JPH0257074A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To form a reproduced picture with sense of speed and less blur from a fast moving object by driving a solid-state image pickup element at a speed being an integral number of multiple of the substantial speed, allocating a light intake time of a photo sensor several times in a substantial field period and extracting a video signal. CONSTITUTION:A drive circuit 21 for a solid-state image pickup element drives the solid-state image pickup element 11 at a frequency being twice the standard timing frequency of a television signal by means of the electronic shutter. Thus, video signals twice conventional signals are obtained as shown in figure (b). The video signal is outputted as a video signal via a low pass filter 41, a preamplifier 51 and a process circuit 61 and the signal is recorded in a recording reproducing section 71 of the video signal. When the video signal is subject to slow reproduction, since the video signals twice the conventional signals are recorded and stored, a sharp dynamic video image with sense of speed and less blur is obtained from a fast moving object together with the operation of the electronic shutter.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a solid-state imaging device using an electronic shutter system used in a television camera or the like, and particularly to an imaging/reproducing method when using the electronic shutter system.

[Conventional technology]

FIG. 3 shows a block diagram of an interline COD solid-state image sensor, which is an example of a solid-state image sensor capable of electronic shutter operation, and FIG. 4 shows a block diagram of an example of a solid-state image sensor.

In FIG. 3, light incident on a plurality of photosensors 1 forms signal charges in the potential wells of the photosensors 1 according to the amount of light, and is read out all at once to the vertical shift register 2 by a readout pulse. The entire charge pattern of the vertical shift register 2 is transferred row by row to the horizontal shift register 3 in parallel for each horizontal scanning line, and is sequentially output from the output circuit section 4 as a video signal.

In FIG. 4, the video signal output from the solid-state image sensor 11 is passed through a reduction filter 42 and a preamplifier 52 to a process circuit 62 for signal processing such as shading correction, aperture correction, flanking pulse mixing, and γ correction. is performed and output as a video signal.

Furthermore, when using the electronic shutter system, signal charges of unnecessary video signals accumulated in the photosensor 1 are removed by unnecessary charge readout pulses during the vertical blanking period.
A sweep train 5 is read out to the vertical shift register 2 and is operated at high speed by a high-speed sweep pulse having a frequency 50 to 100 times faster than a normal clock pulse. After a certain daylighting time has elapsed, the signal charge of the video signal that has been removed is read out from the photosensor 1 to the vertical shift register 2 by a readout pulse, and then sequentially output as a video signal by the same operation as described above.

[Problem to be solved by the invention]

The above-mentioned conventional solid-state imaging device is compatible with the standard television system and captures images for a certain period of time (for example) within one field period.
, / 1000 sec, 1/2000 sec, etc.) to collect the video signal by allocating the lighting time of the photosensor, making the video signal charges collected during other periods unnecessary,
Especially for fast-moving subjects,
If a clear image with less blurring is obtained, or if slow playback is performed, the playback image has the disadvantage that the playback image lacks the fluidity of a single still image.

SUMMARY OF THE INVENTION An object of the present invention is to provide a solid-state imaging device that can provide a clear reproduced image with a sense of fluidity and less blur when an image of a fast-moving object is captured using an electronic shutter operation and reproduced in slow motion.

[Means to solve the problem]

The solid-state imaging device of the present invention includes a solid-state imaging device capable of operating an electronic shutter, a drive circuit that drives the solid-state imaging device at an integral multiple of a standard method and generates a drive pulse to operate the electronic shutter, and the solid-state imaging device. a process circuit that receives the output signal of the element via a low-pass filter and a preamplifier; a select logic that selects only a video signal that meets a standard format from the output of the process circuit; and a select logic that receives the output signal of the process circuit. It includes a recording and reproducing section that performs recording and slow reproduction.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIGS. 2(a) and 2(b) show the conventional example and the present example when a video signal collected by electronic shutter operation is played back in slow motion. FIG. 2 is a conceptual diagram for comparing cases.

