JPS6361567A - Still video camera with consecutive photographing mode - Google Patents

Abstract

PURPOSE:To consecutively photograph at a high speed by outputting a release ready signal on the midway of the automatic exposure sequence, and allowing the acceptance of the shutter release signal for the following one-frame photographing. CONSTITUTION:During a time when the consecutive pickup mode is set, a main controller 30 informs an exposure controller 40 of that the check processing is ended, then controls a mirror 45 to start its action of inclining downward, as well as controls to start charging a shutter spring. The exposure controller 40 immediately outputs a release ready signal. On receiving the release ready signal, the main controller 30 receives an S2-on signal, and transmits a release signal Rs2 for a second frame to the exposure controller 40, and the controller 40 commands the mirror 45 to incline upward. Therefore, the action of the mirror 45 to incline upward/downward is executed continuously.

Description

[Detailed Description of the Invention] Summary of the Invention A main controller that performs control to write a still video signal captured by an imaging device onto a magnetic disk when a release signal of a shutter release switch is received, and a photometer. , aperture control, opening and closing of a shutter that is opened and closed by the biasing force of a spring.

An exposure control device is provided for controlling a series of exposure sequences including charge driving of a shutter spring.

The main control device and the exposure control device are synchronized by exchanging signals with each other. One of the signals for synchronization is a release ready signal output from the exposure control device. This is output when the exposure control device completes the above series of exposure sequences, and allows the main control device to accept a release signal from the shutter release switch.

However, when operating in continuous shooting mode, the time allowed for capturing one frame is limited, so the exposure control device outputs a release ready signal in the middle of the exposure sequence.

BACKGROUND OF THE INVENTION The present invention relates to a still video camera (electronic still camera) that photographs a subject with an electronic imaging device and records the still video signal on a magnetic disk. A main controller that performs control to write still/video signals captured by an imaging device onto a magnetic disk when a release signal is received, photometry, aperture control, and opening/closing of a shutter that is opened and closed by the biasing force of a spring. The present invention relates to a still video camera having a continuous shooting mode and an exposure control device for controlling a series of automatic exposure sequences including charging and driving of a shutter spring for the next shutter opening/closing.

The operation of the main control unit and the operation of the exposure control unit are both directed toward the main purpose of a still video camera, which is to take, photograph, and record still images, and they must work in conjunction with each other. It is configured to achieve synchronization by exchanging signals between the two. One of the signals for synchronization is a release ready signal output from the exposure control device. This is what the exposure control device outputs when it completes the above exposure sequence.
This allows the main controller to accept a release signal from the shutter release switch. This release ready signal can be said to be a signal that allows the shooting of one frame to be completed and to move on to the shooting of the next frame.

The operation of still/video cameras in continuous shooting mode is as follows:
While the shutter release button is pressed, images of the subject are captured at regular intervals and the still video signals are sequentially recorded on each track of the magnetic disk. For example, in continuous shooting (continuous shooting) at 10 frames/second, the subject is imaged and recorded every 1/10 second.

Among the operations of each part controlled by the main controller during the shooting of one frame, the main operations that take a relatively long time include recording the still video signal onto the magnetic disk (required time: 1/Go seconds, the same applies hereinafter). .

Checking the recorded video signal (1/60 seconds).

Transferring the magnetic head to the next unrecorded track (approximately 3/60
seconds). These operations alone take about 5/60 seconds, so in order to complete the photographing operation of the piece in 1/lo seconds (-6/Go seconds), the time remaining for other operations is approximately 1/6.
It is 0 seconds.

Similarly, among the operations controlled by the exposure control device when photographing one frame, the relatively time-consuming operations are: A
ll+ light and aperture control based on this (approximately 2.5/
00 seconds), shutter opening/closing (approximately 1/250 to 1/60 seconds), and motor drive to charge the shutter spring (approximately 3/60 seconds).
/10 (-6/60) <It will take a long time.

Since some of the operations of the main control device g and some of the operations of the exposure control device are performed in parallel, the sum of the above times does not necessarily equal the time required to shoot one frame. It is extremely difficult to process one frame in 1/10 seconds in order to achieve continuous shooting at 0 frames/second.

SUMMARY OF THE INVENTION An object of the present invention is to ensure synchronization of the operations of the main control device and the exposure control device, and to allow the operations of both devices to be performed in parallel as much as possible, thereby achieving high-speed continuous shooting.

A still video camera with a continuous shooting mode according to the present invention reads out still video signals stored in an imaging device when receiving a release signal from a shutter release switch.

