SU1454735A1 - Apparatus for raster synthesis of image photocopies - Google Patents

Abstract

The invention relates to devices for the raster synthesis of photocopies of images. This device improves image quality by eliminating electrical instability. This is accomplished by eliminating the amplification path of the analog signal, which is a video amplifier with direct connections, which is subject to significant temperature drift. The introduction of fixed amplitude generators ensures the stable formation of raster points and allows the lawsuit to whine the need to adjust the device when switching from one image to another. 2 Il. S (L with

Description

The invention relates to devices for the raster synthesis of photocopies of images.

The purpose of the invention is to improve the quality of images by eliminating the instability of electrical parameters.

FIG. 1 shows a block diagram of a device for raster synthesis of photocopies of images; in fig. 2 is a block diagram of a fixed amplitude generator.

The device (Fig. 1) contains optically coupled rasterizing electron-beam 10 tubes (CRT) 1 with deflecting systems 2, objectives 3, dichronic mirror 4, and a drum 5 for electrically driven photocopies. The device also contains generators of 6 fixed amplitudes, a synchro generator 7, a generator of 8 rectangular pulses, and a generator of 9 sawtooth pulses. At the same time, one of the outputs of the synchronous generator is connected to the inputs of the generators of rectangular and sawtooth pulses, the second output of the synchronizing generator is connected to the electric drive 5, the third output to the first inputs of the generators 6 of fixed amplitudes. The outputs of the square pulse generators are connected to the electrodes of the control systems of the CRT 1, and the output of the R29 sawing pulses are connected to the deflecting systems 2 of the CRT 1. The outputs of the generators 6 of fixed amplitudes are connected to the electrodes of the control systems of the CRT. 1, and a digital video signal is applied to the second inputs.

FIG. 2 shows a register 10 connected by wires II to a decoder 12, a node 13 of keys, a switch 14, a voltage divider 15, a voltage stabilizer 16, a voltage divider 17, and an adder 18.

The device works as follows.

The digital video signal coming from the communication channel is supplied to the generators 6 of fixed amplitudes, which, depending on

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ti | from the input number, to generate | output, at the output, different values of fixed amplitudes applied to the controller (which are CRT electrodes 1, i.e., at six-byte input signal, the generator generates 64 fixed values eg in the range of 0.05-30 V. At the same time, the distribution of amplitudes depending on the input signal is selected taking into account the non-linearity of the through-path light-to-light, which also eliminates such components from the electrical path as gradation correctors of synthesis representing soy non-linear functions Synchronous converters. Synchronizer 7 represents with Zoya the generator of sequences of sync pulses, which controls the operation of the mash gene for 8 rectangular pulses, the generator of 9 sawtooth pulses, and electric drive drum 5. Generated in duration and amplitude, the pulses from the generator output 8 rectangular pulses served on the modulating electrodes of the control systems of a CRT 1. The amplitude of the sludge / pulses for reliable locking of the rasterizing CRT 1 at the moment of pauses is 30 | B. For a synthesis lineage of 36 lines / cm, the pulse duration is 45 µs (the time Mjj during which the CRT is open), the tracking distance is 50 µs. From the output of the generator 9 sawtooth pulses to the oscillating systems 2 of the CRT, current pulses appear, providing strobing of the first spots on the surface of the drum 5 due to the synchronous deflection of the spot on the screen of the tube. For the same synthesis linearity, the current aflitude is 200 mA, the forward stroke duration is 45 µs, the reverse stroke; 5 µs

The fixed amplitude generator b (Fig. 2) works as follows, the paradisplay image output signal is fed to the reg. Page 10, clocked by the clock frequency of the sync generator 7. From the register output 10 p-2 bits go to the decoder 12 of the type "1 of N where N is the number of: outputs of the decimator 12. P 2-bit-1i image signal performs a 6cip of one of the N transistor keys of the node 13 connected to the outputs of the decoder 12. One of the selected N transistor keys of the node 13 is closed, and a voltage is set at its collector, l emoe starschimi two bits of the image signal fed to the switch 14, which depending on the incoming code selects the voltage applied to its analog input. These voltages are determined by the voltage divider 15 to which the initial voltage comes from the voltage regulator 16. The storage on the collector of the selected one of the N transistor switches of the node 13 op0

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It is also determined by the voltage divider 17, which supplies the voltage coming from the switch 14. Thus, depending on the input image signal, one of the transistor switches of the node 13 is selected, and the voltages on it also vary depending on the image input signal. The summation of the output voltage occurs in the adder 18.

Voltage dividers 15 and 17 can be assembled on resistors connected in series between the output of voltage regulator 16 (for voltage divider 15) and the output of switch 14 (for voltage divider 17) and the device case.

5The enhancement of photocopy quality is achieved by eliminating the amplification path of the analog signal, which is a video amplifier with direct connections, which is subject to considerable temperature drift. A slight deviation of the amplitude of the video signal from a given value leads to a change in the spot size on the tube screen and, consequently, the raster point on the photocopy. Changing the magnitude of the raster point causes traditional

5 distortion in black and white images and color distortion in color images. The introduction of a generator of fixed amplitudes, which ensures the stable formation of raster points, allows

In addition, Q eliminates the need to adjust the device for raster synthesis of photocopies of images when switching from one image to another, which, as a result, shortens the time for making photocopies.

5 The use of the invention improves image quality by eliminating electrical instability.

Claims (1)

Invention Formula 0 A device for raster synthesis of photocopies of images containing a developmental drum for photocopies mounted on the shaft of an electric drive connected by an input to the first output of a synchro-generator, 5 connected by a second output to the input of a generator of rectangular pulses, and an input of a generator of sawtooth pulses connected by an output to the inputs of deflection systems of rasterizing cathode-ray tubes connected by the first inputs of their control systems to the output of a generator of rectangular pulses, a dichroic mirror, optically connected to the working area on the surface of the developing photocopy drum and through the lenses optically connected to the surface of the screens of the rasterizing cathode ray tubes, In order to improve the quality of images by eliminating the instability of electrical parameters, it is equipped with generators of fixed amplitudes connected by inputs to an additional output of a synchronous generator, while the second inputs of control systems of rasterizing cathode-ray tubes are associated with the outputs of corresponding generators of fixed amplitudes. Fy Phys .2