutter speed (optimal exposure period) with time data of 1/1000 second in a step S15. If the optimum exposure period is 1/1000 second or longer than 1/1000 second, the switch SW2 is switched to the decoder 22j in step S17 to set the pixel mixed reading method. Then, the process proceeds to step S19. On the other hand, if the optimum exposure period is shorter than 1/1000 second, step S19 is performed while the thinning-out reading method is maintained.
Proceed to. Therefore, the optimal exposure period is, for example, 1/50
If it is 0 second, the pixel mixture reading method is selected.

Since the electronic shutter shown in FIG. 4 is used for the shutter control in this embodiment, the necessary charges are accumulated after the unnecessary charges are swept away, and the charges are accumulated when a predetermined accumulation period has elapsed. Is read. Then, in the pixel mixture readout method in which pixels are read out at different times, the influence of a shift in readout time increases as the shutter speed increases. That is, the difference between the charge amount read first and the charge amount read later increases as the exposure time becomes shorter. For this reason, in this embodiment, the charge reading method is switched according to the value of the optimal shutter speed. On the other hand, the switching threshold is set to 1/100
The reason for setting the time to 0 second is that it takes 1/1000 second to transfer the read charges for one line.

Thereafter, the microcomputer 40 instructs the TG 22 to perform photographing in step S19. For this reason, the main exposure is performed at the optimum shutter speed, and the charges generated thereby are read out in a desired manner. Thus C
When the camera signal is output from the CD imager 20, the microcomputer 40 performs a recording process in step S21. The camera signal is input to the signal processing circuit 42 via the switch SW1, and is subjected to predetermined processing. And the signal processing circuit 4
2 is recorded on the recording medium 44.

According to this embodiment, by selecting the pixel mixture readout method, a filtering process as shown in FIG. 14 is performed in the CCD imager 20, so that the camera signal is looped back without adding a filter circuit. Ingredients can be removed. In addition, since the pixel-mixed readout method is selected only when the optimum shutter speed is low, the charge amount does not greatly deviate between the first readout charge and the second readout charge.

Although the present embodiment has been described using the aperture priority mode, it goes without saying that the present invention can be applied to the shutter speed priority mode and the program AE mode. In the shutter speed priority mode, the exposure amount changes by adjusting the aperture amount, and in the program AE mode, the exposure amount changes by adjusting both the shutter speed and the aperture amount. Therefore, the shutter speed that can be set in the shutter speed priority mode is 1 /
If the speed is limited to less than 1000 seconds, a camera signal that does not include aliasing components can always be obtained.

Further, in this embodiment, only the case where a still image is photographed has been described. However, it is needless to say that the present invention can be applied to moving image photographing. In addition, the present invention
The present invention is also applicable to a through image mode for displaying a real-time moving image (through image) on a liquid crystal display.

Further, in this embodiment, the shutter speed is controlled by the electronic shutter. However, at the time of photographing a still image, the shutter speed may be controlled by a so-called mechanical shutter. Further, in this embodiment, the thinning-out reading method is set at the time of the pre-exposure. However, it is needless to say that the pixel mixture reading method may be set instead. Furthermore, in this embodiment, a primary color filter in which R, G, and B color elements are arranged in a Bayer array is used. However, a complementary color filter having Ye, Cy, Mg, and G color elements as shown in FIG. It may be used instead of the primary color filter.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is an illustrative view showing a CCD imager;

FIG. 3 is an illustrative view showing a primary color filter;

FIG. 4 is an illustrative view showing one portion of an operation of the embodiment in FIG. 1;

FIG. 5 is an illustrative view showing one portion of an operation in a thinning-out reading mode;

FIG. 6 is an illustrative view showing one portion of an operation in a pixel mixture reading mode;

FIG. 7 is a block diagram illustrating an example of a filter.

FIG. 8 is a block diagram illustrating an example of a TG.

FIG. 9 is a timing chart showing a part of the operation in the thinning-out reading mode.

FIG. 10 is a timing chart showing another part of the operation in the thinning-out reading mode.

FIG. 11 is a timing chart showing another part of the operation in the thinning-out reading mode.

FIG. 12 is a timing chart showing a part of the operation in the pixel mixture read mode.

FIG. 13 is a timing chart showing another part of the operation in the pixel mixture read mode.

FIG. 14 is a timing chart showing another part of the operation in the pixel mixture read mode.

FIG. 15 is a flowchart showing a part of the operation of the embodiment in FIG. 1;

FIG. 16 is a flowchart showing another portion of the operation of the embodiment in FIG. 1;

FIG. 17 is an illustrative view showing a complementary color filter;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Digital camera 14 ... Imaging device 20 ... CCD imager 22 ... Timing generator 40 ... Microcomputer

Claims (8)

[Claims] An interline transfer type CCD imager having a plurality of light receiving elements and a plurality of vertical transfer registers, a color filter in which a plurality of color elements are arranged and one color element corresponds to one light receiving element, and Driving means for driving the CCD imager, the color filter has a vertical column in which color elements of a plurality of colors are arranged, and the driving means has a vertical column in which electric charges corresponding to the color elements of the same color correspond to the vertical columns. A digital camera that drives the CCD imager to be mixed on a transfer register. 2. The driving device according to claim 1, wherein the driving unit includes a first reading unit that reads the first charge generated by the first light receiving element into the vertical transfer register, a vertical transfer unit that transfers the first charge in a vertical direction, and the A second read unit that reads the second charge generated by the second light receiving element into the vertical transfer register when one charge has been vertically transferred by a predetermined distance, the first light receiving element and the second light receiving means; The digital camera according to claim 1, wherein the elements correspond to the same color element. 3. The digital camera according to claim 2, wherein two color elements are alternately arranged in the vertical column, and the predetermined distance corresponds to a vertical length of two light receiving elements. 4. The digital camera according to claim 1, wherein said color filter is a filter in which primary color components are arranged in a Bayer array. 5. The digital camera according to claim 1, wherein said vertical transfer register is formed of a plurality of metals, and at least three metals are assigned to one light receiving element. 6. Exposure means for exposing a subject image to said CCD imager, calculation means for calculating an optimum exposure amount of said CCD imager, setting means for setting said optimum exposure amount to said exposure means, and 2. The digital camera according to claim 1, further comprising a disabling unit that disables the second reading unit in response. 7. The method according to claim 6, wherein the optimal exposure amount is defined based on a shutter speed, and the disabling means disables the second reading means when the shutter speed becomes higher than a predetermined value. Digital camera as described. 8. An interline transfer CCD imager having a plurality of light receiving elements and a plurality of vertical transfer registers, a color filter in which a plurality of color elements are arranged and one color element corresponds to one light receiving element, and Driving means for driving the CCD imager, the color filter has a vertical column in which color elements of a plurality of colors are arranged, and the driving means has a vertical column in which electric charges corresponding to the color elements of the same color correspond to the vertical columns. An imaging device for driving said CCD imager to be mixed on a transfer register.