JPH06334927A - Illuminating device - Google Patents

Abstract

PURPOSE:To automatically stop the emission of illuminating light in a period while a photodiode accumulates signal charge to be discharged to an overflow drain terminal. CONSTITUTION:In a period from the leading edge of a field shifting pulse 1a up to the trailing edge of a shutter pulse b1 in the ON state of an illumination by a key input means 20, a flip flop 12 is turned off, a switch 13 is turned off and power supply voltage V3 to be supplied to a halogen lamp 15 is turned to OV, so that light is not emitted from the lamp 15. Consequently the emission of illuminating light can be automatically stopped in a period that the photodiode accumulates signal charge to be discharged to the overflow drain terminal of a CCD.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device used for a video camera using a solid-state image pickup device, and more particularly to a lighting device capable of reducing power consumption.

[0002]

2. Description of the Related Art Conventionally, in a single-chip video camera, a CCD (Charge Coupling) is generally used as a solid-state image sensor.
led device) is used to perform sampling and holding on the video signal obtained by photoelectrically converting the video for each field.
A video signal is obtained by processing the sampled and held signal as an analog signal.

On the other hand, as a general domestic video camera, a video camera in which a small illuminating device which emits light by a power supply voltage from the video camera main body can be attached is becoming popular. The illumination device in this case is used as a light source that continuously emits light such as a halogen lamp, and supplies a power supply voltage to the light source to emit light by turning on an illumination switch on the video camera body side.

FIG. 4 is a block diagram illustrating a CCD used in such a conventional video camera.

In FIG. 4, a CCD 51 has a configuration in which photodiodes 61 corresponding to pixels arranged in the vertical direction and vertical CCDs 62 are alternately arranged in the horizontal direction. The vertical transfer pulse input terminal 52 of the CCD 51 is
4-phase vertical transfer pulse φV1, φV2, φV3, φV4
Also, the field shift pulse a1 is guided. The two-phase horizontal transfer pulses φH1 and φH2 are introduced to the horizontal transfer pulse input terminal 53 of the CCD 51.

A direct current voltage V1 is guided to the overflow drain terminal 54 of the CCD 51, and a shutter pulse b1 is superposed on the direct current voltage V1.

The signal charge accumulated in the photodiode 61 is swept to the overflow drain terminal 54 by the shutter pulse b1 and transferred to the vertical CCD 62 by the field shift pulse a1. The signal charges transferred to the vertical CCD 62 are transferred to the horizontal CCD 63 for each horizontal line by being supplied with four-phase vertical transfer pulses φV1, φV2, φV3, and φV4. The signal charges transferred to the horizontal CCD 63 are supplied to the output buffer 64 of the charge detection unit by being supplied with the two-phase horizontal transfer pulses φH1 and φH2. The output buffer 64 converts the signal charge from the horizontal CCD 63 into a pixel signal and guides this pixel signal to the CCD output terminal 55 as a CCD output signal c1. Video camera is CCD
The CCD output signal c1 output from the output terminal 55 is sampled and held by the sample and hold circuit, and the sampled and held signal is subjected to analog signal processing to obtain a video signal.

FIG. 5 is a block diagram showing the photodiode 61 and the vertical CCD 62 of FIG. 4 in more detail.

The signal charges accumulated in the photodiode 61 are transferred to the vertical CCD 62 by the field shift pulse a1 (see FIG. 4). The vertical CCD 62 has four sets of electrodes A1, A2, A3, which are provided on a semiconductor substrate via an insulating film.
A4 is repeated and arranged in the vertical direction. Vertical CC
In D62, the potential well of the semiconductor substrate is moved by supplying four-phase vertical transfer pulses φV1, φV2, φV3, and φV4 to the four sets of electrodes, respectively. As a result, the charges transferred to the vertical CCD 62 are transferred to the horizontal CCD 63 (see FIG. 4) for each horizontal line.

FIG. 6 is a timing chart showing the operation of a video camera using such a CCD 51.
6A shows the power supply voltage V2 supplied to the halogen lamp of the lighting device, and FIG. 6B shows the vertical transfer pulse φV.
1, φV2, φV3, φV4 and the field shift pulse a1 are shown, and FIG. 6C shows the shutter pulse b1.