A series of automatic controls including a first control device that controls the writing of still video signals to a rotating magnetic disk, photometry, aperture control, opening and closing of a shutter that is opened and closed by the biasing force of a spring, and charging drive of a shutter spring. A second control device for controlling the exposure sequence and continuous shooting mode setting means are provided.

The first control device has a control means that accepts a release signal of the shutter release switch on the condition that a release ready signal is input from the second control device. On the other hand, the second
At least when the continuous shooting mode is set, the control device controls the release-ready signal generation means for sending a release-ready signal to the first control device during the automatic exposure sequence and at least after opening and closing the shutter. It is characterized by the fact that it is

Most preferably, after opening and closing the shutter under the control of the second control device, the still video signal stored in the imaging device under the control of the first control device is read out;
When the writing of this video signal to the magnetic disk ＼ is completed, or if the camera has a function to check whether the writing has been done correctly, when this checking process is completed, the second control unit It is preferable to output a release ready signal. Second control M IM
Then, in order to photograph this one frame of carburization, the charging drive of the shank spring, photometry, and aperture control will be performed.
The control device will similarly move the magnetic field to the next unrecorded track for the next frame of photography.

1', Description 2 In a still video camera which is controlled up and down by a control device and is equipped with a mirror for deflecting an incident light image to a viewfinder, the release ready signal generating means of the second control device is Preferably, at least when the continuous shooting mode is set, the release ready signal is output immediately after the mirror starts to move down. As a result, the down operation and subsequent up operation of the mirror are performed continuously.

Even when the continuous shooting mode is not set, the release ready signal may be output during the automatic exposure sequence, or after the automatic exposure sequence is completed.

In this way, in the present invention, the release ready signal is output in the middle of the automatic exposure sequence.

Acceptance of the shutter release signal for the next frame of photography is permitted, and from this time the operation for the next frame of photography can be started, reducing the time required to photograph each frame. This makes high-speed continuous shooting possible.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 schematically shows part of the electrical configuration of a still video camera having a continuous shooting mode.

The rri1 disk 11 is housed in a disk pack that rotatably accommodates it. The still video camera is provided with a bucket that can be opened and closed, and a disk pack is inserted into the opened packet, and when this packet is then closed, the magnetic disk 11 is transferred to the spindle of the disk motor 14. Gets chucked.

A plurality of (for example, 50) tracks (for example, a track pitch of 100 μm) are provided concentrically on the magnetic disk 11, and are formed by photographing processing.

One field or one frame (l frame) of FM-modulated color video signals (including an Ili degree signal, one color difference signal, etc.) are magnetically recorded on each track.

The 50 tracks arranged concentrically on the magnetic recording surface of the magnetic disk 11 are numbered in order from the outside.
Track numbers 1 to 50 are assigned. Home position HP (origin position or standby position)
is located outside the No. 1 track, and the end position EP is located at the inner extension 1 of the No. 50 track.

The main controller 30 controls the operation of each part of the still video camera except for the parts related to exposure such as the diaphragm, mirror, and shutter, which will be described later, and the overall operation. This main control device 30 is composed of a central processing unit, preferably a microprocessor (hereinafter referred to as CPU), a memory that stores its programs and necessary data, and an interface with each peripheral element circuit, device, etc. ing.

A magnetic disk 2 for writing a still video signal of an imaged object onto a predetermined track of the magnetic disk 11 is supported movably in the radial direction of the magnetic disk 11 by its transfer drive control device and is transferred in the same direction. controlled. The main controller r; qao gives instructions regarding the transfer direction and transfer of the magnetic head 21 to this transfer drive control device. The magnetic head transfer drive control device & includes a step motor 22 and its drive circuit 23, and the magnetic head 21 is transferred in proportion to the rotation angle of the step motor 22. For example, each driving pulse of the step motor 22 rotates the motor 22 by about 15 degrees, thereby moving the magnetic head 21 by about 4.2 μm. therefore.

The transport of the magnetic head 21 is carried out with great precision.

In order to improve the contact between the magnetic head 21 and the rotating magnetic disk 11, a regulating member (not shown) is provided on the opposite side of the magnetic head 21 with the magnetic disk 11 in between. Further, the core of the magnetic disk 11 is equipped with a magnetic disk 11 that detects the leakage magnetic flux of the permanent magnet for chucking.
A phase detector [2 is located nearby, which outputs a phase detection signal when the angle reaches a predetermined angular position. This much F eye detector 12
The output detection signal is waveform-shaped by a waveform shaping circuit 13 and outputted as a position output pulse PG. Phase detection pulse P
One C is generated every rotation of the magnetic disk 11. This phase detection pulse PG is the servo control circuit 1
7. Switching control circuit 25. The signal is sent to main controller 30 and clock signal generation circuit 60.

