RU1567058C - Method of adjusting laser resonator - Google Patents

Abstract

The invention relates to quantum electronics. The purpose of the invention is to increase the accuracy of alignment. The auxiliary radiation source is introduced into the tunable resonator, the active medium is excited, and auxiliary radiation is distributed in two opposite directions. The radiation is then converted into ring beams and matched in focus with the mirrors of the resonator. The adjustment is completed at the maximum intensity of the annular beams in two directions. 2 C.p. f-ls, 1 ill.

Description

The invention relates to quantum electronics, and in particular to methods for aligning and controlling the position of optical elements, and can be used to align laser resonators, which are predominantly unstable, in particular containing opaque mirrors and designed to operate in the invisible wavelength range, as well as for visualization and controlling the direction of the invisible laser beams and aligning the external optical systems for their transmission.

The purpose of the invention is to increase the accuracy of alignment.

The drawing shows an installation diagram for implementing this method.

In the resonator formed by mirrors 1 and 2, a laser cell is arranged, consisting of a cell 3 with translucent mirrors 4 and 5, between which the active medium 6 is placed. The laser cell is mounted on the optical axis of the resonator using a device 7, which is used to move the position of the cell and its fixation. The active medium is excited using a pump source 8, and the laser beams 9 and 10 that arise in two opposite directions are directed along the axis of the resonator, collimated by means of collimators 11 and 12, and converted by wedge systems 13 and 14 into circular rings by scanning in a circle. Using devices 15 and 16, rotational motion is transmitted to the optical wedges, and devices 17 and 18 are used to match the X-ray beams 19 and 20 with the cavity mirrors along the focal radius of curvature Ф | and F2, respectively, or with a resonator in focus F.

After completion, using the devices 21 and 22 of moving the mirrors of the resonator, the position of the beam of auxiliary radiation is noted, for example, by means of a screen located outside the

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ABOUT

of the resonator on its optical axis, and the laser cell and the elements of collimation and conversion into ring beams from the zone of the resonator output t.

The criterion for the exact alignment of the axes and the completion of the alignment of the resonator is a uniform increase in the intensity of the auxiliary radiation to the maximum possible throughout the ring, which is recorded visually or using photodetector equipment.

When using an annular beam in the direction of one of the resonator mirrors, e.g., mirror 1, actions similar to those occur. which are carried out during alignment with two-sided conversion of the ring beam, using elements 3-8 to generate auxiliary radiation, and after installing the uncollimated beam 9 in the center of the mirror 2, the beam 9 after collimation is transformed into a ring beam and provide optical feedback. After that, using the device 22, the mirror 2 is adjusted, the accuracy of which adjustment is judged by the system of concentric rings reflected by the mirrors. The adjustment is also completed by fixing the auxiliary radiation on the screen outside the cavity and removing elements 3-6 and 11. 13 from the cavity zone.

However, the accuracy of alignment of the resonator with one-sided transformation of the annular beam is somewhat lower than with the two-sided one, since in order to evaluate the quality of alignment in the first case, a larger number of passes of the annular beam is required, which entails a deterioration in the clarity of the image of concentric rings.

The accuracy of combining the optical axes of the auxiliary radiation and the resonator is estimated by the magnitude of the displacement of the ring beam, at which it is possible to detect a decrease in the radiation intensity relative to its maximum throughout the ring in the best matching mode of the ring beams with the corresponding resonator mirrors in focus

In this installation, at a distance from the source of auxiliary radiation to

a 2500 mm mirror and a scanning beam diameter in the mirror plane of 2 mm, a decrease in the intensity of auxiliary radiation during visual inspection is observed when the ring is displaced in the mirror plane by approximately 0.5 mm, which corresponds to an axis mismatch angle p of approximately 42 minutes (angular seconds) . Using photodetector equipment

Claims (3)

to control the deviation of the radiation intensity in the ring from the maximum value, it makes it possible to increase the alignment accuracy of the axes by about 5 times on the same setup, which is probably not a limit and depends on the quality of the collimation and scanning systems, as well as the method of recording auxiliary radiation . SUMMARY OF THE INVENTION 1. A method for aligning a laser cavity, including generating an auxiliary beam, converting it to annular, and determining the degree of alignment by the location of the concentric annular beams reflected from resonator mirrors, characterized in that, in order to increase the alignment accuracy, an auxiliary radiation beam is formed inside the aligned resonator along its axis in two opposite directions and, after being converted into a ring, they are reflected from the mirrors of the aligned resonator so that the intensities of the ring beams in two directions maximum. 2. A method according to claim 1, characterized in that the beam of auxiliary radiation is converted into circular beams by scanning in a circle. 3. The method according to PP. 1 and 2, characterized in that they are collimated before being converted into annular auxiliary beams.