First, in the n-1 field, when the illumination switch on the video camera body side is turned on, the power supply voltage V2 supplied to the illumination device is 0 as shown in FIG. 6 (a).
From V to 6V, the lighting device keeps emitting light. This state is maintained even in the subsequent n fields, n + 1 fields .... On the other hand, CC of video camera
D51 transfers the signal charge accumulated in the photodiode 61 to the vertical CCD 62 by the field shift pulse a1 shown in FIG. 6B, and the signal charge transferred to the vertical CCD 62 is shown in FIG. Phase vertical transfer pulses φV1, φV2, φV3, and φV4 are transferred to the horizontal CCD 63 for each horizontal line. The signal charges transferred to the horizontal CCD 63 are two-phase horizontal transfer pulses φH1 and φH2.
Is supplied to the output buffer 64. Further, the CCD 51 of the video camera causes the signal charge accumulated in the photodiode 61 to flow to the overflow drain terminal 5 by the shutter pulse b1 shown in FIG.
Sweep to 5. As a result, the signal charge accumulated in the photodiode 61 during the period T11 from the rising of the field shift pulse a1 to the rising of the shutter pulse b1 is swept to the overflow drain terminal 55 by the shutter pulse b1. On the other hand, the signal charge accumulated in the photodiode 61 during the period T12 from the rise of the shutter pulse b1 to the rise of the field shift pulse a1 is transferred to the vertical CCD 62 by the field shift pulse a1.
Therefore, the period T11 becomes the non-exposure time, and the period T12
Is the exposure time. The video camera appropriately exposes the CCD 51 by adjusting the timing of the shutter pulse b1 according to the brightness level of the image.

In the conventional lighting device used in such a video camera, the lighting switch on the video camera body side is turned on to maintain the light emitting state to compensate for the insufficient light amount of the subject. The signal charge discharged to the terminal 55 is transferred to the photodiode 61.
Since the illumination light is emitted also in the period T11 in which the charge is accumulated, the power supply voltage supplied to the lighting device in this period T11 is wasted.

[0013]

In the above-described conventional lighting device, even during the period when the photodiode accumulates the signal charge swept to the overflow drain terminal,
Since the illumination light is emitted, the power supply voltage supplied to the lighting device during this period is wasted.

Therefore, an object of the present invention is to provide an illuminating device capable of automatically stopping the emission of the illuminating light during the period when the photodiode accumulates the signal charge swept to the overflow drain terminal.

[0015]

The illumination device of the present invention sweeps out the signal charge accumulated in the photodiode to the overflow drain by supplying the shutter pulse, and supplies the field shift pulse or the field shift pulse. Is an illumination device used in a video camera that uses a solid-state image sensor that transfers the charge accumulated in the photodiode to the charge detection unit and outputs it as a pixel signal when a frame shift pulse created by counting Then, the light emitting means that emits illumination light when a power supply voltage is supplied and the state where the shutter pulse is supplied to supply power to the light emitting means are switched, and the field shift pulse or the frame shift pulse is changed. By being supplied, power is supplied to the light emitting means. The characterized by comprising a switching switched power supply means to a state of stop.

[0016]

According to this structure, the power supply means is switched to the state in which the shutter pulse is supplied to supply power to the light emitting means, and the field shift pulse or the frame shift pulse is supplied. Since the supply of power to the light emitting means is switched to the stopped state, the emission of the illumination light can be automatically stopped during the period when the photodiode accumulates the signal charge swept to the overflow drain terminal.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a lighting device and a video camera showing an embodiment of the lighting device according to the present invention.
For D, the same one as the CCD 51 shown in FIG. 4 is used.

In FIG. 1, reference numeral 1 is a lighting device,
The illumination device 1 is supplied with the field shift pulse a1 and the shutter pulse b1 from the video camera 5.

First, the video camera 2 will be described.

The CCD drive circuit 11 of the video camera 2 is
The four-phase vertical transfer pulses φV1, φV2, φV3, and φV4 and the field shift pulse a1 are supplied to the vertical transfer pulse input terminal 52 of the CCD 51, and the two-phase horizontal transfer pulses φH1 and φ are supplied to the horizontal transfer pulse input terminal 53 of the CCD 51.
Supply H2. Further, the CCD drive circuit 11 is a CCD
DC voltage V1 is applied to the overflow drain terminal 54 of 51
And supplies the shutter pulse b1 superimposed on the DC voltage V1. As a result, the CCD 51 is
The same operation as in the conventional example is performed, and the CCD output signal c1 is output.

Further, the CCD drive circuit 11 guides the shutter pulse b1 to the set terminal (S) of the flip-flop 12 of the lighting device 1 and the field shift pulse a1 to the reset terminal (R) of the flip-flop 12.

Next, the lighting device 1 will be described.

The non-inverting output terminal (Q) of the flip-flop 12 has a switch 13
It is connected to the OFF control signal input terminal. As a result, the flip-flop 12 supplies the on / off control signal d1 to the on / off control signal input terminal of the switch 13.