Disk motor 14 is driven by its drive circuit 16. The number of rotations of the disk motor 14 is detected by a frequency generator I5, and a detection signal with a frequency proportional to the number of rotations of the motor 14 is input to the servo control circuit 17. The servo control circuit 17 receives a reference frequency signal input from the clock signal generation circuit 60, a frequency detection signal input from the detector 15, and a position Ill detection pulse PG from the circuit 13.
Based on
Rotate at a constant speed of 100r, p, m,).

The rotational phase is also controlled so as to be synchronized with the pulse PG. Also the servo control circuit 17. The motor 14 is started and stopped in accordance with commands from the main controller 30.

The reproducing/recording switching/amplifying circuit 24 is normally set on the reproducing side, and amplifies the FM variable and ring video signals read by the magnetic head 21. This amplified video signal is sent to envelope detection circuit 26. This reproduced video signal is used for track search processing, checking processing, and the like. On the other hand, the video signal representing the still image of the photographed subject is processed by the recording signal processing circuit described later.
After various processing including modulation and the like is applied, the signal is input to the reproduction/recording switching/amplification circuit 24. The main controller 30 is 5
When the self-recording command REC is output, the switching control device 25 switches the circuit 24 to the recording side at the timing of the input phase detection pulse PG. Then, the signal-processed video signal is amplified by this circuit 24 and then applied to the magnetic head 21, and the still video signal is recorded on a predetermined track of the magnetic disk 11. This record is on magnetic disk 1
This is done only during one revolution of 1. That is, the control circuit 25 switches the circuit 24 to the recording side only during one period of the pulse PG.

The envelope detection circuit 26 is a detection circuit that detects the read signal of the magnetic head 21, that is, the envelope of the FM modulated video signal recorded on the trunk of the magnetic disk 11, and outputs a voltage signal corresponding to the envelope. It is. The voltage signal representing the envelope is analog-to-digital converted into an 8-bit digital signal representing a quantization level of, for example, 25G and then sent to the main controller 30.
Enter.

The envelope detection signal is used by the main controller 30 to determine whether a track on the magnetic disk 11 is unrecorded or recorded (track search process).

If the level of the detected signal does not reach a predetermined threshold level when the magnetic head 21 is moved across a track, that track is unrecorded, and if it has reached the threshold level, then The track has already been recorded. The envelope detection signal is also used in the recording check process. What is record check processing?
After the photographed still video signal is recorded on a predetermined track by the magnetic head 21 as described above, it is checked whether this recording has been performed correctly. If so, it is determined that recording has taken place.

This still video camera has a single-shot mode in which one frame of still images is recorded on the magnetic disk 11 each time the shutter release button 31 is pressed, and a single-shot mode in which one frame of still images is recorded on the magnetic disk 11 each time the shutter release button 31 is pressed. There is a continuous shooting mode in which one frame is photographed at fixed time intervals (for example, 1/10 seconds) and the methyl images are sequentially recorded on each track of the magnetic disk 1. A single shooting mode switch 32 and a continuous shooting mode switch 33 are provided to select these modes. Only a continuous shooting mode selection switch is provided,
If this switch input is not made, the LLI photography mode may be automatically set.

The shutter release button 3I is of a two-stage stroke type, in which the first stage of depression releases switch S1, and the second stage of further depression of button 31 causes switch S2.
are respectively turned on. When the switch S1 is turned on, main power is applied to each part and the disk motor 14 is driven. Thereafter, when the switch S2 is turned on, a photographing operation is started as described later.

The imaging optical system includes an imaging lens system 43 including an afocal lens, a mask lens, etc. for forming a subject image.
．． Aperture 44. Shutter 46. It is composed of a mirror 45 and the like for reflecting a subject image onto a viewfinder 47 including a penta prism.

Further, a photometric element 48 for detecting the illuminance of incident light, such as a non-recon photodetector, is provided, and a portion of the light split from the imaging lens system 43 is configured to be incident on this element 48. The illuminance detection signal from the photometric element 48 is input to the exposure control device 40 .

The exposure control device 40 calculates the aperture value and shutter speed based on the incident light illuminance detected by the photometric element 48, controls the aperture 44 based on the determined aperture value,
Similarly, based on the determined shutter speed, opening/closing control of the shutter 46, raising/lowering control of the mirror 45, etc. are performed. This exposure control device 40 also. It consists of a CPU, memory, interface, etc.

