JPS58148570A - Video camera system - Google Patents

Abstract

PURPOSE:To attain a still image pickup in an arbitrary shutter speed, by performing the write from an image sensor to a storage means in a variable drive speed and performing an image pickup output in a reference drive speed. CONSTITUTION:The recording operation of a magnetic recording and reproducing section 20 is synchronized with the image pickup operation with a CCD image sensor 10 and the reproduction of the section 20 is performed in the normal drive speed. Then, even if the drive speed of the sensor 10 is changed, a reproduced output suitable to the regular system, i.e., the NTSC system is obtained from the section 20 at all times. Thus, in changing the drive speed of the sensor 10, the shutter speed of the sensor 10 is changed and the still image pickup is done in an arbitrary shutter speed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a video camera system having a function of storing imaging output from an image sensor, and particularly to a video camera system that enables still imaging with variable shutter speed.

Generally, in a video camera, the photoelectric conversion part of the image sensor is always irradiated with acupuncture light. By reading out the virtual image output obtained from the photoelectric conversion section at a predetermined repetition period, a video signal compatible with the desired standard vision system is output. It has a shutter function that uses the recovery cycle of reading out the image output as the actual shutter speed. For example, in an NTSC video camera 1, the shutter 30 is fixed at -second or 1 second.
Imaging is performed at a speed of 60.

By the way, when performing stealth photography of a moving subject, it is necessary to increase the shutter speed because the movement of the subject causes blur in the photographer, making it impossible to obtain a clear image. be. However, as mentioned above, in conventional video cameras, the shutter speed is fixed, so unless measures are taken, such as providing a flexible shutter mechanism with variable shutter speed in the optical system, arbitrary It is not possible to perform 4 groups at the shutter speed.

SUMMARY OF THE INVENTION Therefore, the present invention provides a video camera system with a new configuration that makes it possible to take still images at any shutter speed by effectively utilizing the shutter function by reading out the imaging output from the image sensor. It is.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings showing one embodiment.

The embodiment shown in FIG.
The present invention is applied to a video camera using a CCD image sensor 10 formed by a large coupled device.
It is equipped with a magnetic recording and reproducing section 20 that uses a rotating magnetic sheet 21 as a storage medium as a storage means for the imaging output read out from the image sensor, and the operating speed of the CCD image sensor 10 and the magnetic recording and reproducing section 20 can be variably controlled. The drive control section 30 is equipped with a drive control section 30 that synchronizes the imaging operation by the CCD image sensor 10 and the recording operation of the magnetic recording and reproducing section 20 that records the imaging output from the CCD image sensor 10 to achieve an arbitrarily variable drive speed. By performing the reproducing operation of the magnetic recording/reproducing section 20 at a driving speed of a standard compatible with a desired standard television system, for example, the NTSC system, the driving speed of the CCD image sensor 10 can be adjusted. A still image of the subject is captured on the screen of the monitor television receiver 40 at a corresponding shutter speed.

In this embodiment, the drive control unit 30 uses a reference system clock φVR corresponding to a vertical synchronization signal of the NTSC system.
Reference bus stem clock generator 31 that outputs EF
, a shutter speed controller 32 that outputs a control voltage corresponding to a desired shutter speed, and a voltage-controlled variable oscillator VCO whose oscillation period is variably controlled according to the control voltage from the shutter speed controller 32.
33, the reference system clock φVREF from the reference system clock generator 31 and the vC0
The variable system clock generator 34 is supplied with the oscillation output φVR of 33 and outputs a variable system clock according to the shutter speed set by the shutter speed controller 32. The variable system clock generator 34 has transfer locks φV□, φV2s for driving the CCD image sensor 10.
φH, a sampling pulse φsp for sample-holding the imaging output from the CCD image sensor 10 in the sample hold circuit 11, and a sampling pulse φsp for sample-holding the imaging output from the CCD image sensor 10 in the first process processing circuit 12, and an NTSC method for the imaging output from the CCD image sensor 10 in the first process processing circuit 12. A synchronizing clock φCKV for performing the process according to the process and a driving clock φVD serving as a reference for the recording operation speed of the magnetic recording/reproducing section 20 are output as variable system clocks.

