JP3483766B2 - Imaging device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for writing a signal obtained from a solid-state image sensor into a storage means and reading the signal from the storage means at a speed different from the writing speed. The present invention relates to an imaging device capable of obtaining a motion image. 2. Description of the Related Art A method of obtaining an image by performing photoelectric conversion using a solid-state imaging device, writing an obtained video signal to a storage means, reading the video signal from the storage means, and obtaining a slow motion video is known. And JP-A-2-57074. In this method, the solid-state imaging device is driven at an integral multiple of the original speed, and the imaging signal is output several times during the original one-field period to output a video signal. This is for obtaining a reproduced video. A conventional imaging method for obtaining a slow motion image will be described with reference to FIGS. 6, 7 and 8. FIG. FIG. 6 is a block diagram showing a configuration of a conventional imaging device. FIG. 7 is a timing chart of a conventional imaging method without slow motion using the configuration of FIG. 6, and FIG. 8 is a timing chart when a slow motion video is obtained using the configuration of FIG. In FIG. 6, reference numeral 60 denotes an imaging unit that outputs a video signal using a solid-state imaging device, and 61 denotes a video recording / reproducing unit that records the output of the imaging unit 60 to obtain a slow-motion video and performs slow-motion reproduction. In the imaging unit 60, RG
G solid-state image sensor 602, R solid-state image sensor 603, B solid-state image sensor 60
4 are fixed, and these three solid-state imaging devices are driven by a three-plate solid-state imaging device driving circuit 608 to output photoelectrically converted electrical signals of RGB. The output signal of the G solid-state imaging device 602 is amplified by the G process circuit 605 and output as a video signal Ga. Similarly, the electric signals output from the R solid-state image sensor 603 and the B solid-state image sensor 604 are amplified by the R process circuit 606 and the B process circuit 607, respectively, and the video signals Ra, B
Output as a. As the solid-state imaging device to be used, the one having the configuration shown in FIG. 2 can be used. Next, a conventional video signal output method without slow motion will be described with reference to a block diagram of a solid-state image sensor of FIG. 2 and a timing chart of FIG. G solid-state image sensor 6
The photodiode arrays 201 of the 02, R solid-state imaging device 603, and B solid-state imaging device 604 perform photoelectric conversion during the accumulation period P of the period A'B'C 'to accumulate charges. All the photoelectrically converted charges are supplied to the vertical CCD 202 during the vertical transfer period P in the vertical blacking period at the transition between the periods C 'and D'.
And is transferred in the vertical direction to reach the storage area 22. The signal is transferred by the horizontal CCD 203 during the horizontal transfer period P ″ of the period D ′ E ′ F ′, and is output from the amplifier 204 to the G process circuit 605, the R process circuit 606, and the B process circuit 607 as an electric signal of video 1. On the other hand, even during the period in which the image 1 is being output, the charge for the next field is accumulated by photoelectric conversion as the accumulation period Q. The accumulated charge is applied to the vertical transfer period Q during the vertical blacking period at the transition between the period F 'and the period G'.
The data is read out to the CD 202, transferred in the vertical direction, reaches the storage area 22, is transferred by the horizontal CCD 203 during a horizontal transfer period Q after the period G ', and is output from the amplifier 204 as a video 2 as a G process circuit 605 and an R process circuit. 60
6. Output to the B process circuit 607. In this manner, an image can be output by lighting one field per field. Next, a conventional video signal output method for obtaining a three-fold slow motion video will be described with reference to the configuration diagram of the solid-state imaging device of FIG. 2 and the timing diagram of FIG.
Each timing shown in FIG. 7 is reduced to 1/3 to perform imaging.