The main control device 30 and the exposure control device 40 are connected by a bus, and their CPUs operate synchronously while exchanging control signals, data, etc. with each other. One of the typical signals sent from the exposure control device 40 to the main control device 30 is a release ready signal, and conversely, one of the signals sent from the device 30 to the device 40 is a release signal R82. The synchronized operation of these devices 30 and 40 will be described later.

Shutter 4G is a focal plane shutter,
It has springs for running the first and second curtains. These springs are pre-charged (i.e. extended by pulling in the case of tension springs) so that they can exert their biasing force? The shutter is opened and closed by releasing the latch using eight magnets.

Such charging of the spring of the shutter 46 is performed by a drive motor included in the agitating device 42. This drive device 42 further drives the energization of the electromagnet of the shutter 46, the up/down of the mirror 45, and the like. Aperture 4
Adjustment of the amount of aperture 4 is performed by another drive device 41 including a drive motor. These drives 41.4
2 is controlled by the exposure control device 40 as 11. be controlled.

The clock signal generation circuit 60 generates clock pulses of several different frequencies, high and low, and is connected to the servo control circuit 1 described above.
7. Main controller 30. and DPSK (Dirf'er
ential PI+ase 5hlrt Keyin
g ; Differential position shift change, "I!l)" is sent to the circuit 57. This phase circuit 6o also receives the input phase detection pulse P.
In synchronization with G, vertical and horizontal synchronizing signals for one field scan are generated during one cycle of pulse PG. These synchronization signals are sent to a vertical synchronization drive circuit 61 and a horizontal synchronization drive circuit 62, respectively.

At the focal plane of the Jn f& optical system, a three-primary solid-state imaging device (indicated overall by 50), which is a two-dimensional imaging cell array such as a COD, is arranged. R (red), G (green), and B (blue) filters are provided in front of the imaging device for each primary color. The video data stored on these imaging devices when the shutter 46 was opened.

The above synchronous drive circuit 61. , 82 drive the imaging device, serial still video signals (R, G
, B), and the preamplifier circuit 51. The signals are input to a process matrix circuit 53 through variable gain amplifier circuits (color balance adjustment circuits) 52, respectively. This circuit 53 generates a luminance signal Y and two color difference signals RY and BY. These color difference signals R-Y and B-Y are then line-sequentialized for each IH in a line-sequentialization circuit 54. The luminance signal Y and the line-sequential color difference signal are sent to a pre-emphasis circuit 5.
5 and are FM modulated in different frequency bands (FM modulation circuit 56). On the other hand, data other than the video signal output from the main controller 30 is modulated by the DPSK circuit 57, combined with the two series of FM modulated video signals by the combining circuit 58, and then sent to the reproduction/recording switching/amplification circuit 24. When the recording side is switched, this FM-modulated and synthesized still video signal for one field is recorded on a predetermined track of the magnetic disk 11 by the magnetic head 21 during one rotation of the magnetic disk 11. As mentioned above.

Now, the imaging and recording operations in the single-shot mode will be explained with reference to the time chart 11a in FIG. In FIG. 2, VD is a vertical synchronizing signal, and its one period (i.e. I
V+V is the vertical scanning period) is 1/60 second in this embodiment. Further, this signal VD is delayed by 7H from the output pulse PG (H is the horizontal scanning period). shutter 4
It is assumed that the charging of the spring 6 has been completed and a release ready signal has been sent from the exposure control device 40 to the main control device 30.

Main controller 30 receives a release signal from shutter release switch 31 (on signal of switch S2) when a release ready signal is input.

If this release ready signal is not input, the exposure sequence has not finished, so even if the switch S
2 is turned on, this on input signal is ignored.

When the main control device 30 receives the human power to turn on the switch S2, this device 30 immediately sends the release signal R82 to the exposure 1
;1j is sent to the control device 40. Then, the exposure control device 40 stops outputting the release ready signal and starts the exposure sequence. That is, while raising the mirror 45 through the drive device 42.

The photometric illuminance of the first element 48 is read to determine the aperture value and shutter speed, and the aperture control is performed through the drive device 41 based on the determined aperture value.

When the photometry and aperture control are completed, the shutter 4G is opened and closed through the drive device 42 based on the determined shutter speed.

When the exposure control device 40 notifies the main control device 30 that the shutter 4B has been opened or closed, the primary vertical synchronization signal VD
In one cycle, the photographed still video signal is recorded on the magnetic disk 11, and the above-mentioned recording check process is performed in the next cycle. Main controller η30
On the other hand, an operation is started to transfer the magnetic heads 2 and 1 to the next unrecorded i-rank for the primary photographing.

