Multielement terahertz radiation generator
SUBSTANCE: multielement terahertz radiation generator includes test sample, femtosecond laser, multielement emitter where element emitter is made in the form of crystal semiconductor with sputtered metal mask forming sharp laser illumination gradient for crystal semiconductor layer. On the boundary of illuminated and shaded parts of semiconductor layer, a sharp gradient of photoexcited charge carrier concentration is formed parallel to the semiconductor surface. In addition the device includes elliptical mirror forming a focused terahertz radiation beam, while multielement emitter includes a raster of cylindrical microlenses distributing laser radiation between element emitters and illuminating only those semiconductor layer areas involved in terahertz radiation generation. The metal mask is made in the form of flat metal stripes.
EFFECT: increased power of terahertz radiation, possible application of small test samples.
3 cl, 2 dwg
The device relates to pulse generators broadband electromagnetic radiation in the terahertz frequency range, based on conversion of femtosecond laser radiation. Such generators are used to generate the terahertz spectrometers to study the properties of substances and materials in the terahertz region of the electromagnetic spectrum. Such devices should have a high conversion efficiency of laser radiation in the terahertz. To solve specific problems using the powerful radiation it is necessary to use materials having a high radiation resistance. The device should have small dimensions to create a portable spectrometers.
Known technical solutions used in the construction of a photoconductive antennas: TERA15-FC produced by the company "Menio Systems, Germany http://www.menlosvstems.com): G10620-11, G10620-12, G10620-13, manufactured by the company "Hamamtsu, Japan (http://ip.hamamatsu.com). Devices are pulse generators broadband electromagnetic radiation in the terahertz frequency range, based on conversion of femtosecond laser radiation, and represent a photoconductive antenna, installed in a single housing with a silicon lens. Photoconductive antennas represent the Oh deposited on the surface of the semiconductor electrodes. Generation of terahertz radiation occurs when the absorption of femtosecond laser radiation in the semiconductor and related to the appearance in it of a pulsed photocurrent due to the drift of photoexcited charge carriers along the surface of a semiconductor in an electric field applied to the electrodes. The maximum beam of terahertz radiation perpendicular to the direction of drift and the semiconductor surface. Installed silicon lens colliery or focuses the THz radiation.
Such devices have increased noise, because of fluctuations in the external electric field is moved in the terahertz signal and degrade the noise performance of the oscillator as a whole. Also photoconductive antennas are characterized by the saturation power of the generated THz radiation with increasing laser intensity. This saturation is due to shielding of the applied electric field excited charge carriers in the semiconductor.
A disadvantage of the known technical solutions is that in photoconductive antennas is the need of the application of the external electric field created by the electrodes on the semiconductor surface. In addition, between the electrodes flows photocurrent proportional to the intensity of the laser radiation. Electric power to ora is determined by the product of the intensity of applied electric field and the strength of the photocurrent, is converted into heat which must be removed from the device. This determines the maximum laser power and the maximum amplitude of the applied voltage to avoid overheating and/or electrical breakdown of the device.
Known technical solution based on a crystalline semiconductor that is used in pulse generators broadband electromagnetic radiation in the terahertz frequency range, based on conversion of femtosecond laser radiation. The technical solution described in the publication: Vitalij L. Malevich a, Ramunas Adomavicius, Arunas Krotkus, "THz emission from semiconductor surfaces", Science Direct, C.R. Physique 9 (2008) 130-141. Generation of terahertz radiation occurs when the absorption of femtosecond laser radiation in the crystalline semiconductor and related to the appearance in it of a pulsed photocurrent due to the diffusion of photoexcited charge carriers (the effect of Dember) and their drift in the internal electric field of the crystalline semiconductor.
A disadvantage of the known technical solutions associated with a low coefficient of conversion of laser radiation into terahertz radiation, namely the output of the generated terahertz radiation from the near-surface layer of the crystalline semiconductor outward. The low conversion efficiency of mo is but to explain as follows. The direction vectors of the drift and diffusion of photoexcited charge carriers perpendicular to the surface of the semiconductor and collinear with the vectors of the electrical field vector of the electric field due to the effect of Dember, respectively. Thus, the directional diagram of the terahertz radiation is perpendicular to these vectors and parallel to the surface of the semiconductor. Due to the large refractive index of the semiconductor is only a small part of terahertz radiation is derived from generator, reflected from its surface on the inner side. A second disadvantage of the known technical solutions associated with the saturation power terahertz radiation with increasing laser intensity. In the local area illuminated by the laser radiation, can be created in a finite number of photoexcited charge carriers involved in the generation of terahertz radiation, and thus a further increase of the laser power does not increase power terahertz.
