JPS6210985A - Color image pickup device - Google Patents

Abstract

PURPOSE:To obtain a good horizontal resolution by arranging the longitudinal direction of the stripe of a color stripe film consisting of plural pairs in parallel with the scanning direction of an image pickup tube. CONSTITUTION:A signal obtained from an image pickup tube 1 on which a color stripe filter 1a is provided is AD-converted at an AD converter 3, and is supplied to field memories 4a and 4b. Writing and reading by every pair is repeated alternately corresponding to a control signal from a switching circuit 5, and as for the reading, data by every pair is read as the information of the first field F1 with the time base of an NTSC system and is DA-converted at a DA converter 6. The information of the second field F2 is read out with being shifted by 1/2 of each pair in the perpendicular direction of the information of the first out from the DA converter 6 is color-demodulated at a color demodulation circuit 7. Thereby, the good horizontal resolution can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a color imaging device, for example, in a single-tube color television camera, a color multiplexed signal is obtained from an image pickup tube provided with a color stripe filter, and color demodulation is performed. related to a device for

2. Prior Art Regarding the conventional single-tube color television camera, for example, the present applicant has disclosed Japanese Patent Application No. 54-28450 (Japanese Patent Publication No. 59-35).
550), [Color Chee Revision Signal Generator], J: urchin, for example, the stripe length direction of the color stripe filter consisting of repetitions of G (green), C (cyan), and W (transparent). A color multiplexed signal is obtained by scanning in a direction perpendicular to the color.

Problems to be Solved by the Invention The above-mentioned conventional method performs scanning in a direction perpendicular to the longitudinal direction of the stripe. Color multiplexing is performed using a high carrier wave, and the noise is in the high range.
Also, since the modulation degree of the image tube is as low as ^, as a result,
The signal-to-noise ratio is low, and the image pickup tube cannot faithfully reproduce the state of the color stripe, resulting in poor color reproducibility.

In addition, since this device scans in a direction perpendicular to the longitudinal direction of the stripes, a color-multiplexed signal is obtained in the scanning direction.As a result, the luminance signal band is limited by the color-multiplexed carrier wave, and the band There was a problem in that the area became narrow and good horizontal resolution could not be obtained.

The present invention achieves color multiplexing using relatively low carrier waves.
To provide a color decoy image device capable of obtaining a high signal-to-noise ratio of 1q, high Q/1 color reproducibility, wide luminance signal band, and good horizontal resolution. What is the purpose?

Means for Solving the Problems In FIG. 1, the color stripe live filter 1a is an optical color separation means, Ar, whose longitudinal direction is arranged parallel (substantially parallel) to the scanning direction of the image tube 1. ) converter 3, memory 4a, 4b
, the switching circuit 5, the DA converter 6, and the color demodulation circuit 7 shift the pitch in the direction perpendicular to the scanning direction of the image pickup tube 1 at least every other field, and remove the color multiplexed signals one set at a time in the direction perpendicular to the scanning direction. 3-3 are respective embodiments of means for demodulating;

Function A plurality of sets of color stripe filters 1a with a plurality of different filter strips 111 are arranged with the longitudinal direction of the stripes parallel (substantially parallel) to the scanning direction of the image pickup tube 1, and an AD converter 3, a switching circuit 5, Memory 4a.

4b, when the pitch in the direction perpendicular to the scanning direction of the image pickup tube 1 is slightly removed by the DA converter 6, 1) a color multiplexed signal is obtained in each direction perpendicular to the scanning direction by shifting every other field; Then, the color demodulation circuit 7 performs color toning.

Embodiment FIG. 1 is a block 1-1 ivy system diagram of an embodiment of the device of the present invention.
FIG. 2 is a diagram showing the relationship between the color spectrum 1 to the live filter used in the apparatus of the present invention and the scanning line. As shown in FIG. 2, the apparatus of the present invention is configured to scan in the longitudinal direction of the stripes of a color stripe filter 1a consisting of repeated G, C, and W filter strips. The number of lines A is the number that the color stripe filter 1a can reproduce as samples, for example, G,
The number is set to 6 for each pair of C and W. This number of sets is set to, for example, 240 sets (corresponding to one field in the NTSIC system). This is said to be compatible with the step energy method, and in the step energy method, it is only necessary to reproduce the fundamental wave component and the second harmonic component, but the number of scanning lines is a sampling constant. Oshikarajuki 11
If there are 4 or more pieces per address, it can be reproduced.

In Fig. 1, the color shown in Fig. 2 - live filter 1
The signal obtained from the image pickup tube 1 provided with the image pickup tube 1 is supplied via the preamplifier 2 to the AI') converter 3, where it is AD converted and stored in the field memory 4a.

4b, and is written therein or read out therefrom in accordance with a control signal from the switching circuit 5.

Here, G and C of the color stripe filter 1a.

