JPH09130819A - Solid-state image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize an image processor without using a frame memory of a digital system in order to detect moving information of an image from the image pickup output signal of a solid-state image pickup device. SOLUTION: This device consists of plural sheets of CCD solid-state image pickup plates 3 to 6. Then when a FIT-type CCD solid-state image pickup plate is used for each of the CCD solid-state image pickup plates, concerning one sheet of solid-state image pickup plate 5 among the plural sheets, the driving timing of a driving signal for driving the solid-state image pickup plate is made different from the driving timing of a driving signal for driving the other solid- state image pickup plates 3 to 5 to fetch a difference signal mutually between the respective image pickup output signals of the one sheet of solid-state image pickup plate 5 and one sheet of solid-state image pickup plate 4 among before- mentioned the other solid-state image pickup plates both of which are driven with mutually different driving timings as moving information of image picked-up image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state image pickup device comprising a plurality of CCD solid-state image pickup plates, and in particular, it is possible to output motion information of a picked-up image in addition to an image pickup output signal. To do.

[0002]

2. Description of the Related Art Generally, in order to detect motion information of an image (motion detection), it is necessary to obtain a difference between images captured at different times. A moving image capturing device such as a television camera normally outputs 60 field image signals per second. In order to perform differential processing of this image signal between before and after the field, a memory for storing the image signal for one field is required.

If this memory is realized in the analog domain and an image signal for one field is to be stored, a storage means such as a VTR is required, but this makes it difficult to perform difference processing in real time. Therefore, in the conventional technique, a plurality of continuous image signals obtained from the moving image pickup device are A / D converted into digital signals, which are then stored in a plurality of field memories (digital memory). Motion information is detected by performing difference processing between image signals stored in the memory and captured at different times.

[0004]

However, in order to detect motion information of an image using a plurality of digital field memories as described above, first, an image signal is converted into a digital signal by an A / D converter. It is necessary to perform processing to store the image signal in a digital field memory, such as when the image signal is converted into a high-definition image such as a high-definition circuit. This leads to an increase in scale and power consumption.

[0005]

As described above, the conventional image motion detection is performed outside the television camera, that is, in the image signal processing system that processes the image pickup output signal. In addition, it required a digital field memory. In contrast, the present invention is based on the frame interline transfer (F
IT) type CCD solid-state image pickup plate (usually referred to as FIT type CCD image pickup element, for example, Matsumoto et al., "Smear and its reduction structure in interline transfer type CCD", IEICE Tech. ED82-11.pp.27- 32 (May, 1982)
And Horii et al. “New CCD image sensor” Sho 56 Shin-Gaku Semi-conductor 135. p. 136 (see 1981)), a solid-state image pickup device has a charge accumulation unit for accumulating charges read from a photoelectric conversion unit for one field as an analog signal in a solid-state imaging plate. Therefore, a CCD solid-state image pickup plate (for example, FIT CCD solid-state image pickup plate) having a charge storage unit and a CCD solid-state image pickup plate (for example, IT-type CCD solid-state image pickup plate) not having the charge storage unit are mixed in the solid-state image pickup device, By delaying the image pickup output signal from the CCD solid-state image pickup plate having a charge storage portion by one field, or as described in detail in the following embodiments,
A plurality of CCD solid-state imaging plates (for example, F
An IT type CCD solid-state image pickup plate) is used to configure a solid-state image pickup device, and the timing of charge transfer to the charge storage section (driving timing of the solid-state image pickup plate) is made different among a plurality of solid-state image pickup plates, thereby making it possible to use a conventional digital image pickup device. This is based on the idea that the motion detection of an image, which was performed using the method field memory, can be performed in the analog area.