The above-mentioned CCD image sensor 10 has a CCD-based transfer register provided with each light-receiving section S corresponding to each pixel of -image, as shown in FIG. 2, whose basic configuration is shown. A vertical transfer register is formed using COD to temporarily store signal charges for one image, in which signal charges proportional to the amount of imaging light obtained by the imaging unit 2 and each of the light receiving units S are transferred from the imaging unit 1. It consists of a storage section 2, and a signal escape section 3 formed by a CCD with a horizontal transfer register for discharging the signal charges for one image accumulated in the storage section 2 every one horizontal line.

In the imaging section 1 of the CCD image sensor 10, each light receiving section S is always irradiated with imaging light, and as shown in FIG. 3A, each light receiving section is Each signal charge accumulated in S is driven to be vertically transferred to the storage section 2 during the transfer period TTR by the transfer lock φ■1. Further, as shown in FIG. 3B, the storage section 2 stores the signal charges for one image source transferred from the imaging section 1 during the transfer period TTR by the transfer lock φv2 during the flight period TREAD. , is driven to vertically transfer one horizontal line every 1H of one horizontal scanning period. Further, the signal readout section 3 is driven to horizontally transfer signal charges for one horizontal line transferred from the storage section 2 every 1H by the transfer lock φH and output it as an imaging output.

That is, the above-mentioned CCD image sensor 10 is operated by the above-mentioned variable system clock so that the imaging output obtained by capturing an object image at a shutter speed corresponding to the above-mentioned imaging period 1%'lTs is read out every 1 V during one field period. It is driven by drive clocks φv1, φv2, and φH from the generator 34, and performs a frame transfer type imaging operation.

The CCD image sensor 10 has a transfer lock φvl l from the variable system clock generator 34.
When φv21φ■ is synchronized with the reference system clock φVREF, the imaging operation is performed at a shutter speed compatible with the normal NTSC system, that is, the shutter speed of the NTSC system, and the shutter speed controller 32 controls the oscillation of the VC033. By controlling the output φVR and varying the one-field period 1V, the imaging period Ts for providing the shutter speed can be arbitrarily controlled.

The imaging output read from the CCD image sensor 10 is supplied to the first process processing circuit 12' via the sample hold circuit 11. The sample hold circuit 11 controls the CCD using the sampling clock φsp from the variable system clock generator 34.
The imaging output of the image sensor 10 is sampled and held. Further, the first process processing circuit 12 generates a composite video signal obtained by applying NTSC NTSC process processing to the imaging output using the synchronization clock φCKV supplied from the variable system clock generator 12. The signal is supplied to the magnetic head 22 of the magnetic recording/reproducing section 20 via the mode changeover switch 35.

The magnetic recording and reproducing section 20 includes a rotating magnetic sheet (21) which is rotationally driven by a motor 23.7. A magnetic head 22 for both recording and reproducing, which traces the recording track on the rotating magnetic sheet 21 and records and reproduces signals. The rotating magnetic sheet 2 is equipped with a rotating magnetic sheet 2 at a rotation speed (speed) synchronized with a system clock given from the drive control section 30 to a motor drive circuit 24 that controls the drive of the motor 23.
1 is rotatably driven. Here, the motor drive circuit 24 receives a reference system clock φV from each clock generator 31'', 34 of the drive control unit 30.
REF and drive clock φVD are selectively supplied via the second mode changeover switch 36, and during recording mode REC, the rotating magnetic sheet 21 is rotated at a rotation speed synchronized with the drive clock φVD. However, in the playback mode PB, the reference system clock φVRgF
The drive of the motor 23 is controlled so as to rotate the rotating magnetic sheet 21 at a rotation speed synchronized with the rotation speed. Further, the magnetic head 22 is connected to a first mode changeover switch 35, and in the recording mode, the imaging output supplied from the CCD image sensor 10 via the first process processing circuit 12 is transferred to the rotating magnetic sheet. 21, and in the reproduction mode, the reproduction output reproduced from the recording track of the rotating magnetic sheet 21 is transmitted to the reproduction amplifier 25.
and outputs a reproduced video output signal from the second process processing circuit 2i. The second global processing circuit 26 is supplied with the reference system clock φVREF from the reference system clock generator 31 as a synchronization clock, and processes the reproduced output from the magnetic head 22 according to the NTSC system. Apply processing.

