SU1499403A1 - Holographic storage - Google Patents

Abstract

The invention is intended for use in optical information processing systems. The aim of the invention is to increase the reliability of the device by increasing the reliability of reading information in the holographic storage device by increasing the width of the radiation spectrum and the size of the radiating region, resulting in deterioration of the quality of the reconstructed image. To control the quality of the restored image, elements AND 34,36,40,41, RS = triggers 35,38,42, counter 37 with a predetermined recalculation module, element OR 43, threshold element 33 and block 39 of the output from stro radiator ". This allows analyzing the width of the radiation line of the radiation source 1, taking into account the increase in the image elements depending on the size of the radiation area, changing the algorithm of the device operation, signaling unacceptable deterioration of the image quality and the need to replace the radiation source. 2 Il.

Description

Output

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with

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The invention relates to an optoelectronic technique and can be used in optical information processing systems, in fiber-optic communication lines, in optical storage devices, mainly in holographic storage devices.

The purpose of the invention is to increase the reliability of the device: - by increasing the reliability of information readout in the holographic storage device.

FIG. 1 shows a photosensitive area of a photodetector unit with an identification mark projected on it, a fragment in FIG. 2, a functional block diagram of a holographic memory device.

With a constant width of the radiation spectrum of the radiation source and the size of the radiation region, the size 1 (FIG. 1) of the identification mark corresponds to the elements of the photoreceiver unit. The values of 1, hence k, are determined by the information recording conditions and the type of Semiconductor laser used. With an increase in the width of the radiation spectrum or an increase in the size of the radiation region, the size 1 increases to L (dotted line), which corresponds to the i elements of the photosensitive region of the photodetector unit. When a certain value P is reached, the increase in size reaches such a value that the elements of the information image are superimposed on each other, i.e. the information is distorted.

The holographic memory device (Fig. 2) consists of a scanning radiator 1, optically coupled through sequentially located collimator 2 and the carrier 3 of holographic information with a matrix photo-receiving unit 4, the pumping unit 5, the output of which is connected to the input of the scanning radiator 1, unit 6 a control consisting of a start node 7, an RS flip-flop 8, a standby generator 9, and a distributor 10 sync pulses. The input of the start-up unit 7 is the third control input of the control block b, the second one. The input of the start-up unit 7 is the first control input of the control unit 6, the output of the start-up unit 7 is the first output of the control unit 6 and

connected to the S-input of the RS-flip-flop 8 and the control second input of the distributor 10 clock pulses, the direct output of the RS-flip-flop 8 is the fourth output of the control unit 6, the inverse output of the RS-flip-flop 8 is connected to the input of the waiting generator 9, the output of which is connected to the first input of the distributor 10 clock pulses, the first and second outputs of which are the second and third outputs of the control unit 6, respectively.

In addition, the device consists of an information fragment allocation unit 11, an analog-digital converter 12, an output driver 13, a signal containing a series-connected adder 14, a threshold element 15 and an AND element 16, the second input of which is the control input of the output generator 13 The signal, the output of the element AND 16 is the output of the device, the former 17 phase voltage generator containing the first 18 and second 19 pulse generators, two elements AND 20 and 21 element OR 22, counters 23-25, with the output of the generator 18 and pulses is the first output of the phase voltage generator 17 and connected to the first inputs of the elements 20 and 21, the second inputs of which are the third and second inputs of setting the modes of the phase voltage generator 17, respectively, the output of the element 20 and 20 are connected to the counting input of the counter 23 and is the second output of the phase voltage generator 17, the output of the AND 21 element is connected to the counting, the input of the counter 24, the outputs of the counters 23 and 24 are connected respectively to the first and second inputs of the OR 22 element, the output of which is connected to the input. a pulse generator 19, the output of which is the third output of the former 17; for example, phase. connected to the counter input of the counter 25, the reset inputs of counters 23-25 are combined and are the first reset input of the phase voltage generator, the output of the counter 25 is the fourth output of the phase voltage generator 17, the analyzer 26 starts reading, containing the threshold element 27 and An RS flip-flop 28, the first input of the threshold element 27 being the information input of the analyzer 26 began to connect, the output of the threshold element 2 is connected to the S input of the RS flip-flop 28, the R input of which is the control 1 input of the analyzer 26 and the reads. The outputs of the RS flip-flop 28 are the outputs of the read analyzer 26, of the AND elements 29-32, the normal element 33, connected through the AND 34 element to the S input of the RS flip-flop 35, And 36 element connected with the counting input counter 37, the output of which is the S input of the RS flip-flop 38, the direct output of which is the control input of the display unit 39, and the inverse output is the first input of the AND 40, the second input of which is the output of the AND 41, and the output of the element 40 is the third input of the phase voltage generator 17.