Based on this idea, the solid-state image pickup device of the present invention is a solid-state image pickup device comprising a plurality of solid-state image pickup plates, and a CCD solid-state image pickup plate having a charge storage portion and a CCD solid-state image pickup plate not having the same. , And the imaging output signals that are shifted from each other by one field period are taken out from each other, or, if they are composed of a plurality of CCD solid-state imaging plates having a charge accumulating portion, one of those solid-state imaging plates is present. By shifting the drive timing of the solid-state image pickup plate from the drive timing of the other solid-state image pickup plate for one field period, the image pickup output signals imaged at the time points separated by one field period from each other in the solid-state image pickup device were simultaneously obtained. By taking the difference signal between the image pickup output signals, it is possible to detect the motion information of the picked-up image.

That is, the solid-state image pickup device of the present invention is a solid-state image pickup device comprising a plurality of CCD solid-state image pickup plates, wherein the solid-state image pickup device is at least one of the plurality of solid-state image pickup plates. The solid-state image pickup plate has a storage unit for storing at least one field of charges of all pixels photoelectrically converted by the photoelectric conversion element arranged in the light receiving unit, and the storage unit stores the charges of all the pixels for one field period. Each of the plurality of lines is sequentially transferred and accumulated therein, and the accumulated charge of one field before accumulated in the accumulator is transferred to the horizontal charge transfer means and sequentially read out pixel by pixel. A plurality of solid-state image pickup plates other than the at least one solid-state image pickup plate out of the single solid-state image pickup plates receive a charge of all pixels photoelectrically converted by the photoelectric conversion element arranged in the light receiving portion. One solid-state image pickup plate of the at least one solid-state image pickup plate and the at least one solid-state image pickup plate are configured to be sequentially read out line by line and sequentially read out for each pixel in a read period. The difference signal between the image pickup output signals of one solid-state image pickup plate among the plurality of solid-state image pickup plates except the one is configured to be extracted as motion information of the image pickup pixel. is there.

In the solid-state image pickup device of the present invention, the plurality of solid-state image pickup plates are two solid-state image pickup plates for green light, and one solid-state image pickup plate for green light.
Consisting of one solid-state image pickup plate for blue light and red light, one solid-state image pickup plate of the at least one solid-state image pickup plate is one of the two solid-state image pickup plates for green light, One of the plurality of solid-state image pickup plates except the at least one solid-state image pickup plate is another one of the two solid-state image pickup plates for green light, and the difference signal Is configured to be taken out from between the respective image pickup output signals of the two solid-state image pickup plates for green light.

The solid-state image pickup device of the present invention includes two solid-state image pickup plates for green light, and one solid-state image pickup plate for red light and one solid-state image pickup plate for blue light, each having a frame interline transfer type CCD solid-state image pickup plate. The solid-state image pickup device is configured using the solid-state image pickup device for green light, blue light, and red light, and the accumulated charge of all pixels is accumulated through the vertical charge transfer CCD in the vertical blanking period. The accumulated electric charge of the field concerned is read out during the video effective period of the next field, and the output corresponding to the solid-state image pickup plate for green light is output from the read output signal. The signal is the first imaging output signal,
With respect to the remaining one solid-state image pickup plate for green light, all the pixels transfer the accumulated charge to the vertical charge transfer CCD during the vertical blanking period, and the one field accumulated in the accumulation unit during the image effective period of the next field. While reading the previous accumulated charge as the second image pickup output signal, the accumulated charge for one line is transferred and accumulated from the vertical charge transfer CCD to the accumulation unit for each horizontal blanking period within the video effective period, The difference signal between the first and second image pickup output signals is extracted as motion information of a picked-up image.

Further, the solid-state image pickup device of the present invention is of a three-plate type so that when the motion information of the picked-up image is not necessary, an image pickup output signal without a time difference can be obtained from both of the two solid-state image pickup plates for green light. It is characterized in that it comprises a switching means for switching to a four-plate imaging system.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments with reference to the accompanying drawings. FIG. 1 is a block diagram showing the configuration of the solid-state imaging device of the present invention. In FIG. 1, the structure is the same as that of a so-called four-plate type color solid-state imaging device except for electronic circuits denoted by reference numeral 7 and below. Therefore, the present apparatus can be configured to switch and use the normal four-plate imaging mode when it is not necessary to detect the motion information of the image.

