Method and device for focusing laser radiation
FIELD: optical instrument engineering.
SUBSTANCE: before conversing parallel laser radiation beam of continuous cross-section to circular-section beam, the central round-shaped part is cut out of parallel laser radiation beam for subsequent delivery to specified circular-section beam convergence point. Device has entrance and exit axions that are optically conjugated. One reflecting conic surface of axion is mounted onto ends of hollow rod connected with other reflecting conic surface of axions through pylons. Cavity of rod is divided by partition provided with nozzles for supplying coolant into mentioned compartments. Reflecting surfaces of axions and partition of rod are made with through axial holes. Diameter of axial hole of reflecting conic surface of axions is commensurable with diameter of spot of focused laser radiation. Laser radiation beams can be focused with higher power of density.
EFFECT: increased power density.
4 cl, 1 dwg
The invention relates to the field of laser technology and can be used in the delivery of the focused laser beam on the object (for example, when creating a laser technological complexes).
Known methods focusing of a laser beam, based on the transformation of the parallel light beam in a beam of annular cross-section with its subsequent note to the specified point.
Device for the implementation of the methods is made on the basis of optically conjugate Aksyonov, see L.W.Casperson and M.S.Shekhani. Breakdown in a Radial-Mode Focusing Element. Appl. Opt., v.13, No. 1, 1974, p.p.104-108 and W.R.Edmonds. The Reflakxicon, a New Reflective Optical Element, and Some Applications. Appl. Opt, v.l2, No. 8, 1973, p.p.1940-1945.
The closest technical solution(prototype) of the present invention is a method of focusing of a laser beam, comprising converting a parallel beam of laser radiation solid section in a beam of annular cross-section for further information in the set point, see U.S. Pat. Of the Russian Federation No. 2240615 (application No. 2003110805/06 16. 04.2003,), IPC G 21 K 1/00.
The device for implementing the above method comprises optically coupled input and output axicon made in the form of inner and outer rotation bodies each, while the inner body rotation Aksyonov mounted on the ends of the hollow rod associated with the outer rotation bodies of Aksyonov through the pylons, and the floor is the motion of the rod is divided into two compartments by transverse partition with nozzles for supplying refrigerant in said compartments.
The shortcoming of the above technical solution is reduced power density at the focused beam of laser radiation due to the presence of the tip (point of contact) on the inner body rotation of the input axicon, leading to overheating of the latter (due to the difficulty of heat removal at high levels of power density of the focused radiation and, consequently, to progressive destruction of the inner body input axicon from its apex to the periphery (to avoid the above-mentioned negative phenomena the top of the inner body input axicon need to dull flat transverse faces, which leads to the decrease of energy in the focal spot and reduces the upper limit of the level of power density of the focused laser radiation).
The technical result from the use of the proposed technical solution is to increase the power density of the focused beam of laser radiation.
In accordance with the invention the above technical result is achieved in that in the method of focusing of a laser beam, comprising converting a parallel beam of laser radiation solid section in a beam of annular cross-section for further information in the set point, before converting the parallel beam of the laser is about radiation solid section in a beam of annular cross-section, from a parallel beam of laser radiation solid section cut out of the Central part of the circular cross-section for its subsequent submission to the target point information of a beam of annular cross-section.
A device for focusing of a laser beam containing optically coupled input and output axicon made in the form of inner and outer rotation bodies each, while the inner body rotation Aksyonov mounted on the ends of the hollow rod associated with the outer rotation bodies of Aksyonov through the pylons, and the cavity of the rod is divided into two compartments by transverse partition with nozzles for supplying refrigerant in said compartments, the inner body rotation Aksyonov and the wall of the rod is made with a through axial holes, the hole diameter of the inner body rotation of the input axicon is comparable with the spot diameter of the focused laser beam and the axial holes of the partitions of the rod and internal rotation bodies of Aksyonov isolated from the compartments of the hollow rod sealed elements.
In addition, the sealed hollow elements made in the form of thin-walled tubes mounted coaxially aligned axial bores in the inner rotating bodies of Aksyonov and stud partitions.
