JPS62180683A - Video camera device - Google Patents

Abstract

PURPOSE:To remove a mechanical shutter from a high speed video camera device using an IL-CCD, to miniaturize the video camera device, and to reduce a weight, by controlling electrically the accumulation time of an electric charge read out in one vertical scanning period from a photoelectric transducer in a solid-state image pickup element. CONSTITUTION:Between from an electric charge readout pulse 26 at the first field to an electric charge readout pulse 28 at the first field, a signal electric charge accumulated in a photodiode is transferred to a horizontal transfer register with a vertical transfer pulse 30, and it is changed to a television signal at the first field, and between from an electric charge readout pulse 28 at the first field to an electric charge readout pulse 27 at the second field, the signal electric charge accumulated in the photodiode is transferred at high speed to the horizontal transfer register with a high speed vertical transfer pulse 31, and is outputted within a vertical fly-back line period from a signal output terminal 20. In other words, by controlling the accumulation time of the signal electric charge accumulated in the photodiode electrically, the same function as the mechanical shutter can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a video camera device using a solid-state imaging device with a vertical overflow-drain.

(Prior Art) In recent years, special playback such as low-speed playback and frame-by-frame playback is frequently performed on video decks, so high-speed video camera devices that reduce video blurring during special playback are attracting attention.

An example of a conventional high-speed video camera device will be described below with reference to the drawings.

A conventional high-speed video camera device using an interline charge-coupled solid-state image sensor, as shown in FIG. Line charge-coupled solid-state image sensor 4 (hereinafter referred to as IL-CCD4), IL-
It is composed of a drive section 5 that operates the CCD 4, and a signal processing section 6 that converts the signal output from the IL-CCD 4 into a television signal.When a shutter speed is selected by the shutter control section 3, the mechanical shutter 2 operates according to the selection. However, the light incident through the optical lens 1 while the mechanical shutter 2 is open is IT=-CCD4.
The signal is converted into an electrical signal by the signal processing section 6, and then converted into a television signal by the signal processing section 6.

The IL-CCD 4 used in such a conventional high-speed video camera device is constructed as shown in FIG. 7 is a photodiode that functions as a photoelectric conversion element;
8 is a vertical transfer register composed of vertical transfer gates 1 to 9, 10 degrees 11 and 12; 13 is isometrically common to vertical transfer gates 9 and 11; signal readout gates 1 to 114 are vertical transfer pulse supply terminals; , 15 are horizontal transfer gates 16 and 1
7 is a horizontal transfer register, 18 is a horizontal transfer pulse supply terminal, and 19 is a charge detection unit that converts the signal charge transferred from the horizontal transfer register 15 into a signal voltage. Diffusion amplifier (F], oating D 1ffus
ion A mpHf 1er). 2
0 is a signal output terminal, and 21 is a base voltage supply terminal.

In the IT, -CCD 4 configured in this way, the photodiodes 1 to 1<7 photoelectrically convert the light from the subject that enters through the optical lens 1, converting the signal charge into 1().
However, at this time, the excess charge is swept out to the vertical overflow drain by the DC potential supplied from the base voltage supply terminal 21. Further, the signal charge obtained by photoelectric conversion in the photodiode 7 is transferred to the signal readout gate 13.
After being read into the vertical transfer gates 9, 10, 11, and 12 constituting the vertical transfer lens 8 through the vertical transfer pulses supplied from the vertical transfer pulse supply terminal 14, the signals are read in the vertical direction, that is, the horizontal transfer register 15. The data are sequentially transferred in the direction of , and read into the horizontal transfer register 15 one horizontal line at a time. The signal charges read into the horizontal transfer register 15 are sequentially transferred to the charge detection section 19 by horizontal transfer pulses supplied from the horizontal transfer pulse supply terminal 18, and are converted into voltage by the charge detection section 19. , is output as a dot sequential signal from the signal output terminal 20, but this dot sequential signal is further converted into a television signal by the signal processing section 6 and output.

Therefore, the vertical transfer pulse supply terminal 14 of IL-CCD4
and the output timing of the vertical transfer pulses supplied to the base voltage supply terminal 21 will be explained with reference to FIG.

22 and 23 are charge read pulses that read signal charges from the photodiode 7 to the vertical transfer register 8; 24 are vertical transfer pulses that sequentially transfer the signal charges read out to the vertical transfer register 8 toward the horizontal transfer register 15; ,
25 is a base voltage control signal that controls the amount of excess charge swept out to the vertical overflow drain, and the base voltage of this base voltage control signal 25 is constant at vb.

Therefore, from the charge readout pulse 22 of the first field to the second
The signal charge accumulated in the photodiode 7 until the field's charge successive pulse 23 becomes the television signal of the second field based on the operation of the IL-CCD 4, and is read from the charge reading pulse 23 of the second field to the first field's television signal. The signal charge accumulated in the photodiode 7 until the charge succession pulse 22 becomes the television signal of the first field based on the operation of the IL-CCD 4.

(Problems to be Solved by the Invention) By the way, since the high-speed video camera device using the IL-CCD 4 uses the mechanical shutter 2, there is a problem that the size and weight of the video camera device increases. At the same time, since mechanical precision of the mechanical shutter 2 and the like is required, there is a problem in that the price of the high-speed video camera device also increases significantly.

The present invention was made in view of these problems, and instead of removing the mechanical shutter, it superimposes a new signal on the IL-CCD drive signal, thereby making it equivalent to a high-speed video camera device using a mechanical shutter. The purpose of the present invention is to provide a video camera device that provides the following performance.

