BG64575B1 - Method and device for optic stop and spectral selection of laser radiation - Google Patents

Abstract

The method and the device for optic stop and spectral selection of laser radiation, in particular of gas lasers with copper vapours and copper halogenides can be used in the materials processing industry, in the field of dermatology, in laser systems for lighting and lighting effects, laser location, accelerated photography, research and others. It enables the possibility for a quick optic stop and spectral selection of laser radiation and their application in the entire power range of copper vapours and of copper halogenide lasers, furthermore without any optic losses due to which the complete power of lasers can be attained. The initial radiation is linearly polarized, thus extending the facilities for its application. By the method the control of the gas laser copper vapours or copper halogenides control is effected by internal resonance effect, by polychromatic acoustic-and-optical modulation on the initiating low-power injection signal. The device comprises copper vapour or copper halogenide gas laser with an unstable resonator in which, in the direction of the initiating low-power injection signal, polychromatic acoustic-and-optic modulator (4) and reflection mirror (5) are fitted.

Description

Technical field

The invention relates to a method and apparatus for optical stop and spectral selection of laser radiation, in particular for copper or copper halide gas lasers used in the materials processing industry, dermatology medicine, laser systems for the treatment of dermatology. lighting and light effects, laser location, high-speed photography, research and more.

BACKGROUND OF THE INVENTION

There is a method of optical stop, in which the optical stopping of the laser radiation is achieved by asynchronous operation of two consecutive active media (1).

An optical stop method is known in which the optical stopping of the laser radiation is achieved by additional electrical impulses that disturb the inverse population in the active medium of the laser 12 /.

A method of optical stop and spectral selection of laser radiation is known, in which the laser radiation is externally affected by an acousto-optical cell. The method is applicable only to linearly polarized, small-aperture, and low-density laser radiation, with large optical losses in them.

Spectral selection of laser radiation by means of spectral selection elements, such as an optical prism, diffraction grating, or optical filters, is known.

There is no known method for optical stop and spectral selection of laser radiation from gas vapors with copper vapors and copper halides having an intracavity effect.

SUMMARY OF THE INVENTION

The method of optical stop and spectral selection of laser radiation from copper or copper halide vapor gas lasers involves the control of laser generation by intracavity influence by polychromatic acousto-optic modulation on the initiating low-power injection signal.

The optical stop and laser spectral selection device consists of a copper or copper halide vapor laser with an unstable resonator in which a polychromatic acousto-optical modulator and a reflecting mirror are placed on the optical path of the low-power injection signal initiator.

The method and the device allow for fast optical stop and spectral selection of the laser radiation and their application over the entire power range of copper vapor or copper halide lasers, with no optical losses resulting in full utilization of the laser power and the output radiation is linearly polarized, which widens the possibilities for its application.

Description of the attached figure

The figure shows a schematic diagram of a device for optical stop and spectral selection of laser radiation.

An exemplary embodiment of the invention

According to one embodiment, the optical stop and laser spectral selection device includes a copper or copper halide vapor gas laser with an unstable resonator in which the copper or laser halogenide gas laser initiating signal is optically positioned by the optical path polychromatic acousto-optic modulator 4 and a reflecting mirror, for example a short-focusing spherical mirror 5.

According to another exemplary embodiment of the device shown in the accompanying figure, it includes a copper bromide vapor laser consisting of a laser tube 2 located on a common optical axis with a long-focussed spherical mirror 1 on one side and a planar-pair mirror with an opening 3 on the other side, the aperture being coincident with the optical axis, and the mirror having an angle of 45 ° to it, followed by a polychromatic acousto-optical modulator 4 and a short-focussed recessed spherical mirror 5 at an angle to the optical axis.

According to an exemplary embodiment of the method, part of the spontaneous emission beams emitted by the laser tube 2 propagating as close as possible to the main optical axis of the laser resonator pass through the aperture of the plane-parallel mirror 3 and fall on the polychromatic acousto-optical modulator 4, which in the absence of an electrical RF signal deflects them in “0” order. In this case, the polychromatic acousto-optic modulator 4 has the property of a dispersing optical prism, whereby in the “0” order the spectral separation of the two laser lines contained in the spontaneous radiation is observed. When transmitting an electrical frequency signal to the polychromatic acousto-optical modulator 4 corresponding to the optical tuning of one of the two wavelengths λ and λ ₂ of the spectral lines or both simultaneously, the modulator 4 acquires the properties of a diffraction grating and deflects one of the the two spectral lines or both together in the order “1”. Perpendicular to the direction of the order "1" is placed the short-focal spherical mirror 5, which forms the optical feedback leading to laser generation in the unstable resonator. The reflected and retransmitted light from the short-focal spherical mirror 5 is the optical injection controlled by the polychromatic acousto-optical modulator 4, which initiates laser emission. Depending on the electrical RF signal, feedback can be generated, both individually and together for existing laser lines. It can thus selectively control which line the laser generates, and also stop the laser generation when the radio frequency signal is stopped. The response time of such a system is below 100 ns, which provides the possibility of very fast stopping, starting and spectral selection of laser radiation.

Application of the invention

The method and apparatus for optical stop and laser spectral selection are used in copper or copper halide gas lasers, thereby extending their application to the precision materials industries, medicine, in particular in dermatology, in the removal of cosmetic defects and with applications in ophthalmology, in laser systems used for lighting and light effects, in the laser location for the remote determination of gases in the atmosphere, in high-speed gating liquid chromatography have to study the emerging processes in research and others.

Claims (3)

Claims 1. Method for optical stop and spectral selection of a laser gas with a copper metal vapor and copper halides with an unstable resonator, characterized in that the control of the laser generation of the copper vapor or copper halide vapor is by intracavity influence by polychromatic acoustic-optical modulation on the initiating low-power injection signal. 2. Optical stop and spectral selection device for laser radiation, a copper vapor gas laser or a copper halide with an unstable resonator, characterized in that the unstable resonator of a copper vapor gas laser or copper halide on the optical a polychromatic acousto-optic modulator (4) and a reflecting mirror (5) are sequentially located on the path of the low-power injection signal. Device according to claims 1 and 2, characterized in that in the unstable resonator of a copper or copper halide vapor gas laser between a planar mirror (3) with an aperture and a short-focussed spherical mirror (5) on the common optical axis , the polychromatic acousto-optical modulator / 4 / is located.