JPH0246078A - Image pick-up device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an imaging device, and more specifically, to an imaging device capable of obtaining still image signals with high vertical resolution.

[Conventional technology]

Various imaging devices have been developed and commercialized for television signals, but most of them are NTSC, PAL, and SE.
Since it is designed in accordance with the television format such as CAM, it does not have sufficient vertical resolution. That is, N.T.
In the SC system, the vertical resolution is approximately 480 lines, PAL, S
In the ECAM method, there are approximately 560 lines.

On the other hand, with the spread of video-related technology, applications such as printing still images on paper from video signals are emerging.For example, when a resolution of 16 lines/dragon is required, conventional NTS
When a C-type imaging device is used, there is a problem in that it can only be realized with a size of about 31 cm vertically. Also, of course, if the size is forcibly enlarged, the roughness of the image becomes noticeable.

Also, electronic still cameras and 172-inch VTR-type integrated movie cameras are known as configurations that integrate an imaging device and an image recording device that records the video signal output thereof. The imaging devices or video cameras used in these devices also output television-type video signals.

[Problem to be solved by the invention]

As described above, since conventional imaging devices output video signals that comply with television standards, they are insufficient in terms of vertical resolution, and in particular, it is not possible to obtain images of sufficient image quality. .

Therefore, an object of the present invention is to provide an imaging device that can obtain an image signal with high resolution in the vertical direction.

[Means to solve the problem]

An imaging device according to the present invention includes a photographing optical system, a dividing means for dividing an optical image formed by the photographing optical system into two systems, and first and second imaging means for photoelectrically converting the two optical images formed by the dividing means. , a driving means for synchronously driving the first and second imaging means, and the first imaging means and the second imaging means are arranged at a distance of 1/1 in the vertical direction in an optically equivalent plane.
They are arranged two pixels apart, and on the imaging surfaces of both image sensors, a shielding mask that extends horizontally with a pitch of one vertical pixel and a width of about 172 vertical pixels is arranged. Features.

[Effect]

By arranging the first imaging means and the second imaging means in the above-mentioned positional relationship and providing the above-mentioned shielding mask, the output of the first imaging means and the output of the second imaging means become complementary to each other, By using one output as the first field and the other output as the second field, a high-quality video signal can be obtained.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a configuration block diagram of an embodiment in which the present invention is applied to a camera-integrated image recording device. However, to simplify the explanation, NTSC monochrome video will be taken as an example.

In Fig. 1, IO is a photographing lens, 12 is a half mirror, and 14A is a first lens that outputs an NTSC standard video signal.
The image sensor 14B is similar to the first image sensor 14A,
A second image sensor that outputs an NTSC standard video signal, 1
6A and 16B are drive circuits that drive the image sensors 14A and 14B, respectively. The image sensors 14A and 14B are arranged on optically equivalent planes, although the details will be described later.

In this embodiment, the same signal processing channels (A channel and B channel) for recording are provided for each of the first image sensor 14A and the second image sensor 14B,
18A, 18B are process circuits, 20A, 20B are emphasis circuits, 22A, 22B are clamp circuits, 24A
, 24B is an FM modulation circuit, 26A, 26B is a recording magnetic head selection switch, 28A, 28B: 30A, 30
B is a recording amplifier, and 32 is a multichannel head. The multi-channel head 32 includes four magnetic heads 32-1, 32-2, 32-3, and 32-4.

34 is a magnetic sheet as a magnetic recording medium, 36 is a center core, 38 is a motor that rotates the magnetic sheet 34, 40 is a PG pin attached to an eccentric position of the center core 36, and 42 is a PC pin 40 that detects 44 is a PG detection circuit; 46 is a servo circuit that controls the rotational speed of the motor 38 to a predetermined value; 48 is a system controller that controls the entire system; 50 is a drive circuit 16;
A, 16B, the clamp circuits 22A, 22B, and the servo circuit 46 are clock generating circuits that supply a clock serving as an operating reference.

Next, the operation shown in FIG. 1 will be explained. The object light transmitted through the photographic lens 10 is divided into two parts by a half mirror 12, and the light is divided into two parts by the first and second image pickup elements 14A and 14B, respectively.
The two image sensors 14A and 14B which form an image on the drive circuit 16A and 14B follow the clock from the clock generation circuit 50.
It is synchronously driven by 6B. Therefore, both image sensors 1
4A.

The video signals output from 14B are synchronized with each other. The process circuits 18A and 18B have gamma correction (r
=0.45), a composite synchronization signal is added, and the signal is applied to the emphasis circuits 20A and 20B. Emphasis circuits 20A and 20B are subjected to known emphasis processing, and clamp circuit 22A.