In addition, the output of AND 36 is the S-input of RS flip-flop 42, the direct output of which is the second input of AND 41, and its first input is the direct output of RS-flip-flop 35, the output of AND 41 also enters the first input of the element OR 43, the second input of which is combined with the R-inputs of the trigger 35, 38, 42 and is connected with the first output of the control unit 6. The output of the OR element 43 is the R input of the counter 37. The first input of the AND element 36 is the direct output of the analyzer 26 of the read start, and the second is the first output of the phase voltage generator 17, and the first information output of the matrix photoreceiver unit 4 under 0

0

CL OG: K: Ci; i; ;:; i .- ,, ;;. , i; i: i J 29-31, the inverse 1 output of the analyzer 26 read start is connected to the second input of the setting of the phase voltage former 17, the control outputs of which from the first to the third are connected respectively to the second inputs of the elements 29-29, the third control output also connected to the first input of element 32, the second input of which is connected to the output of element 40. The codes of the elements 29 and 30 are connected respectively to the first and second control inputs of the photodetector unit 4, the outputs of elements 31 and 32 are connected to the first and second controls exhibiting an input information fragment isolation block 11, fourth control output 17 of the phase shaper podksho- chen voltage to the first input of the control unit 6, the third input of which is an input device Start.

The holographic zamggshayushchy device works as follows.

The signal, which is the input of the device, from the output of the start-up unit 7 of the control unit 6, receives a 0 signal, setting the RS flip-flop 8 and the distributor 10 synchro-1puls to the unified position, the same signal goes to the first start of the control unit 6, from where passes to the reset input of the phase voltage driver, to the second input of the analyzer 26 read start, to the second input of the TSHI element. 43, to the R inputs of the 35, 38 and 42 trigger. For my RS5 output

five

key to the first information input 40 of trigger 8 is the fourth output

block 11 of the information fragment, the information input of the analyzer 26 start reading and to the input of the threshold element 33. The output of the block 11 of the information fragment d5 is connected to the input of the analog-digital converter 12, the outputs of which are connected to the t-shaped inputs of the output 13 of the output, control signal The input of which is connected to the third output of the control unit 6. The second output of the photodetector unit 4 is connected to the second input of the control unit 6, the first output of which is connected to the first input of the phase voltage generator 17 and to the control input of the analyzer 26 start reading, the second output of the control unit 6 of the subblock 6 control, 1 from this the output turns on the pumping unit 5, connected to the scanning emitter 1, and the hologram illumination begins. A reconstructed image with a hologram and an identification mark is projected onto the strong photoreceiver unit 4.

The duration of the illumination is determined automatically by the central electrode, operating in the floating gate mode and providing. read total charge per line. This signal from the second output 55 of the photoreceiver unit 4 enters the T control unit 6 (input 1) and triggers the trigger 8, causing the unit 5 to turn off, a waiting generator 9 is started and the associated generator 9

50

five

control unit 6, by signal 1, pumping unit 5 is connected to this output, connected to scanning emitter 1, and the hologram illumination starts. A reconstructed image with a hologram and an identification mark is projected onto the strong photoreceiver unit 4.

The duration of the illumination is determined automatically by the central electrode, operating in the floating gate mode and providing. read total charge per line. This signal from the second output 5 of the photoreceiver unit 4 enters the 6 T control unit (input 1) and the trigger 8 is zeroed, causing the block 5 to turn off, the waiting generator 9 is started and the associated generator 9

0

the distributor 10 sync pulses, the signal from the second output of control unit 6 permits the passage of signals from the first, second and third outputs of the phase voltage generator 17 to the control inputs of the photoreceiver unit 4 and to the first input of the information fragment selection unit.

The information of the photodetector unit 4 is sequentially shifted to the output register, from which element by element is output to the selection block 11 of the information fragment, to the read start analyzer 26 and to the threshold element 33. In the read start analyzer 26, the threshold element 27 detects a single signal from the output of the 4-unit 4 The threshold element 33 detects a zero signal (lower than the threshold value). In the zero state of the trigger 28 in the analyzer 26 of the start of reading in the phase voltage imaging unit 17, the generator 19 is switched by a signal from. counter 24, the conversion module of which is equal to the number of elements with in the row of the photodetector unit 4.

A read start analyzer 26 for detecting the position of the identification signal on which the interrogation signal of the information array is generated. In order to control the state of the radiator, it is also necessary to estimate the linear size of the identification mark (the number of elements occupied by the identification mark must be less than a certain value P). When the first single signal is output from the photodetector unit 4, the threshold element 27 is triggered (for L Lf, op) 5, after which the trigger 28 switches to the state, and the signal from its direct cycle allows the pulse through the first output element 36 to pass 17 phase voltages., Which carry out element-by-element output of information from the photodetector unit 4. The number of single output signals is determined in counter 37, the recalculation module of which is set equal to P (the number of elements of the photosensitive area occupied by an identifying mark in which the information signals D1C1N signals are superimposed on each other).