As is well known, the part of the four-plate type color solid-state image pickup device (the part indicated by reference numeral 6) is an image pickup lens 1 for forming an optical image, a four-plate type image-pickup photolytic prism 2, and a blue light. CCD solid-state image pickup plate (hereinafter, simply CC
D) 3, CCD 4 for green light I, CCD for green light II
5 and CCD 6 for red light. However, what is important in the present invention is the CCD for green light II.
The drive timing of the drive signal of No. 5 is set to other color light CCDs 3,
Although different from those of 4 and 6, this will be described in detail later with reference to the waveform diagram of the drive signal.

Here, a CCD having a field memory is used for all, and a CCD 5 for green light II is used among them.
Is different from the driving timing (C
(The same drive timing for CD3, 4 and 6)
It is assumed that the image pickup output signal delayed by one field from the image pickup image signal from the CCD 4 is obtained from the CCD 5 by being driven by. The image pickup output signals of the CCDs 3, 4 and 6 are passed through the preamplifiers 7, 8 and 10 to the B
Image pickup output signals of three primary colors of (blue), G (green) and R (red) are obtained.

On the other hand, the image pickup output signal of the CCD 5 is guided to the subtractor 11 (the subtractive terminal or the subtrahend terminal) via the preamplifier 9, and the output signal of the preamplifier 8 is also subtracted.
It is possible to extract the change (motion component signal) from the output terminal of the subtracter 11 for each imaging output signal which is delayed by one field from the output terminal of the subtractor 11 by leading to 1 (reducible terminal or subtractive terminal).

Prior to describing the method of driving the solid-state image pickup plate used in the present invention (the ordinary driving method and the driving method required to achieve the present invention), the CCD used in the solid-state image pickup device of the present invention will be described. An example of the configuration is shown and its operation will be described. FIG. 2 shows a frame interline transfer (FI) used in the solid-state imaging device of the present invention.
The structure of an example of a T) type CCD is shown. As shown in the figure, this type of CCD has a light receiving section 12 for receiving an optical image,
A photodiode 13 for each pixel arranged in the light receiving unit 12, a storage unit 14 that stores charges photoelectrically converted by these photodiodes, a vertical charge transfer CCD 15 that transfers the charges in the vertical direction, and a charge that transfers the charges in the horizontal direction. It is composed of a horizontal charge transfer CCD 16 and an output amplifier 17. The charges photoelectrically converted by the photodiode 13 are transferred along the path indicated by the arrow in the figure, and the image pickup output signal is output from the output terminal 18.

FIG. 3 shows the driving timing of the CCD necessary for realizing the solid-state image pickup device of the present invention. FIG.
2A shows drive timings of drive signals for driving the CCDs 3, 4 and 6, and FIG. 8B shows drive timings of drive signals for driving the CCD 5. Here, the type of drive signal (drive pulse) is set to the minimum necessary for characterizing the present invention, the vertical blanking signal l,
Charge read pulse m, vertical charge transfer pulse n, vertical −
Only the horizontal charge transfer pulse o, its enlarged view p, and the horizontal charge transfer pulse q are shown.

First, with the drive signal (a), charges are transferred from the photodiode 13 to the vertical charge transfer CCD 15 (see FIG. 2; the same applies hereinafter) by the charge read pulse m within the vertical blanking period. Further, the vertical charge transfer pulse n transfers all the charges of the light receiving unit 12 to the storage unit 14. Vertical to horizontal blanking period during video valid period −
By the horizontal charge transfer pulse o (enlarged view p), the storage unit 1
The charge for one line stored in 4 is a horizontal charge transfer CCD
16, the charge transferred from the horizontal charge transfer CCD 16 is read by the horizontal charge transfer pulse q, and the imaging output signal is output from the output terminal 18 via the output amplifier 17.