At 22B, a known clamping process is performed. Also, FM
For example, the modulation circuits 24A and 24B comply with the still video format (EIAJ) and have a sync chip of 6M.
I(z) performs FM modulation with a white peak of 7.5 MHz.

The outputs of the FM modulation circuits 24A and 24B are connected to a switch 26A,
26B and recording amplifier 28A, 30B; 28B, 30B
The signal is applied to the multi-channel head 32 via the multi-channel head 32 and recorded on the magnetic sheet 34.

Switches 26A and 26B are system controller 48
The recording amplifiers 28A, 30B; 28B, 30B are controlled to be in operation by a recording gate signal 50, 51 from the system controller 48, and each of the recording amplifiers 28A, 30B; Apply a recording current to the corresponding head.

FIG. 2 shows a timing chart of the recording operation. Second
(1) shows the output of the image sensor 14A, (2) shows the output of the image sensor 14B, and (3) shows the 60 Hz (NTSC) vertical synchronization signal V output from the clock generation circuit 50.

, (4) are PG pulses output from the PC detection circuit 44. This PG pulse indicates the rotational phase of the magnetic sheet 34, and is formed by the PG detection coil 42 detecting the magnetism by the PG pin 40, and the PG detection circuit 44 amplifying and shaping the output of the PG coil 42. The servo circuit 46 compares the phase between the vertical synchronization signal vs and the PG pulse, and controls the motor 38 so that this phase difference becomes a predetermined value. Therefore, the PG pulse and the vertical synchronization signal V
, a constant phase relationship is maintained between them. By the way,
In the above-mentioned still video format (EIAJ), the vertical synchronization signal V is 7±2H (H indicates the horizontal synchronization period).

) is maintained such that the PG pulse is located before the PG pulse. By keeping the phase relationship constant, the recording position of the signal on the recording track on the magnetic sheet 34 can be kept constant.

In this way, after the predetermined phase relationship is established, when the system controller 48 receives the recording command signal (FIG. 2 (5)) from the operation switch (not shown), the system controller 48 receives the recording command signal (FIG. 2 (5)). As shown in 6), a switch changeover control signal 49 is applied to the switches 26A and 26B in response to the PG pulse at the next timing of the recording command signal,
Switch to the a contact side.

Further, as shown in FIG. 2 (7), a recording gate signal 50 is applied to the recording amplifiers 28A and 28B for a period of one field in response to the PG pulse. Thereby, the output video signals of the first field of the first image sensor 14A and the second image sensor 14B are simultaneously magnetically recorded on the magnetic sheet 34 by the respective heads 32-1 and 32-3.

■After recording the feed, the system controller 4
8 switches the switches 26A and 26B to the b contact side using a switch changeover control signal 49 (FIG. 2 (6)).

At the same time, the recording gate signal 51 is applied to the recording amplifiers 3QA and 30B for one field period. This results in
The second of the first image sensor 14A and the second image sensor 14B
The output video signals of the fields are respectively Herad 32-2.
, 324 simultaneously perform magnetic recording on other tracks of the magnetic sheet 34.

Regarding the head drive during recording, the head 32-1
．． By driving the head 32-3 and the heads 32-2 and 32-4 alternately and simultaneously, interference due to cross talk between adjacent heads can be minimized and frames can be efficiently recorded.

In this way, the output video signal for one frame of the first image sensor 14A and the output video signal for one frame of the second image sensor 14B are recorded on the magnetic sheet 34. Third
The figure shows part of the recording track pattern. 54 is the first field signal of the image sensor 14A, and 55 is the second field signal.
Field signals 56 are the first field signals of the image sensor 14B, and 57 are the second field signals thereof. N.T.
In the case of the SC method, 262.5 H of signals are recorded on one track.

Next, the optical positional relationship between the image sensors 14A and 14B will be explained. FIG. 4 shows a front view of the imaging elements 14A and 14B viewed from the photographing lens 10 side.

As shown in FIG. 4, the image sensors 14A and 14B are arranged vertically offset from each other by 1/2 of one pixel in the vertical direction, and horizontally relative to the photographing lens IO. are placed in exactly the same position. And image sensor 1
On the imaging plane 4A, 14, as shown by diagonal lines in FIG.
A shielding mask 58 having a width of 1/2 pixel in the vertical direction and a pinch of 1 pixel in the vertical direction is placed thereon. By doing this, the 525-line frame image of the image sensor 14A and the image sensor 1
The 525 frame images of 4B are complementary to each other, and the total number of scanning lines is 525 x 2 =1.050.