In addition, the internal diameter thin-walled tubes, the diameters of the holes of the partition rod the inner body rotation of the output axicon equal to or greater than the diameter of the hole of the inner body rotation of the input axicon.
The drawing shows a device for realization of the proposed method.
The device comprises optically coupled input and output axicon made in the form of a conical external 1, 2, and 3 internal, 4 rotating bodies. The inner body of rotation 3, 4 Aksyonov mounted on the ends of the podyjí rod 5 that is associated with the outer rotation bodies 1, 2 Aksyonov through pylons 6 and the housing 7. The cavity of the rod 5 is divided by transverse partition 8 into two compartments 9, 10, which serves a refrigerant for cooling the internal bodies Aksyonov) through the channels 11, 12 through nozzles 13, 14 provided on the partition wall 8. The output of the refrigerant through the channels 15, 16 (input and output channels for the refrigerant structurally, it is advisable to perform inside the pylons 6).
On the inner rotary bodies 3, 4 Aksyonov device has axial holes 17, 18 and the partition wall 8 of the rod 5 is provided an axial channel (hole) 19, the latter being tightly connected by means of a thin-walled tubes 20, 21 with the holes 17, 18 of the inner rotary bodies 3, 4 Aksyonov. The diameter d of the internal body rotation - 3 input axicon made commensurate with the spot diameter of the focused beam of laser radiation (preferably equal to the effective diameter of the spot of the focused laser beam at the point F).
For the free passage of the Central part (area) of the beam of laser radiation internal diameters of the tubes 20, 21, the diameter of the channel 19 of the partition 8 of the rod 5 and the inner diameter of the hole of the body of rotation 4 of the output of the axicon is made equal to or larger than the diameter d of the axial bore of the inner body rotation 3 input axicon.
Implementation of the proposed method using the device is as follows.
Parallel I beam of laser radiation of a solid circular cross-section and serves on the inner body rotation 3 (with a conical reflecting surface) of the input axicon, which after reflection from the surface of the latter with the aid of outer body rotation 1 input axicon is converted into the beam II ring sections for submission to the external body of rotation 2 of the output of the axicon. After reflection from the outer surface of the body of revolution 2 beam II carried out his information in the set point F through the inner body of rotation 4 of the output of the axicon (point F is placed in the focal plane of the device and has an effective diameter of the focused spot (reduced) radiation, equal to d). When applying radiation to the inner body of rotation 3 of the input of the axicon beam I cut out (produce) in its Central part (area) III with diameter d in the cross section through the axial bore 17 of the body 3 (the diameter of the hole 17 is chosen from the condition of commensurability with the diameter of the focused spot (reduced) is zlecenia beam II).
Cut from the beam I part III radiation is passed through the tube 20, the channel 19, the tube 21 and serves to point F of the information beam II to summarize from the last.
The heat from the internal bodies 3, 4 Aksyonov carried out by pumping refrigerant (coolant) through the compartments 9, 10 through the inlet 11, 12 and output 15, 16 channels of the hydraulic system (in graphical materials conventionally not shown).
From the above it follows that the proposed solution has the advantage compared with the known, namely:
- due to the full utilization of the energy of the light beam (including its Central part) increases the power density in the focal spot is reduced at a given point of emission;
the absence of sharp peaks on the inner body input axicon reduces the degree of heating of the body and improves the heat sink, which allows the focusing of a beam of laser radiation with high power density.
Therefore, when using the invention gives the technical result consists in the possibility of using laser beams with high power density of light energy.
1. The method of focusing of a laser beam, comprising converting a parallel beam of laser radiation solid section in a beam of annular cross section for posleduyushego the information in the set point, characterized in that before converting parallel beam of laser radiation solid section in a beam of circular cross-section, of a parallel beam of laser radiation solid section cut out of the Central part of the circular cross-section for its subsequent submission to the target point information of a beam of annular cross-section.