Known technical solution used in pulse generators broadband electromagnetic radiation in the terahertz frequency range, based on conversion of femtosecond laser radiation (Patent WO 2010/142313 "A passive terahertz radiation source, the IPC H01S 1/02, G02f 2/02, priority from 201012-16), selected as a prototype. The generator of terahertz radiation includes a source of pulsed laser radiation in the form of a laser emitter, comprising at least one elementary emitter, which is a layer of crystalline semiconductor, a portion of the surface which is illuminated by pulse laser radiation, and under the action of this radiation on the border of lighted and unlighted fields parallel to the surface of the crystalline semiconductor is formed a sharp concentration gradient of the photoexcited charge carriers. Generation of terahertz radiation based on the photoelectric effect of Dember, which can be described as follows. The charge carriers diffuse to the area of lower concentration to form a pulsed diffusion current. A significant difference in the mobility of positive and negative charge carriers leads to their spatial separation and the formation of the electric field intensity vector. The change in the diffusion current in the electric field causes the emission of electromagnetic pulse.
The spectral composition and the pulse duration are determined by the parameters of laser radiation and the properties of the crystalline semiconductor and correspond to the terahertz frequency range. Generator deprived drawback associated with the withdrawal of those who egertova radiation from the layer of crystalline semiconductor output, since the directional diagram of the terahertz radiation is perpendicular to the vector of the electric field due to the effect of Dember, and accordingly the surface of the crystalline semiconductor. In accordance with the law of reflection Fresnel conclusion of terahertz radiation perpendicular, i.e. at an angle of 90 degrees to the surface of the crystalline semiconductor is the most effective since it has the lowest loss at the reflection of terahertz radiation from the inner surface of the crystalline semiconductor. Thus, you receive the highest possible power terahertz radiation.
The use of the photoelectric effect of Dember for generating terahertz radiation does not require the use of an external electric field, the fluctuations of which are transferred to the noise terahertz radiation and degrade the signal-to-noise oscillator as a whole. Also because of this not happening saturation power of the generated THz radiation with increasing intensity femtosecond laser radiation associated with the screening of the applied electric field the photoexcited charge carriers in the crystalline semiconductor.
Generator, consisting of a set of elementary emitters (multielement oscillator)has a greater conversion rate femtosec ndogo laser radiation in the terahertz, than the generator, consisting of a single elementary emitter (singleton generator), as multi-element generator deprived drawback associated with the saturation power terahertz radiation with increasing laser power. Power femtosecond laser radiation is distributed in proportion to the number of elementary emitters involved in the generation of terahertz radiation, and in every elementary emitter its value becomes below the threshold for inclusion mechanism of saturation. Total power terahertz radiation multielement oscillator is the sum of the capacities emitted from each of its elementary emitter. Thus, the power of the terahertz radiation can be significantly increased compared with singleton generator by increasing the power femtosecond laser radiation and the absence of this saturation.
In the prototype described in the scheme of the multichannel generator. It is a crystalline semiconductor layer with a spray to the surface of a periodic structure consisting of metal strips. The profile strips, wedge-shaped. When illuminated by laser radiation part of it is reflected from a metal strip, and the remaining part is absorbed in the crystalline semiconductor. The thicker end of the metal strip is fully isolate a crystalline semiconductor light laser radiation and forms a sharp gradient illumination of the crystalline semiconductor. A thinner edge is translucent and forms a smooth gradient. The faster gradient illumination with laser light, the sharper the density gradient is formed of photoexcited charge carriers in the crystalline semiconductor, the higher the amplitude of the pulse diffusion current and power terahertz radiation. Thus, the main power terahertz radiation is formed by the areas around thick edges of a metal strip. The coated strips similar way to form co-directed vectors of gradients of concentration of photoexcited carriers when illuminated by laser radiation of the whole structure. Thus, the amplitude of the terahertz waves emitted from each region near the thick edges of a metal strip, which is essentially elementary emitter stack.
