Method for coherent laser beam combining with synchronous detection and apparatus for coherent laser beam combining with synchronous detection

FIELD: physics.

SUBSTANCE: apparatus for coherent laser beam combining includes a laser with a fibre amplifier and a system of splitters which splits the laser beam into N+1 optical channels, from which one reference channel and N amplifier channels are selected. The apparatus also has a piezoceramic phase modulator of the reference channel, a harmonic electric oscillation generator connected the phase modulator of the reference channel to form an electrical positive feedback and operating at natural resonance frequency of the piezoceramic modulator, N phase-shift piezoceramic elements of operating channels, a system for combining N laser beams, which includes N collimators of operating channels connected to the N phase-shift piezoceramic elements of operating channels. Furthermore, the apparatus has a collimator with a reference channel telescope, connected to the piezoceramic phase modulator of the reference channel, a divider plate, N photodetectors on which control optical signals of interference of the reference and operating channels fall, N synchronous detection units which include a key synchronous detector, the synchronisation input of which is connected to the harmonic electric oscillation generator and the signal input is connected to the output of the N-th control photodetector. The output of the key synchronous detector is connected to the N-th phase-shift piezoceramic element of the operating channel to form an electrical negative feedback.

EFFECT: faster operation of the system.

13 cl, 5 dwg

 

The technical field to which the invention relates.

The invention relates to the field of laser technology and can be used to create beams of coherent radiation with high power density. The invention can find application in various fields of technology and medicine that require the use of laser radiation with high power density. The level of technology

In the prior art it is known device coherent combining of laser beams, including specifying the laser system of divisors of the laser beam, an acousto-optic or electro-optic modulator of the reference channel, creating a shift in frequency in the reference channel, the Executive phase-shifting elements are electro-optic modulators operating channels, a separating plate, the photodetectors on each channel, which tracks the phase shift of the reference and working channels, heterodyne detectors the phase shift between the reference and the working channels of the communication system of local oscillators and actuators. The addition of laser beams occurs in the far field for a separating plate [patent US 7884997 B1 publ. 08.02.2011].

The disadvantage of this method and device is that as modulators of reference and working channels using acousto-optic and electro-optic modulators. These devices involve the exit of the optical fiber on the volume elements, what complicates the design of the system and leads to the inevitable power loss on the harmonization of fiber and bulk optics. Losses will be allocated on these devices that, at high power can lead to thermal destruction.

Information that reveals the essence of the invention

The problem to which the invention is directed, is to create a system for coherent combining multiple laser beams modulated by the phase of the reference channel and using synchronous detection to ensure the correlation of working and reference channels.

Technical result achieved during the implementation of the claimed invention is to obtain a coherent optical signal by adding multiple laser beams modulated by the phase of the reference channel and using synchronous detection to ensure the correlation of working and supporting channels with nonlinear increase in the density of radiation power; to improve the performance (response) of the system due to the modulation on the phase signal of the reference channel at low frequencies in the range of 10-40 kHz and use a one-piece fiber optic system, which also leads to reduction of power losses, improving the heat balance and simplification of the alignment system; to simplify the design of the system, which increases the e reliability; in reducing the cost of the device due to the use of inexpensive low-frequency electronic components.

The claimed technical result is achieved due to the fact that the way of coherent combining of N laser beam synchronous detection is characterized by the fact that the master laser with a fiber amplifier form a single-frequency narrow-band laser beam, which is divided into N+1 optical channels, of which there are 1 (one) of the reference optical channel and N workers amplification of optical channels, the radiation of the reference channel modulate the phase by using piezoelectric modulator connected to the harmonic generator of electrical oscillations with the formation of an electric positive feedback and working on the resonance frequency of piezoelectric modulator, and the radiation of N working channels serves on the N phase shifters piezoelectric elements, followed by the addition of modulated in phase, the part of the radiation of the reference channel with a part of the radiation of the N-th working channels allocated using a separating plate, then N control optical interference signals obtained as a result of the addition is converted into N electrical signals, which serves to signal inputs N key synchronous detectors at the entrances of synchronization is the key purpose of the synchronous detectors serves a reference electrical signal from the harmonic generator of electrical oscillations, N-th key of the synchronous detector in the form of the N-th electrical signal tracks the phase deviation of the N-th working channel from the phase of the reference channel and generates an output N-th electric negative feedback signal reflecting the phase shift between the mean phase reference signal and the phase of the N-th working channel, which serves to N-th managing the piezoceramic element, providing synphasicity single core and the N-th working optical signals.