When the main controller 30 transmits to the exposure control device 40 that the record check process has finished, the exposure control device 40
On the side, the mirror 45 is moved down by the drive device 42, and the spring charging operation of the Nyatta 4G is started in preparation for the next shutter opening/closing.

When the spring charge ends, the exposure sequence ends. This causes the Ffl 1i11 gJ device 40 to
Since a release ready signal is output, tertiary photography becomes possible.

As can be seen from FIG. 2, in the single-shot mode in this embodiment, it takes 9V (9/60 seconds) to photograph and record one frame. For example, in order to perform continuous shooting at 1° frame/second, the time allowed for shooting and recording one frame is 6V (
6/6 (1 second). Therefore, in the continuous shooting mode, the release ready signal is output in the middle of the exposure sequence.

The operation when the continuous shooting mode is set is shown in FIG. Mirror close-up of the first frame.

Light metering, aperture control, shutter opening/closing, recording, and check processing are the same as in single-shot mode. When the main control device 30 notifies the exposure control device 40 that the check process has ended, the control device 4o starts moving the mirror 45 down and starts charging the shutter spring. Further, the exposure control device 40 immediately outputs a release ready signal. In continuous shooting mode, shutter release,
Since the button 31 remains pressed, the main controller 30 immediately releases the 8
2 ON signal is received, and a release signal R82 for the second frame is sent to the exposure control device 40. When the exposure control device 40 receives this signal R3°, it stops outputting the release ready signal and instructs the mirror 45 to move up. Therefore, the up command is given to the drive device 42 before the down operation of the mirror 45 is completed, so that the down and up operations of the mirror 45 are performed continuously. When the release signal R8□ of the second frame 11 is activated, the exposure control device 4o also performs photometry and aperture control. The exposure sequence for the first frame and the exposure sequence for the second frame overlap here.

When the 1ill+ light and aperture control in the exposure sequence for the second frame is completed, and the exposure sequence for the first frame is completely completed, the shutter is opened and closed to take the second frame, and then the main control Below, under the control of the device 30,
A check process is performed. In the continuous shooting sequence, a series of operations like this are performed continuously.

The release φ ready signal may be output at any time after the shutter 04 is closed. The charging operation of the shutter spring may also be performed immediately after opening and closing the shutter.

However, 6! It is preferable that the drive devices 41 and 42 are not operated during the recording process of the still video signal onto the magnetic disk 11 by the optical head 21 and the checking process of this recording. These drives 41.4
Driving a motor or other power source in the 2nd class causes 1st mechanical vibration. Since the battery built into a methyl video camera has a small capacity, the power supply voltage tends to fluctuate due to the drive of the power source, and noise tends to occur.

This is because there is a risk that an error will occur if recording or checking processing is performed during this time.

Note that the release ready signal may be output in the middle of the exposure sequence even in the single-shot mode.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the electrical configuration of the still video camera, Fig. 2 is a time chart showing the operation in the t-shot mode, and Fig. 3 is a time chart showing the operation in the continuous shooting mode. It is. 11...Magnetic disk. 21...Magnetic head. 30... Main control device. 40... Exposure control device. 4I... Aperture drive device. 42...Mirror, shutter drive device. 44...Aperture. 46... Nyatta. 33... Continuous shooting mode switch. that's all

Claims (2)

[Claims] (1) When a shutter release switch release signal is received, the first one reads out the still video signal stored in the imaging device and controls the writing of the still video signal onto the rotating magnetic disk. a second control device for controlling a series of automatic exposure sequences including photometry, aperture control, opening and closing of a shutter opened and closed by the biasing force of a spring, and charging drive of a shutter spring;
and continuous shooting mode setting means, and the first control device controls the release signal of the shutter release switch on the condition that a release ready signal is input from the second control device. the second control device transmits a release ready signal to the first control device during the automatic exposure sequence and at least after the shutter is opened and closed, at least when continuous shooting mode is set; A still video camera with a continuous shooting mode that has means for generating a release ready signal. (2) In the mirror which is controlled up and down by the second control device and is provided with a mirror for deflecting an incident light image to the viewfinder, the release ready signal generating means of the second control device is at least connected to the When the photographic mode is set, a release ready signal is output immediately after the mirror starts to move down, whereby the down operation and subsequent up operation of the mirror are performed continuously. Claim No. 1
Still video camera with continuous shooting mode as described in ).