A disadvantage of the known technical solution is inefficient use of femtosecond laser radiation, which covers the entire surface of the elementary emitter, including areas that are not involved in the generation of terahertz radiation: the entire surface of the metal strip and the area near its thin edges. The total area of the regions not involved in the generation of terahertz radiation, more of the total area involved. An additional disadvantage of the data is th technical solution is to generate a divergent beam of terahertz radiation, that requires the use of large sample size for spectroscopic studies and reduces the energy density of terahertz radiation are required, for example, for biological research.
The authors task was to develop a multi-element generator of terahertz radiation based on conversion of femtosecond laser radiation, with more efficient use of laser radiation.
The problem is solved in that the multi-element generator of terahertz radiation, containing the sample, the laser emitting femtosecond laser radiation, multiple emitter comprising at least one elementary emitter, which is a layer of crystalline semiconductor with sprayed metal mask, forming a sharp gradient light layer of crystalline semiconductor femtosecond laser radiation, on the border of the lit and unlit portions of a layer of crystalline semiconductor formed a sharp concentration gradient of the photoexcited charge carriers parallel to the surface of the crystalline semiconductor layer, further comprises an elliptical mirror, made forming a focused beam of terahertz radiation and containing an opening for passing pentose odnogo laser radiation, and multiple emitter is made containing raster cylindrical microlenses, distributing femtosecond laser radiation between elementary emitters and forming on the layer of crystalline semiconductor light only the areas involved in the generation of terahertz radiation, in addition, a metal mask in the form of flat metal strips, and the crystalline semiconductor layer is made in the form of a crystal of InAs at a wavelength of femtosecond laser radiation 775 nm and at a wavelength of femtosecond laser 1550 nm layer of crystalline semiconductor is made in the form of crystal InSb
The technical effect of the claimed device is to increase the conversion of femtosecond laser radiation in the terahertz radiation; the increase in energy density is focused on the sample terahertz radiation, and the ability to use samples of small size and expanding the range of devices for this purpose.
Figure 1 presents a block diagram explaining the operation of the inventive multi-element generator of terahertz radiation, where 1 - laser, 2 - femtosecond laser radiation, 3 - hole, 4 - multiple emitter, 5 - terahertz radiation, 6 - elliptical mirror, 7 - ASCS is adremy sample.
Figure 2 presents a diagram explaining the operation of the multichannel emitter, where 2 - femtosecond laser radiation, 5 - terahertz radiation, 8 - raster cylindrical microlenses, 9 - elementary emitter, 10 - metal mask 11 - crystalline semiconductor 12 - fotovozbuzhdenie charge carriers, 13 - vector of the gradient of the concentration of photoexcited charge carriers.
The inventive multi-element generator of terahertz radiation works in the following way. The laser 1 generates femtosecond laser radiation 2 at the wavelength of the femtosecond laser 1550 nm or 775 nm. Femtosecond laser radiation 2 is directed through the opening 3 in the elliptical mirror 6 on multiple emitter 4, the radiation area which is located in one of the two foci of the elliptical mirror 6 and which converts femtosecond laser radiation 2 in the terahertz radiation 5. Terahertz radiation 5 is converted elliptical mirror 6 in a focused beam of high energy density concentrated in the region of the second focus of the elliptical mirror 6, where the sample 7, therefore, is one of the technical effects of the invention, allowing to use to study samples of small size.
In multielement emitter proishodit conversion of femtosecond laser radiation 2 in the terahertz radiation 5 as follows. Multiple emitter 4 comprises at least one elementary emitter 9. Femtosecond laser radiation 2 is evenly distributed pattern of cylindrical microlenses 8 between elementary emitters 9 and focuses on the crystalline semiconductor layer 11 in the region involved in the generation of terahertz radiation, namely at the edge of the metal mask 10, in the form of flat metal strips deposited on the crystalline semiconductor layer 11. The metal mask 10 should have sufficient thickness so as not to miss femtosecond laser radiation 2. Periods strips of the metal mask 10 and raster cylindrical microlenses 8 should be the same. The width of the stripes of the metal mask 10 and the distance between the bars should not be less than half the width of the intensity distribution of femtosecond laser radiation 2 in focus raster cylindrical microlenses 8. The lateral dimensions of the metal mask 10 and the region of the crystalline semiconductor 11 covered elementary emitters 9, shall be not less than the transverse dimensions of femtosecond laser radiation 2. The thickness of the crystalline semiconductor layer 11 must be at least 4/α (where α is the absorption coefficient of the crystalline semiconductor) to ensure absorption of not less than 98% of the femtosecond laser and the radiation 2, held inside this layer.