Also the claimed technical result is achieved due to the fact that the device of the coherent addition of the N laser beam synchronous detection includes specifying the laser with a fiber amplifier that generates a single-frequency narrow-band laser beam, the system fiber couplers intended for dividing the laser beam into N+1 optical channels, of which there is one optical reference channel and N workers amplification of optical channels, piezoelectric modulator phase of the reference channel, the harmonic generator of electrical oscillations connected with the piezoelectric modulator phase of the reference channel with the formation of an electric positive feedback and working on the resonance frequency of piezoelectric modulator, N phase shifters piezoceramic elements working channels, the system SL is the supply of N laser beams, including N collimators working channels connected to the N phase-shifting the piezoelectric elements operating channels, the collimator with the telescope reference channel, coupled with the piezoelectric modulator phase of the reference channel, the separating plate N control photodetectors that receive the allotted separating plate control optical signals of the interference of the reference and working channels, N key synchronous detectors, the synchronization inputs which are connected to the harmonic generator of electrical oscillations, and the signal inputs connected to the outputs of the N-th control photodetectors, and the key outputs of the synchronous detectors are connected to the N phase-shifting the piezoelectric elements operating channels with the formation of the opto-electric negative feedback.

Use unbreakable fiber optical system, including a system of taps and fiber amplifiers, in which the integrated piezoelectric modulators radiation of the reference channel and control elements operating channels, does not require the Assembly system coordination and alignment of optical elements, thus providing the necessary thermal regime of these elements. The use of phase modulation in the reference channel and the synchronous detection allows you to work on DOS is low enough frequency of tens of kHz and thus to obtain a fast response of the system in units of milliseconds. The inclusion of the generator harmonic (sinusoidal) oscillations in positive feedback with piezoelectric modulator phase reference channel running on the first resonance frequency, provides synphasicity electrical and mechanical signals and, accordingly, electric clock and optical phase modulation in the reference channel.

In addition, in the particular case of the invention prior to addition of the radiation of the working channels and the reference channel, the radiation of the N working channels reinforce and correct the polarization of radiation.

In addition, in the particular case of the invention prior to addition of the radiation of the working channels and the reference channel increase the diameter of the laser beam of the reference channel.

In addition, in the particular case of the invention the device of coherent combining further includes N fiber amplifiers radiation working channels connected to the N phase-shifting the piezoelectric elements.

In addition, in the particular case of the invention the device of coherent combining further includes a phase shifter clock and shaper rectangular reference signal for the synchronous detector.

In addition, in the particular case of the invention the device of coherent combining further includes pre the amplifier, connected to the N-th control photodetector, selective bandpass preamplifier, the input connected to the output of the preamplifier and high voltage amplifier.

In addition, in the particular case of the invention the device of coherent combining further includes N polarization controllers connected to N fiber amplifiers.

In addition, in the particular case of the invention the fiber amplifier radiation of operating channels is dvuhseriynoy fiber in a single shell length of 15 m, rolled into a ring with a diameter of 150 mm, with one core - passive, multimode, with a diameter of 50 μm, and the other active, alloy ions Yb3+, singlemode, with a diameter of 6 ám.

In addition, in the particular case of the invention piezoelectric modulator phase of the reference channel and each of the phase-shifting piezoelectric elements operating channels is made in the form of a hollow piezoelectric cylinder, on which are wound coils of fiber optic, and piezoelectric modulator phase of the reference channel includes 4 round fiber, and the phase-shifting the piezoceramic element of the working channel includes 10 turns of fiber.

In addition, in the particular case of the invention between the phase-shifting the piezoelectric elements are installed vibration isolators.

The AOC is e, in the particular case of the invention the separating plate is made with a division ratio of 1/25.

In addition, in the particular case of the invention collimators installed in the holders so that the distance between the axes of the collimators 4 mm and axis intersect at one point at a distance of 4 meters from the holder.