As shown in FIG. 1, this embodiment uses a solid-state image sensor 11 capable of electronic shutter operation and a drive pulse that drives the solid-state image sensor 11 at twice the speed of the standard system to operate the electronic shutter. A generation drive circuit 21, a synchronous pulse generator 31, a reduction filter 41, a preamplifier 51, and a process circuit 6 that performs signal processing such as shape ink correction, aperture correction, blanking pulse mixing, and γ correction. ] and controlled by the synchronization pulse of the synchronization pulse generator 31,
By using the select logic 81 to select and output only video signals that meet the standard television system and an electronic shutter system, the playback is clear and fluid with less blurring and no frame-by-frame playback when slow playback is performed. In order to obtain an image, the video signal recording/reproducing section 7 is capable of recording and reproducing one screen's worth of video signals in addition to one screen's worth of video signals of the Telehijo standard system.

By driving the solid-state image sensor 11 with an electronic shutter operation at a frequency twice the standard timing frequency of the television by the solid-state image sensor drive circuit 2 in FIG. In this way, twice as much video signal as before can be obtained. These video signals are passed through a reduction filter 4
1. The signal is output as a video signal via the preamplifier 51 and the process circuit 61, and is recorded in the video signal recording/reproducing section 71. When these video signals are played back in slow motion, as shown in Figure 2, twice as many video signals as before are recorded and accumulated, so the played video is slowed down by the electronic shutter operation. For fast-moving subjects, you can obtain clear, dynamic images with a sense of fluidity and less blur.

In addition, when outputting a video signal that is not normally recorded or played back,
In FIG. 1, by controlling the select logic 81 to selectively output only the video signal compatible with the standard television format using the timing pulse of the synchronization pulse generator 31, one screen indicated by the broken line in FIG. It is possible to remove the video signal 7 and output the video signal. The output of the selection logic is input to the image receiving apparatus as a standard format video signal by a format conversion device (not shown) including three field memories. Since signals are removed from each field in advance, writing to the field memory can be performed reliably and good images can be obtained.

In this example, the solid-state image sensor is driven at twice the speed of the conventional image sensor, and twice as much video signal as the conventional one is collected and recorded. We have described a solid-state imaging device that can provide a sense of fluidity during slow playback by driving at several times the speed allowed by the solid-state imaging device and collecting and recording several times as many video signals. Needless to say, dynamic reproduced images can be obtained.

Although an interline CCD was used as the solid-state image sensor, it goes without saying that the present invention can be applied to other types of solid-state image sensors as long as they are capable of electronic shutter operation.

〔Effect of the invention〕

As explained above, the present invention drives the solid-state image sensor at an integer multiple of the original speed, allocates several degrees of light exposure time to the sensor within the original one field period, and collects the video signal. This makes it possible to provide clear playback images with a sense of fluidity and less blurring, even when performing slow playback of a video signal recorded using an electronic shutter system for a fast-moving subject. effective.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG.
a) and (b) are conceptual diagrams for comparing the case of the conventional example and the case of this embodiment when video signals collected by electronic shutter operation are played back in slow motion. FIG. 4 is an example of a block diagram of a conventional solid-state imaging device. 1...Photo sensor, 2...Vertical register, 3...
・Horizontal shift register, 4... Output circuit section, 5...
Sweep drain, 6...1 screen worth of video signal, 7.
... Video signal for one screen newly added according to the present invention, 11... Solid-state image sensor, 21.22... Drive circuit section, 32.32... Synchronization pulse generator, 41.42.
... Reduction filter, 51.52 ... Preamplifier, 61.
62...Process circuit, 71.72...Video signal recording/reproducing unit, 81...Select logic, 91.92
...Video signal recording/playback control circuit.

Claims (1)

[Claims] a solid-state image sensor capable of electronic shutter operation; a drive circuit that drives the solid-state image sensor at an integer multiple of a standard speed and generates a drive pulse to operate the electronic shutter; A process circuit that receives the signal through a filter and a preamplifier, a select logic that selects only a video signal compatible with a standard format from the output of the process circuit, and a record that receives and records the output signal of the process circuit and performs slow playback. A solid-state imaging device comprising: a reproduction section.