JPH0548549B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an electronic still camera that records still images on a rotating recording medium such as a magnetic disk, and particularly to power supply control for an electronic still camera.

[Background of the invention]

Recently, combinations of imaging devices such as solid-state image sensors and image pickup tubes and recording devices using magnetic recording media such as magnetic disks that are inexpensive and have a relatively large storage capacity have been developed. Electronic still cameras have been developed in which images are recorded on a magnetic recording medium and the images are reproduced using a separate reproduction device.

By the way, conventional electronic still cameras are configured to supply power to each circuit section that performs photographing and recording operations only when the shutter release button is operated, thereby preventing power from being wasted. There is. However, in conventional electronic still cameras, when the shutter release button is released, the power supply to each circuit that performs shooting and recording operations is immediately cut off. If it is canceled during operation, shooting/
There was a risk that recording operations would not be possible. Furthermore, when shooting in a timer mode such as a self-timer, when the shutter release button is operated, power is supplied to each of the circuit sections for a certain period of time, and these circuit sections are turned on again after the set time. However, since the timer start time was set to the start time of the shooting operation, the drive system of the motor, etc. related to shooting and recording operations may not be in perfect condition due to the start-up state. This was a case where no photographing/recording operations were performed.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an electronic still camera that can appropriately supply power to each circuit section that performs photographing and recording operations according to the photographing mode. The purpose is

[Summary of the invention]

In order to achieve the above object, the present invention provides an electronic still camera that rotates a rotating recording medium such as a magnetic disk and records a video signal representing a still image of a subject on the rotating recording medium, and provides sequence control using a timer mode. A timer mode establishment means for instructing the operation, and an operating means that operates in two strokes, instructing power supply to each circuit part in the first stroke, and instructing the photographing/recording operation in the second stroke. and a power supply control means that takes in the output signals of the timer mode setting means and the operation means and controls the power supply to each circuit section that performs photographing and recording operations, and the power supply control means receives the output signals from the release operation means. a first timer means that starts supplying power to each of the circuit units in response to a power supply instruction and maintains power supply to each of the circuit units for a certain period of time even if the power supply instruction is canceled; a second timer means that maintains the power supply to each of the circuit sections in response to a photographing/recording operation instruction and continues the power supply state until the photographing/recording operation is completed; and a second timer means that receives power from the operating means when setting the timer mode. Supplying power to each of the circuit units for a certain period of time according to a supply instruction, and photographing and recording the completion of the supply of power to each of the circuit units at a predetermined time before the start of the recording operation, and photographing the state of supply of the power. - Third timer means that is held until the recording operation is completed.

〔Example〕

Preferred embodiments of the electronic still camera according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows the configuration of an embodiment of an electronic still camera according to the present invention. In the same figure, the imaging section of the electronic still camera is mainly the afocal lens 1.
0, aperture 12, master lens 14, shutter 1
6 and a solid-state image sensor (CCD is used in this embodiment) 18;
It is comprised of an aperture drive device 20 that drives the aperture 12, a shutter drive device 22 that drives the shutter 16, and an automatic exposure control circuit 24 that controls the aperture drive device 20 and the shutter drive device 22.

The solid-state image sensor 18 is driven by drive signals from a vertical drive circuit 28 and a horizontal drive circuit 30, which operate in response to pulse signals output from a timing pulse generation circuit 26. The timing pulse generation circuit 26 is a circuit that generates various pulse signals for controlling each circuit section of the electronic still camera.

Furthermore, the imaging section includes a preamplifier 32 that samples the primary color signals R, C, and B obtained from the solid-state imaging device 18 and amplifies them to a predetermined level;
A process circuit 34 adjusts the primary color signals R, G, B outputted from the process circuit 34 to a predetermined value based on the output signal from the color temperature corresponding white balance circuit 44, and the primary color signals R, G, B outputted from the process circuit 34. Gamma correction circuit 3 performs color signal processing for gamma correction.
6, luminance signals _YH , YL-YH having predetermined signal bandwidths based on the primary color signals R, G, and _B output from the gamma _{correction circuit 36, and color difference signals R-YL ,} B.
_-YL , and based on these signals output from the matrix circuit 38, an NTSC video signal NTSC, a luminance signal Y+S including a composite synchronization signal S, and a color difference signal R- Encoder 40 that synthesizes Y and B-Y
Contains.

Further, the NTSC signal outputted from the encoder 40 is outputted to an electronic viewfinder 43 via a high voltage generation circuit 42, and the electronic viewfinder 43 is configured to display a subject image on its screen.

