JPS60142681A - Shutter device for electronic camera - Google Patents

Abstract

PURPOSE:To realize a slow shutter speed and to obtain a clear picture if the brightness of an object is low by controlling the drive of an photoelectric conversion image pick up means and prolonging its charge accumulating time. CONSTITUTION:When a shutter switch 6 is truned on, a record timing signal and shutter hold signal generating circuit 15 generates shutter hold signals by synchronizing signals sent from a synchronizing signal generating circuit 4 and shutter signals sent from a shutter switch 6. These shutter hold signals gate the driver output signals sent from a driver 5 by a gate circuit 14, and convert the driver output signals into drive signals of a solid-state image pick up element 2. Control of the drive of the element 2 by such drive signals prolongs its charge accumulating time to form the slow shutter speed.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a shutter device for an electronic camera, and more particularly to a shutter device for an electronic camera that can photograph an object even when the brightness of the subject is low.

[Prior art] Conventionally, there has been a device of this type as shown in FIG.

FIG. 1 is a block diagram of a conventional electronic camera shutter arrangement. In the figure, a lens 1 is provided in front of a solid-state image sensor 2. The solid-state image sensor 2 is connected to a signal processing circuit 3, and the signal processing circuit 3 is connected to a recording system circuit 8. The recording system circuit 8 includes a video signal recording circuit and a clock signal generation circuit (not shown). A lens 1 collects light from a subject, and the collected light is received by a solid-state image sensor 2. The solid-state imaging device 2 photoelectrically converts the received light and outputs an imaging output signal, and the imaging output signal is provided to the signal processing circuit 3. The signal processing circuit 3 converts the imaging output signal and outputs a video signal, and the video signal is given to the recording system circuit 8. A video signal recording circuit of the recording system circuit 8 records a video signal. The synchronizing signal generating circuit 4 is connected to the signal processing circuit 3, the recording system circuit 8, and the driver 5, and the driver 5 is connected to the solid-state image sensor 2. A synchronization signal generation circuit (SSG) 4 generates a synchronization signal, and the synchronization signal is sent to a signal processing circuit 3. It is applied to the recording system circuit 8 and the driver 5.

The driver 5 outputs a solid-state imaging element drive signal, and the solid-state imaging device drive signal is given to the solid-state imaging device 2.

The solid-state image sensor drive signal drives the solid-state image sensor 2.

The shutter switch 6 is connected to a recording timing signal generation circuit 7, and the recording timing signal generation circuit 7 is connected to a recording system circuit 8. The shutter switch 6 generates a shutter signal, and the shutter signal is applied to a recording timing signal generation circuit 7. The clock signal generation circuit of the recording system circuit 8 generates a clock signal, and the clock signal is given to the recording timing signal generation circuit 7. A recording timing signal generation circuit 70 generates a recording timing signal, and the recording timing signal is applied to the recording system circuit 8.

FIG. 2 is a timing chart of the device of FIG.

In the timing chart, (a) is the synchronization signal, (b)
) is the shutter signal, (C) is the recording timing signal, (
d) represents the amount of charge accumulated in the solid-state image sensor.

Next, the operation of this @ position will be explained with reference to FIG. The lens 1 always focuses light from the object onto the solid-state image carrier 2. The synchronization signal generation circuit 4 generates a synchronization signal as shown in (a) of the timing chart, and the driver 5 drives the solid-state image pickup device 2 by this synchronization signal. At this time, the charge layer accumulated in the solid-state image sensor 2 becomes as shown in (d> in the timing chart.The image carrier output signal from the solid-state image sensor 2 is converted into a video signal by the signal processing circuit 3 according to the synchronization signal. When the shutter switch 6 is turned on, the shutter switch 6 generates a shutter signal as shown in timing chart (b).The recording timing signal generation circuit 7 converts the shutter signal from the shutter switch 6 and the recording system circuit 8. The clock signal from the clock signal generation circuit of the timing chart (
A recording timing signal as shown in C) is generated. Only during the time that this signal is rising, the video signal from the signal processing circuit 3 is recorded in the video signal recording circuit of the recording system circuit 8 in accordance with the synchronizing signal.

The shutter device for an electronic camera that uses a conventional video camera to obtain still images is configured as 41I as described above, so the shutter speed is determined by the scanning time of the driver (1/e+
The maximum input amount of the solid-state image sensor 2 is limited by the aperture and aperture of the lens, and if the brightness of the subject is low, it may become impossible to take a picture. Ta.

[Summary of the Invention] This invention was made to eliminate the above-mentioned drawbacks, and therefore, the main purpose of the invention is to provide a shutter device for an electronic camera that can take pictures even when the brightness of the subject is low. It is to provide.

To summarize this invention, the photoelectric conversion imaging means is driven by 1b.
This is a shutter device for an electronic camera that can realize a slow shutter speed by controlling lJ.