The implementation of the invention

Figure 1 presents a schematic diagram of a system of coherent combining of laser beams with synchronous detection;

figure 2(a) shows the field distribution from 1 (one) fibre channel and 2(b), the laser power of 1 (one) of the optical channel;

figure 3(a) shows the field distribution from 2 (two) optical channels and 3(b), the laser power of 2 (two) optical channels:

figure 4(a) shows the field distribution from 3 (three) optical channels (rows) and 4(b), the laser power of 3 (three) optical channels;

figure 5(a) shows the field distribution of 7 (seven) optical channels (in dense hexagonal packing) and 5(b), the laser power of 7 (seven) optical channels.

To ensure coherent combining of multiple working channels of optical radiation it is necessary to know the phase of each of the channels and be able to manage this phase. To solve this problem we use Odie the reference channel and relatively it synced all working channels.

The system is coherent combining of laser beams [1] includes specifying the laser 1 fiber amplifier (not shown), forming a single-frequency narrow-band laser beam, the system fiber couplers 2, designed to divide the laser beam into N+1 optical channels, of which there are 1(one) of the reference optical channel, and N workers amplification of optical channels, piezoelectric modulator 3 phase reference channel N phase-shifting piezoelectric elements 4 working channels connected by fiber-optic line 21N fiber amplifiers 5 radiation working channels, the system coherent combining of laser beams, comprising N collimators 6 working channels connected by fiber-optic line 21N fiber amplifiers 5, the collimator 7 reference channel, coupled by the optical fiber 21with the piezoelectric modulator 3 phase reference channel and the telescope 8, a separating plate 9, N control photodetectors 10, N polarization controllers (not shown)placed respectively between the fiber amplifier 5 and the collimator 6, the control unit, the N blocks of synchronous detection. The control unit switches the generator 11 harmonic electric vibrations, which, through the amplifier 12 is connected to a piezoelectric modulator 3 phase is pornoho channel with the formation of an electric positive feedback and maintain the generator at its own resonant frequency. Additionally, the control unit may include a phase shifter reference signal and the shaper rectangular reference signal (not shown). Collimators 6 is installed in the holder (not shown) in such a way that their axis were separated by 4 mm and intersect at a single point at a distance of 4 meters from the holder. In an experiment, these distances were chosen so as to obtain the far-eld system interference stripes and spots. In order to obtain a single spot, it is necessary to reduce the distance between the axes of the collimators and/or remove the point of intersection of the axes.

Each of the N blocks of the synchronous detection includes key synchronous detector 13, the synchronization input of which is through the preamplifier 15 and selective bandpass preamplifier 16 is connected to N-th control photodetector 10, and the signal input is connected to the generator 11 harmonic electric vibrations. Exit key the synchronous detector 13 is connected to N-th phase shifting piezoelectric element 4, which provides negative feedback phase, reflecting the phase shift between the reference optical channel and N-th working optical channel.

System 2 fiber couplers in the proposed version of the Rea is Itachi invention consists of 3 (three) stages of divisors. The first stage divides the radiation of the master laser 1 on 2 (two) optical channel, the second cascade-4 (four), the third cascade of 8 (eight). Each of the seven factors is a fused fiber multiplexer (Kapler) type OLCPL-S-SD-22-106-50-25-NC with a division ratio of 50/50 at the wavelength of 1064 nm. One of the eight optical channels identified as the reference channel, the remaining seven optical channels identified as working. System fiber couplers can be designed in such a way as to ensure the division of the laser beam on an unlimited number of channels.

Piezoelectric elements 3 and 4 represent the coil diameter of 85 mm, consisting of a hollow piezoelectric cylinder, on which are wound coils of optical fiber 21. Piezoelectric modulator 3 phase reference channel includes 4 turns of the optical fiber, the phase-shifting Piezoelectric element 4 of the working channel includes 10 turns of the optical fiber. To exclude spurious acoustic coupling between N Fossdyke the piezoelectric elements 4 are installed vibration isolators (not shown).

The optical fiber amplifier 5 is dvuhseriynoy fiber in a single shell (GTWave fiber) length of 15 m, rolled into a ring with a diameter of 150 mm Single core - passive, multimode, with a diameter of 50 μm, using the tsya to enter the pump. The other is active, alloy ions Yb3+single-mode, with a diameter of 6 ám.

