JPS62142496A - Color camera equipment - Google Patents

Abstract

PURPOSE:To attain sure white-level balance adjustment even when the aperture of a diaphragm is changed manually by providing an automatic white level balance adjustment circuit. CONSTITUTION:The automatic aperture control circuit 2 controlling the diaphragm 5 of a motor-driven diaphragm device 1 consists of an error signal generating circuit 12 detecting an error signal from an image pickup output, e.g., a luminance signal Y and an arithmetic circuit 13 comparing an aperture state detection signal from a potentiometer 14 as a voltage sending circuit generating a voltage in response to the aperture state of the diaphragm and the error signal to control a motor 6, and the potentiometer 14 is connected between a power supply +B4 and the ground. A switch SW1 has a slider (r) connected to one terminal of the motor 6, an automatic aperture control fixed contact (a) connected to the power supply +B2 and a manual aperture variable fixed contact (m). A switch SW3 is the 3rd switch operated in interlocking with the 2nd switch SW2 and operates the automatic aperture control circuit 2 forcibly regardless of the interruption of the automatic aperture control circuit 2 by the switch SW1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color camera device, and particularly to an automatic aperture device thereof. Conventional devices of this kind have an electric aperture device, which detects an error signal from the imaging output, and can control the aperture of the electric aperture device to an appropriate aperture state based on this error signal, and can also remove this control. This allows you to change the aperture by turning the aperture ring by hand.

By the way, when changing the aperture manually, if you want to control the automatic white level balance adjustment circuit, it is necessary to manually adjust the aperture in advance, otherwise white level balance adjustment will not be possible. becomes.

In view of this, the present invention provides that even when changing the aperture manually, when operating the automatic white level balance adjustment circuit, the automatic aperture control circuit operates normally and ensures that the white level balance (white It is an object of the present invention to provide a color camera device in which balance adjustment is performed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. (1) shows an electric diaphragm device, which consists of a diaphragm (5) provided in a lens system (4) and a diaphragm (5) of this diaphragm (5).
and a motor (6) that drives the motor. (8)
is a camera head circuit, which obtains, for example, three color red, green, and image signals R, G, and B from an image pickup tube, and these signals are supplied to a signal processing circuit (9). From this signal processing circuit (9), a luminance signal Y and a color difference signal RY are output.
, B-Y are obtained and supplied to an encoder (10) of a desired system, for example, the NTSC system. Furthermore, (11) is NT
This is an output terminal from which an SC system composite color video signal can be obtained.

The signal processing circuit (9) includes an automatic black level balance adjustment circuit (3) in addition to circuits such as a matrix circuit and a γ correction circuit.
and an automatic white level balance adjustment circuit (7). SW2 is a switch (second switch) for operating these adjustment circuits (3) and (7), and has a movable contact t, a fixed contact W for self-level balance adjustment command, and a fixed contact W for black level balance adjustment command. have. The movable contact t is connected to the power supply +83 (the power supply voltage is set to V3), and by switching the movable contact t, the adjustment circuit +31.
(71 can be selectively brought into operation.

Note that n is a neutral contact when none of the adjustment circuits (31, (71) are operated.

(2) is an automatic aperture control circuit that controls the aperture (5) of the electric aperture device (1) described above to an appropriate aperture state. This includes an error signal generation circuit (12) that detects an error signal from the imaging output, for example, a luminance signal Y, and the error signal and the aperture (5).
) and a computation circuit (comparison circuit) (13) that controls the motor (6) by comparing and calculating the aperture state detection signal from the potentiometer (14) as a voltage generating circuit that generates a voltage according to the aperture state of the potentiometer (14). has been done. The potentiometer (14) is controlled between the power supply (power supply voltage is V4) +84 and ground.

One end of the motor (6) has a 10B power supply during automatic aperture control.
2 to give a reference voltage of □, and the arithmetic circuit (13) supplies a voltage of 0 to Vl to the other end of the motor (6).
The voltage is applied to the Motor (6)
is applied through SW1. This switch S W 1 has a movable contact r connected to one end of the motor (6), a fixed contact a for automatic aperture control connected to the power supply +B2, and a fixed contact m for manual aperture adjustment.