On the other hand, the recording system circuit includes a pre-emphasis circuit 48 that performs a predetermined frequency correction on the luminance signal Y+S of the signals synthesized by the encoder 40, and a luminance signal Y output from the pre-emphasis circuit 48.
The FM modulation circuit 50 that performs FM modulation on +S and the color difference signal R- of the signals synthesized by the encoder 40
A line sequential circuit 52 that converts Y and B-Y into line sequential color difference signals, a pre-emphasis circuit 54 that performs predetermined frequency correction on the line sequential color difference signals output from the line sequential circuit 52, and An FM modulation circuit 56 that performs FM modulation of line-sequential color difference signals and a predetermined format for recording photographic data (for example, recording photographic data at approximately 200 KHz).
a differential phase shift keying (DPSK) circuit 58 for recording according to the frequency of a mixer 59 that mixes three signals: the FM line sequential color difference signal output from the DPSK circuit 58 and various data signals output from the DPSK circuit 58 to create an FM video signal for recording; It consists of a preamplifier 86 that sets the FM video signal to a predetermined level, and a magnetic head 64 that records the FM video signal output from the preamplifier 86.

The preamplifier 86 is described as having two components, a recording amplifier and a reproducing amplifier, which will be described later, and performs a switching operation in response to a gate signal output from the gate circuit 84 for a predetermined period.

The magnetic head 64 is movable in the radial direction along the recording surface of the magnetic disk 66 by a head drive motor 62, as conceptually indicated by a dashed line 65. The head drive motor 62 has a control circuit 8.
The motor drive circuit 60 operates in response to an 8-bit motor drive signal output from the motor drive circuit 60, which operates four phases A, B, B, for 1-2 phase excitation.
A driving pulse of B is given. The moving direction of the magnetic head 64 is determined by the head drive motor 62 and the rotation direction, and the moving distance of the magnetic head 64 is proportional to its rotation angle. For example, the head drive motor 62
Each shift pulse causes head drive motor 62 to rotate approximately 18 degrees, thereby moving magnetic head 64 approximately 5 .mu.m. Therefore, 20 shift pulses result in a transfer of 100 μm (1 track).

A home position HP is provided on the outermost side of the magnetic disk 66. This home position HP is not attached to the magnetic disk 66, but is an extreme position assigned on the movement path of the magnetic head 64. home position
HP is detected by the home position switch. The movement of the magnetic head 64 from the outer circumferential side of the magnetic disk 66 toward the inner circumferential side is forward feeding, and the movement in the opposite direction is called reverse feeding.

On the other hand, the magnetic disk 66 is connected to the spindle motor 7
It is removably attached to the rotating shaft 68 of Steady rotation.

The PG detection coil 74 detects the magnetic disk 66 and the magnetic PG yoke (not shown) embedded in the rotating shaft, and the PG yoke (not shown) is obtained as a result of the detection.
The PG signal is inputted through the waveform shaping circuit 76 to the servo control circuit 78, gate circuit 84, and timing pulse generation circuit 26, respectively.

The gate circuit 84 outputs a gate signal to the preamplifier 86 based on the PG signal detected by the PG detection coil 74 and the recording/reproduction command signal output from the control circuit 82.

When the power switch SW3 is closed, power is supplied to the aperture drive circuit 20, and the aperture 12 is driven and controlled, and the solid-state image sensor 18 is also driven.

Further, power is supplied to the preamplifier 32, process circuit 34, gamma correction circuit 36, matrix circuit 38, encoder 40, high voltage generation circuit 42, electronic viewfinder 43, etc., and as a result, the electronic viewfinder 43 monitors the subject image. You will be able to do this.

Spin motor 70 is power switch SW3
After the shutter release button 90 is closed, the shutter release button 90 is activated. That is, the shutter release button 9
In this embodiment, the switch SW1 is closed in the first stroke of the pushing operation, and power is supplied to each circuit section of the recording system including the motor drive circuits 60 and 80. As a result, the servo control circuit 78 outputs a drive signal for driving the spindle motor 70 to the spindle motor 70 via the motor drive circuit 80. Furthermore, in the second stroke of pressing the shutter release button 90, the switch is released.
2 is closed, whereby the control circuit 82 controls the operations of each circuit section to perform shutter release, photographing, and recording. With this configuration, it is possible to avoid wasting power from a power source such as a battery.

FIG. 2 shows an example of the operation timing of the power switch SW3 and the release switches SW1 and SW2. In the figure, power switch SW3 is activated at time t1.
If operated with , then release button 9
The release switch SW1 is turned on at the first position of the 0 push operation, that is, at time t2, and is further turned on at the second stroke of the release button 90, that is, at time t3. And from time t2 to time T2
If you release your hand from the release button 90 at the elapsed time (time t4), the release switch SW will release at time t4.
2 becomes OFF, and then at time t5, that is, when time T1 has elapsed from time t2 when release switch SW1 was turned ON, the release switch SW is turned OFF.
1 is in the OFF state.

