JPS5954383A - Method for driving solid-state image pickup device - Google Patents

Abstract

PURPOSE:To improve the picture quality, by changing the combination of 2 lines read out at the same time so as to attain the interlace operation to a charge transfer type solid-state image pickup device. CONSTITUTION:Photoelectric converting elements are arranged two-dimensionally. The signal charge stored in the photoelectric converting elements is shifted to a vertical CCD with a switch pulse phiV0. The shifted signal charge is transferred upward sequentially with pulse phiV1, phiV2 to shift the CCD of two lines reading out horizontally the signal charge during one horizontal period. In this case, a pulse consecutive for two pulses as 31, 32 and a pulse consisting of one pulse as 33, 34 are used. A field transferring the signal charge only for one stage during the horizontal blanking period of the 1st one horizontal period and a field transferring the two stages together are provided alternately and the combination of the two lines reading out at the same time is changed at each field.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a method for driving a solid-state imaging device, and particularly to driving a charge transfer solid-state imaging device that simultaneously reads out two lines of information η1 stored two-dimensionally. Regarding the method.

[Prior art]

An example of a two-dimensional surface imaging device using a conventional charge-coupled device (CCl) is shown in FIG.

2 is a light beam 111 that converts incident light into signal charges. This is a group of conversion elements. 11.12...IN is a charge-coupled device (CCD) for transferring the charge accumulated in the photoelectric conversion element section in the direction of the vertical arrow, and transfer pulses φ711 φ7
．． is synchronized with the horizontal pulse φ8 of the television signal.

The signal charge accumulated in the photoelectric conversion unit 2 is transferred to the adjacent CCD in the vertical direction by the switch pulse φVQ during the vertical retrace period.

The transferred signal lightning and load are pulses φ7□, φ synchronized with the horizontal pulse of the television signal. The signals are sequentially transferred in the G direction (horizontal CCD direction).

The convex part is a CCD that transfers a load in the horizontal direction, and the signal charge transferred from the CCU in the vertical Iμ direction in synchronization with the horizontal pulse of the television signal is transferred to the output terminal 4 by the horizontal pulse φ□ during the -horizontal period. output as a video signal.

When constructing a single-chip color imaging device using a charge transfer type solid-state imaging device using a charge-coupled device as described above, as shown in FIG. It is advantageous to form a set of two lines, read the signals of these two lines at the same time in the same horizontal period, and separate the obtained signals and send them to two horizontal columns (CCI).

-F The method for driving the single-chip color imaging device is described in detail in the specification of the patent application filed by the inventors separately from the present application (1M).

By the way, if interlacing operations can be performed in the heavy-duty solid-state imaging device described above, it is possible to reduce flicker on the screen without degrading the image quality, and it is possible to obtain a large vertical resolution. can.

[Object of the Invention] An object of the present invention is to provide a driving method for performing an interlacing operation on a charge transfer solid-state imaging device.

[Summary of the invention]

In order to achieve the above object 1, the present invention provides a charge transfer type solid-state imaging device with simultaneous two-line readout, in which signal charges transferred from a photoelectric conversion element to a vertical charge-coupled device are
By alternately providing fields that are transferred in only one stage and fields that are transferred in two stages at once during the horizontal retrace period of the first horizontal period, it is possible to change the combination of the two lines that are read out at the same time for each field. “Let it be a sign.

(Embodiment of the Invention) FIG. 3 shows a drive pulse waveform for performing the incline operation of the present invention in a two-line simultaneous readout solid-state imaging device. φ in the figure. , φ7. ('', the pulse that drives the vertical CCD shown in FIG. 2, φ7.-'' During the vertical blanking period (FIG. 3(d)), the vertical CCD ) represents the pulse that opens and closes the switch 23 for transferring the signal charge.

As shown in FIG. 3(a) and (b), in the first field, the signal charge number transferred from the first conversion element to the vertical CCD in FIG.
1. Input 2 consecutive pulses like 32, and always 2 pulses.
The line signal charges are simultaneously transferred to the horizontal CCI).