To correct the polarization of the radiation in the working channels after fiber amplifier 5 can be set to a polarization controller (not shown)

The operation of the device is as follows

Specifying the laser 1 fiber amplifier (not shown) generates a single-frequency narrow-band laser beam, which system 2 fiber couplers, in the particular case of the invention is divided into eight optical channels, of which there is one reference optical channel and seven working optical channels. The radiation of the reference channel serves on the piezoelectric modulator 3 phase, piezoceramic cylinder which is connected to the generator 11 harmonic electric vibrations with the formation of an electric positive feedback and working as a result of this positive feedback on its own resonance frequency of the piezoelectric modulator. The radiation in the reference channel is modulated in phase with modulation depth of from a fraction of a wavelength to several wavelengths due to mechanical changes in the length of the optical path with a modulation frequency of about 11 kHz, which corresponds to the first resonance frequency of the piezoceramic cylinder modulator hisenemies length of the optical path is achieved by the optical fiber 21wound on a piezoceramic cylinder changes its length (lengthened or shortened) by expansion or compression of the piezoceramic cylinder receiving the electrical signal from the generator 11. The radiation of the N-th working channel serves on the N-th phase shifting piezoelectric element 4, and then reinforce by means of fiber optic amplifiers 5. If necessary adjust the polarization of radiation in the working channel using polarization controllers (not shown)installed after fiber amplifier 5. After amplification of the radiation of the N-th working channel through the collimators 6 is displayed on the separating plate 9. Modulated by the phase of the radiation of the reference channel with the piezoelectric modulator 3 phase through the collimator 7, connected with the telescope 8 displays the expanded beam diameter of 10-12 mm in a separating plate 9 with a division ratio of 1/25, which is the sum (Union) of the radiation of the reference channel with the radiation of the N-th working channel. A separating plate 9 skips most of the emission of N working channels (96%) and a smaller part of the radiation of the reference channel in the far field (the separating plate), where the coherent addition of operating channels, and misses most (96%) of the reference radiation and the smaller part (4%) is zlecenia each of the N working channels, which, through the collimators (not shown) is supplied to the N control photodetectors 10. The control optical signal (light) interference, comprising part of the radiation of the N-th working channel and the common reference channel, gets the corresponding N-th photodetector 10, which converts it into an electrical signal. The electrical signal from the N-th control of the photodetector 10 through the pre-amplifier 14, which amplifies the electric signal, and selective bandpass preamplifier 15, which cuts off high and low acoustic frequency, is fed to the signal input of the N-ro key synchronous detector 13, the synchronization input receives a reference electrical signal from generator 11. Key synchronous detector in the form of the N-th electrical signal tracks the phase deviation of the N-th working channel from the phase of the reference channel and generates an output electrical signal of negative feedback, which reflects the phase shift between the mean phase reference signal and the phase of the N-th working channel. The electrical signal output from the key N synchronous detector 13 through a high-voltage amplifier 16 is supplied to N-th phase shifting piezoelectric element 4 of the working channel, which provides synphasicity N-th working and reference optical channels due to the alignment of the optical length of the protected area the fibers of the working channel to the reference channel. Changing the length of the optical path is achieved in that the optical fiber 21wound around a piezoelectric cylinder of the phase-shifting element 3, changes its length (lengthened or shortened) by expansion or compression of the piezoceramic cylinder receiving the electric signal output from the key of the synchronous detector 13. To achieve a larger dynamic range of the phase shift of the phase-shifting phytoceramides element 4 has 10 turns of the optical fiber, which allows for the variation of the phase of several hundred wavelengths when the control voltage 10th Century

To implement the tracking phase shift between the average value of the phase reference channel and the phase of the N-th working channel key synchronous detector 13 is configured to implement the following mathematical model.

Signal interference can be written as:

P=ACos(BSin(t+φ)+C)+D (1)

where P is the signal interference [W];

A - the amplitude of the interference [W];

B is the amplitude modulation of the reference channel phase [rad];

φ is the phase shift in time of the mechanical modulation and sync [rad];

C DM the IG phase average phase of the reference and the working channels [rad];

D - constant stand [W];

t is the time normalized by the frequency modulation [2π/period reference signal].