The photodiode array 201 of the G solid-state image sensor 602, the R solid-state image sensor 603, and the B solid-state image sensor 604 performs photoelectric conversion only during the accumulation period A and accumulates charges. All the photoelectrically converted electric charges are transferred to the vertical transfer period A during the vertical blanking period between the period A where the field changes and the period B,
The data is read out to the CD 202 and transferred in the vertical direction to reach the storage area 22. During the horizontal transfer period A, the horizontal CCD 20
3 and output from the amplifier 204 to the G process circuit 605, the R process circuit 606, and the B process circuit 607 as an electric signal of the image 1. On the other hand, in the period during which the image 1 is being output, the charge for the next field is accumulated by photoelectric conversion as the accumulation period B, and the accumulated charge is during the vertical blacking period at the transition between the period B and the period C. The data is read out by the vertical CCD 202 during the vertical transfer period B, and is vertically transferred to reach the storage area 22. The data is transferred by the horizontal CCD 203 during the horizontal transfer period B, and
4 to the G process circuit 605, R process circuit 606, and B process circuit 607 as video 2. Images 3 to 7 can be obtained by similar operations. In this way, the imaging unit 60 can output an image by lighting three fields per field. Next, the video signals Ga, Ra, and Ba output from the video unit 60 are recorded in the video recording / reproducing unit 61, and 1 is applied to one field.
By performing a reproducing operation for outputting a field, the output of the slow motion video Rb, Gb, Rb can be realized. [0006] As described above, by shortening the lighting time per field to the solid-state imaging device by a fraction of an integer, and by driving the solid-state imaging device by an integral multiple, A 1 / integer slow motion image can be obtained. Meanwhile, a vertical transfer pulse for transferring all charges to the storage section during the vertical blanking period and a horizontal CC
For a horizontal transfer pulse for transferring charges by D, a steep waveform having a short rise time and a short fall time is required. In a high-definition imaging device, the driving frequency of the solid-state imaging device is increased, and thus the quality of these waveforms greatly affects the image quality. When implementing slow motion, noise is generated in the drive circuit as the drive frequency becomes an integer multiple, which may limit the improvement of the drive waveform quality. It may worsen, causing shading or lowering the resolution. An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide an imaging apparatus which can achieve both slow-motion image quality and function without deteriorating the quality of a driving waveform of a solid-state imaging device. . [0008] In order to achieve the above object, the G signal is composed of two solid-state imaging devices, and the R signal and the B signal are composed of two solid-state image sensors.
The above-mentioned claim, each of which is constituted by one solid-state imaging device.
Item 1. The image pickup apparatus according to Item 1, has a storage area capable of storing all charges for the immediately preceding field when charges are stored in a specific field period in the image pickup area, and performs image pickup only during the horizontal blanking period. by transferring the charges in the storage area from the area, it suppresses shading, so it is possible to prevent the deterioration of the resolution, also, for the G signal, which corresponds to the lighting time off
Field signal when starting to write to memory.
And start the light emission for the R and B signals at the lighting time.
Write the signal of the corresponding field to the memory and finish
By configuring to start reading from time,
Thus, the RGB signals can be output in the same phase . A first aspect of the present invention is directed to a solid-state imaging device having two solid-state imaging devices for outputting a G signal and outputting an R signal and a B signal. Each of the solid-state imaging devices has one element, performs imaging by alternately performing photoelectric conversion and outputting a signal, and the structure of all the solid-state imaging devices is one field immediately before performing the photoelectric conversion. An imaging apparatus configured to have an accumulation area capable of accumulating all electric charges of the imaging apparatus, wherein the imaging apparatus performs an operation of transferring electric charges from the imaging area to the accumulation area only during a horizontal blanking period. Which gives
Since the vertical transfer of all charges during the vertical blanking period is eliminated, the output waveform of the solid-state imaging device can be improved and shading can be suppressed. According to a second aspect of the present invention, photoelectric conversion is performed by allocating a light-receiving time of a photodiode several times to one field period, and the obtained signal is written to a storage means and read out at a low speed. An imaging apparatus for obtaining a motion image, wherein for a G signal, a reading operation is started when writing of a field signal corresponding to a lighting time is started, and for an R signal and a B signal, a reading operation of a field corresponding to a lighting time is performed. 2. The image pickup device according to claim 1, wherein the image is output after reading out the signal after the signal has been written, and has an effect that pixels of each color signal corresponding to the horizontal and vertical positions of the image pickup area can be obtained. Embodiment 1 Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a first embodiment of the present invention.