The cycle of the W1 set is set to correspond to 1H in the NTSC system. First, the first field will be explained. In the IHth field of the first field, Ar) converter 3
The signal from is stored in the memory 4a at points a11 and 812 shown in the second diagram.
・a13・°°°・821・822・823・・・・a
31. a32. a33. ... are sequentially written in the direction (FIG. 3(A)). In the 2H, the signals of the first set S1 written in the memory 4a are at 9 corner points a11, 821, a31, a41, 851, a61, in the direction perpendicular to the writing direction.
a12・a22・a32・a52・a62・a13・a
23, a33, a43, a53, a63, and °°°, while the signals from the AD converter 3 are stored in the memory 4b at points 871, a72, a73'""a81'
a82'a83. ..., a91. a92. a93.
...Then, the signals of the second set S2 written in the memory 4b are written in the direction perpendicular to the writing direction, that is, the point 871・881・891・°°°・812・882・
892・°°°・a73. a83. a93. ..., while the third set of signals from the AD converter 3 is newly written to the memory 4a.

Thereafter, in this way, one set at a time is written to the memories 4a and 4b, and reading is repeated alternately, and in the end, one set at a time, that is, 111 minutes, is successively read out as the information of the first field F+ on the NTSCh time axis. , are supplied to the DA converter 6, where they are converted into DA.

The signal obtained by DA conversion is a signal in which each group is arranged on the simultaneous time axis as shown in FIG. 4, and is similar to a color multiplexed signal obtained by a general step energy method. In this case, if the above sampling theorem conditions are satisfied, the signal will be the same as the signal multiplied by the step energy method, and even if the sampling phase and its frequency change, the fundamental wave component signal and the second harmonic Wave component signals can be faithfully reproduced.

Next, the second field will be explained. In the 1H of the second field, the signal from the Ar) converter is transferred to the memory 4.
Point a, a, a,..., a51°a5 at a
2・ a53・°°°・ 861・ a62・ 863
・°゛°・ 871・a72・ a13・°°°・ a
81・a82・a83・°°°・a91・a92
．． a93. ..., are written sequentially in the direction. In the 2H, the signal written on the main line 4a is perpendicular to the writing direction, that is, at the point a41. a51. a61. a71゜a81・
a91/a42/a52/a62/a72/a82/8
92/843/a53/a63/873/a83/a9
While the signals from the AI') converter 3 are sequentially read out in the direction of 3.°゛°, the signals for the next six scanning lines are sequentially written into the memory 4b in the same direction as in the case of the 1H. .

By repeating such writing and reading,
The information in the second field F2 is vertically shifted from the information in the first field by 1/2 pitch of each set and read out on the time axis of the NTSC system, and is converted into I)A by the r)A converter 6. .

r) The signal taken out from the A converter 6 is supplied to a color demodulation circuit 7 having a similar configuration to a step energy type color demodulation circuit, where it is color demodulated and taken out from an output terminal 8.

In this way, in the device of the present invention, the color stripe filter 1a
Since we are scanning in the longitudinal direction of the stripes, G.

For the period of 1 set of C and W (corresponding to 11-1 in the NTSC system), the fundamental wave component is 15.75 kHz x 6 = 9
Color multiplexing is performed using a relatively low carrier wave of 4.5 kHz, which results in a higher signal-to-noise ratio than the conventional device N. Also, the image pickup tube can faithfully reproduce the state of color stripes, resulting in improved color reproduction. Improves sex.

Furthermore, since the device of the present invention scans in the longitudinal direction of the stripes, there is no color multiplexing in the horizontal direction, and as a result, the same resolution as black and white can be obtained, and the luminance signal band is limited by color multiplexed carrier waves. The bandwidth is wide (
q1 Good horizontal resolution can be obtained.

Note that the vertical deviation of the second field signal with respect to the first field is not limited to 1/2 pitch as in the above embodiment.

Note that when the scanning direction of the image pickup tube is vertical, the longitudinal direction of the stripes on the color stripe filter is also vertical, and the memories 4a and 4b are written in the vertical direction. All you have to do is read it out.

Effects of the Invention According to the device of the present invention, since the image pickup tube is scanned in the longitudinal direction of the stripes of the color stripe filter, color multiplexing is performed using a relatively low carrier wave. In addition, it is possible to obtain good color reproducibility, to obtain a wide luminance signal band, and to obtain good horizontal resolution. Therefore, the signal can be read out on the 1H time axis of the NTSC system, which eliminates the need for time axis conversion means and requires less memory space. Since the color multiplexed signal is obtained by shifting the pitch, the above pair is N T S C
If set to correspond to method 111, 11-1
It has features such as being able to increase vertical resolution within the range of .

[Brief explanation of drawings]

1 and 2 are respectively a block diagram of an embodiment of the device of the present invention and a schematic diagram of a color stripe filter used in the device of the present invention, and FIG. 3 is a diagram for explaining the state of inflow into the memory. FIG. 4 is an input signal waveform diagram of the color demodulation circuit in the apparatus of the present invention. 1... Image pickup tube, 1a... Color stripe filter, 3
...AD converter, 4a, 4b...memory, 5...
Switching circuit, 6...DA converter, 7... Color demodulation circuit,
8...Output terminal.

Claims (1)

[Claims] A color stripe filter consisting of a plurality of sets of different filter strips is arranged with the longitudinal direction of the stripes parallel (substantially parallel) to the scanning direction of the image pickup tube, and at least every other field in a direction perpendicular to the scanning direction. 1. A color imaging device characterized in that the color image pickup device is configured to obtain the color multiplexed signals one by one in a direction perpendicular to the scanning direction by shifting the pitch of the signals and perform color demodulation.