Algorithm key synchronous detector 13 is described by the following formula:

S=0πACos(BSin(t+φ)+C)dt-π2πACos(BSin(t+φ)+C)dt(2)

After simplification we get:S=-2ASin(C)0πSin(BSin(t+φ))dt(3)

Misalignment of the phase reference and the N-th working channel went out the sign of the integral. Thus, we can conclude that the signal from the key of the synchronous detector 13 can be used for stabilizing negative feedback, which will support the phase shift between the reference and the nth working channel zero, thus the sensitivity of key synchronous detector 13 will depend on the absolute value of the integral. Was numerically calculated integral by the formula (3) when B is in the range from 0 to 1500 radians (250 wavelengths) and for different φ from 0 to 2π). For small values of the integral is almost straight out of scratch. The first maximum at the value B=1.98 happy to continue oscillating slowly decays and crossing the zero function. Function Sin(B·Sin(t+φ)) is odd and repetitive with a period of 2π. The integral is maximum at φ=2π·t (n - integer), the minimum (and the same in absolute value) when φ=2π·n+π and vanishes when φ=π·n+π/2. Thus, the maximum sensitivity of the system, implemented using synchronous detection, with the amplitude modulation of the reference channel phase, approximately 2 rad (1/3 wavelength), and in the absence of the phase shift between the mechanical vibrations of the piezoelectric modulator 3 of the reference channel and the electric is increasignly. The latter is ensured by the fact that as the frequency control element generator 11 of the reference electrical signal is not an external source, and the piezoelectric modulator 3, included in the positive feedback generator 11.

On the graph presented in figure 2(b)shows that the power density of the radiation of one optical channel is about 0.2 W/cm2the power density of the radiation of two optical channels is about 1 W/cm2(figure 3(b), the radiation power density of the three optical channels is approximately 1.25 watts/cm2(figure 4(b)), the power density of the radiation of the seven optical channels leaves about 3 W/cm2(figure 5(b)), shows that the power density increases not linearly.

Implementation of the invention allows to form a coherent optical signal by summing beam of laser radiation with high power density in a nonlinear increase in the density of radiation power.

1. The method of coherent combining of N laser beams with synchronous detection, characterized in that: the master laser with a fiber amplifier form a single-frequency narrow-band laser beam, which is divided into N+1 optical channels, of which there are 1 (one) of the reference optical channel and N workers amplifying optical channel is in, the radiation of the reference channel modulate the phase by using piezoelectric modulator connected to the harmonic generator of electrical oscillations with the formation of an electric positive feedback and working on the resonance frequency of piezoelectric modulator, and the radiation of N working channels serves on the N phase-shifting piezoelectric elements, followed by the addition of part modulated by the phase of the radiation of the reference channel with the parts of the radiation N-x number of channels allocated using a separating plate, then N control optical interference signals obtained as a result of the addition is converted into N electrical signals, which serves to signal inputs N key synchronous detectors, with the inputs of the synchronization key of the synchronous detectors serves a reference electrical signal from the harmonic generator of electrical oscillations, N key synchronous detector in the form of the N-th electrical signal tracks the phase deviation of the N-th working channel from the phase of the reference channel and generates at the output the N-th electric negative feedback signal reflecting the phase shift between the mean phase reference signal and the phase of the N-th working channel, which serves to N-th phase shifting piezoelectric element, ensuring the th synphasicity N-th working and reference optical signals.

2. The method according to claim 1, characterized in that before the addition of radiation of the working channel and the reference channel, the radiation of N working channels reinforce and correct the polarization of radiation.

3. The method according to claim 1, characterized in that before the addition of radiation of the working channel and the reference channel increase the diameter of the laser beam of the reference channel.

4. The device of the coherent addition of the N laser beams with synchronous detection, including laser with a fiber amplifier that sets a single-frequency narrow-band laser beam, the system fiber couplers intended for dividing the laser beam into N+1 optical channels, of which there is one optical reference channel and N workers amplification of optical channels, piezoelectric modulator phase of the reference channel, the harmonic generator of electrical oscillations connected with the piezoelectric modulator phase of the reference channel with the formation of an electric positive feedback and working on the resonance frequency of piezoelectric modulator, N phase-shifting piezoelectric elements operating channels, the system adding the N laser beams, including N collimators working channels connected to the N phase-shifting piezoelectric elements operating channels, the collimator with the telescope reference channel, coupled with pies the ceramic phase modulator reference channel, a separating plate N control photodetectors that receive the allotted separating plate control optical signals of the interference of the reference and working channels, N key synchronous detectors, the synchronization inputs of which are connected by harmonic generator of electrical oscillations, and the signal inputs connected to the outputs of the N-x test photodetectors, and the key outputs of the synchronous detectors are connected to N-th phase shifting piezoelectric elements operating channels with education optoelectrical negative feedback.