2. A device for focusing of a laser beam containing optically coupled input and output axicon made in the form of two conical reflecting surfaces each, with one reflecting conical surface Aksyonov mounted on the ends of the hollow rod associated with the other conical reflecting surface Aksyonov through the pylons, and the cavity of the rod divided by a partition with nozzles for supplying refrigerant in said compartments, characterized in that the reflecting conical surface of Aksyonov mounted on the ends of the hollow rod and the wall of the rod is made with a through axial holes, the diameter of the axial bore of conical reflecting surface Aksyonov mounted on the ends of the hollow rod, commensurate with the spot diameter of the focused laser beam and the axial hole of the partition rod and conical reflecting surfaces Aksyonov mounted on the ends of the hollow rod, isolated from the compartments CTE is life sealed hollow elements.
3. The device according to claim 2, characterized in that the hollow sealed elements are in the form of thin-walled tubes mounted coaxial conical reflecting surfaces of Aksyonov at the ends of the hollow rod and the axial hole of the partition walls of the terminal.
SUBSTANCE: proposed optoelectronic transmitter has laser and optoelectronic converter. Newly introduced in device are electrooptic modulator, three mirrors, and first and second correcting lenses. Optical output of laser is coupled with optical input of optoelectronic converter through electrooptic modulator affording radiation output from optoelectronic converter; it also has three mirrors and first correcting lens ensuring parallelism of radiation flux. Optical output of optoelectronic converter that functions to provide for shaping output radiation at frequency exceeding laser radiation frequency is coupled through second correcting lens with optical input of laser for pumping the latter.
EFFECT: enhanced radiation power raised without using large components.
1 cl, 1 dwg
FIELD: pulsed solid state lasers; high-power nanosecond radiation pulse generation.
SUBSTANCE: proposed system has two solid state lasers using electrooptically Q-switched cavity and parametric light oscillators. There are master lasers and amplifiers. Two active elements of master lasers having polished side surface are placed in single-lamp light. Two active elements of amplifiers are placed in other single-lamp light. Each amplifier is connected in double-pass ring circuit. The latter has first polarizer, polarization plane 90 deg. shifter, active element, second polarizer, first rotary mirror, telescope, dual-beam refraction plate, and second rotary mirror, all arranged in tandem.
EFFECT: enhanced stability of radiation pulse parameters and operating reliability, reduced mass and size.
1 cl, 1 dwg
FIELD: laser engineering; emission-line narrowing devices built around diffraction grating.
SUBSTANCE: emission-line narrowing device has diffraction grating, master working side of diffraction grating, chamber for accommodating at least mentioned diffraction grating, helium source for blasting mentioned chamber, beam expanding device that functions to expand mentioned laser beams, turning gear for guiding mentioned expanded beam to working side of diffraction grating to select desired wavelength range from mentioned expanded beam. Method for regulating laser frequency dispersion involves guiding of gaseous helium flow to working side of diffraction grating; in the process pressure of blast gas is reduced to cut down optical effects of hot gas layer.
EFFECT: minimized thermal distortions in narrow-line lasers generating high-power and high-repetition-rate beams.
15 cl, 12 dwg
FIELD: laser engineering.
SUBSTANCE: proposed device has pumping unit, resonator, semiconductor mirror, output lens, and input lens. Optical output of pumping unit is optically coupled with resonator whose optical output is coupled through semitransparent mirror with optical input of output lens. Newly introduced in device are optically controlled transparent amplifier, additional light source whose frequency exceeds resonator radiation frequency, three reflecting mirrors, and one more semitransparent mirror. Resonator optical output is coupled in addition through semitransparent mirror with first optical input of optically controlled transparent amplifier whose second optical input is coupled through additional semitransparent mirror with output of additional light source and optical output is coupled through three reflecting mirrors, additional semitransparent mirror, and second lens with resonator for its additional pumping.
EFFECT: enhanced power without increasing device mass.
1 cl, 1 dwg
FIELD: laser engineering; tunable lasers.