The edges of the metal mask 10 is displaced relative to the center of focus of the corresponding microlens raster cylindrical microlenses 8 by a distance not greater than the diameter of the light spot focused femtosecond laser radiation 2, so that the surface of the crystalline semiconductor 11, which may be in the form of a crystal of InAs at a wavelength of femtosecond laser radiation 775 nm or InSb crystal at a wavelength of femtosecond laser 1550 nm, near the end of the metal mask 10 is formed a sharp gradient illumination of femtosecond laser radiation 2. The gradient of the light absorption of femtosecond laser radiation 2 in the crystalline semiconductor 11 leads to the formation of a maximally sharp density gradient of the photoexcited charge carriers 12, and the proportion of intensity of a beam of laser radiation reflected from the metal mask 10, minimum. The vector gradient of the concentration of photoexcited charge carriers 13 collinear with the vector of the pulse current generated in accordance with the effect of Dember and leading to the generation of terahertz radiation 5 which is emitted perpendicular to the gradient vector of the concentration of photoexcited charge carriers 13 and accordingly the surface of kristallicheskogo semiconductor 11 in the direction opposite to the direction of propagation of femtosecond laser radiation 2. Since the vectors of gradients of concentration of photoexcited charge carriers 13 each elementary emitter 9 directed vectors of terahertz radiation 5 is also collinear, and their amplitudes are added together, forming a common beam.
Thus, by reducing losses femtosecond laser radiation 2 in the reflection from the metal mask 10 and increase its absorption in the crystalline semiconductor 11 increases the conversion of femtosecond laser radiation 2 in the terahertz radiation 5 and achieves the technical effect of the claimed invention.
The advantage of the inventive multi-element generator of terahertz radiation is also the possibility of using metal masks with simple profile shape of the bands allows to simplify the manufacture of the generator and to reduce its cost.
1. Multi-element generator of terahertz radiation, containing the sample, the laser emitting femtosecond laser radiation, multiple emitter comprising at least one elementary emitter, which is a layer of crystalline semiconductor with sprayed metal mask, forming a sharp gradient light layer of crystalline floor is Roudnice femtosecond laser radiation, at the border of the lit and unlit portions of a layer of crystalline semiconductor formed a sharp concentration gradient of the photoexcited charge carriers parallel to the surface of the crystalline semiconductor layer, characterized in that it further comprises an elliptical mirror, made forming a focused beam of terahertz radiation and containing an aperture for transmission of femtosecond laser radiation, and multiple emitter is made containing raster cylindrical microlenses, distributing femtosecond laser radiation between elementary emitters and forming on the layer of crystalline semiconductor light only the areas involved in the generation of terahertz radiation, in addition, a metal mask in the form of flat metal strips.
2. Multi-element generator of terahertz radiation according to claim 1, characterized in that the crystalline semiconductor layer is made in the form of a crystal of InAs at the wavelength femtosecond laser radiation 775 nm.
3. Multi-element generator of terahertz radiation according to claim 1, characterized in that the crystalline semiconductor layer is made in the form of InSb crystal at a wavelength of femtosecond laser 1550 nm.
SUBSTANCE: passive optical shutter has a reflecting metal film on a substrate, placed in the intermediate real image plane of the optical system of a radiation detector. The film has an underlayer of a thermal decomposing chemical compound with emission of gases.
EFFECT: high shutter speed, low radiation intensity threshold of actuation of the shutter.
3 cl, 5 dwg
FIELD: technological processes.
SUBSTANCE: invention relates to lighting engineering. The illumination system comprises a light-emitting part (1), having light sources configured to emit light beams at different dominant wavelengths, and an image-forming optical system (3), having microlenses (3a) configured to focus the light beams emitted by the light-emitting part (1). The illumination system is configured to illuminate a liquid crystal panel with light beams passing through the image-forming optical system (3). The liquid crystal panel has pixels which are spaced apart by a predetermined spacing and each of which has display elements corresponding to each separate colour, and under the condition that the spacing of the pixels is denoted by P, and the image-forming optical system has a zoom factor (1/n), the light sources are spaced apart by a spacing P1, given as P1=n × P, and the microlenses are spaced apart by a spacing P2, given as P2=(n/(n+1)) × P.