5. The device according to claim 4, characterized in that it further includes N fiber amplifiers radiation working channels connected to the N phase-shifting the piezoelectric elements.

6. The device according to claim 4, characterized in that it further includes a phase shifter clock and shaper rectangular reference signal for the synchronous detector.

7. The device according to claim 4, characterized in that it further includes a preamplifier connected to the N-th control photodetector, selective bandpass preamplifier, the input connected to the output of the preamplifier and high voltage amplifier.

8. The device according to claim 4, characterized in that it further includes N polarization controllers connected to N fiber us what literami.

9. The device according to claim 4, characterized in that the fiber amplifier radiation of operating channels is dvuhseriynoy fiber in a single shell length of 15 m, rolled into a ring with a diameter of 150 mm, with one core - passive multimode diameter of 50 μm, and the other active, alloy ions Yb3+single-mode diameter of 4 microns.

10. The device according to claim 4, characterized in that the piezoelectric modulator phase of the reference channel and each of the phase-shifting piezoelectric elements in the form of a hollow piezoelectric cylinder, on which are wound coils of fiber optic, and piezoelectric modulator phase of the reference channel includes 4 round fiber, and the phase-shifting the piezoceramic element of the working channel includes 10 turns of fiber.

11. The device according to claim 4, characterized in that between the phase-shifting the piezoelectric elements are installed vibration isolators.

12. The device according to claim 4, characterized in that the separating plate is made with a division ratio of 1/25.

13. The device according to claim 4, wherein the collimators are installed in the holders so that the distance between the axes of the collimators 4 mm and axis intersect at one point at a distance of 4 meters from the holder.



 

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2 cl, 4 dwg

FIELD: physics.

SUBSTANCE: apparatus includes, arranged in series on an optical axis, a mutual polarisation rotator which rotates the polarisation plane of transmitted radiation by an angle φ and a compensating optical element placed behind an absorbing optical element. The compensating element is an optical element having, for the same parameters of laser radiation, thermally induced depolarisation γ1 approximately equal to γ0: γ1 (P1, Q1, k1, ξ1, α1, L1, W) ≈ γ0 (P0, Q0, k0, ξ0, α0, L0, W), where P and Q are thermo-optical parameters of the element, k0 is the thermal conductivity coefficient of the element, ξ0 is the optical anisotropy parameter of the material of the element, α0 is the absorption coefficient of the material of the element, L0 is the length of the element, W is the laser radiation power. At least one of said parameters, from which γ1 depends, is not equal to the corresponding parameter γ0, and angle φ of the mutual polarisation rotator and the distinctive parameters of the compensating element are determined by the selection of the material of the compensating element and the condition for minimum total thermally induced depolarisation in the absorbing element-mutual polarisation rotator-compensating element system.

EFFECT: possibility of compensating for thermally induced depolarisation in any predetermined laser absorbing optical element.

4 cl, 3 dwg

FIELD: physics.

SUBSTANCE: described is an artificial microoptic system and a protective device, which include a planar image formed from a matrix or a pattern of pictograms and a matrix of focusing elements; the system forms at least two different artificial images, owing to which one artificial image serves to regulate or control the degree of visibility of the other artificial image. In a typical form, the matrix of pictograms forms a planar artificial image, while interaction of the matrix of focusing elements with the matrix of pictograms forms a separate artificial enlarged image which serves to control the field of view of the planar image, thus serving to regulate or control the degree of visibility of the planar image. Therefore, the planar image visually emerges and disappears, or is turned on and off, depending on the viewing angle of the system.

EFFECT: improved system.

41 cl, 158 dwg

FIELD: physics.