Next, the drive signal (b) is the same as that of the drive signal (a) up to the point where charges are transferred to the vertical charge transfer CCD 15 by the charge read pulse m. However, after that, as in the case of the drive signal (a), all the charges are not transferred to the storage unit during the vertical blanking period, and the vertical charge transfer pulse n causes the charges to be transferred one stage (one line) at a time during the video effective period. Is transferred to the storage unit. In this way, the charge passing through the light receiving unit 12 and the storage unit 14 is 1
Each line is transferred to the horizontal charge transfer CCD 16 by the vertical-horizontal charge transfer pulse o (its enlarged view p), and the transferred charge is read by the horizontal charge transfer pulse q,
An imaging output signal is output from the output terminal 18 via the output amplifier 17.

The image pickup output signal of the CCD 5 (green light II CCD) driven by the drive signal (b) described above is output one field later than the image pickup output signals of the other CCDs driven by the drive signal (a). To be done. Therefore, if subtraction is performed between the green light image pickup output signals having this relationship, only the motion component signal (field difference signal) is output.

In the embodiment described above, all the CCDs to be used are made up of FIT type solid-state image pickup plates, and the driving timing of one of the CCDs is shifted from the driving timing of the other one field period. For each of the solid-state image pickup plates for green light, blue light, and red light, the accumulated charges of all pixels are transferred to and accumulated in the accumulation unit via the vertical charge transfer CCD during the vertical blanking period. The accumulated charge of the field concerned is read out during the video valid period of the next field, and the output signal corresponding to the solid-state image pickup plate for green light among the read output signals is the first image pickup output signal. In the remaining one solid-state image pickup plate for green light, all the pixels transfer the accumulated charge to the vertical charge transfer CCD during the vertical blanking period.
During the video effective period of the next field, the accumulated charge of one field before stored in the accumulating unit is read as the second imaging output signal, and the accumulated charge of one line is obtained for each horizontal blanking period within the image effective period. Is configured to be transferred and accumulated from the vertical charge transfer CCD to the accumulator, and a difference signal between the first and second image pickup output signals is taken out as motion information of a picked-up image. Alternatively, the configuration may be changed as follows.

That is, in another embodiment of the present invention, at least one solid-state image pickup plate among a plurality of solid-state image pickup plates constituting the solid-state image pickup device is photoelectrically converted by the photoelectric conversion element arranged in the light receiving section. A storage unit for storing the charges of all pixels to be converted for at least one field is provided, and the charges of all the pixels are sequentially transferred to and stored in the storage unit for one line in one field period. Is configured to transfer the accumulated charge of one field before stored in the unit to the horizontal charge transfer means and sequentially read it for each pixel, and the at least one solid-state image pickup plate among the plurality of solid-state image pickup plates A plurality of solid-state image pickup plates except for transfer the charges of all the pixels photoelectrically converted by the photoelectric conversion element arranged in the light receiving section one line by one line within one field period, and One solid-state image pickup plate of the at least one solid-state image pickup plate and one solid-state image pickup of the plurality of solid-state image pickup plates excluding the at least one solid-state image pickup plate A difference signal between the image pickup output signals of the plate may be extracted as motion information of the image pickup pixel.

In the embodiment described with reference to FIGS. 1 to 3, as described at the beginning of the embodiment,
When it is not necessary to extract the motion information, the same drive pulse is applied to the CCDs 3 to 6 through the switching means, that is, the drive signal (a) in FIG. 3 (or the drive signal (b) in FIG. 3).
Can be operated in a four-plate imaging mode. In the configuration for detecting the motion information, the image pickup output signal is obtained only from the CCDs 3, 4 and 6, and therefore, the three-plate type image pickup mode is selected. The same applies to the other embodiments described above.

[0023]

According to the present invention, since the motion component signal (field difference signal) can be formed inside the solid-state image pickup device without using a digital frame memory or the like, it is possible to form the motion component signal as in the conventional case. It is not necessary to detect the motion information by digitally processing the image pickup output signal taken out from the solid-state image pickup device. Therefore, the motion detection unit can be omitted from the image processing device, and the size and weight of the image processing device can be reduced. It can contribute to the ripple effect.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a solid-state imaging device according to the present invention.