EFFECT: high quality of display by suppressing non-uniformity of brightness and colour in the display screen.
32 cl, 16 dwg
FIELD: physics, optics.
SUBSTANCE: invention relates to optical engineering. The apparatus for modulating monochromatic optical radiation comprises an optically transparent medium in which are mounted a splitter for splitting monochromatic optical radiation into a first and a second propagation channel, a reflecting element in the second channel, a coherent summation portion for forming modulated monochromatic optical radiation. The splitter used for splitting monochromatic optical radiation into a first channel and a second channel is a splitting cube consisting of two identical triangular prisms joined by their large faces. The first channel is equipped with its own reflecting element. Each reflecting element is deposited on the corresponding face of the splitting cube on the path of the monochromatic optical radiation in the first and second channels. The splitting cube is mounted such that it can move back and forth outside the interface plane of its prisms, and the angle α between the velocity vector of the back and forth movement and the interface plane of the prisms of the splitting cube is selected from the relationship , where fm is the required modulation frequency of the monochromatic optical radiation, λ0 is the wavelength of monochromatic optical radiation at the input of the splitting cube, υ is the velocity of the splitting cube.
EFFECT: resistance to vibrations and pushing, capacity to operate in all spatial orientations.
SUBSTANCE: invention relates to the field of lighting equipment. A highlighting unit 12 consists of a LED 17, a chassis 14 including a base plate 14a mounted at the side opposite to the side of the light output in regard to the LED 17, at that the chassis 14 contains the LED 17 and the first reflective sheet 22 that reflects light. The first reflective sheet 22 includes a four-sided base 24 running along the base plate 14a and two elevated portions 25 and 26, each of these portions is elevated from each of two adjacent sides of the base 24 in direction of the light output. There is a junction J between two adjacent side edges 25a and 26b of the elevated portions 25 and 26. In the highlighting unit 12 the side edge 25a of the first elevated portion 25 out of the two elevated portions 25 and 26 has a face piece 28 faced to the side edge 26a of the elevated portion 26 in the same direction in which the first elevated part 25 is elevated from the base 24 outside towards axis Y, and the first elevated part 25 and the face piece 28 are extruded towards direction of the light output.
EFFECT: elimination of uneven brightness.
22 cl, 29 dwg
SUBSTANCE: display device contains ambient light system (100) to emit ambient light (106) to the wall (107) behind display device (104). Ambient light system includes at least one source (101) of light located in the central part of display device (104) rear side and at least one reflector (102) located at display device (104) rear side. At least one reflector (102) is located at the periphery of display device (104) rear side so that when display device (104) is located close to the wall (107) the light emitted by at least one source of light is reflected by reflector (102) towards the wall (107) in such way that reflected light (106) at least partially encloses the observed area of display device (104) at the periphery.
EFFECT: improving efficiency.
13 cl, 7 dwg
SUBSTANCE: invention relates to the field of lighting equipment. Lighting device (12) is equipped with a number of optical source cards (20) with variety of point optical sources (17) installed at them. Average colour tone of point optical sources (17) (POS) at each card (20) is in equivalent colour range defined by the square, and each opposite side of two square sides has coordinate length in the axis X equal to 0.015, and each opposite side of two square sides has coordinate length in the axis Y equal to 0.015 at the colour space chromaticity chart of International Commission on Illumination as of 1931. POS are categorized into three colour ranges defined by squares, at that each side of the square has a length of 0.015. At that the second and third ranges adjoin the first one that includes the above equivalent colour range. POS cards include the first cards with installed point optical sources in the first and second colour ranges, and the second cards with installed point optical sources in the first and third colour ranges. The first and second POS cards are placed in sequence.
EFFECT: providing total emission of practically uniform colour.
26 cl, 17 dwg
SUBSTANCE: invention relates to imaging terahertz (THz) radiation (ν=0.1-10 THz or λ=30-3000 mcm) and can be used to design devices for detecting and analysing terahertz radiation. The device for imaging terahertz radiation sources has a converter for converting terahertz radiation to infrared radiation, which consists of a layer of artificial metamaterial with resonant absorption of terahertz radiation, deposited on a solid-state substrate made of sapphire, placed between an input terahertz lens and an infrared camera lens situated on the side of the substrate. The converter is based on a gelatin matrix which contains metal nanoparticles and is provided with a cut-off filter placed in front of the matrix to allow filtration of thermal radiation of the terahertz radiation source with wavelength of not more than 30 mcm.