Further, 88 is an envelope detection circuit, and the envelope detection circuit 88 performs envelope detection on the reproduced FM video signal outputted through the preamplifier 86 and outputs the detection output to the control circuit 82. The control circuit 82 is based on this envelope detection circuit 8.
Based on the detection output of 8, a track search is performed to check the presence or absence of recording on each track of the magnetic disk 66, or a determination is made as to the presence or absence of a dropout that has occurred on the magnetic disk 66.

The NTSC video signal outputted from the encoder 40 passes through a high voltage generation circuit 42 and is visualized by an electronic viewfinder 43, and after passing through a buffer amplifier 46, is outputted to the outside via a video signal output terminal T1.

The control circuit 82 is a circuit that integrates and controls the operation of the entire device, which is equipped with a memory device such as a ROM in which various interfaces and control programs are stored. Various controls are performed based on a continuous shooting speed setting switch 92 for setting the shooting speed), a switch group 93 for instructing the number of frames to be taken during continuous shooting, or the form of shooting and recording. The control circuit 82 is also provided with a frame counter that counts the number of frames taken in the continuous shooting mode, and is also provided with a memory such as a RAM that stores the number of unrecorded tracks on the magnetic disk 66, that is, the number of frames that can be shot. It is being

Furthermore, an auto power-off timer is provided in the control circuit 82 to automatically turn off the power if no relay operation is performed for a certain period of time after the power is turned on. Additionally, various timers are provided that are activated based on the release operation. These timers are the first timers that start supplying power to each circuit section that performs photographing and recording operations when the release operation is performed, and maintain the power supply to each circuit section for a certain period of time even after the release operation is canceled. A timer, a second timer that maintains the supply of power to each of the above circuit sections by the release operation, and continues to maintain the power supply until the shooting/recording operation is completed; Supplying power to each of the circuit units for a certain period of time, and after the supply of power is completed, starting supplying power to each of the circuit units a predetermined time before the start of the photographing/recording operation, and photographing/recording the power supply state. It consists of a third timer that holds until the sequence control operation is completed.

The continuous shooting speed setting switch 49 also has 8 contacts (contacts a, b, c, d, e,
f, g, h) are provided, and the number of frames to be photographed per predetermined time is determined according to the selection of the contact point. In this embodiment, for example, by selecting contact a, shooting is performed at 15 frames/second, and thereafter, by sequentially selecting contacts b to contact h, shooting is performed at 10 frames/second (contact b), 5 frames/second ( Contact c), 2 frames/second (contact d), 1 frame/second (contact e), 1 frame/2 seconds (contact f), 1 frame/5 seconds (contact g), 1
Each frame/10 second (contact point h) is set to be photographed.

The key group 93 includes, for example, a shooting mode selection switch 94 that selects a single shooting mode in which the shooting operation ends for each frame, or a continuous shooting mode in which the shooting operation continues for a predetermined number of frames in a predetermined period of time, and a shooting mode selection switch 94 that selects a shooting mode in which the shooting operation is completed for each frame, or a continuous shooting mode in which the shooting operation is continued for a predetermined number of frames in a predetermined period of time. A recording mode switch 95 instructs field recording or frame recording of still images shot frame by frame, a shooting frame number setting switch 96 that sets the number of frames to be shot during continuous shooting, and a shooting frame number setting switch 96 to increase or decrease the setting value for the number of shooting frames. It consists of an up/down switch 97 for giving instructions.
For example, the shooting mode selection switch 94 selects a single shooting mode when the switch is in the open state, and the continuous shooting mode is selected when the switch is closed, and the recording mode switch 96 selects the continuous shooting mode when the switch is in the open state. When field recording is in a closed state, frame recording is performed respectively.

The shooting frame number setting switch 96 is a push switch, and the up/down switch 97 is a contact UP switch.
If the number of shots setting switch 96 is switched to the DOWN side, the set value for the number of shots will increase. is configured such that the set value of is decreased. This set value of the number of frames to be photographed is displayed on a liquid crystal display device 98.

The self-timer switch 100 and the interval timer switch 102 are switches that respectively set the timer mode, and when the self-timer switch 100 is turned on, power is supplied to each circuit that performs shooting and recording operations after a certain period of time after the release operation. is supplied, and interval timer switch 1
When 02 is turned on, power is supplied to each circuit section that performs photographing and recording operations after a certain period of time has elapsed since the release operation.

Incidentally, reference numeral 99 is a buzzer for issuing a warning when there is no unrecorded track on the magnetic disk 66, that is, when the number of frames that can be photographed is zero.

