SU1345248A1 - Device for reproducing information from optical medium - Google Patents

Abstract

The invention relates to computing. The purpose of the invention is to improve the reliability of information reproduction and simplify the device. On the fronts of the signal generated at the output of the comparator 3, the states of trigger 5 with the counting input change. The generator 6 generates a synchronous series, connected to the fronts of the signal at the output of the trigger 5 with a counting input. At the outputs of the D-flip-flop 7, paraphase signals are formed, which are the result of a census of the generated signal on the fronts of the sync serials. (The outputs of the formers 8 and 9 generate pulses, the beginning of the formation of which coincides with the fronts of the pulses in the signals at the outputs of the D-flip-flop 7. At the output of the OR 10 element, a signal of a logical addition of pulses is formed. The device has the ability to correctly separate data containing as symmetrical as well as single phase distortions. 3 ill. § W СА: 4 СД у 1 00

Description

one

The invention relates to computing technology, in particular, to a technique for reproducing information by optical means, and can be used as part of an optoelectronic storage device.

The purpose of the invention is to increase the reliability of reproduction of information and simplify the device.

Fig, 1 shows a diagram of the device; 2, time diagrams of his work; on fig.Z - the same.

The device (FIG. 1) contains a photodetector 1, an amplifier 2, a comparator 3, a source of reference voltage 4, a trigger 5 with a counting input, a generator 6, a B-trigger 7, drivers 8 and 9, an OR 10 element, an output bus

Fig. 2g. The forward and inverse outputs of the D-flip-flop 7 generate signals.

. (FIG. 2, g, g) resulting from the rewriting of the reproduction signal (FIG. 2d) to the output of the D-flip-flop 7, as shown in FIG. the fronts of sync pulse series (fig, 2e), and these sync series

10 is also supplied to the clock pulse bus 12,

At the outputs of the formers 8 and 9, on the fronts of the pulses (FIG. 2z, i) on the forward and inverse outputs B-trig

15 hera 7, signals are generated (fig, 2i, k), duration t, the output of the element OR 10 produces a signal (fig, 2n), which is the result of the logical addition of the signal information 11 and the sync pulse bus (fig , k) generated by the renonization 12, at the outputs of the formers 8 and 9. Thus, an output signal (FIG, 2L), represented in 25 passive form (1 input information corresponds to the playback time of a single level, low level), followed by a synchronization series (FIG. 2e) ..

Fig. 3 shows time diagrams of the device operation with a symmetric (& D.) and asymmetrical (2 / d, L) change in the duration of the playback signal (Fig, Sv) during the transfer of digital information (Fig. For) video record traces (FIG 3b),

The device works as follows.

The digital information (Fig. 2a) is transferred to a storage medium (not shown) in the form of recording tracks. (Fig. 2b) are distorted in length (the length of recording tracks has increased, and the intervals between them have decreased). The luminous flux modulated by the information recorded with distortions is converted by the photoreceiver 1 into electrical pulses amplified in amplitude by amplifier 2 (Fig 2b). The reproduced signal (Fig 2c) contains both symmetrical (L) and non-symmetrical ( 2L,) phase distortion. On the comparator 3, the amplitude comparison of the reproduced signal with the level of the reference voltage U, (FIG. 2c) takes place. At moments of equality at the output of the comparator 3, the fronts and decays of the reproduction signal (FIG. 2d) are formed, the position of which corresponds to the moment transition of reproducing radiation through the boundary of recording tracks. The signal (FIG. 2d) at the output of Trigger 5 varies along the fronts of the pulses (FIG. 2g) generated by the comparator 3. According to the signal (FIG. 2d) at the output of the trigger 5, the generator 6 generates a sync series (FIG. 2e) Algorithm of the device. . In this case, the case is analogous to the interrupt, t, e, on the signal fronts (Fig, 3g) formed at the output of the comparator 3, the states of the trigger 5 with the counting input (Fig. Rear), Generator 45 tor 6 change generates sync series

(FIG. ZE), tied to the signal fronts (FIG., RE) at the output of the trigger 5 with a counting input. At the outputs of the D-flip-flop 7, paraphase signals are formed (fig, zh, h) resulting from the census of the forms of a single signal (fig, zg) on the fronts of the sync pulse series (fig, z), at the outputs of the shape; drivers 8 and 9 are generated by pulse 50

(FIG. Ze), tied to the fronts of the signal (FIG. A) at the output of the trigger 5 with the counting input. At the outputs of the D-flip-flop 7, paraphase signals are formed (fig, Zj, h), which is the result of a census of the form of a single signal (fig, Zg) on the fronts of the sync series pulses (fig, Ze). changes in the phase of the fronts and decays of the signal (fig, 2d), 5d sy (fig, zi, k) with duration T, and consequently 5 and the signal fronts the formation of which coincides

playbacks (FIG. 2g), Spurs of i.- pulses in a sync series (FIG. 2e) coincide in time with the middle phase of the edges of the pulses in the signals (FIG. ZH, 3) at the outputs of the D-flip-flop 7 At the output of the element OR 10 forms 452482

Fig. 2g. The forward and inverse outputs of the D-flip-flop 7 generate signals.

. (FIG. 2, g, g) resulting from the rewriting of the reproduction signal (FIG. 2d) to the output of the D-flip-flop 7, as shown in FIG. the fronts of sync pulse series (fig, 2e), and these sync series

10 is also supplied to the clock pulse bus 12,

At the outputs of the formers 8 and 9, on the fronts of the pulses (FIG. 2z, i) on the forward and inverse outputs B-trig

15 hera 7, signals are generated (fig, 2i, k), duration t, the output of the element OR 10 produces a signal (fig, 2n), which is a re

The algorithm of the device operation ... in this case is similar to interrupting, t, e, on the signal fronts (Fig, Zg) formed at the output of the comparator 3, the state of trigger 5 changes with the counting input (Fig. Rear), General-- torus 6 produces sync series

(FIG. ZE), tied to the signal fronts (FIG., RE) at the output of the trigger 5 with a counting input. At the outputs of the D-flip-flop 7, paraphase signals are formed (fig, zh, h) resulting from the census of the forms of a single signal (fig, zg) on the fronts of the sync pulse series (fig, z), at the outputs of the shape; drivers 8 and 9 are generated

sy (fig, zi, k) with duration T, the beginning of the formation of which coincides

with the fronts of the pulses in the signals (fig, zh, h) at the outputs of the D-flip-flop 7, sigisgp (fig. 3l) of the logical addition of pulses (fig. 3, k) is formed at the output of the element OR 10.

The device has the ability to properly separate data, containing both symmetric and single phase distortions, which approximately 1.5-2 times increases the accuracy of information reproduction.

Claims (1)

Invention Formula A device for reproducing information from an optical medium, containing a series-connected | photodetector, amplifier ,, comparator, (trigger and generator, as well as source45248 4 Nickname of the reference voltage, D-trigger and output information bus, characterized in that, in order to increase the reliability of information reproduction, two shapers, the OR element and the synchronization pulse bus, are connected to the output of the reference voltage source 10 with the second input of the comparator, the output of which is connected to the D-input of the D-flip-flop, whose C-input is connected to the output of the generator, the outputs of the D-flip-flop through the drivers and the OR element 15 are connected to the output information bus, and the generator output is connected to the clock pulse bus. dzie.2