SUBSTANCE: pulsed laser radiation source has at least one pulsed laser, an optical means for summation of radiation and a focusing system. The source further includes a driving generator whose output is connected to the input of the pulsed laser, and the output of the pulsed laser is optically connected in series to an optical switch, a matching unit, an optical delay means and the optical means for summation of radiation and then further with the focusing system, wherein the output of the driving generator is connected to the control input of the optical switch.

EFFECT: high output optical power of laser radiation pulses.

2 dwg

FIELD: physics.

SUBSTANCE: image display system includes an array of microstructured pictogram elements made for combined formation of an image or information, and structured coating material applied on at least part of the surface of a layer of microstructured pictograms. Observation or reading using a magnifying device is possible. The array of microstructured pictogram elements is embedded in a pictogram layer. Structuring of the coating material makes up a region where there is coating material and regions where there is no coating material. The artificial imaging system includes an array of focusing elements and an imaging system which includes an array of microstructured pictogram elements which is embedded in the pictogram layer. The array of focusing elements and the imaging system interact in order to form at least one artificial optical image. Structured coating material is used, which is applied on at least part of the surface of the microstructured pictogram layer. Structuring of the coating material makes up a region where there is coating material and regions where there is no coating material.

EFFECT: enabling open authentication of currency, documents, industrial articles and products, and visual magnification of industrial articles, products and packaging.

45 cl, 52 dwg

FIELD: physics, optics.

SUBSTANCE: apparatus includes a laser radiation splitter. The splitter splits polarised radiation from an external source into basic and reference radiation. Basic radiation is directed onto a second splitter where it is split into N channels and amplified by amplifiers in each channel. Part of the radiation is collected by a semitransparent mirror(s). A control beam is formed, compared with reference radiation and then converted to an electric signal. The control signal for phase adjustment modules is calculated based on the signal parameters using a computation unit. Phase adjustment is carried out using N phase adjustment modules lying after amplifiers which perform phase shift in each channel using cyclic control signals. The value of each control signal in each of the N channels is determined separately via summation of the signal which is determined from shift of interference fringes in the plane of the array of a multichannel photodetector with the signal determined from the results of measuring intensity of the resultant radiation. Beams of control and reference radiation fall on the multichannel photodetector at a small angle with respect to each other. Resultant radiation is obtained when all beams of control radiation are focused on a one-channel photodetector using a lens.

EFFECT: obtaining high-power monochromatic coherent radiation.

5 cl, 3 dwg

FIELD: medicine.

SUBSTANCE: group of inventions relates to medical equipment, namely, to laser probes and their combinations, applied in ophthalmology. Probe contains irradiating optic fibre for light beam irradiation, optic system, located on the irradiation side of irradiating optic fibre, and two or more receiving optic fibres, located opposite to irradiating optic fibre. Optic system contains diffractive surface. Light beam, irradiated by irradiating optic fibre, is diffracted into two or more diffracted light beams, focused in plane, parallel to diffraction surface. Receiving ends of each of two or more receiving optic fibres, are intended for reception of light beam, diffracted by optic system, are located in plane, parallel to diffraction surface. Another version of implementation is ophthalmologic laser probe, containing irradiating optic fibre and optic system, located on irradiation side of irradiating optic fibre. Optic system is made in the same way as in the previous version. Connection for laser probe contains case, optic system, located in case, first connecting link, located on one side of optic system; and second connecting link, located on the other side of optic system. Optic system contains diffraction surface, each of two or more diffracted light beams is focused in plane, parallel to said surface.

EFFECT: application of group of inventions will make it possible to reduce operation time due to probe construction which makes it possible to form multipoint laser beam.

27 cl, 16 dwg

FIELD: physics.

SUBSTANCE: protective coating has a layer of polymer material with shape memory, having a surface made of microlenses, where each microlens is associated with one of a plurality of images on the protective coating. The layer of polymer material with shape memory is sensitive to external stimulating effect, for example to temperature, a solvent or moisture, owing to transition from a first state in which the optical property of the microlens has a first value to a second state in which the optical property of the microlens has a second value. The microlenses have refracting surfaces which transmit light to positions in the protective coating, yielding a composite image from images formed on the protective coating when the layer of polymer material with shape memory is in one of a first or second state.

EFFECT: invention provides change in optical properties of the article as a result of the external effect.