0

0 d g

five

0

If the number of pulses arriving at the counting output of counter 37 has reached the recalculation module, then the counter will receive an overflow signal to the S input of the RS flip-flop 38, the direct output of which is the control input of the display unit 39 Failure of the transmitter, inverse trigger flip-flop blocks the passage through ele. Ment 40 is the read start signal to the third input of the driver 17 phase voltages. Reception of information by the block 11 in the information fragment is blocked.

If the number of pulses arriving at the counting input of counter 37 does not go out of the permissible value, then the counter does not lose the overflow signal and the RS flip-flop 38 will remain in the initial zero state. The RS flip-flop 42 switches to the one state by the first pulse from the output of the AND 36 element and indicates that the identification mark is registered. The threshold element 33 detects a zero signal from the output of the photoreceiver unit 4 (Lbpor) and upon detecting it after the identifying mark with the crayon element I 34 transmits a signal to the S input of the RS flip-flop 35, from the direct output of which the signal passes through the element 41 under the condition of single state RS-flip-flop 42, through the OR element 43 to the R-input of the counter 37 and to the second input of the element. And 40, the first input of which receives the enable signal from the inverted output of the RS-flip-flop 38.

The output of element 40 is the control third read start input for the phase voltage driver. This signal starts a read cycle, it permits the passage of control signals from generator 19 through element 32 to block 11 for extracting an information fragment, and also changes the period in phase generator 17. switching the generator 19, since the pulses from the generator 18 will pass through the element AND 20 and the counter 23 with the conversion module equal to the number of line elements on which the information array is projected. Informational signal; arrive at block 11 of the selection of the information fragment, whence the matrix of information signals of the fragment in the analog

The form is fed to the inputs of analog-to-digital converter 12, the outputs of which are connected to the information inputs of the output signal generator 13, where they are summed up in the adder 14, and the obtained value is compared with the fragment luminance threshold value. At the output of the threshold element 15, a value is obtained that corresponds to a single optical signal projected onto the processed fragment of the photoreceiver unit 4, which enters the device code on a sync pulse from the output 1 of the distributor 10 sync pulses. At the end of the polling of the photo receiving unit 4, a signal about the end of the cycle is given which is generated in the counter 25, the recalculation module of which is equal to the number of rows in the photodetector unit 4, and enters the control unit 6 to the input of the start-up unit 7, after which the operation cycle of the devices is repeated.

Claims (1)

Invention Formula A holographic memory device containing a scanning emitter, optically coupled through sequentially arranged collimator and holographic information carrier to a matrix photoreceiver unit, a pumping unit whose output is connected to the input of a scanning emitter, an information fragment selection unit, whose information input is connected to the first information output of the photoelement matrix unit , the control output of which is connected to the control input of the analyzer, the start of reading, the output of the In the information section, it is connected to the input of the analog-digital converter, the outputs of which are connected to the corresponding information inputs of the output signal generator, the output of which is the information output of the holographic memory, the second information output of the matrix photo-receiving unit is connected to the input the end signal of the control unit, the first output of which connected to the control input of the phase voltage generator, the second output - to the first inputs of the elements And from the first to the third, inverse The analyzer start output is connected to the input of the phase voltage generator setting, the control outputs from the first to the third are connected respectively to the second inputs of the elements And from the first to the third, a quarter of the control output of the phase voltage phase changer is connected to the first input the fourth element And, the outputs of the first and second elements And are connected respectively to the first and second control inputs of the matrix photodetector unit, the outputs of the third and fourth elements And are connected respectively The first control output of the phase voltage former is connected to the reset input of the control unit, the Start input of which is the Start input of the holographic storage device, which differs from In order to increase the reliability of the device, elements I from five to eighth are introduced into it, RS-flip-flops from first to third, a counter and a threshold element, using the first information output of the photoreceiver array array, are connected to To the left input of the threshold element, the second input of which is connected to the output of the threshold voltage source, the output of the threshold element is connected to the first input of the sixth element And, the second input of which is connected to the forward output of the analyzer, read start, the output of the sixth element And is connected to the S input of the second RS flip-flop, the first input of the fifth element And is connected to the first control output of the phase voltage transformer, the second input of the fifth element And is connected to the third output of the analyzer, the start of reading, the output of the fifth element And the connected to the S-input of the counter, the output of which is connected to the S-input of the first RS-flip-flop, the output of which is the control output of the holographic storage device, the output of the second RS-flip-flop connected to the first input of the seventh element AND, the first pch output of which is connected to the first input of the element OR the output of which is connected to the R-input of the counter, the exhaust, the fifth element AND is connected to the S-input of the third RS-flip-flop, the output of which is connected eleven to the second input of the seventh element And the second output of which is connected to the first input of the eighth element And, the second input of which is connected to the inverse output of the first E5-trigger output of the eighth element. And connected 1499403 12 to the second input of the fourth element AND and the third control input of the phase voltage generator, the first output of the control unit is connected to the R inputs of the first and third RS-flip-flops and the second input of the OR element. 1