EFFECT: high noise-immunity of the design, low noise level and high sensitivity while simplifying the design of the imaging device.
16 cl, 6 dwg
SUBSTANCE: backlighting device (20) comprises a substrate (22), where multiple point sources of light are placed in the form of light diodes (21), and slots (23), which are also arranged on the substrate. Multiple point sources of light include the first point source of light (21), which is placed near the slot (23), and the second point source of light (21), which is placed in a position distant from the slot (23) compared to the first point source of light (21). The light beam in the surroundings of the slots is higher than the light beam in the area different from the surroundings of the slots.
EFFECT: reduced heterogeneity of brightness of a display panel without increase in number of process operations.
15 cl, 12 dwg
FIELD: physics, optics.
SUBSTANCE: backlight for a colour liquid crystal display includes white light LEDs formed using a blue LED with a layer of red and green phosphors over it. In order to achieve a uniform blue colour component across the surface of a liquid crystal display screen and achieve uniform light output from one liquid crystal display to another, the leakage of blue light of the phosphor layer is tailored to the dominant or peak wavelength of the blue LED chip. The backlight employs blue LED chips having different dominant or peak radiation wavelength.
EFFECT: different leakage amounts of light through the tailored phosphor layers offset the attenuation on wavelength of the liquid crystal layers.
15 cl, 13 dwg
SUBSTANCE: liquid crystal display device (100) of the present invention includes a liquid crystal display panel (10) and a lateral illumination unit (20) which emits light from a position which is lateral with respect to the panel (10). The panel (10) includes a front substrate (1), a back substrate (2) and a light-diffusing liquid crystal layer (3). The unit (20) includes a light source (7), which is situated in a position which is lateral with respect to the panel (10), and a light-guide (6), having a light-output surface (6b) through which light emitted by the light source (7) as well as light incident on the light-guide (6) is emitted towards the end surface (1a) of the substrate (1). The surface (6b) is slanted relative a direction which is vertical with respect to the front surface (1b) of the substrate (1), such that it faces the back surface of the panel (10).
EFFECT: preventing generation of a bright line in the panel.
3 cl, 6 dwg
FIELD: mechanical engineering.
SUBSTANCE: device has signal form generator, power amplifier and electromechanical block, including first fixed magnetic system and first coil of current-conductive wire, additionally included are integrator and corrector of amplitude-frequency characteristic of electromechanical block, and block also has second fixed magnetic system and second coil of current-conducting wire, rigidly and coaxially connected to first coil. Connection of first and second coils with fixed base is made in form of soft suspension with possible movement of first and second coils, forming a moving part of modulator, relatively to fixed magnetic systems, while output of said signal shape generator is connected to direct input of integrator, inverse input of which is connected to speed sensor of moving portion of modulator, output of integrator is connected to input of corrector, to output of which input of said power amplifier is connected.
EFFECT: higher precision.
3 cl, 8 dwg
FIELD: conversion of optical radiation by using nanotechnology.
SUBSTANCE: transparent nano-particles having volume of 10-15 cm3 are illuminated by white light. Nano-particles are activated by impurity atom with concentration of 1020-1021cm-3 and are strengthened in form of monolayer onto transparent substrate. Nano-particles are made of glass and are glued to substrate by means of optically transparent glue. Substrate can be made flexible.
EFFECT: high brightness of image.
4 cl, 1 dwg
FIELD: optical instrument engineering.
SUBSTANCE: modulator has non-monochromatic radiation source, polarizer, first crystal, first analyzer, and second crystal, second analyzer which units are connected together in series by optical coupling. Modulator also has control electric field generator connected with second crystal. Optical axes of first and second crystals are perpendicular to direction of radiation and are parallel to each other. Axes of transmission of polarizer and analyzers are parallel to each other and are disposed at angle of 45o to optical axes of crystals.
EFFECT: widened spectral range.
FIELD: engineering of displays.