9 cl, 19 dwg

FIELD: physics.

SUBSTANCE: disclosed microoptical systems for artificial magnification include a pictogram matrix; and a matrix of pictogram focusing elements (microlens); where the matrix of pictogram focusing elements and the pictogram matrix arranged relative each other in such a way that at least one artificially magnified image having a motion effect is provided. Each of the said pictogram matrices and matrices of pictogram focusing elements have their own separate design features, for example the matrix of pictogram focusing elements can have thickness less than 50 micrometres and/or the effective diametre of the base of pictogram focusing elements can be less than 50 micrometres.

EFFECT: possibility of using disclosed engineering solutions on objects for everyday use, which are subjected to multiple mechanical effects and deformations without breaking down and deterioration of characteristics of microoptical system for artificial magnification with provision for high magnification and obtaining a clear image of protective micro-structured elements.

103 cl, 33 dwg

FIELD: physics.

SUBSTANCE: apparatus has at least one display apparatus, a total internal reflection (TIR) optical element connected to a drive and at least one optical path distributing optical element. The TIR optical element can form an optical path for transmitting an image of the environment directly from the environment to at least one optical path distributing optical element. The optical path distributing element has a surface with controlled TIR and can form an optical path for transmitting the image of the environment from the TIR optical element to at least one eye of an observer, and can also form an optical path for transmitting a virtual image from the display apparatus to at least one eye of an observer.

EFFECT: reproduction of a virtual image and an image of the environment, low power consumption and weight.

22 cl, 5 dwg

FIELD: physics.

SUBSTANCE: mirrors/filters are placed in space so as to create a collinear matrix group of rectangular beams through successive reflections and/or transmissions from several optical frequencies emitted by a defined number of radiation sources. The top step consists of matrix of mirrors/filters with size m x n in p items superimposed with each other. The bottom step is a matrix from m mirrors/filters built into p rows with possibility of addressing outgoing beams to columns of matrices of the top step. The mirrors/filters of the matrices have characteristics which enable transmission of spectra of optical frequencies of the incoming beam or part of it and/or transmission of the spectra of optical frequencies of the incoming beam or part of it to the next mirror/filter.

EFFECT: optimisation of the process of frequency-address light beam routing.

5 cl, 11 dwg

FIELD: physics.

SUBSTANCE: method involves image preprocessing using a video processor 13 to eliminate geometric distortions, resulting from the geometry of the optical system; formation of an image of the cabin space on a monitor screen 1 and projection using a reproduction lens 2 onto a holographic diffuser 3, which is an assembly of two diffusers (4, 6), turned about each other and joined by a layer of immersion transparent substance 5, and which forms a scattering indicatrix so as to provide a given viewing area with the required image contrast. Principal beams are directed near the optical axis of the system using a collective lens 7, placed in front of the holographic diffuser. The image is then directed to the viewing area of the driver 12 using a holographic beam splitter 9, placed on the windscreen 10.

EFFECT: increased reliability and provision for safe driving conditions.

2 cl, 4 dwg

FIELD: physics.

SUBSTANCE: metre of radiation intensity in pulse optical quantum oscillators comprises double-beam interferometre by Rozhdestvenskiy with two dead and two semi-transparent mirrors. In its first optical branch - signal one - magnetooptical cell of Cotton-Mouton and crossed nicol are serially installed, and in the second one - reference one - there are the following components serially installed - phase plate, photometric wedge and half-wave plate. To inlet of interferometre by Rozhdestvenskiy via Polaroid there is a single-frequency single-mode optical quantum oscillator of continuous action connected. Radiation of measured pulse optical quantum oscillator via quarter-wave plate and diaphragm radiates magnetooptical cell of Cotton-Mouton in direction perpendicular to distribution of laser radiation in it from single-frequency single-mode optical quantum oscillator of continuous action. Outlet of interferometre by Rozhdestvenskiy is connected to inlet of homodyne photodetector based on compound "cadmium-mercury-tellurium" cooled by liquid nitrogen, electric outlet of which is connected to inlet of spectrum analyser.

EFFECT: provision of linear assessment of intensity of ultra-short and powerful pulses of laser radiation of optical quantum oscillators that operate in modes with modulated Q value or synchronisation of modes.

1 dwg

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