SU467496A1 - Device for eliminating oscillations during optical-mechanical scanning - Google Patents

Description

The invention relates to the field of facsimile technology. A device for eliminating oscillations in an optical-mechanical scan is known, comprising a driver, a sampler, a selector, memory devices, a counter, a clock frequency generator, keys, an inverter, an optical sensor. Fax machines of such a device have insufficient speed. In the described device, in order to increase the speed of operation of fax machines, two- and three-position keys are introduced. The drawing shows a block diagram of the described device. The device contains form 1, a sampler 2, a two-position key 3, a selector 4 stitching pulses, three-position keys 5 and 6, a two-position key 7, a memory of 8 odd lines, a memory of 9 even lines, two-position keys 10 and AND, a circuit 12 "OR , three-position key 13, phase inverter 14, coordinate optical sensor 15, key 16, counter 17 synchronization pulses, counter 18 raster-line elements, clock generator 19. The video signal is input to the device from a photoelectric converter of an optomechanical analyzing device (not shown in the drawing). The video signal containing the flashing pulses simultaneously arrives at shaper 1 and selector 4, is converted by the shaper into a square wave signal and of a certain amplitude, and then goes to the sampler 2. At the same time, the sampler passes through the phase inverter 14 a pulse sequence (strobe pulses) from the coordinate optical sensor 15. With the help of sensor 15, the analyzed line is conditionally divided into identical elementary sections — raster elements, the length of which does not exceed the width th element. The coordinate sensor can be, for example, made as a set of a disk containing uniformly applied radial slits ("windows) along the edge, the number of which is equal to the number of rasters in the output shaft of the gearbox that drives the spreading elements, as well as a photo sensor consisting of a light source and a photodetector. The disc strokes modulate the light flux of the light source, the photodetector converts the modulated light flux into a sequence of electric rectangular pulses, following in time according to the law determined by law

rotation of the disk, which is rigidly connected with the output shaft of the drive mechanism (gearbox) of the spreading device. Strobe pulses are formed from the leading edges of these pulses. Thus, the strobe pulse law is a function of the sweep of a sweep device. The pulse sequence at the output of sampler 2 is phase-modulated, which is determined by the sweeps of the sweep device. However, due to the synchronism of the rotation of the disk of the coordinate sensor and the movement of the sweep elements, the effect is achieved of a uniform (with respect to the ordinates of the raster elements) reading information from the analyzed line, regardless of the intensity of oscillations.

The discretized information signal arrives at the two-position key 3, which closes the starting pulse generated by the selector 4 along the rear edge of the pulse “SYN1. Keys 5 and 6 are in the initial state in the neutral (middle) position. With the arrival of the first start pulse, they switch to the up position. As a result, the Discretized information signal, having passed the key 5, falls on the first cell of the storage device of 8 odd lines. According to the first informational impulse, information is recorded in this cell.

The storage device operates on the basis of a shift register. The information in the register is driven by clock pulses from the phase inverter 14, formed on the falling edges of the square pulses produced by the coordinate sensor 15. In this case, the clock pulses follow the same law as strobes, which determine the sequence of information pulses, but are shifted by Relation to the last. This ensures the normal progress of the process of promoting information on the register. The number of cells is determined by the number of raster elements in the analyzed image line.

After the string has been written, a stop pulse generated in the selector 4 on the leading edge of the flush pulse, the keys 5 and 6 are moved to the neutral position and writing to the register is stopped. Information is read from the register by pulses produced by a highly stable clock frequency generator 19. The stability of the generator has the same requirements as that of the master generator that drives the sweep device.

The first starting impulse from the selector 4 closes the key 7, while the counter 17 starts working. The key 7 remains in the closed position until the end of work, the incoming starting impulses only confirm its closed position. Counter capacity 17

equal to the number of raster elements in the full line (in the useful line, along with the "stitching").

In the initial position, the key 13 is in the neutral (middle) position. After the counter 17 is filled with the output pulse, the keys 10, 11, 13 and 16 are moved to the upper position. The read pulses from the generator 19 through the closed keys 7 and 13 arrive at the memory of its device 8 odd lines, and the information about the content of the first line comes through the closed key 10 and the OR 12 circuit to the modulator of the facsimile transmitter or the computer input (not shown ). The raster-element counter 18 is filled through the closed key 16. The capacity of the counter 18 is equal to the number of raster-elements in the useful image line. The process of reading information from the memory device stops after filling the counter 17. In this case, the pulse 13 at the output of the counter 17, the key 13 is set to the neutral position, and the key 16 - open. The second starting impulse from the selector 4

switches the keys 5 and 6 to the lower position, after which the second line of the image begins to be written into the memory device of 9 even lines. This process is similar to writing information to the odd-line memory. Recording tue; oops line and

read first line information from

odd-line memory

happens almost simultaneously.

When the second line has finished recording the second, stop pulse from the selector 4, keys 5 and 6 are moved to the neutral position. After the secondary filling, the counter 18 moves the key 13 to the lower position, and the key 16 to the upper position. Starting from this moment, information is read from the storage device of 9 even lines. It is similar to reading information from odd lines. This alternates between writing and reading.

odd and even lines of the recorded image.

Since the reading is performed using a clock frequency of high stability, and when writing due to the principle

the coordinate sensor, each raster element is located exactly in the corresponding memory cell, in the output signal there are no oscillations.

Subject invention

A device for eliminating oscillations in an optical-mechanical scan, comprising a driver, sampler, electronic key, stitching pulse selector, even and odd line memory, OR circuit, phase inverter, optical coordinate sensor, synchronization pulse counter, line raster-element counter, clock generator, characterized in that, in order to increase soon

facsimile machines, two- and three-position keys are inserted into it, and the input of a two-position key connected to a follower; 1o with a three-position key, the control inputs of which are sent from the pulse selector “stitching”, the second three-position key between the phase inverter output connected to a coordinate optical sensor and memory inputs whose control inputs are controlled by a pulse counter via the third three-position key; synchronization and a raster line counter, are connected to the clock pulse counter input and through an additional two-position key, controlled by a signal from the cross-link imiums selector switch, to the clock generator output, and between the OR outputs of the two positions; 1st

the keys whose control inputs by,.; are connected to the output of the clock pulse counter.