SUBSTANCE: laser has case accommodating cavity incorporating active medium, output mirror, and spectral-selective element in the form of diffraction grating. Grating set up in bezel is connected through first adjusting mechanism to loose end of moving lever. Other end of the latter is locked in position by means of spherical supports in U-shaped flange connected through second adjusting mechanism to laser case. Loose end of moving lever is kinematically coupled with micrometer screw. Provision for individual and independent adjustment of dispersion plane of diffraction grating and axis of revolution of moving lever, with this position being maintained in the course of operation, ensures steady and reliable functioning of laser under all mechanical and environmental impacts.
EFFECT: enhanced, reliability, reproducibility and precision of wavelength selection.
1 cl, 3 dwg
FIELD: X-ray diffraction and X-ray topography methods for studying the structure and quality control of materials during nondestructive testing.
SUBSTANCE: the invention is intended for X-ray beam shaping, in particular, the synchrotron radiation beam, by means of crystals-monochromators. The device for X-ray beam shaping has two crystals-monochromators in the dispersionless diffraction scheme. It is ensured by the possibility of displacement of one from crystals in the direction of the primary beam with crystal fixing in two discrete positions. Both crystals-monochromators have the possibility of rotation for realization of the successive Bragg diffraction. Device for crystal bending has displacement mechanism, two immovable and two movable cylindrical rods, between of which the end parts of a bent crystal are located. The axes of these parts are displaced one in respect to the other. The immovable rods are leaned against the upper surface of a flat parallel plate near its end faces. The L-shaped brackets are attached to the end faces of plate. The parallel surfaces of the brackets contact with immovable rods. The parallel surfaces of the end faces of the upper joints of L-shaped brackets contact with movable rods. The plate with L-shaped brackets is embraced with crooked shoulders of floating rocker with cylindrical pins, installed on the rocker ends. The pins are leaned against the surfaces of movable rods perpendicularly to them. The displacement mechanism is located between the lower surface of plate and middle point of the rocker.
EFFECT: increasing the energy range of X-ray beam when maintaining its spatial position; improving the uniformity of bending force distribution and homogeneity of crystal deformation.
2 cl, 2 dwg
FIELD: nuclear physics.
SUBSTANCE: device realizes electric magnet for spectroscopy of decomposition of neutron, with current configuration, providing magnetic field of 1/R type, where R - radial distance from device axis. Magnet includes no iron and field is fully absent at distance of near 25 cm and more from its outer surface. Device has two hollow semi-cylinders which connect through Φ-like flanges. This capability is achieved due to use in construction of each semi-cylinder of two coaxial semi-pipes, supported by their edges by setting grooves of flanges, containing elements for pressurization and centering.
EFFECT: higher trustworthiness, higher reliability, higher durability, higher precision.
FIELD: radiation shielding and masking systems, those producing illumination effects (advertisement, decorative lights), data display systems.
SUBSTANCE: proposed device that can be used for dissipating electromagnetic radiation, such as light, radio waves, X-rays, as well as for dissipating particle streams is, essentially, multilayer screen some of whose layers are deformable ones. Electric field is built up between two electricity conducting layers due to voltage applied to these layers. In the process conducting layers are split into segments and separate electrodes are brought to respective layers. Voltage applied to separate segments permanently varies with the result that electric field produced is nonuniform and deformable layers are embossed due to nonuniformity of attractive forces between electrodes, this embossed pattern permanently changing its configuration. Radiation (light of different ranges, radio and electromagnetic waves, particle streams) passed through screen or reflected therefrom dissipate due to optical nonuniformity. Kind of dissipation continuously varies due to changes in embossed pattern. Segments of conducting layers can be energized obeying different laws including pseudorandom one.
EFFECT: reduced specific surface power of incident radiation.
4 cl, 2 dwg
SUBSTANCE: proposed process includes layer-by-layer cross-linking of photopolymerizing molecules by means of focused optical radiation to produce spatially confined X-ray passages disposed within X-ray absorbing material. To this end X-ray absorbing material is added in advance to photopolymerized material, and collimator space, except for X-ray passages, is cross-linked using photochemical method.
EFFECT: enhanced spatial resolution and convergence of spatially confined X-ray passages into single point; reduced cost of process.