Double-pass absorption spectral matching laser amplifier and amplifying method thereof

Abstract

The invention discloses a double-pass absorption spectral matching laser amplifier and an amplifying method thereof. The laser amplifier comprises a pump light focusing lens, a double-color coupling mirror, a polarization selecting mirror, a gain medium, a curve face double-color coupling mirror, a one fourth wave plate, a curve face total reflection mirror, a seed laser focusing lens and a total reflection mirror, wherein the polarization selecting mirror, the gain medium, the curve face double-color coupling mirror, the one-fourth wave plate and the curve face total reflection mirror are sequentially distributed on the same optical axis, and the seed laser focusing lens and the total reflection mirror are arranged in the direction parallel to the optical axis. Polarization seed laser and pump light are respectively emitted into the focus lens and enter to optical structure to be subjected to double-pass absorption and laser amplification, and after the seed laser is amplified, output laser with different seed laser polarization states is output. The amplifier and the amplifying method effectively utilize the pump light, and light-laser converting efficiency is improved.

Description

Technical field: [0001] The invention relates to the field of lasers, in particular to a double-pass absorption splitting matching laser amplifier and an amplification method thereof. Background technique: [0002] Since the laser was invented in 1960, it has been widely used in many fields, such as lidar, remote sensing, medicine, optical communication, laser display, laser processing and other fields. In many fields, high-energy spot mode and good laser output are an important requirement for lasers. [0003] Traditional end-pumped laser amplifiers are single-pass pumped, that is, the pump light passes through the gain medium once. Such lasers often have low amplification efficiency due to the inability to effectively absorb the pump light, which leads to waste of energy and reduces The conversion efficiency of the laser will also lead to the heating of the medium in the laser, which will deteriorate the quality of the output light [0004] For example, the prior art CN1...

AI Technical Summary

Problems solved by technology

The laser has defects such as low pump light absorption efficiency and crystal heating

After adding optical elements such as lenses in the optical path, although the pump light is focused, the addition of optical elements will lead to a large overall optical loss of the laser and a decrease in the reliability of the system.

[0005] In order to solve the above problems, there are currently some commonly used methods and devices for increasing pump light absorption in the field, but they all have their own shortcomings, which prevent them from being widely used.

If the length of the laser crystal is increased, it often occurs that the pump light has a large divergence angle in the crystal, resulting in a larger spot, which makes the pump power density in most areas of the crystal along the axial direction low and cannot be effectively extracted; increase the doping concentration , it will strengthen the absorption of pump light, but in most cases, due to the increase of self-absorption loss due to high concentration, the amplification efficiency will be reduced

Images