JPH0666919B2 - Video camera equipment - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video camera device using a solid-state image sensor.

2. Description of the Related Art In recent years, special playback such as low-speed playback, frame advance, and still image has been actively performed in VCRs. For this reason, high-speed video cameras, which reduce the blurring of moving image subjects during special playback, are drawing attention as video cameras.

Hereinafter, an example of the above-described conventional high-speed video camera will be described with reference to the drawings.

FIG. 3 is a block diagram showing the overall structure of a high-speed video camera using a conventional interline charge-coupled solid-state imaging device (hereinafter abbreviated as IL-CCD).

14 is an optical lens, 15 is an IL-CCD, 16 is a signal processing unit that converts the signal output from 15 into a television signal, and 17 is 15
Is a driving unit, and 18 is a signal processing pulse generation circuit for generating a signal used in 16.

The operation of the high-speed video camera using the conventional IL-CCD configured as above will be described below.

First, the optical signal incident through 14 optical lenses
It is stored in the IL-CCD, and the storage time is controlled by a signal generated from the drive unit of 17 and converted into an electric signal. afterwards
The 16 signal processing units convert the signals generated by the 18 signal processing pulse generation circuits into television signals.

The configuration and operation of the IL-CCD will be described below with reference to FIGS. In FIG. 4, reference numeral 19 denotes a photodiode 20 as a photoelectric conversion element which is a vertical transfer register, and this vertical transfer register is composed of vertical transfer gates 21, 22, 23 and 24. Reference numeral 25 is a signal read gate, which is equivalently shared with the vertical transfer gates 21 and 23. 26 is a vertical transfer pulse supply terminal. Reference numeral 27 denotes a horizontal transfer register, which is composed of horizontal transfer gates 28 and 29. Reference numeral 30 is a horizontal transfer pulse supply terminal. Reference numeral 31 is a charge detection unit, which converts the transferred signal charge into a signal voltage. The charge detection unit 31 is normally a floating diffusion amplifier (Floating Diffusion Ampli
fier). 32 is a signal output terminal.

The photodiode 19 photoelectrically converts incident light from a subject to obtain a signal charge. The signal charges obtained by photoelectric conversion are read into the vertical transfer gates constituting the vertical transfer register 20 via the signal readout gate 25, and then by the vertical transfer pulse supplied from the vertical transfer pulse supply terminal 26,
The data is sequentially transferred in the vertical direction, that is, in the direction of the horizontal register 27, and is read into the horizontal transfer register 27 for each horizontal line. The signal charges read into the horizontal transfer register are sequentially transferred to the charge detection unit 31 on the horizontal transfer pulse supplied from the horizontal transfer pulse supply terminal 30, converted into a voltage by the charge detection unit 31, and output from the signal output terminal 32. It is obtained as a dot-sequential signal. A television signal is obtained by passing the dot-sequential signal obtained by the above-described method through the signal processing unit 16 shown in FIG.

FIG. 5 is a timing chart of the vertical transfer pulse supplied to the vertical transfer pulse supply terminal of the IL-CCD, and FIG.
A part of the timing chart of the signal output from FIG. 18 is shown, and the description will be given below.

Reference numerals 33 and 34 denote a first read signal and a second read signal, respectively, for reading signal charges from the photoelectric conversion element to the vertical transfer register, and 35 is read to the vertical transfer register by the first read signal. A high-speed vertical transfer signal that sequentially transfers signal charges to the horizontal transfer register at high speed.
Reference numeral 36 is a vertical transfer signal for sequentially transferring the signal charges read by the second transfer signal to the vertical transfer register to the horizontal transfer register. 37 is a clamp signal for fixing the optical dark part of the signal output from the output terminal of the IL-CCD to an arbitrary potential.

The signal charge accumulated in the photoelectric conversion element between the first read signal 33 of the first field and the second read signal 34 of the first field is the television signal of the first field based on the operation of the IL-CCD. Therefore, the signal charge accumulated in the photoelectric conversion element between the second read signal 34 of the first field and the first read signal 33 of the second field is transferred at high speed to the horizontal transfer register by the high speed vertical transfer signal 35. It is swept out within the vertical blanking period of the second field. The signal charge accumulated in the photoelectric conversion element between the first read signal 33 of the second field and the second read signal 34 of the second field is the second based on the operation of the IL-CCD.
It becomes a television signal in the field. The signal charge accumulated between the second read signal 34 of the second field and the first read signal 33 of the first field is transferred at high speed to the horizontal transfer register by the high speed vertical transfer signal 35, and Swept out within the vertical blanking period.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the high-speed video camera device using the IL-CCD, the signal charge swept out in the vertical blanking period overflows into the optical dark part, and the vertical blanking period and the vertical scanning period. The clamp potential is different depending on the condition, and there is a drawback that a clamp error is made in the upper part of the image and the screen is adversely affected.

