(57) Abstract:Usage: in an optical instrument for enlightenment parts. The inventive antireflective coating consists of alternating layers, the first and third of which are made with high refractive index, and the second and fourth low refractive index and optical thickness of the layers counting from the substrate, is treated as 10 : 6 : 4 : 1, and adjacent to the substrate layer has an optical thickness 0,163oin this case nin= 2,28 - 2,39; nn= 1,35 - 1,51;o= 10600 mm 1 Il. The invention relates to the technology of optical coatings and can be used in an optical instrument for enlightenment parts.Known ar coating  consisting of five layers of alternating high and low refractive indices, the optical thickness of which is connected by the relation 1,78:0,25:0,23:1,08:0,92, and adjacent to the substrate layer has an optical thickness 0,4450where0the wavelength corresponding to the middle of the range enlightenment.The closest technical solution to offer is the ar coating for optical elements  consisting of four dielectric, W is C substance with a high refractive index, and optical thickness connected by the relation
2nind12nnd22nind3nind40,250< / BR>However, the known coating can only be used for optical elements made from a material with a refractive index of 1.45 to 1.8.Object of the invention is robust and resistant to laser radiation antireflection coating, providing the transmission of 95-97% in the spectral range of 8-12 μm, for optical elements with refractive index of 2.2 and 2.7.The problem is solved due to the fact that in the antireflection coating consisting of alternating layers, the first and third of which are made with high ninrefractive index, and the second and fourth low-nnthe refractive index. The optical thickness of the layers counting from the substrate, is treated as 10:6:4:1, and adjacent to the substrate layer has an optical thickness 0,163 0while nin2,28-2,39; nn1,35--1,51;0= 10600 nm.Set out the essential features, namely, the optical thickness of the layers linked by a ratio of 10:6:4:1 and adjacent to the substrate layer, equal 0,163 0provide the coating with a total thickness of 0,3420optical is jku each component of the coating is divided into thinner layers, and its total thickness is slightly more than a quarter wavelength, which significantly reduces the stresses in the layers of coating.The drawing shows a spectral transmittance curve measured on the X-29.From the above specifications you can see that the ar coating effectively reduces reflected in a wide spectral range for optical elements used in optical instruments, in particular, thermal imaging devices.The proposed floor has the "0" group strength abrasion.The coating is applied by thermal or electron beam evaporation in a vacuum ion-beam-assist vacuum installing WU-1A.Make details of the optical materials: zinc sulphide, zinc selenide, cadmium telluride. For applying a layer with a high refractive index of ninuse zinc sulphide, and for applying a layer of low refractive index fluoride of yttrium.The average transmittance enlightened optical components 10 mm thickness in range (0,8-1,2)104nm, measured on the X-29, shown in the table.The table shows that the value of bandwidth is 95-97%
inrefractive index, and the second and fourth low-nnrefractive index, characterized in that the optical thickness of the layers counting from the substrate, is treated as 10 : 6 : 4 : 1, and adjacent to the substrate layer has an optical thickness 0,163 owhile nin= 2,28 - 2,39; nn= 1,35 - 1,51;o= 10600 nm.
FIELD: optical engineering.
SUBSTANCE: at least two dielectric layers are produced with preset thickness. Layers are disposed one onto the other to form pack of layers. Thickness of layer packs is subject to reduction and thicknesses of separate layers are similarly reduced by means of deforming layer packs to keep relation of thicknesses or relation of thicknesses of layers. Layer pack is disposed between two carrying layers before subjecting the layers to deformation. At least one carrying layer is formed from several separate layers, which are supposed to be disposed subsequently at the end of process of partial deformation at any previous layer of carrying layer. Separate layers of carrying layer can be overlayed onto previous separate layers of carrying layer.
EFFECT: simplified process of manufacture; improved reflection factor.
FIELD: optical instrument engineering.
SUBSTANCE: invention can be used for wide-band light reflecting. Reflecting surface has dielectric layers A, B and C. A layer is made of material having low refractivity, B layer is made of material with average refractivity and C layer is made of material having high reflectivity. Optical thickness of layers equals to λr/4, where λr is wavelength of middle part of interval having high refractivity. Sequence of layer alternation looks like (CDCABA)KCBC, where K>=and has to be integer. Spectrum range with high reflectivity is widened due to shift in adjacent bandwidths at opposite sides along wavelength scale.
EFFECT: widened spectrum range with higher refractivity.
FIELD: optical engineering.
SUBSTANCE: device can be used for getting image from space, including surface of Earth, from space and from different sorts of air carriers. Device has at least one information channel which channel has objective, filter and multi-element receiver. Filter is made of two lenses, which lenses form flat-parallel plate. Lenses are made of the same material with equal radiuses of curvature of their spherical surfaces. Interference coatings are applied onto spherical surfaces, which coatings form, together with material of lenses, spectral range of device. Filter can be installed between objective and radiation receiver. In this case the first lens is made flat convex, the second one is flat concave. Center of radius of curvature of spherical surface of flat-convex lens is brought into coincidence with center of exit pupil of objective. Filter can be installed in front of objective.
EFFECT: constancy of borders of spectral sensitivity and of level of transmission within total area of angle of view; improved precision of measurement.
7 cl, 3 dwg
FIELD: optical instrument engineering.