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

[Practical Example of the Invention] FIG. 3 is a block diagram of a shutter device for an electronic camera which is an embodiment of the invention. Note that in FIG. 3, the same parts as in FIG. 1 are given the same reference numbers. The block diagram of this device is different from the conventional block diagram of the @-type shown in FIG. - The shutter hold signal generation circuit 15 is used. In the description of the configuration of this device, the description of parts similar to the configuration of the conventional device shown in FIG. 1 will be omitted. The driver 5 is connected to a gate circuit 14, and the gate circuit 14 is connected to the photoelectric conversion m-image means of the solid-state image sensor 2.

The driver 5 outputs a driver output signal, and the driver output signal is given to the gate circuit 14. The gate circuit 14 outputs a solid-state image element drive signal, and the solid-state image drive signal is applied to the solid-state image sensor 2. The solid-state image sensor drive signal drives the solid-state image sensor 2. The synchronization signal generation circuit 4 is connected to a recording timing signal/shutter hold signal generation circuit 15. The recording timing signal/shutter hold signal generation circuit 15 includes a recording timing signal generation circuit and a shutter hold signal generation circuit (not shown). The recording timing signal/shutter hold signal generation circuit 15 is connected to the recording system circuit 8 and the gate circuit 14. A synchronization signal generation circuit 4 generates a synchronization signal, and the synchronization signal is applied to a recording timing signal/shutter hold signal generation circuit 15. A recording timing signal/shuck hold signal generation circuit 15 generates a shutter hold signal, and the shutter hold signal is applied to the gate circuit 14. A gate circuit 14 gates the driver output signal using a shutter hold signal.

FIG. 4 is a timing chart of the device of FIG. 3.

(a) is the synchronization signal, (b) is the shutter signal, <C> is the shutter hold signal, ((1) is the solid-state image sensor drive signal, (0) is the recording timing signal, (f) is the storage in the solid-state image sensor. v4 represents the amount of charge applied.

Next, the operation of this device will be explained with reference to FIG. Note that in the operation of this device, descriptions of parts similar to those of the conventional device shown in FIG. 21 will be omitted as appropriate. When the shutter switch 6 is turned on, the shutter switch 6 generates a shutter signal as shown in (b) of the timing chart.

Recording timing 1/Shutter hold signal generation circuit 1
5 generates a shutter hold M number as shown in (0) in the timing chart using the synchronization signal from the synchronization signal generation circuit 4 and the shutter signal from the shutter switch 6. In response to this shutter bold signal, the driver output signal from the driver 5 is gated by the gate circuit 14 and converted into a solid-state image sensor drive signal as shown in <d') in the timing chart. The amount of charge accumulated in the solid-state image sensor 2 driven by this solid-state image sensor drive signal is as shown in (f) of the timing chart. Therefore, by controlling the drive of the solid-state image sensor 2, the charge accumulation time of the solid-state image sensor 2 can be lengthened, and a slow shutter speed can be realized. That is, in this device, the shutter speed is increased by the amount held by the shutter hold signal from the conventional fixed driver scanning time. Furthermore, it is natural that the shutter speed can be changed by changing this hold time. Further, the recording timing signal/shutter hold signal generation circuit 15 receives the shutter signal from the shutter switch 6 and the recording thread circuit 8.
In response to the clock signal from the clock signal generating circuit J:, a recording timing signal as shown in <e> of the timing chart is generated, and the recording system circuit 8 is operated by this recording timing signal and synchronization signal.

[Effects of the Invention] As described above, according to the present invention, since the drive of the photoelectric conversion imaging means can be controlled, the charge accumulation time of the charging conversion Wi imaging means can be lengthened, and the slow A shutter switch can be realized. Therefore, in the electronic camera, even if the brightness of the subject is low, it is possible to take a photograph that provides a clear image.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional electronic camera shutter device. FIG. 2 is a timing chart of II in FIG. 10- FIG. 3 is a block diagram of a shutter device for an electronic camera which is an embodiment of the present invention. FIG. 4 is a timing chart of the device of FIG. 3. In the figure, 1 is a lens, 2 is a solid-state image carrier, 3 is a signal processing circuit, 4 is a synchronization signal generation circuit, 5 is a driver, 6 is a shutter switch, 8 is a recording system circuit, 14 is a gate circuit, and 15 is a recording This is a timing signal/shutter hold signal generation circuit. Agent Masuo Oiwa 11-

Claims (1)

[Scope of Claims] Photoelectric conversion imaging means for photoelectrically converting received light and outputting an imaging output signal; synchronization signal generation means for generating a synchronization signal; and a synchronization signal generation means for generating the imaging output signal in response to the synchronization signal. a signal processing means for converting into a video signal and outputting the video signal; a driving means for generating a drive output signal for driving the photoelectric conversion ms means in response to the synchronization signal; and a shutter switch for generating a shutter signal. , a recording system circuit including a video signal recording circuit that records the video signal and a clock signal generation circuit that generates a clock signal; a recording system circuit that generates a recording timing signal in response to the shutter signal and the clock signal; a recording timing signal/shutter hold signal generation circuit that generates a shutter hold signal in response to the synchronization signal and the shutter signal;
and a gate means for recording the video signal in response to the recording timing signal, gating the drive output signal according to the shutter hold signal, and driving the photoelectric conversion imaging means.