In the above configuration, the shutter release button 9
When the release switch SW1 is turned on by operation 0, power is supplied to the circuit section for photographing and recording operations, as shown in FIG. At this time, when the release switch SW1 is turned on, the release switch SW2 is not turned on and the release switch is turned on.
When SW1 is turned on, the first timer is started, and the power supply to each circuit section is maintained for a certain period of time (300 ms) after the release switch SW1 is turned off. That is, the release switch
Even if SW1 is turned off, the release switch SW
After 1 is turned off, press the shutter release button 90
Since both release switches SW1 and SW2 may be turned on when the release switch SW1 is operated, the power supply is maintained for a certain period of time even after the release switch SW1 is turned off. Therefore, even if the release operation is once released and then immediately started, the photographing/recording operation can be performed reliably. Furthermore, when the release switch SW2 is turned on after the release switch SW1 is turned on, the second timer is activated, and the circuit sections are activated for a certain period of time even after the release switches SW1 and SW2 are both turned off. power supply is maintained. Therefore, even if the release operation is released, power is supplied to each circuit that performs shooting and recording operations until the sequence control operation related to shooting and recording is completed, so shooting and recording operations cannot be performed reliably. can.

Further, when the self-timer switch 100 or the interval timer switch 102 is turned on and the timer mode is set, as shown in FIG. 4, when the release switch SW1 is turned on, power is supplied to each of the circuit sections for a certain period of time. It is now possible to perform processes such as photometry. After that, when the release switch SW2 is turned on, the third timer starts, and after a certain period of time, the spindle motor 7
Power is supplied to each circuit section that performs photographing and recording operations, including the motor drive circuit 80 that drives the camera. This power supply is set by a third timer so as to continue until the sequence control operation regarding imaging and recording is completed. That is, in this embodiment, after the release switch SW2 is turned on and the power supply to each circuit section that performs shooting/recording operations is cut off, the sequence control operation related to shooting/recording starts, for example, 10 seconds later. When the spindle motor 70 is turned on, a margin of 1 second is set as the start-up time of the spindle motor 70, and each photographing/recording operation including the motor drive circuit 80 that drives the spindle motor 70 is performed 9 seconds after the release switch SW2 is turned on. It is set to start supplying power to the circuit section and to continue supplying power until the completion of the sequence control. Therefore, when the timer mode is set, power is supplied to each part before the sequence control related to photographing and recording is started, so that photographing and recording can be reliably performed according to the photographing mode.

〔Effect of the invention〕

As explained above, the electronic still camera according to the present invention includes a first timer that maintains power supply to each circuit section that performs shooting and recording operations for a certain period of time even after the release operation is released, and A second timer that starts supplying power to each of the circuit sections and continues supplying power until the sequence control related to shooting and recording is completed even if the release operation is released, and a second timer that starts supplying power to each circuit section and continues supplying power until the sequence control related to shooting and recording is completed when the timer mode is set. The configuration includes a third timer that starts power supply to each circuit section before the start of control and continues the power supply state until the sequence control is completed, so that shooting and recording operations according to the shooting mode can be performed. Power can be appropriately supplied to each circuit section.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of an electronic still camera according to the present invention, and FIG. 2 shows a power switch SW3, a shutter release switch SW1,
A timing chart showing an example of the operation timing of SW2, Fig. 3 is a timer chart to explain the operation of the first timer and the second timer, and Fig. 4 is a timing chart to explain the operation of the third timer. 62... Head drive motor, 66... Magnetic disk, 82... Control circuit, 88... Envelope detection circuit, 90... Release button, 92... Continuous shooting speed setting switch, 94... Shooting mode. Selection switch, 95... Recording mode switch, 96
... Shooting frame number setting switch, 97 ... Up-down switch, 100 ... Self-timer switch, 102 ... Interval timer switch.

Claims (1)

[Scope of Claims] 1. In an electronic still camera that rotates a rotating recording medium such as a magnetic disk and records a video signal representing a still image of a subject on the rotating recording medium, a timer that instructs sequence control operations in a timer mode. mode establishing means; operating means that operates in two strokes and instructs power supply to each circuit section in the first stroke and instructs photographing/recording operation in the second stroke; and the timer mode. A power supply control means takes in the output signals of the setting means and the operation means and controls the power supply to each circuit unit that performs photographing/recording operations. a first timer means that starts power supply to the circuit section and maintains the power supply to each of the circuit sections for a certain period of time even if the power supply instruction is canceled; a second timer means that maintains the power supply to each of the circuit sections and continues the power supply state until the completion of the photographing/recording operation; After the supply of power is completed, the supply of power to each circuit section is started a predetermined time before the start of the photographing/recording operation, and the power supply status is checked when the photographing/recording operation is completed. 1. An electronic still camera, characterized in that it has a third timer means for holding up to a certain time.