JPS59133784A - Solid state image pickup device - Google Patents

Abstract

PURPOSE:To always obtain an image with high sensitivity and high quality in response to the brightness of a subject from a high level to a low level of intensity of illumination, by controlling intermittently the field scan of a solid state image pickup element in response to the video signal level. CONSTITUTION:A solid state image pickup element 1 is intermittently scanned by a scan control circuit 10 so as to set the output level of a video amplifying circuit 6 at a fixed level at a low level of intensity of illumination where the video output signal is not set at a fixed output level despite a full-open state of a diaphragm 3. Thus the scan is discontinued for each prescribed field, and signals are stored with the storing capacity. Then a video signal having a fixed output level is obtained as the output of the circuit 6. This video signal is immediately written into and read out of a video memory circuit 9 with the control signal given from a video memory control circuit 11. As a result, a video signal is obtained in each field as an output. With this video signal the video signal lacking part of the scan pause period of the element 1 is supplemented by the repetitive read-out of the circuit 9. Thus it is possible to obtain the continuous video signals of a fixed output level with no flicker.

Description

[Detailed Description of the Invention] The present invention relates to a solid-state imaging device using an integrated imaging element,
This invention relates to the running control of a solid-state imaging device that is advantageous when the output level of the video signal from the solid-state imaging device is low.

A conventional device of this type was the one shown in Fig. m1. In the figure, (1) is a solid-state image sensor, (2) is a lens, (
3) is an aperture, (4) is a lens motor that opens and closes the aperture (3), (5) is a servo amplifier that drives the Fi lens mask, and (6) is an image that amplifies the video signal from the solid-state image sensor (1). The amplification circuit 4 (7) is a scanning pulse generation circuit for scanning the solid-state image sensor (1) at a constant field period;
(8) is a video output terminal.

Next, the operation will be explained. The light from the subject is filtered through the aperture (3
) is adjusted to an appropriate amount of light, and the lens (2) directs the light to the light receiving section of the solid-state image sensor (1). The solid-state element (1) converts this optical image into an electric signal and outputs it as a weak video signal to the video amplification circuit (6). As shown in the shape At, a constant output is amplified to a level vO and output to the video output terminal (8). The amount of light is automatically adjusted by the diaphragm (3) so that the brightness of the light receiving section of the integrated image sensor (1) remains constant even when the brightness of the subject changes. In operation, the video signal output of the video amplifier circuit (6) is connected to the servo amplifier (5).
) is converted into a drive signal for the lens motor (4), and is obtained by driving the lens motor (4) and opening/closing the diaphragm (3) to a constant output level vO.

Conventional solid-state imaging devices are configured as described above, so if the subject is sufficiently bright, an image signal with a constant output level Vo can be obtained by using the 11th clause of aperture (3). When the light is low, even if the aperture (3) is fully opened, the video output level Vl remains constant as shown in waveform 2 in Figure 3, and is smaller than the Bell VO, resulting in poor image quality with insufficient sensitivity and S/N ratio. There was a drawback.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and it inputs a video signal of = from a solid-state image sensor to a video memory, and depending on the signal level, solid-state imaging lI! By intermittently controlling the field scanning of the element and controlling the video memory's exposure and d-out in synchronization with this control, high sensitivity and high sensitivity are always maintained depending on the brightness of the subject from high to low illuminance. It is an object of the present invention to provide a solid-state imaging device with high quality considerations.

An embodiment of the present invention will be described below with reference to the drawings. Second
In the figure, (1) is a solid-state image sensor, (2) is a lens,
(3) is the aperture, (4) is the lens motor that opens and closes the aperture (3), (5) is the servo amplifier that drives the lens motor, and (6) is the amplification of the video signal from the solid-state imaging probe (1). (7) is a scanning pulse generation circuit for quantifying the solid-state imaging probe (1); (8) is a video output terminal;
(9) is the output video signal of the video amplification circuit (6), -
The video memory circuit (10) that performs the output changes the scanning interval of the solid-state image sensor (1) by controlling the scanning pulse generation circuit (7) according to the output level of the video 1# signal, that is, the field scanning. A scanning control circuit that intermittently scans the sub-cape,
(11) is a video memory circuit (8) in synchronization with the scanning control of the solid-state image sensor (1) by the scanning control circuit (10).
T + 5 for collection and funding! This is a video meseri control circuit that provides I +1.

Next, the operation will be explained. The light from the subject is filtered through the aperture (3
), the light is adjusted to an appropriate light weight, and an image is formed by the lens (2) on the light receiving section of the solid-state sensor (1). Solid fI&
The 1-point element (1) converts this optical image into a cloud signal and outputs it as a weak image No. 18 to the image amplification circuit (6).
This inverter amplification circuit (6) provides a constant output as shown in the waveform AI in FIG. 3 and is amplified to the level VO. The light weight is automatically adjusted by the aperture (3) so that the brightness of the light receiving section of the solid-state imaging element (1) remains constant even when the brightness of the subject changes. This previous work was video amplification episode wI (6)
The image signal output is converted by the servo amplifier (5) into a drive signal for the lens motor (4), and the lens motor (4) is outputted at a constant level and the aperture is adjusted to a value of VO.
3) can be obtained by opening and closing. This constant output video signal AI of the bell VO is transferred to the video memory circuit (
9) The d-giving was performed at the same time as the vow was made manually.
The same waveform as the human waveform AI, such as waveform B1 in FIG. 3, is output to the video output terminal (8). Figure 3
IXT2, ..., Tls is the oth feed Jl of the video signal
/do, 1st field, %2 field,..., '4
15 field, and τ is the field period in seconds.