FIG. 2 shows a configuration of an imaging device according to the first embodiment corresponding to FIG. 2, and FIG. 2 shows a structure of a solid-state imaging device used in the imaging device according to the present embodiment. In FIG. 1, 1
Reference numeral 0 denotes an imaging unit that outputs a video signal using a solid-state imaging device. In the imaging unit 10, a G1 solid-state imaging device 10 is mounted on a four-plate prism 101 that performs color separation into R, G1, G2, and B.
2, G2 solid-state image sensor 103, R solid-state image sensor 104,
The B solid-state image pickup device 105 is fixed, and these four solid-state image pickup devices are driven by a four-plate solid-state image pickup device driving circuit 110, and output photoelectrically converted electrical signals of RGB. The output signal of the G1 solid-state imaging device 102 is G
The video signal G1 amplified by the one process circuit 106
Output as -n. The output signal of the G2 solid-state imaging device 103 is amplified by the G2 process circuit 107 and output as a video signal G2-n. R solid-state imaging device 10
Similarly, the electric signals output from the solid-state image sensor 4 and the output signal from the solid-state image sensor 105 are similarly processed in the R process circuit 108 and the B process circuit 1 respectively.
09 and output as video signals R-n and B-n. In the solid-state imaging device 20 shown in FIG. 2, a photodiode array 201 for performing photoelectric conversion and accumulating electric charges is provided.
And a vertical CCD 202 for transferring accumulated charges in the vertical direction. The electric charge transferred by the vertical CCD 202 is transferred in the horizontal direction by the horizontal CCD 203 and
Amplified at 04 and output. FIG. 3 shows the principle of G1, G2, R, and B signal output, and the output operation of the G1 signal will be described. Photodiode 2 of G1 solid-state imaging device 102
No. 01 performs photoelectric conversion during the accumulation period A to accumulate charges.
The electric charge after the photoelectric conversion is transferred to the vertical CCD 2 during the vertical transfer period A.
02. The accumulated charge passes through the accumulation area 22 at the time of B + C shown in FIG.
Reach 03. After the transfer by the horizontal CCD 203 in the horizontal transfer period A, the amplifier 204 and the G1 process circuit 10
6 and output as the image G1-1. Similarly, in the accumulation period C and the accumulation period E, the photodiode 201
Are output as a video G1-1 and a video G1-3 in the horizontal transfer period C and the horizontal transfer period E, respectively. As described above, the solid-state image pickup device itself has a structure having the storage area 22 capable of storing all charges for one field as in the prior art. According to the first embodiment, During the horizontal blanking period of the time B + C, charges are transferred from the imaging area 21 to the storage area 22 by one stage to the adjacent vertical CCD only during the horizontal blanking period. As a result, the transfer of the vertical CCD is not performed during the vertical blanking period, so that the occurrence of noise can be reduced and the resolution can be prevented from lowering. Therefore, since the quality of the driving waveform is not deteriorated, shading can be reduced. Note that the G2, R, and B signals can similarly transfer charges in the vertical CCD only during the horizontal blanking period. (Embodiment 2) FIG. 4 shows a second embodiment of the present invention.
13 shows an example of an imaging device according to Embodiment 2 of the present invention corresponding to FIG. In the second embodiment, an imaging unit 10 similar to FIG. 1 in which G1, G2, R, and B signals are output based on the principle of FIG.
The G field memory 40 is used to write each color signal to the memory and read and output the R signal and the B signal while expanding the R signal and the B signal from the memory so that they have the same phase as the G signal.
1, R field memory 402, B field memory 4
03 and a memory control circuit 4 for controlling these memories
04 and a time axis extending unit 40
And a video recording / reproducing unit 41 that reproduces a slow motion video in response to an output from the video camera. FIG. 5 shows the principle of the present embodiment. FIG. 5A shows the output of the image pickup unit 10, which is input to the time base expansion unit 40. G field memory 40
1 is written with the signal shown in FIG. The G signal written in the G field memory 401 is rearranged and divided into three, and Ga, Gb,
It is output from the time base extension unit 40 as a Gc signal. Also, an R field memory 402 and a B field memory 403
From FIG. 8, the R signal obtained by extending the time axis and dividing the signal into three is shown in FIG.
