SU1536457A1 - Device for reproduction of colour image - Google Patents

Abstract

The invention relates to television. The purpose of the invention is to improve the image quality. The color image reproducing apparatus includes an index color cathode ray tube 1, an index signal detector 2, an index signal delay unit 3, a control pulse shaper 4, a backlight pulse shaper 5, a backlight pulse switch 6, a chrominance switch 7, and buffer memories 8. The goal is achieved by increasing the purity of the colors. 2 Il.

Description

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The invention relates to color television and can be used in color image reproducing devices on index color cathode ray tubes.

The purpose of the invention is to improve the image quality by improving the purity of the colors.

Fig. 1 shows a structural electrical circuit of a color image reproducing device; Fig. 2 shows diagrams of electrical signals at various points of the device.

The color image reproducing device comprises (FIG. 1) an index color cathode ray tube 1, an index signal detector 2, an index signal delay unit 3 and a control pulse driver 4, a backlight pulse driver 5, a backlight pulse switch 6, and the switch 7 of signals chromaticity and n buffer blocks of 8 memory. The input of the illuminator pulse generator 5 is the input of the synchronization pulses. The output of the illumination pulse generator 5 is connected to the second input of the control pulse generator 4 with the control input of the switch 6 of the illumination pulse and with the gate inputs of the first ... nth buffer memory blocks 8. 1 ... T the control inputs of the first ... nth switch | 7 of the chromaticity signals are connected respectively to the 1.s. Outputs of the driver 4 control pulses. 1 ... T outputs of the driver 4 control pulses are connected respectively to 1 ... T clock inputs of the first. .. of the nth buffer block of 8 memory. 1 .., t, the information inputs of the first ... nth switch 7 of the chromaticity signals are connected, respectively, with 1 ... P outputs, respectively, of the first ... nth buffer memory blocks 8. The output of the first switch 7 of the chrominance signals is connected to the first input of the switch 6 of the illumination pulse. The second input of the switch 6 of the illumination pulse is the input of the voltage of the illumination pulse. The output of the switch 6 of the illumination pulse and the outputs of the second ... nth switch 7 of the chromaticity signals are connected respectively to 1 ... P inputs of the index color cathode ray tube 1. The inputs of the first .c of the nth buffer block

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The 8 memories are inputs of chrominance signals.

The color image reproducing apparatus operates as follows.

When the illumination pulse of the first synchronization pulse (Fig. 2a) arrives at the input of the imaging unit 5, a light pulse (Fig. 2b) is formed with a forward stroke duration equal to the length of the scanning line of the electron beam on the screen of the index color cathode ray tube 1. the illumination is fed to the second input of the driver 4 of the control pulses, to the gate inputs of the first ... nth buffer memory blocks 8 and to the control input of the switch 6 of the illumination. As a result, the switch 6 of the illumination pulse supplies to the first input of the index color cathode ray tube 1 the voltage of the illumination pulse (Fig. 2b). The light pulse prohibits the output of chroma signals from the buffer memory blocks 8 and the control pulses from the driver 4. Since there is no signal at all inputs of the index color cathode ray tube 1, except for the first one, TC scans the first electron beam across the screen at the output of the index signal detector 2 and creates an index signal (Fig. 2b), which is delayed in block 3 of the index signal by time one line (figg). When the illumination pulse of the second synchronization pulse arrives at the input of the imaging unit 5, the illumination pulse terminates at its output. At this moment, at the first input of the driver 4, the control pulses begin to arrive from block 3

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holding the index signal, the index signal, and on the 1 ... T output of the driver 4 control pulses, the control pulses corresponding to the index signal (fig. 2e) are generated, controlling the switches 7 of the chromaticity signals. The chroma signals coming from the buffer blocks 8 of the memory to the information inputs of the switches 7 of the chroma signals are switched at the corresponding moments of time to match the electron beams of the index color cathode ray tube 1 defined by

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index signal received in the previous sweep period of the first electron beam. The chroma signals to the first electron beam are output from the first switch 7 of the chroma signals through the switch 6 of the backlight pulses (Figure 2e). To synchronize the output of chroma elements from the buffer memory blocks 8 with the frequency of the index signal, control pulses are sent to their synchronization inputs from the outputs of the driver 4. This avoids loss of information when playing video signals of short duration, for example, alphanumeric information.

Claims (1)

Invention Formula And 3 A color image reproducing device comprising an index color cathode ray tube, a first color signal switch and serially connected index signal detector, an index signal delay block and a driver for controlling pulses, 1 ... t whose outputs are connected respectively to 1 ... t control the inputs of the first chrominance signal switch, where m is the number of primary colors of the index color cathode ray tube, characterized in that, in order to improve the image quality by chsheni color purity are introduced illumination pulse shaper, a pulse switch 0 7 " illumination, the second ... nth color signal switches, where n is the number of electron beams in the index color cathode ray tube, and the first ... nth buffer memory blocks, with the input of the backlight pulse generator being the input of synchronization pulses and the output is connected to the second input of the control pulse generator, with the control input of the backlight pulse switch and with the building inputs of the first ... nth buffer memory blocks, 1 ... t control - 5 second inputs of the second .. The n-th commutators of the chromaticity signals are connected respectively. A c 1 ... ha outputs of the control pulse generator, 1 ... t information inputs of the first ... nth color signal switchboard are connected respectively to 1 ... m outputs, respectively, of the first one. The nth buffer memory blocks, the output of the first chrominance switch are connected to the first input of the backlight pulse switch, the second input of which is the input of the backlight pulse voltage, the output of the backlight pulse switch, and the outputs of the second ... nth switch The chromaticity signals are connected respectively with 1 ... P inputs of the index color cathode ray tube, 1 ... T outputs of the control pulse shaper are connected respectively with 1 ... T synchronization inputs of the first, ... nth buffer memory blocks. 0 five 0 five (rig. g