FIG. 2 shows a configuration of an example of a CCD used in the solid-state imaging device of the present invention.

FIG. 3 is a C necessary for realizing the solid-state imaging device of the present invention.
The drive timing of CD is shown.

[Explanation of symbols]

 1 Imaging Lens 2 4 Plate Type Photolytic Prism 3 CCD for Blue Light 4 CCD for Green Light I 5 CCD for Green Light II 6 CCD for Red Light 7, 8, 9, 10 Preamplifier 11 Subtractor 12 Photoreceptor 13 Photodiode 14 Storage unit 15 Vertical charge transfer CCD 16 Horizontal charge transfer CCD 17 Output amplifier 18 Output terminal l Vertical blanking signal m Charge read pulse n Vertical charge transfer pulse o Vertical-horizontal charge transfer pulse p Vertical-horizontal charge transfer pulse ( Enlarged view) q Horizontal charge transfer pulse

Claims (4)

[Claims] 1. A solid-state image pickup device comprising a plurality of CCD solid-state image pickup plates, wherein at least one of the plurality of solid-state image pickup plates has a light receiving section. Has a storage unit for storing the electric charges of all pixels photoelectrically converted by the photoelectric conversion element arranged in 1 field, and the electric charges of all the pixels are sequentially stored in the storage unit for one line within one field period. While being transferred and accumulated, the accumulated charge of one field before accumulated in the accumulator is transferred to the horizontal charge transfer means and sequentially read out pixel by pixel. Of the plurality of solid-state image pickup plates except the at least one solid-state image pickup plate, the charges of all the pixels photoelectrically converted by the photoelectric conversion element arranged in the light receiving portion are sequentially arranged for one line in one field period. Of the plurality of solid-state image pickup plates excluding the at least one solid-state image pickup plate and the at least one solid-state image pickup plate. A solid-state image pickup device, characterized in that a difference signal between image pickup output signals of one of the solid-state image pickup plates is extracted as motion information of an image pickup pixel. 2. The solid-state imaging device according to claim 1, wherein the plurality of solid-state imaging plates are two solid-state imaging plates for green light,
And each of the solid-state image pickup plates for blue light and red light, one solid-state image pickup plate of the at least one solid-state image pickup plate is one of the two solid-state image pickup plates for green light. And one solid-state image pickup plate of the plurality of solid-state image pickup plates excluding the at least one solid-state image pickup plate is another one of the two solid-state image pickup plates for green light, The solid-state image pickup device according to claim 1, wherein the difference signal is extracted from between the image pickup output signals of the two solid-state image pickup plates for green light. 3. Two solid-state image pickup plates for green light, and one each
A solid-state image pickup device is constructed by using a frame interline transfer type CCD solid-state image pickup plate for each of the solid-state image pickup plates for red light and blue light, and one solid-state image pickup plate for green light, blue light, and red light. Regarding the image pickup plate, the accumulated charges of all pixels are transferred to and accumulated in the accumulation section through the vertical charge transfer CCD during the vertical blanking period, and the accumulated charges of the field concerned are accumulated during the image effective period of the next field. The output signal corresponding to the solid-state image pickup plate for green light among the read output signals is set as the first image pickup output signal, and the remaining one solid-state image pickup plate for green light is The accumulated charges of all pixels are transferred to the vertical charge transfer CCD during the blanking period, and the accumulated charges of one field before accumulated in the accumulation unit are accumulated during the video effective period of the next field. While reading out as the second image pickup output signal, the accumulated charges for one line are transferred and accumulated from the vertical charge transfer CCD to the accumulating unit for each horizontal blanking period within the video effective period. The solid-state image pickup device is configured so that a difference signal between the image pickup output signals of 1 is extracted as motion information of a pickup image. 4. The solid-state imaging device according to claim 2, wherein when the motion information of the captured image is not needed, the 2
A solid-state image pickup device comprising switching means for switching from a three-plate type to a four-plate type image pickup system so that an image pickup output signal having no time difference can be obtained from both of the solid-state image pickup plates for green light.