The switch 13 is an on / off control signal d1.
Is turned on when is at a high level, and an on / off control signal d1
Is off when is low.

On the other hand, the key input means 20 is for turning on and off the illumination by operating the keys. When the illumination is turned on, the high level on / off control signal e1 is turned on by the switch 14. , Is supplied to the OFF control signal input terminal, and when the illumination is set to OFF, the low level ON / OFF control signal e1 is supplied to the ON / OFF control signal input terminal of the switch 14.

The switch 14 is an on / off control signal e1.
Is high level, it is turned on, and on / off control signal e1
Is off when is low.

On the other hand, the power supply terminals 21 and 22 form a DC power supply input terminal pair, and a DC voltage of 6 V is introduced to the power supply terminal 21 and a voltage of 0 V is introduced to the terminal 21. The power supply terminal 21 is connected to one terminal of the switch 14. The other terminal of the switch 14 is connected to one terminal of the switch 13. The other terminal of the switch 13 is connected to one terminal of the halogen lamp 15. The other terminal of the halogen lamp 15 is connected to the power supply terminal 22. With such a connection, the power supply voltage V3 is supplied to one terminal of the halogen lamp 15.

With this connection, in the lighting device 1, when the illumination is turned off by the key input means 20, the switch 14 is turned off, and when the illumination is turned on by the key input means 20, the switch 14 is turned on. On the other hand, the flip-flop 12 is reset by the rising edge of the field shift pulse a1, outputs a low-level on / off control signal d1, and turns off the switch 13. The flip-flop 12 is set by the rise of the shutter pulse b1, outputs a high-level on / off control signal d1, and turns on the switch 13.

FIG. 2 is a timing chart showing the operation of such an embodiment, and FIG. 2 (a) shows the halogen lamp 1.
2 (b) shows the vertical transfer pulses φV1, φV2, φV3, φV4 and the field shift pulse a1, and FIG. 2 (c) shows the shutter pulse b1.

First, in the n-1 field, since the illumination is set to off by the key input means 20, the switch 14 is turned off and the power supply voltage V3 supplied to the halogen lamp 15 is shown in FIG. 2 (a). Thus, it becomes 0V. After that, when the field shift pulse a1 shown in FIG. 2B rises in the n field, the flip-flop 12 is reset and the switch 13 is turned off. In this state, if the setting is switched from illumination off to illumination on by the key input means 20, the key input means 20
Outputs a high level and the switch 14 is turned on, but the switch 13 is turned off. Therefore, the power supply voltage V3 supplied to the halogen lamp 15 is as shown in FIG.
As shown in FIG. As a result, the halogen lamp 15 maintains a state in which it does not emit light. After this,
As shown in (c), when the shutter pulse b1 rises, the flip-flop 12 is set and the switch 13
2 is turned on, the power supply voltage V3 supplied to the halogen lamp 15 becomes 6 V as shown in FIG. 2A, and the halogen lamp 15 emits light. After that, when the field shift pulse a1 rises in the (n + 1) th field,
The flip-flop 12 is reset and the switch 13
Is turned off, and the power supply voltage V3 supplied to the halogen lamp 15 becomes 0 V as shown in FIG.

As a result, when the illumination is turned off by the key input means 20, the power supply voltage V3 supplied to the halogen lamp 15 is 0 V, and the halogen lamp 15 does not always emit light. When the illumination is turned on by the key input means 20, the power supply voltage V3 supplied to the halogen lamp 15 is 0 V during the period T11 from the rising of the field shift pulse a1 to the rising of the shutter pulse b1. Does not emit light, and when the illumination is set to ON by the key input means 20, the power supply voltage V3 supplied to the halogen lamp 15 is 6 during the period T12 from the rise of the shutter pulse b1 to the rise of the field shift pulse a1.
It becomes V and the halogen lamp 15 emits light.

Therefore, during the period T12 when the exposure time is reached, the CCD 51 takes an image in a state where the halogen lamp 15 emits light and the illumination light is projected onto the subject, and during the period T11 when the non-exposure time is reached, the halogen lamp 15 is turned on. Turn off the light. Therefore, the power supply voltage of the illumination light can be effectively used, the power consumption can be reduced, and the shooting time in a state where the illumination light is projected can be increased when a battery is used as the power supply. it can.

FIG. 3 is a block diagram showing another embodiment of the illumination device according to the present invention, and the same video camera as the video camera 5 shown in FIG. 1 is used as the video camera.

In FIG. 3, reference numeral 3 is an illuminating device using a discharge lamp 32, and the illuminating device 3 includes a video camera 5
Field shift pulse a1 and shutter pulse b from
1 is supplied.