SUBSTANCE: to decrease number of external outputs of screen in liquid-crystalline display, containing two dielectric plates with transparent current-guiding electrodes applied on them, each electrode of one plate is connected to selected electrode of another plate by electric-conductive contact, while each pair of electrodes is let out onto controlling contact zone, and electrodes, forming image elements of information field of screen, on each plate are positioned at angle φ similar relatively to external sides of plates, while angle φ satisfies following condition: 10°≤φ≤85°.
EFFECT: decreased constructive requirements for display.
4 cl, 4 dwg, 1 tbl
FIELD: optical engineering.
SUBSTANCE: device has optically connected single-frequency continuous effect laser, photometric wedge, electro-optical polarization light modulator, first inclined semi-transparent reflector, second inclined semi-transparent reflector and heterodyne photo-receiving device, and also second inclined reflector in optical branch of heterodyne channel, high-frequency generator, connected electrically to electro-optical polarization modulator, direct current source, connected to electrodes of two-electrode vessel with anisotropic substance, and spectrum analyzer, connected to output of heterodyne photo-receiving device.
EFFECT: possible detection of "red shift" resonance effect of electromagnetic waves in anisotropic environments.
FIELD: electro-optical engineering.
SUBSTANCE: fiber-optic sensor system can be used in physical value fiber-optic converters providing interference reading out of measured signal. Fiber-optic sensor system has optical radiation laser detector, interferometer sensor, fiber-optic splitter, photodetector and electric signal amplifier. Interferometer sensor is equipped with sensitive membrane. Fiber-optic splitter is made of single-mode optical fibers. Connection between fiber-optic splitter and interferometer sensor is based upon the following calculation: l=0,125λn±0,075λ, where l is distance from edge of optical fiber of second input of fiber-optic splitter to light-reflecting surface of sensor's membrane (mcm); λ is optical radiation wavelength, mcm; n is odd number within [1001-3001] interval.
EFFECT: simplified design; compactness; widened sensitivity frequency range.
4 cl, 1 tbl, 3 dwg
SUBSTANCE: method can be used in optical filter constructions intended for processing of optical radiation under conditions of slow or single-time changes in processed signal, which changes are caused by non-controlled influence of environment. Optical signal is applied to entrance face of photo-refractive crystal where phase diffraction grating is formed by means of use of photo-refractive effect. Reflecting-type phase diffraction grating is formed. For the purpose the optical signal with duration to exceed characteristic time of phase diffraction grating formation, is applied close to normal line through entrance face of photo-refractive crystal of (100) or (111) cut onto its output face which is formed at angle of 10°to entrance face. Part of entrance signal, reflected by phase diffraction grating, is used as output signal. To apply optical signal to entrance face of photo-refractive crystal, it has to be transformed into quazi-flat wave which wave is later linearly polarized.
EFFECT: power independence of processing of optical signal.
2 cl, 2 dwg
FIELD: measuring equipment.
SUBSTANCE: optical heat transformer includes base of body with optical unit positioned therein, transformer of heat flow and consumer of heat flow in form of thermal carrier. Optical unit consists of optical heat source and reflectors of coherent heat flows and concentrator - generator of coherent heat flow in form of two collecting mirrors and a lens, positioned on different sides of source, with possible redirection of coherent heat flow for interaction with transformer of heat flow with following transfer of heat flow.
EFFECT: decreased energy costs.
FIELD: measuring technique.
SUBSTANCE: electro chromic device has first substrate, which has at least one polymer surface, ground primer coat onto polymer surface, first electro-conducting transparent coating onto ground primer coat. Ground primer coat engages first electro-conducting coating with polymer surface of first substrate. Device also has second substrate disposed at some distance from first substrate to form chamber between them. It has as well the second electro-conducting transparent coating onto surface of second substrate applied in such a way that first coating is disposed in opposition to second one. At least one of two substrates has to be transparent. Device also has electrochromic medium disposed in chamber, being capable of having reduced coefficient of light transmission after electric energy is applied to conducting coatings. Electrochromic medium and ground primer coat are compatible.
EFFECT: simplified process of manufacture; cracking resistance.
44 cl, 1 dwg
FIELD: laser and fiber optics.
SUBSTANCE: in accordance to invention, optical wave guide is heated up during recording of Bragg grating up to temperature, which depends on material of optical wave guide, and which is selected to be at least 100°C, but not more than temperature of softening of optical wave guide material, and selected temperature is maintained during time required for recording the Bragg grating.
EFFECT: increased thermal stability of recorded Bragg gratings.
2 cl, 3 dwg