SUBSTANCE: optical filtering device can be used for building devices for spectral filtration of optical images, for example, for wavelength re-tune optical filters, IR imagers working within specified narrow spectral ranges. Filtering device being capable of re-tuning within preset wavelength range is based upon interferometers. Interferometers are disposed along path of filtered radiation flow at different angles to axis of flow. Reflecting surfaces of plates of any interferometer, which plates are turned to meet one another, are optically polished and they don't have metal or interference mirror coatings. To filter selected wavelength of λm; the following distances among reflecting faces of interferometers: d1=(λm/2)k, k=1 or k=2, dn=(n-1)d1 or nd1. Filtering device is equipped with different filters which cutoff radiation outside borders of range to be filtered, including filters which are made of optical materials being transparent within band of spectral characteristic of sensitivity of consumer's receiver, which receiver registers filtered radiation. Filter cutting off short wavelength radiation is made of materials, which form border with positive derivative of dependence total internal reflection angle depending on wavelength. Filter cutting off long wavelength radiation is made of materials which form border with negative derivative of angle of total internal reflection depending on wavelength.
EFFECT: improved stability of parameters; increased transmission ability in maximal points of bands and reduction in number of transmission bands; increased relative aperture; higher quality of filtration; reduced number of side maximums.
4 cl, 5 dwg
FIELD: narrowband filtration covers.
SUBSTANCE: narrowband filtration cover contains two systems of alternating dielectric layers with different refraction coefficients and equal optical thickness λ0/4, in the form of high reflection mirrors, and a dielectric layer dividing them. In accordance to the invention, structure of high reflection mirrors additionally features dielectric layers with intermediate value of refraction coefficient and dividing layer has optical thickness λ0 or one divisible by it, and sequence of layer alternation has form (CBCABA)KD(ABACBC)K with nA<nB<nC, where refraction coefficient of dividing layer nD is not equal to nA (for example, nD=nC) and k≥1 is an integer number, where: λ0 - maximal filtration cover throughput wave length; A, B and C - dielectric layers with values of refraction coefficient nA, nB and nC respectively, and D - dividing layer.
EFFECT: increased selectivity due to expansion of high reflection bands on the sides of pass band.
FIELD: fiber-optic transmission systems.
SUBSTANCE: optical multilayer filter has N dielectric layers made of materials with different refractivity. Optical thickness of any layer equals to λ/4, where λ average wavelength of transmission band of optical filter. Optical multilayer filter is composed of input optical transformer, selective part and output optical transformer. Level of signal distortions is reduced till preset value for wide range of frequency characteristics of decay of filter within preset transmission band and decay is improved within delay band till preset value.
EFFECT: widened area of application.
FIELD: fibre-optic communication, optical multilayer filters.
SUBSTANCE: optical multilayer filter (OMLF) consists of an input optical transformer (In. OT 1), a selective part (SP 2), and output optical transformer (Out. OT 3) and substrates 5, 6. The In. OT 1, SP 2, and Out. OT 3 consist of NIn=2s, Nsp=4k and Nout=2r alternating layers 7 and 8, respectively, with high nh and low nl values of refractive indices of materials they are made of. The thickness of every layer d=0.25λ, where λ is the mean OMFL bandwidth wave length. Refractive indices of adjoining layers of the In OT and SP, and those of SP and Out.OT are equal. Note that the SP alternating layers are made from materials with refractive indices mirror-symmetric relative to the SP centre. The first layer of In. OT and the last layer of Out. OT are connected to substrates. Proposed are the relations to calculate the parameters of claimed arbitrary type OMLF.
EFFECT: reduction of signal distortion to preset magnitude in a wide frequency range of the filter attenuation in the preset bandwidth and increase in attenuation to the preset magnitude that allows wider application of the aforesaid filters.
3 cl, 7 dwg
SUBSTANCE: invention concerns area of optical thin-film coatings. The spectral divider contains the optical interference system with alternating quarter wave layers; part of them has an optical thickness not multiple to quarter of length of an emission wave. The spectral divider design allows obtaining the optimised spectral characteristics having small fluctuations of the transmittance factor in a working range of transparency.
EFFECT: spectral divider can be used at a direct and inclined light ray tilt angle in various geodetic devices and special purpose devices.
2 cl, 4 dwg
FIELD: physics, optics.
SUBSTANCE: tunable optical filter with Fabry-Perot interferometre has transparent plates with mirror coatings with spacing in between. When making the said optical filter, a sacrificial layer is deposited on one plate with the mirror coating. A mirror coating is then deposited on top and the second transparent plate is attached through a layer of hardening material. After that the said plates are attached to holders through a hardening material and the sacrificial layer is removed through evaporation by heating to temperature below the thermal destruction temperature of the hardening layer.
EFFECT: easier obtaining of controlled spacing between plates, avoiding use of special methods of obtaining surfaces with high degree of flatness, avoiding the need to monitor the value of the spacing and its wedge.
SUBSTANCE: fibro-optical connector comprises first and second half-couplings to receive first and second sections of optical fiber. First and second pairs of step-down optical multilayer transformers are arranged on end faces of said sections. Air gap is arranged between outer layers of said first and second pairs of said transformers. Layers of first and second pairs of aforesaid transformers are made from materials with differing indices of reflection and are counted from outer layers of aforesaid transformers in direction of the end faces of connected sections of optical fiber. Thickness of every layer makes one fourth of average signal wave λ0 transmitted over optical fiber, while the number of layers is selected subject to conditions covered by invention claim.
EFFECT: reduced power loss, expanded performances.
4 cl, 9 dwg