In this way, if the brightness of the subject is sufficient, f′i 1st
Figure 1. The previous work is exactly the same as the American solid-state imaging device.

In this case, the output of the scan pulse generation circuit (10) is always low voltage as shown in the waveform shown in Figure 3, CI, and the scan pulse generation circuit (7)
is uncontrolled solid-state photography 111! Element (1) remains in continuous scanning. Also, the output of the video memory circuit Is (11) has the waveform D*-! in FIG. Like L and DI-b, it always shows a high potential, and storage and reading are always performed for each field.

Next, when the aperture (3) is fully opened and the illuminance is low enough that the video output signal is output at a constant level and no bell-to occurs, the storage capacity of the solid-state imaging element (1) is used to control the travel control circuit. (
11) so that the output level of the video amplification circuit (6) becomes a constant two-power level VO as shown in waveform A3 in Fig. 3.
.

, Tt, Ta, T4.6, T7, . . . The quantification is stopped during the valley fields, and the signal is accumulated by the # product ng force, and only in each field of T2, T5, T8, . Scanning is performed, and AsTz, A3T5, A3T8, A3T11 . ...
video signal can be obtained. This consideration signal A3T2, As
Ts, AsTs, AsTo, . . . are control signals from the video camera return control circuit (11), waveform D in FIG.
s-aki Tz, T5, T8, . . . In response to the one-input command for each field and the continuous output command for waveforms Da-b, the video memory circuit (9) is immediately loaded and read out, and the output shown in FIG. Waveform B3, T2, T3, T4
, T5, T6, T7, T8, T9, . . . , the video value -$ A3T2, AxTz, A3T2, As
Ts, AaTs, AsTs, AaTs, As'rs,
. . . is obtained, and in this video signal, the video signal missing portion of the solid-state image sensor (1) during the short-term investment suspension period is transferred to the video memory circuit (
The light is supplemented by the repetition of step 9), and is sent to the video output terminal (8) as a flicker-free, continuous, fixed output video signal with a bell vO.

If the illumination is much lower than in the above case, use solid-state photography 1#! J
In order to further increase the #strike force of child (1), scan control 1g 1 timeg (10) causes scanning pauses as shown in waveform C4 in Fig. 3. TOlTl, T2, T4, TsXTs
, T8, T9, TIO, -..., and the nine fields of waveform A4 (Ta, T7, 'I'll,...
・Fixed output between the strokes fJjA of each field /
/< /L/ Vo f motsu A4Ta, A4T7, A
4Tu,...) Obtain the first video number. This train signal A4
T3, A4T7, A4T11, . . . are control signals from the video memory system m (11), waveforms D4-a in FIG.
, T3, T7, Tll, . . . and waveform J) 4-b are immediately inserted into the video memory circuit (9), d output is performed, and the waveform is output as the output. B4 Ig (Ts, T4, T5, T
6.7, Ta.

Video signal AaT in each field of T9, TIG,...
a, A4T3, A4T3, A4T3, A4T7, A4T
7, A4T7, A4T7, . . . are obtained and sent to the video output terminal (8).

In the above embodiment, the running period dark control is performed in units of field period of τ = 1/60 seconds, but τ = -1/30.
The measurement may be performed in units of frame periods in seconds.

As described above, according to the present invention, the field positioning of the solid-state sensor/iron element is intermittently controlled in accordance with the video signal level, and the image manually stored in the video memory is controlled (in synchronization) in accordance with the control output. By controlling the input and output of the single-image signal, it is possible to obtain high-quality images with a fixed output level from the high-light to low-light areas of the subject, and the j-envy sensitivity -8N ratio. There is.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing a conventional solid-state imaging device;
The figure is a block diagram showing an embodiment of an integrated camera system according to the present invention. FIG. 83 is a waveform diagram for explaining the # operation in FIGS. 1 and 2. (1)...Solid-state camera 1m element, (6)...Video amplification circuit, (9)...Video memory times m, (10)...Run flltll groan times IS, (11)... Video memory control circuit In the figures, the same reference numerals indicate the same or corresponding parts. Agent Makoto Kuzuno - Figure 1 Figure 2

Claims (1)

[Claims] 1iil image from solid-state image sensor! A video amplification circuit that amplifies the signal, a video memory circuit that outputs the output video signal of this video amplification circuit, and a video memory circuit that outputs the output video signal from this video memory circuit, and when the level of the video signal output from this video memory circuit is below a predetermined level, The field scanning of the integrated image pickup device is intermittently performed using f! What is claimed is: 1. A solid-state imaging device comprising: a scan control circuit that controls tJ, and a video memory control circuit that controls input and output of the video memory according to the scan control output.