(Means for Solving the Problems) The present invention provides two charge readout signals for causing a vertical transfer register to read charges accumulated in a photoelectric conversion element of a solid-state image sensor during a vertical retrace period; A high-speed vertical transfer signal that transfers the signal charge read to the vertical transfer register to the horizontal transfer register at high speed during two charge readout signals, and sweeps out the signal charge accumulated in the photoelectric conversion element to the vertical overflow drain. The device includes a solid-state image sensor driving section that outputs a substrate voltage control signal that switches the amount of excess charge between the high-speed vertical transfer period and other periods.

(Function) By setting the accumulation time of signal charges read out from the solid-state image sensor within one vertical scanning period, it has the same function as controlling the amount of incident light using a mechanical shutter.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the configuration of an embodiment of the present invention, and FIG.
- This is a timing chart of pulses input to the vertical transfer pulse supply terminal 14 and the substrate voltage supply terminal 21 of the CCD 4, and the same reference numerals as those in FIGS. 3 to 5 indicate the same parts.

The operation of the high-speed video camera device using the IL-CCD4 will be described below.

Now, 26, 27, 28 and 29 are charge read pulses that read out the signal charges accumulated in the photodiode 7 to the vertical transfer register 8 within the vertical retrace period, and 30 is the signal read out to the vertical transfer register 8. Charge horizontal transfer register 1
A vertical transfer pulse 31 sequentially transfers the signal charge in the direction of 5, between the charge readout pulse 26 and the charge readout pulse 28 and between the charge readout pulse 27 and the charge readout pulse 29, that is, within the vertical retrace period. [Horizontal transfer register] A high-speed vertical transfer pulse 32 transfers the excess charge accumulated in the photodiode 7 sequentially in the direction of the vertical overflow register 5.
The amount swept to the drain is controlled by switching between the high-speed vertical transfer period and other periods. In other words, the accumulation time of signal charges accumulated in the photodiode 7 is electrically switched between the vertical retrace period and the vertical scanning period. The ratio of the vertical retrace period t1 to the vertical scanning period t2 in this substrate voltage control signal 32 is 11:12, and the ratio of the vertical scanning period t2 is 1:900. is approximately 900 times greater, so during the vertical scanning period t2, the base voltage is increased from vb to Va by the increased amount.

Therefore, from the charge read pulse 26 of the first field to the first
The signal charge accumulated in the photodiode 7 until the field charge readout pulse 28 is transferred to the horizontal transfer register 15 by the vertical transfer pulse 30, and becomes the television signal of the first field, and the signal charge is transferred to the horizontal transfer register 15 by the vertical transfer pulse 30, and becomes the television signal of the first field. 28 to second field charge read pulse 27
The signal charge accumulated in the photodiode 7 up to this point is transferred at high speed to the horizontal transfer register 15 by the high-speed vertical transfer pulse 3I, and is outputted from the signal output terminal 20 within the vertical retrace period. In addition, the charge read pulse 2 of the second field
The signal charge accumulated in the photodiode 7 from 7 to the second field charge succession pulse 29 is transferred to the horizontal transfer register 15 by the vertical transfer pulse 30, and becomes the television signal of the second field. The signal charges accumulated in the photodiode 7 from the field charge read pulse 29 to the first field charge succession pulse 26 are transferred at high speed to the horizontal transfer register 15 by the high-speed vertical transfer pulse 31, and the vertical retrace period is completed. The signal is output from the signal output terminal 20 within the same period.

That is, by electrically controlling the accumulation time of the signal charge accumulated in the photodiode 7, it functions in the same manner as the mechanical shutter 2, so that the video camera device having the IL-CCD driving section of the present invention can operate at high speed. It can be used as a video camera device.

Although this embodiment has been described using IL-COD as an example of the solid-state image sensor, a frame transfer charge-coupled solid-state image sensor may be used instead.

(Effects of the Invention) As described above, according to the present invention, the accumulation time of charges read out from the photoelectric conversion element of the solid-state image sensor within one vertical scanning period can be electrically controlled.
- It is now possible to remove a mechanical shutter from a high-speed video camera device using COD, which has the effect of reducing the size and weight of the video camera device. Since target accuracy is no longer required, the price of the video camera device can also be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention, FIG. 2 is II of FIG. I of
FIG. 4 is a block diagram showing the overall configuration of a high-speed video camera device using the IL-CCD shown in FIG. 3.
FIG. 5 is a timing chart of signals output from the driving section of the IL-CCD shown in FIG. 3. 4...Solid-state image sensor, 5. Drive unit, 7.
Photoelectric conversion element, 8... Vertical transfer register, 15.
・Horizontal transfer register, 26, 27° 28, 29...
Charge read pulse, 31...High speed vertical transfer signal, 32
Base voltage control signal.

Claims (1)

[Scope of Claims] In a video camera device using a solid-state image sensor with a vertical overflow/drain, (a) a signal accumulated in a photoelectric conversion element of the solid-state image sensor during a first period within a vertical retrace period; (b) a first charge readout signal that causes signal charges to be read out to a vertical transfer register; (c) between the first period and the second period and between the second period and the second period; (d) a high-speed vertical transfer signal that causes signal charges read out to the vertical transfer register to be vertically transferred at high speed to a horizontal transfer register during a period between the second period and the first period; The period between the first period and the second period is applied to a first base voltage that controls the amount of excess charge that is swept out to the vertical overflow drain among the signal charges accumulated in the photoelectric conversion element. and a substrate voltage control signal that switches to a second substrate voltage lower than the first substrate voltage during the period between A video camera device comprising: a driving section for controlling the solid-state image sensor.