In the embodiment configured as described above, the recording operation of the magnetic recording and reproducing section 20 is performed in synchronization with the imaging operation of the CCD image sensor 10, and the reproducing operation of the magnetic recording and reproducing section 20 is performed at the normal driving speed, that is, the vertical speed in the NTSC system. Since the driving speed is synchronized with the synchronization period IVN7sc, even when the driving speed of the CCD image sensor 10 is varied, the magnetic recording/reproducing section 20 can perform the N T
A playback output compatible with the SC system can always be obtained. Therefore, by varying the driving speed of the COD image sensor 10, the effective imaging period Ts of the CCD image sensor 10, that is, the negative speed, can be varied to perform stealth imaging at an arbitrary shutter speed. be able to. Note that the maximum shutter speed is determined by the limit value of the signal charge transfer speed in the COD image sensor 10.

In the above-described embodiment, the magnetic recording/reproducing unit 20 using the rotating magnetic sheet 21 as a storage medium is used as a storage means for image pickup output, and the reproduced image output signal is directly monitored by the monitor television receiver 40. However, the video signal recorded on the rotating magnetic sheet 21 of the magnetic recording/reproducing section 20 can be reproduced as is by a general NTSC type magnetic reproducing device. Further, the storage means may be of any type as long as it has a storage capacity to store the imaging output for at least one image, and a semiconductor memory or the like may also be used.

As is clear from the description of the embodiments described above, according to the present invention, there is provided a storage means having a storage capacity for storing at least one image's worth of imaging output read out from an image sensor, and the image sensor and the storage means are variable. and a drive means that drives at a drive speed, and synchronizes the imaging operation by the sensor and the writing operation of the image pickup output from the image sensor to the storage means, and at a variable drive speed. by performing the imaging output stored in the storage means at the standard 1-sho speed,
By adopting a video camera system characterized by performing imaging operation at a variable shutter speed that corresponds to the drive speed of the image sensor, it is possible to use an arbitrary shutter mechanism without providing an opportunistic shutter mechanism in the optical system. Therefore, it is possible to provide a video camera system capable of capturing still images at a shutter speed of 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a video camera system according to the present invention. FIG. 2 was applied to the above embodiment. FIG. 2 is a schematic plan view showing the configuration of a CCD image sensor. 3A and 3B are time charts showing the operation of the CCD image sensor, FIG. 3A shows the fabrication of the imaging section, and FIG. 3B shows the operation of the storage section. 10... CCD image sensor 20... Magnetic recording/reproducing unit (storage means) 21... Rotating magnetic sheet 22... Magnetic head 23... Motor 24... Motor drive circuit 30... Drive control Section 31...Reference system clock generator 32.
...Shutter speed controller 33...Voltage controlled variable oscillator 34...Variable system clock generator 40...
・Motor television receiver patent applicant Sony Corporation representative Patent attorney Akira Koike

Claims (1)

[Claims] The image sensor comprises: a storage means having a storage capacity for storing virtual image output for at least one stroke method sequentially outputted from the image sensor; and a driving means for driving the image sensor and the storage means at a variable driving speed. The virtual image operation by the image sensor and the writing operation of the virtual image output from the image sensor into the storage means are synchronized, and are performed at a freely variable drive speed, and the ts stored in the storage means is
By performing the driving speed based on the II ratio output standard,
A video camera system characterized in that an imaging operation is performed at a variable shutter speed corresponding to the driving speed of the image sensor.