The CCD drive circuit 11 of the video camera 5 is
The shutter pulse b1 is led to the set terminal (S) of the flip-flop 42 of the lighting device 1, and the field shift pulse a1 is led to the reset terminal (R) of the flip-flop 42.

The illumination device 3 will be described below.

The control signal e1 from the non-inverting output terminal (Q) of the flip-flop 42 is supplied to the control signal input terminal of the discharge lamp drive circuit 31.

On the other hand, the key input means 30 sets the illumination on and the illumination off by the key operation. When the illumination is on, the high level on / off control signal f1 of the discharge lamp drive circuit 31 is set. The ON / OFF control signal input terminal is supplied, and when the illumination is OFF, the low-level ON / OFF control signal f1 is supplied to the ON / OFF control signal input terminal of the discharge lamp drive circuit 31.

The discharge lamp drive circuit 31 is turned on when the on / off control signal f1 is high level, and turned off when the on / off control signal f1 is low level. Further, the discharge lamp drive circuit 31 drives the discharge lamp 32 when the control signal e1 from the non-inverting output terminal Q of the flip-flop 12 is switched to the high level when the on / off control signal f1 is at the high level. Is supplied to turn on the discharge lamp 32. Here, the time from when the control signal e1 is switched to the high level until the first pulse is supplied to the discharge lamp 32 is set to be always constant. The discharge lamp driving circuit 31 supplies a driving pulse voltage to the discharge lamp 32 when the control signal e1 from the flip-flop 12 is switched to the low level when the on / off control signal f1 is at the high level. The discharge lamp 32 is stopped and turned off.

According to such an embodiment, when the lighting is set to ON, the discharge lamp 32 operates the shutter pulse b.
In the period T12 from the rise of 1 to the rise of the field shift pulse a1, light is emitted by the pulse voltage from the discharge lamp drive circuit 31, and the light is turned off in the period T11 from the rise of the field shift pulse a1 to the rise of the shutter pulse b1. In addition to having the same effect as the first embodiment, the discharge lamp drive circuit 31 sets the time from the rise of the shutter pulse b1 until the first pulse is supplied to the discharge lamp 32 to be always constant. There is also an effect that it is possible to prevent the occurrence of flicker.

Although the halogen lamp and the discharge lamp are used as the lighting device in the embodiments shown in FIGS. 1 and 2, other light emitting means such as a light emitting diode may be used. In addition, the embodiment of FIGS. 1 and 2 applies the present invention to the one in which the charge accumulated in the photodiode is transferred to the charge detection unit for each field and is output as a pixel signal. It may be applied to one in which the accumulated charges are transferred to the charge detection unit and output as a pixel signal. In this case, a frame shift pulse generated by the solid-state imaging device counting field shift pulses is supplied. By doing so, the charge accumulated in the photodiode is transferred to the charge detection unit and output as a pixel signal, and the power supply unit stops the supply of power to the light emitting unit by supplying the frame shift pulse. It may be configured so as to switch to a state in which it is turned on.

[0043]

As described above, according to the present invention, the emission of the illumination light can be automatically stopped during the period when the photodiode accumulates the signal charge swept to the overflow drain terminal. The power supply voltage of light can be effectively used, the power consumption can be reduced, and the shooting time in the state where the illumination light is projected when the battery is used as the power supply can be increased.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a lighting device according to the present invention.

FIG. 2 is a timing chart showing the operation of the embodiment of FIG.

FIG. 3 is a block diagram showing another embodiment of the lighting device according to the present invention.

FIG. 4 is a block diagram illustrating a CCD used in a conventional video camera.

FIG. 5 is a block diagram showing the photodiode and vertical CCD of FIG. 4 in more detail.

6 is a timing chart showing the operation of the video camera using the CCD of FIG.

[Explanation of symbols]

 11 CCD drive circuit 12 Flip-flop 13, 14 switch 15 Halogen lamp 20 Key input means 51 CCD

Claims (1)

[Claims] 1. A shutter pulse is supplied to sweep out signal charges accumulated in a photodiode to an overflow drain, and a field shift pulse is supplied, or a frame shift pulse created by counting field shift pulses is supplied. A lighting device used in a video camera using a solid-state image sensor that transfers the charge accumulated in the photodiode to the charge detection unit and outputs it as a pixel signal. Light emitting means for emitting light, and switching to a state in which power is supplied to the light emitting means by supplying the shutter pulse, and power is supplied to the light emitting means by supplying the field shift pulse or frame shift pulse. Power supply that switches to a state where the power supply is stopped Lighting apparatus characterized by comprising a stage.