At the timings of Ra, Rb, and Rc in FIG.
The signals are output from the time base expansion unit 40 at the timings of a, Bb, and Bc. At this time, regarding the image G1-1,
When writing to the G field memory 401 starts, as shown by Ga in FIG.
The memory control circuit 404 expands and reads from
Controls writing and reading of the memory. Also RB
As for the -1 signal, when the writing to the R field memory 402 and the B field memory 403 is completed, FIG.
As shown by Ra and Ba in FIG.
02 and the B field memory 403, the memory control circuit 404 controls writing and reading of the memory so as to be read out. By the same memory control, R
A GB signal can be output, and signals having the same phase can be sequentially output. By recording this signal in the video recording / reproducing unit 41 and reproducing it after terminating the imaging, a slow motion video can be obtained as shown in FIG. As described above, according to the first embodiment of the present invention, charges are transferred vertically from the imaging area to the storage area only during the horizontal blanking period.
Since no charge is transferred during the vertical blanking period, noise during the vertical blanking period can be reduced. Further, since the driving waveform quality is not impaired, there is obtained an effect that shading can be suppressed, and a decrease in transfer efficiency can be suppressed to prevent a decrease in resolution. According to the second embodiment of the present invention, each color signal obtained from the solid-state imaging device is written into the memory,
G of R signal and B signal generated by driving the solid-state imaging device
Since reading is performed from the memory so as to correct the phase shift for the field period corresponding to the lighting time for the signal, it is possible to obtain a color slow-motion image without color shift.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a schematic configuration of an imaging device according to a first embodiment of the present invention. FIG. 2 shows a structure of a solid-state imaging device used in the imaging device according to the first embodiment of the present invention. FIG. 3 is a schematic diagram showing G1, G2, and G1 in Embodiment 1 of the present invention.
FIG. 4 is a schematic diagram illustrating an output principle of R and B signal outputs. FIG. 4 is a block diagram illustrating a schematic configuration of an imaging device according to a second embodiment of the present invention. FIG. 5 is a principle of a signal output according to the second embodiment of the present invention. FIG. 6 is a block diagram showing a schematic configuration of a conventional imaging device. FIG. 7 is a timing diagram of a conventional imaging method without slow motion. FIG. Timing diagram in the case [Description of symbols] 10 Imaging unit 101 Four-plate prism 102 G1 Solid-state imaging device 103 G2 Solid-state imaging device 104 R Solid-state imaging device 105 B Solid-state imaging device 106 G1 Process circuit 107 G2 process circuit 108 R process circuit 109 B Process circuit 110 Four-chip solid-state imaging device driving circuit 20 Solid-state imaging device 201 Photodiode row 202 Vertical CCD 203 Horizontal C CD 204 Amplifier 21 Imaging area 22 Storage area 40 Time axis expansion unit 401 G field memory 402 R field memory 403 B field memory 404 Memory control circuit 41 Video recording / reproducing unit 60 Imaging unit 601 Three-plate prism 602 G solid-state imaging device 603 R solid Image sensor 604 B solid-state image sensor 605 G process circuit 606 R process circuit 607 B process circuit 608 Three-chip solid-state image sensor drive circuit 61 Video recording / reproducing unit

Claims (1)

(57) Claims 1. A solid-state imaging device having two solid-state imaging devices that output a G signal and one solid-state imaging device that outputs an R signal and a B signal. Is a storage area in which imaging is performed by alternately performing photoelectric conversion and outputting a signal, and in which all the solid-state imaging devices have a structure capable of storing all charges of one field immediately before performing photoelectric conversion. And several times during one field period.
The photoelectric conversion is performed by allocating the daylighting time of the photodiode.
Write the obtained signal to the storage means and read it at a slow speed.
An imaging apparatus for obtaining a slow-motion image by out seen, no line operation for transferring electric charges in the storage area from the image area only in the horizontal blanking period, the signal of the field for the G signal corresponding to the lighting time
The read operation starts when writing to
Signal and B signal of the field corresponding to the lighting time
Reads and outputs video when signal writing is completed
An imaging device, comprising: