SU1317397A1 - Servo system for reproducing photorecord - Google Patents

Abstract

The invention relates to follow-up general purpose systems; designed to track the coordinates and reproduce the useful signal recorded on the photocarrier in a compact form by an order of magnitude and two orders of magnitude greater than the compactness of the magnetic recording. The purpose of the invention is to reduce the dynamic errors of reproducible photo recording information in a wide range of playback speeds. For this, a digital comparator, two single vibrators, a counter, an RS flip-flop, an OR element, an AND-OR element, a dynamic error corrector, a second comparator, a quantizing generator, and an I. element are introduced into the system. In addition, the converter contains a divider and n scaling channels, each of which contains a comparator connected to the first input of the NAND element, the second input connected to the I input of the second trigger and the output of the third trigger, C input combined with the output of the comparator, C input of the second trigger connected to the output element ENT is NOT, and the R-inputs of both triggers are connected channel by channel. The goal is achieved through digital correction. at different playback speeds. In addition, the formation of the strobe pulses of the extreme values of the synchronized viral photoconversion signal provides the averaging of the circumferential step of the raster path of the sensor-limb. 1 hp ff, 4 ill. c (L 00 SAE QD

Description

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The invention relates to general purpose tracking systems for tracking the coordinates and reproducing a useful signal recorded on a photo carrier in a compact form, in order and two orders of magnitude greater than the magnetic recording size.

The purpose of the invention is to reduce the dynamic error of the photo recording information reproduced by the system.

Figure 1 shows the structural diagram of the proposed device; Figures 2 and 3 are diagrams of a signal generated by a position sensor at different playback speeds; Fig. 4 shows a fragment of a position sensor (the raster element — a window and a flap — is in an intermediate position).

The following system for reproducing photo recordings (Fig.) Contains a setting device 1, an adder 2, a speed controller 3 for the executive engine 4, an adjustment object 5, a position sensor 6, a multichannel converter 7, a differentiator 8, a digital comparator 9, the first and second one-shot and 10 11, counter 12, RS flip-flop 13, element OR 14, element AND-OR 15, dynamic error corrector 16, second comparator 17, quantization generator 18 and AND element 19. Converter 7 contains a divider 20 and n scaling channels 21 each of which contains a comparator 22, lement AND-NO element 23, and second and third flip-flops 24 and 25.

 The raster elements of the position sensor 6, which contain a window 26 and a shutter 27 (figure 4) on the dials, modulate the backlight luminous flux, determine the coordinate position of the photo-recording signal, and the pulses (figure 2 and 3) are carriers of information on the number of circumferential steps from the starting position before the end of playback. Binding to the extremes of the modulated signal provides averaging of the circumferential pitch and reduces errors from the difference in width P of the grid window (Fig. 4).

Scaling channel 21 21 and divider 20 (FIG. 1) perform vertical scaling in the region of extreme values of photoconversion pulses x (t) (Figures 2 and 3) ensuring fixation of the extrema, and in counter 12 at the C1 input performed 73972

Records the number of vertical scale quantizations of the extremum region (Figures 2 and 3).

The setting device 1 is designed to set the speed of movement of the photo-recording medium, and in the counter 12, the C2 input records the number of temporal (horizontal) quantizations (Figures 2 and 3) by means of a stable oscillator 18 and an AND 19 element in the area bounded by the output signals triggered and non-triggered comparators 22 of each scaling channel 21.

15 Thus, in the counter 12, information is accumulated on two components: the playback speeds and quantizations in the extremum region of the function x (t) of the pulsed phototransformation.

When playing at different speeds, the frequency of the pulses of the signal x (t) is different and this determines the individual errors and the S formation of the extremum (Fig. 2 and SG. Since, for example, the comparator 22 is triggered in the extremum and returned to the original state

30 that forms the strobe impulse of the extremum, its hysteresis (f determines d is the parameter of the slope of the function x (t) and the errors different at different speeds. At a lower pulse frequency x (t), the function stretches along the time scale (FIG. H) and

To provide compensation for dynamic errors in the corrector. 16 introduces a numerical display of the error corresponding to a given speed of movement of the photo-recording medium. At adder 2, the said number is summed with the number of the reference velocity

 2-p P + P.

This sum is compared on the digital comparator 9 with the number that is recorded in the counter 12, and at the moment

50 gating this comparator on its outgoing outputs generates a mismatch signal acting on the controller 3 of the engine speed 4. This determines the three-position adjustment in each circumferential step of the sensor 1 limb raster. Since the raster lattice of the limb in the photo recording-playback system is selected with a number of transparent portions for 2 (in absolute values the window width is about 20 microns), then, the regulating effect of the error signal at the input of the speed controller 3 has a relatively large spectrum battening density. Therefore, when using known speed controllers with a stepper drive, high coordinate reproduction accuracy can be achieved with small oscillations.

The device works as follows.

Let playback speeds be

V.

V.

2 As a result of the modulation of the light flux of the backlight by the position sensor 6, a pulse signal x (t) is generated, which is fed to the first input of the converter 7. On the oscilloscope screen you can observe the difference in the shape of the pulses (Figures 2 and 3) according to the condition

15 that causes 1 at the output of the element IS-HAN 23 and the triggering of the I-prepared (1) trigger 24. At the pair And inputs of the element 17, a match 1 occurs, the RS flip-flop 1 returns to its original state, stopping the clocking of the counter 12 through The CI input by the pulses of the differentiator 8 passing through the element OR 14. With the return considered

(1), the dynamic error of the so-25 RS-flip-flop 13 to its original state

a single vibrator 11 forms a short pulse of gating of the comparator 9, which compares the recorded in counter 12

same is different.

At the moment when the signal x (t) reaches the level of operation of the comparator 17 on the element I 19, it becomes possible to quantize the counter 12 on the C2-INPUT and after the zeroing with the one-vibrator 10, which forms a short pulse when the comparator 17 is triggered, the information (number) of the playback speed is recorded (figure 2 and 3). When the signal x (t) reaches the operation level of the comparator 22, the C2-INPUT condition of the counter 12 is violated, since a logical unit is formed at the inverse input of the AND 18 element.

In the period between the actuators of the comparators 17 and 22 (the latter generates an extremum signal), information is allowed to be recorded into the counter 12 when enabled at the R input, because when the single vibrator 10 RS triggers, the trigger is set to the R state,

a single vibrator 11 forms a short gating pulse of the comparator 9, which compares the recorded in the counter 12

30 information with information of the adder 2. At the corresponding output of the comparator 9, a mismatch signal is generated in the measurement clock period. A three-position adjustment of the speed of the engine 4 is carried out. If, however, in the corrector 16 a number is written that reflects the dynamic error of the playback speed (the number in the setpoint 1), then the dynamic error of the reproduction is canceled.

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Claims (2)

1. A tracking system for reproducing a phototape containing a setpoint connected to the first input. adder, speed controller, output connected to the input of the Q motor, are installed in the R-state, on the output shaft Also, the triggers 24 and 25 of channel 21 of which the scale object is installed. Further, with increasing levels the x (t) signal in series with the output connected via position sensor to the input of the multichannel converter, the first group Comparators 22 22 ' of the codes of the scaling connected to the inputs are connected. For example, when the comparator 22 is triggered (transition to state 1), trigger 25 triggers, because its R-state (1 on of the rentirator, characterized in that, in order to reduce the dynamic errors of the reproduced information system of the photo recording, ka 20 I-input) allows it to trigger once. At the first AND input of an AND-OR gate, 1 occurs, which is transmitted to the first g input element AND-NOT 23 and the I-input trigger 24, preparing it to operate when forming 1 on the C-input. The second input of element 23 is from the work of your comparator 22 (from fO of the growing function x (t)) is in state 1, and at its output is 0. When the levels of function x (t) decrease, the comparator 22 returns to the initial state with hysteresis d (Figures 2 and 3), 15 that causes 1 at the output of the element / NAND 23 and the triggering of the I-input (1) trigger 24 triggered. At the paired AND inputs of the element 17, a match 1 occurs, the RS flip-flop 13 returns to its original state, terminating the clocking of the counter 12 through the CI input by pulses of differentiator 8 passing through the element OR 14. With the return considered - 25 RS-flip-flop 13 to the initial state RS flip-flop 13 a single vibrator 11 forms a short gating pulse of the comparator 9, which compares the recorded in the counter 12 information with information of the adder 2. At the corresponding output of the comparator 9, a mismatch signal is generated in the clock period of the measurement. A three-stage regulation of the speed of the engine 4 is carried out. If the number 16 in the corrector 16 is written to reflect the dynamic error in the playback speed (the number in the setpoint 1), then the dynamic error in playback is retired. Invention Formula 1. A tracking system for reproducing a phototape containing a setpoint connected to the first input. vani connected via position sensor to the input of the multichannel converter, the first group the codes connected to the inputs of the differential of the rentirator, characterized in that, in order to reduce the dynamic errors of the reproduced information system of the photo recording, 513 A digital comparator, two one-shot, count meter, RS-trigger, OR element, AND-OR element, correct dynamic error, second comparator, quantizing generator, and AND element are introduced, and the AND-OR element is connected to the first RS-trigger input the second input connected to the reset input of the counter and through the first one-shot one to the output of the second comparator, the outputs of the differentiator are connected to the inputs of the OR element, the output of which is connected to the clock input of the counter, which is connected to the output of the counting output of the RS trigger, and the output The meter is connected to the first input of a digital comparator, the second input of which is connected to the output of the adder, the input gate of the digital comparator is connected via a second one-shot to the second output of the RS flip-flop, while the inputs of the AND-OR element are connected to the second group of multi-channel transducer, the second input of which connected to the output of the first one-shot, the dynamic error corrector is connected to the second input of the adder, the quantizing generator is connected to the first input of the element I, the output of which is connected to the second clocking input of the counter, a third output connected to the multichannel transducer pervrmu input of the second comparator, the second input of which is connected to the output of the sensor position output of the digital comparator is connected to a speed regulator .The inputs of a torus, the first group of multi-channel outputs preob76 The diverter is connected to the second group of inputs of the element I, the third input of which is connected to the output of the second comparator. 2. The system according to claim 1, wherein the multichannel converter contains a divider and n, according to the number of sampling levels of the output signal of the position sensor, scaling channels, each scaling channel containing a third comparator, an AND-NOT element, a second trigger and a third trigger connected by an output to the first input element AND-NOT and I-input of the second trigger, the output of the third comparator is connected to the first input of the element AND-NOT and the C-input of the third trigger, the output of the element AND-NOT connected to the C-input the second trigger, the third output of the trigger is connected to the I input of the same trigger, the first input of the third comparator is connected to the corresponding output of the divider, the combined second inputs of the third comparators of each scaling channel are connected to the first input of the converter, the second input of which is the combined inputs reset the second triggers of each scaling channel, the outputs of the third comparators of each scaling channel are the first group of outputs of the converter, the first codes of the second and third triggers of each analog scaling are the second group of outputs of the converter, the third output of which is the (n + 1) -d output of the divider. figl