SWa is a third switch that operates in conjunction with the second switch SW2, and by this third switch SW3,
Automatic diaphragm control circuit (2
), the automatic diaphragm control circuit (2) is forced to operate despite the shutoff operation. The third switch SW3 has the same configuration as the second switch SW2, and the fixed contacts w and b are both connected to the power supply 1B2 whose power supply voltage is □, and the movable contact t is connected to the fixed contact of the first switch SW1. Connected to contact m. Further, the fixed contact of the second switch SW2 is particularly connected to the error signal generating circuit (12).

Next, let us explain the operation of this device. Electric diaphragm device (1)
is controlled by the automatic aperture control circuit (2) to aperture (5)
When changing automatically, switching pressure is applied from the movable contact r of the first switch SW1 to the fixed contact a side. Then, the rotation of the motor (6) is controlled based on the error signal detected from the luminance signal Y as the imaging output. For example, assume that when the motor (6) rotates in the forward direction, the aperture of the diaphragm (5) becomes small, and when the motor (6) rotates in the reverse direction, it becomes extra large. Also, motor (6)
Assume that the aperture becomes small when given. Also, aperture (5
) is fully open, a voltage of 0 is generated from the potentiometer (14), and when it is completely closed, a voltage of v4 is generated and supplied to the arithmetic circuit (13), respectively. The arithmetic circuit (13) outputs V4 to V4 depending on the magnitude of the luminance signal Y.
When an error signal with a voltage of 0 is supplied and the level of the brightness signal Y is higher than the reference level, the voltage applied to the other end of the motor (6) is set to be greater than 111, and the level of the brightness signal Y is increased. When it is lower than the reference level, it is applied to the other end of the motor (6) and the level of the error signal from the error signal generation circuit (12) and the detection signal from the potentiometer (14) are compared at (13) and they match. Up to motor (6
) is rotated in the forward or reverse direction, and when the voltage at the other end becomes □, the motor (6) stops its rotation.

Next, when adjusting the aperture (5) manually, the movable contact r of the first switch SWx is switched to the fixed contact m. At this time, if the movable contacts of the second and third switches SW2 and SW3 are switched to the neutral fixed contact n, automatic aperture control is not performed and the aperture (5) is rotated by the aperture ring (not shown). It can be changed manually depending on the movement. Also, when the movable contact t of the second and third switches SW2゜3W3 is switched to the fixed contact W or b, the voltage -1 from the power supply B2 is applied to the motor through the third and first switches SW3 and SWt. (6)
Since it is given to one end, automatic aperture control is performed in the same way as described above, and automatic white level balance adjustment circuit
) or the automatic black level balance adjustment circuit (3) is activated.

In this case, the automatic aperture control circuit (2) operates normally when adjusting the white level balance, but when adjusting the black level balance, the voltage v3 from the power supply 1B3 is applied to the second switch SW2.
The voltage of the error signal is fixed at V4, the motor (6) rotates forward, and the diaphragm (5) is completely closed. In this way, automatic black level balance adjustment is ensured.

According to the present invention described above, even when changing the aperture manually, the automatic white level balance adjustment circuit operates normally when the automatic white level balance adjustment circuit is operated, so the automatic white level balance ( white balance) tl! It is possible to perform I adjustment.

[Brief explanation of drawings]

The figure is a block diagram showing one embodiment of the present invention. (1) is an electric diaphragm device, (2) is an automatic diaphragm control circuit, (
3) is automatic black level balance adjustment circuit, (4) lens system, (5) is diaphragm, (6) is motor, (7) is automatic white level balance adjustment circuit, (9) is signal processing circuit, (12)
1 is an error signal generation circuit, (13) is an arithmetic circuit, (14) is a potentiometer, and SW1 to SW3 are first to third switches.

Claims (1)

[Claims] An electric aperture device, an automatic aperture control circuit that detects an error signal from the imaging output and controls the aperture of the electric aperture device to an appropriate aperture state, and an automatic aperture control circuit that automatically adjusts white balance upon receiving a video signal. white level balance adjustment circuit,
In a color camera device comprising an aperture switching mechanism that controls the operation of the automatic aperture control circuit and switches between a manual control mode and an automatic control mode, the automatic white level balance adjustment circuit is activated. A means for switching the aperture switching mechanism to an automatic control mode is provided, and when adjusting the automatic white level balance, the aperture switching mechanism is set to the automatic control mode, the automatic aperture control circuit is operated, and a video signal of a predetermined level is obtained. A color camera device characterized by being able to perform more accurate white level balance adjustment.