In view of the above problems, the present invention provides a video camera device capable of high-speed shooting in which a means for stopping a clamp signal while sweeping out a signal charge is provided to eliminate a clamp error at the top of the screen.

Means for Solving the Problems In order to solve the above problems, the present invention provides a solid-state imaging device that is provided with means for stopping the clamp signal for an arbitrary period between the first read signal and the second read signal. It is provided with a configuration having an element drive circuit.

Operation The present invention can eliminate the clamp error at the upper part of the screen, which significantly deteriorates the image quality.

Embodiment A video camera device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block diagram of the overall configuration of the first embodiment of the present invention. In FIG. 1, 1 is an optical lens, 2
Is an IL-CCD, 3 is a signal processing unit, 4 is a solid-state image sensor drive circuit for driving 2, 5 is a solid-state image sensor vertical drive circuit which is one component of 4, and 6 is a clamp signal control which is one component of 4. Reference numeral 7 denotes a signal processing pulse generating circuit for generating a signal used in 3.

The operation of the high-speed video camera using the IL-CCD configured as described above will be described below with reference to FIGS. 1 and 2.

First, FIG. 2 is a timing chart of a vertical pulse supplied to the vertical pulse supply terminal of the IL-CCD, a clamp signal stop signal generated by the clamp signal control unit, and a clamp signal generated by the signal processing pulse generation circuit. Is.

Signal 8 in FIG. 2 is signal 36 in FIG. 5, signal 9 is signal 33 in FIG.
10 is the same as 34, and signal 11 is the same as 35.

During the period from the first read signal 9 of the first field to the second read signal 10 of the first field, the signal charge accumulated in the photoelectric conversion element of the IL-CCD is changed based on the operation of the IL-CCD. It becomes a television signal of 1 field,
During the period from the second read signal 10 of the first field to the first read signal 9 of the second field, the signal charge accumulated in the photoelectric conversion element of the IL-CCD is transferred to the horizontal transfer register at high speed by the high speed vertical transfer signal 11. It is transferred and swept out within the vertical blanking interval of the second field. The signal charge accumulated in the photoelectric conversion element of the IL-CCD between the first read signal 9 of the second field and the second read signal 10 of the second field is changed to the second charge based on the operation of the IL-CCD. It becomes a television signal in the field. The signal charge accumulated in the photoelectric conversion element of the IL-CCD between the second read signal 10 of the second field and the first read signal 9 of the first field is transferred to the horizontal transfer register by the high speed vertical transfer signal 11. It is transferred at high speed and is swept out in the vertical blanking period of the first field.

The clamp signal stop signal 12 has the potential Va during an arbitrary period from the first read signal 9 to the second read signal 10 and has the potential Vb (Va> Vb) during the other periods. Due to the clamp signal stop signal 12, the clamp signal 13 does not occur during the period when the clamp signal stop signal is at the potential Va, and is generated only during the period when the potential is Vb.

As described above, according to the present embodiment, by providing the clamp signal control unit that stops the clamp signal for an arbitrary period between the first read signal and the second read signal, the clamp is dislocated at the upper part of the screen. A high-speed video camera device having good characteristics can be provided.

In the first embodiment, 2 in FIG. 1 is an IL-CCD, but the same applies to a frame transfer charge coupled type solid-state imaging device.

EFFECTS OF THE INVENTION As described above, according to the present invention, the clamp signal control unit for stopping the clamp signal for an arbitrary period of the storage time of the signal charge that becomes the television signal is provided, so that the upper portion of the screen that deteriorates the image quality is provided. The clamp can be removed from the clamp and its effect is great.

[Brief description of drawings]

FIG. 1 is a block diagram of the overall configuration of the first embodiment of the present invention, FIG. 2 is a timing chart of signals of respective parts in FIG. 1, and FIG. 3 is a video camera device using a conventional IL-CCD. FIG. 4 is a block diagram of the overall configuration, FIG. 4 is a configuration diagram of the camera section in FIG. 3, and FIG. 5 is a timing chart of signals in each section in FIG. 2 ... IL-CCD, 3 ... Signal processing unit, 4 ... Solid-state image sensor drive circuit, 5 ... Solid-state image sensor vertical drive circuit, 6 ...
Clamp signal controller, 7 ... Signal processing pulse generation circuit.

Claims (1)

[Claims] 1. A solid-state image pickup device comprising a plurality of read signals for reading charges accumulated in a photoelectric conversion element of the solid-state image pickup device into a vertical transfer register of the solid-state image pickup device within one vertical blanking period. In a video camera device that electrically controls the accumulation time of signal charges extracted as a television signal from a photoelectric conversion element, a clamp signal for fixing the optical dark portion of the output signal of the solid-state image pickup element to an arbitrary potential is A video camera device characterized by being stopped for an arbitrary period including the accumulation time.