SU1672520A1 - Device for displaying data on the cathode ray tube screen - Google Patents

Abstract

The invention relates to control devices and can be used in raster displays for displaying graphic information moving horizontally. The purpose of the invention is to improve the quality of the displayed information when the image is horizontally moved by increasing the smoothness of movement along the line of its constituent elements when the individual points and lines of the image are horizontally aligned relative to each other and relative to the other elements of the image at a distance of at least two samples. To do this, a selective video pulse extender, connected between video pulse generator 2 and video amplifier 4, is inserted into the device. Selective extender 3 consists of a trigger, a delay element, and an OR element with corresponding links between them. By using a selective expander 3, the illumination of single image elements consisting of one information discrete is performed with a brightness equal to that of several information discretes, as a result of which the number of information discretes in a line can be increased, which increases the smoothness of information movement along the line. 1 hp f-ly, 3 ill.

Description

The invention relates to control devices and may find application in raster displays to display information moving horizontally across the screen.

The purpose of the invention is to improve the quality of information displayed during horizontal movement of the image by increasing the smoothness of movement along the line of its constituent elements, when the individual points and the image line are horizontally one relative to the other and with respect to the other image elements at a distance of at least two samples.

In FIG. 1 shows a block diagram of a device; in FIG. 2 is a block diagram of a selective video pulse expander; in FIG. 3 voltage waveforms explaining the principle of operation of a selective video pulse expander.

The device contains a source of information 1, a generator of 2 video pulses, a selective expander 3 video pulses, a video amplifier 4, a scan unit 5 and a CRT

6. The inputs of the generator 2 video pulses are connected to the source 1 of information, and the outputs to the inputs of the block 5 scan and selective expander 3 video pulses.

The video pulse generator 2 contains a pulse generator 7, a frequency divider 8, an address counter 9, a memory unit 10, a multiplexer 11, a shift register 12. The output of the generator 7 is connected to the input C of the shift register 12, and through the divider 8 to the input of the shift register 12 and the counting counter input 9 addresses. The outputs of the counter 9 addresses are connected to the inputs of the block 5 scan. The outputs of the information source 1 are connected to the information inputs of the memory unit 10 of the multiplexer 11. Other outputs of the address counter 9 are connected to the address inputs of the multiplexer 11, and the outputs of the multiplexer 11 are connected to the address inputs of the memory unit 10, the outputs of which are connected to the information inputs of the shift register 12, the output of which connected to a selective expander 3 video pulses.

Selective expander 3 of the video pulses contains a trigger 13, a delay element 14 and an OR element 15. The output of the selective expander 3 of video pulses is the input mouth, 1 (input C) of the trigger 13 and is connected to the first input of the OR element 15. The output of the trigger 13 through the delay element 14 is connected to the second input of the OR element 15 and the input of the mouth O '(input R) of the trigger 13.

The video pulse generator 2 is intended for storing information, forming a sequence of video pulses, horizontal and frame sync pulses arriving at block 5. The video amplifier 4 and block 5 are generally accepted and explanation of their operation is not required. The source 1 of information may be a computer interface, the features of which are determined by the type of computer.

The information source 1 provides the information array to the memory unit 10 of the video pulse generator 2, which is stored in accordance with the addresses specified from the information source 1 through the address multiplexer 11 (Fig. 1). The memory unit 10 operates in the image regeneration mode and the issuance of information in it is necessary only when changing the image. Each bit of information in block 10 corresponds to a point on the screen of the CRT 6.

From the outputs of the memory unit 10, information is transmitted to the shift register 12, where it is converted into a serial code, which is a video pulse.

The pace of operation of the device is set by the generator 7. The pulses from its output shift information in the shift register 12. The conversion factor of the divider 8 is determined by the number of bits of the shift register 12. The signals from the output of the divider 8 switch the counter 9 of the address and transfer information from block 10 to the shift register 12 in accordance with the address coming from the address counter 9 through the multiplexer 11 to block 10. Thus, a bit code is sequentially read from block 10, which is continuously converted into a sequence videopulses spine.

In the process of working with the counter 9 addresses in block 5 scan receive line and frame clock. With each frame clock, the address counter 9 is reset and starts counting from the start address (this circuit is not shown in Fig. 1).

From the output of the shift register 12, the video pulses are fed to a selective expander 3 of video pulses (Fig. 2). On the leading edge of these pulses, the trigger 13 is set to 1, and after a time determined by the amount of delay on the delay element 14, it is set to 0. The output signal is generated by adding the input video pulse and the signal from the output of the delay element 14. In the oscillograms of FIG. Figure 3 shows the signals, respectively, at the input C of trigger 13. at its output, at the output of the delay element 14, and at the output of the OR element 15. It is seen that only short video pulses expand. designed to illuminate free-standing points.

From the output of the selective expander 3 video pulses, the signals are fed to the video amplifier 4 and then to the CRT modulator 6. where they modulate the brightness.

In practical implementation of the selective expander 3 of the video pulses, the delay element 14 is conveniently implemented in the form of a series-connected integrating chain and Schmitt trigger, which provide sufficient stability when the supply voltage changes. The degree of increase in discreteness along the line mainly depends on the CRT parameters, is selected experimentally in each particular case, and can reach 30%. At large values of increasing the resolution, a significant increase in the duration of video pulses is necessary, which will lead to the loss of information by reducing the pause after each individual point.

Thus, through the use of a selective expander of 3 video pulses, illumination of single image elements consisting of one information discrete is carried out with a brightness equal to the brightness of elements consisting of several information discrete, as a result of which the number of information discrete in a row can be increased by reducing the duration of the discrete , which will increase the smoothness of moving information along the line.

Claims (2)

Claim 1. A device for displaying information on the screen of a cathode ray tube (CRT), comprising an information source whose outputs are connected to the information inputs of a video pulse generator, the first and second outputs of which are connected to inputs of a scan unit, the outputs of which are connected to a deflector 10 with a CRT system, the modulator of which is connected to the output of the video amplifier, characterized in that, in order to improve the quality of the displayed information when moving the image 15 horizontally by increasing the smoothness of movement along the line of its constituent elements, when individual points and lines of the image are located horizontally relative to each other and with respect to the rest of the image elements at a distance of at least two samples, a selective video pulse expander is introduced into the device, the input of which is connected to the third at the outlet of the generator video pulses, and the output - to the input of the video amplifier 25. 2. The device pop. 1, the fact is that the selective video pulse expander contains a trigger whose output is connected to the input of the delay element, 30 the output of which is connected to the first input of the OR element and to the input of the trigger setting 0, the second input of the OR element is connected to the installation input 1 trigger, which is the input of the expander, the output of which is the output of the OR element. figure 2 1 — G input ~ C 13. Exit 13 Output / 4 ΓΊ. Output 15