FIG. 5 shows a block diagram of the configuration of the reproduction circuit of the magnetic sheet 34. 60 is a two-channel head, 62, 64 is a reproduction amplifier, 66 is a head selection switch, 68 is a reproduction equalizer, 70 is an FMul11 circuit, and 72 is a device. Emphasis circuit, 74 is output terminal for reproduced monochrome NTSC signal, 7
6 is an A/D converter, 78°80 is a frame memory, 8
2 is a synchronous separation circuit, 84 is a memory control circuit, and 86 is a D/
A converter, 88 is an output terminal for a high-definition video signal, and 90 is a system controller.

During reproduction, the magnetic sheet 34 is rotated at a predetermined rotation speed in the same manner as during recording, and the two heads of the two-channel head 60 correspond to adjacent tracks, for example, tracks 54 and 55 in FIG. are in contact with each other. The signal reproduced by head 60 is amplified by preamplifiers 62 and 64 and supplied to switch 66. The system controller 90 switches the switch 66 for each field in response to a PG pulse from the PG pin of the center core of the reproducing magnetic sheet. As a result, the equalizer 68 is supplied with a frame reproduction signal.

The FMifi circuit 70 performs FM demodulation on the output of the equalizer 68, and the de-emphasis circuit 72 performs de-emphasis processing on the demodulated signal.The output of the de-emphasis circuit 72 is N
This is a TSC signal, and if an NTSC monitor device is connected to the output terminal 74, an NTSC frame playback image will be played back and displayed on the monitor device.

Next, a case will be described in which a high-quality video signal output is obtained. The output of the de-emphasis circuit 72 is applied to the A/D converter 76 and the sync separation circuit 82. The synchronization separation circuit 82 separates the composite synchronization signal and applies it to the memory control circuit 84, and the memory control circuit 84 converts the sampling clock of the A/D conversion circuit 76 and the control signal of the frame memory 78 according to the composite synchronization signal. (Write clock, address signal, etc.)
occurs. A/D converter 76 performs A/D conversion using its sampling clock, and its output data is first stored in frame memory 78.

In this way, the image is photographed by the image sensor 14A, f,=
A signal for one frame is stored in frame memory 78.

After this, the system controller 90 controls the image sensor 14
In order to play back the frame image taken by B,
The hend 60 is moved to a position opposite the tracks 56, 57 in FIG. The reproduced frame signal obtained by this is transmitted to the system controller 90 and the memory control circuit 8.
4 is stored in frame memory 80.

After the storage in the frame memory 78, 80 is completed, the system controller 90 instructs the memory control circuit 84 to
The signal stored in the frame memory 78 is used as the first field, and the signal stored in the frame memory 80 is used as the second field, so that continuous output is performed at the high-definition rate. Data read from frame memory 78.80 is D/A
It is converted into an analog signal by a converter 86 and sent to an output terminal 8.
8.

The recording device shown in FIG. 1 and the playback device shown in FIG. 5 can realize recording and playback with a resolution of approximately 1,000 lines in the vertical direction, but they can also be used for normal 525 zero NTSC photography. That is, the half mirror 12 in FIG. 1 is placed in the normal mode (
525 zero NTSC), it is rotated in the direction of arrow A with its end B as the rotation axis, withdrawn from the subject optical path, and a subject image is formed only on the image sensor 14A. This allows frame recording similar to a normal NTSC monochrome still video camera. Furthermore, in this case, the loss due to the half mirror 12 is removed, so the S/N ratio is improved.

〔Effect of the invention〕

As can be easily understood from the above description, according to the present invention, a signal with twice the resolution in the vertical direction can be obtained using a conventional television type imaging means. Since a conventional television system imaging means is sufficient, a high-resolution camera can be realized at low cost, and a conventional television system video signal output can also be obtained, which is extremely practical.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram of an image recording device to which the present invention is applied, FIG. 2 is a timing chart thereof, FIG. 3 is a recording track pattern, and FIG. 4 is an image sensor 14A of FIG. 1.
, 14B, a front view showing the vertical positional relationship of the fifth
The figure is a block diagram of the configuration of the reproducing circuit. 10-4 darkest lens 12-half mirror 14A,
14B-i Most image element 26A, 26B-・Switch 3
2--Multi-channel head 34--Magnetic sheet 36-Center core 40-PG pin 42-PG detection coil 48--System controller Imaging point A diagram

Claims (1)

[Claims] a photographing optical system; a dividing means for dividing an optical image by the photographing optical system into two systems; first and second imaging means for photoelectrically converting the two optical images formed by the dividing means; It consists of a driving means for synchronously driving the imaging means,
The first imaging means and the second imaging means are arranged vertically shifted by 1/2 pixel on an optically equivalent surface, and on the imaging surfaces of both imaging devices, one pixel in the vertical direction is arranged. An imaging device characterized in that shielding masks extending in the horizontal direction with a width of about 1/2 pixel in the vertical direction are arranged at a pitch of 1/2 pixel.