On the other hand, in the second field following this, a pulse consisting only of pulses like G1.33.34 is input in one horizontal period at the beginning of the field, and only the signal charge from the first line is transmitted in the horizontal direction. In the following horizontal period, two consecutive pulses are input as shown in 35.36, and the signal charges of two lines or [) are simultaneously transferred to the CCD in the horizontal direction.

Then, in the third field, the same operation as in the first field 7 is performed again, and in the fourth field, the same operation as in the 14:@2 field is performed. Thereafter, the operations of the first and second fields are repeated in the same manner.

By performing such a driving method, in the solid-state image sensor shown in FIG.
3. The signal charges of the 4th line, 5th, 6th line, etc. are output simultaneously, and in the second field, only the lth line is output at first, and then 2.3rd line: 4th, 5th line: The signal charges on the 6th and 7th lines can be output at the same time.

Therefore, the line to which the signal charge outputted in the first field belongs and the line where the signal type and load are outputted in the second field are shifted by one column and one column, so a solid-state image sensor with a small number of lines is used. It can be output as an interlaced video signal.

In the following, we have only explained the case where the vertical CCD has two phases, but in the case of three or more phases, only one line of signal charge is transferred to the horizontal CCD at the beginning of the field.
The operation of transferring the signal charges to D and the operation of simultaneously transferring the signal charges of two lines to CC in the horizontal force direction in the next field are as follows.
Alternating rows λ for each field is good.

In addition, in order to prevent the first line signal signal transferred from the light-sound 1 conversion zero unit to the vertical CCD from being transferred into the horizontal CCD, it is necessary to add several clocks to the vertical CCU. S statue of a certain structure In Yonago, is it a traffic signal? After the load is transferred from the photoelectric conversion satin section to the vertical CCI), the number of clock pulses is , an odd number per field.

All you have to do is repeat the even numbers.

In addition, the following is about the toilet line type CCD))-
It is needless to say that this is generally true even in a charge-coupled solid-state imaging device, such as a frame transfer type, which has a vertically oriented CCD in its light receiving section.

〔Effect of the invention〕

As shown in F, according to the present invention, by changing the combination of two lines that are read out simultaneously, interlace operation can be performed on the charge transfer dilatation image device.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a solid-state imaging device using a conventional charge-coupled device, FIG. 2 is a diagram showing the configuration of a two-line simultaneous readout solid-state imaging device to which the present invention is applied, and FIG. 3 is a diagram showing the configuration of a solid-state imaging device using a conventional charge-coupled device. FIG. 3 is a diagram showing an example of a drive pulse waveform according to the invention. φ7. ．． φv2' Direction 'E sending pulse, φ□: Horizontal pulse of television signal, φVQ 'Switch opening/closing 71' pulse, 11, 12. ...IN; Charge transfer CCD, 2: Photoelectric conversion element group, δ: Horizontal Charge transfer CO
D, V, ,: Vertical blanking pulse, 'I'vf,
: Vertical retrace period, T a : 1 field period. Patent applicant: Hitachi Seisakusho Co., Ltd. Patent attorney: Masa Isomura;

Claims (2)

[Claims] (1) A plurality of photoelectric conversion elements arranged two-dimensionally,
The signal charges accumulated in each photoelectric conversion element are transferred in the vertical direction (the signal charges received from the transmission element, the vertical lightning, and the charge transfer element are read out in the horizontal direction in one horizontal period) A solid-state imaging device comprising a charge transfer element and having a structure for simultaneously reading signal charges of two lines, characterized in that the combination of the two lines is changed for each field without reading them simultaneously. How to drive an imaging device. (2) As a method of changing the M field every field, after transferring the signal TIT charge from the photoelectric conversion element to the vertical charge coupled device, the signal TIT charge is transferred to the horizontal return during the first horizontal interval. A field that is transferred one step during the line period,
2. The method of driving a solid-state imaging device according to claim 1, wherein fields are alternately transferred in two stages at a time.