CN-122000777-A - Raman beam-combining laser amplifier

Abstract

A Raman beam-combining laser amplifier relates to the technical field of lasers and aims to solve the problem of low conversion efficiency of the existing beam-combining laser amplifier. The first bowl-shaped reflecting mirror and the second bowl-shaped reflecting mirror are coaxially arranged at two ends of the columnar reflecting mirror component, the concave faces face the columnar reflecting mirror component, the Raman laser crystal is arranged in the columnar reflecting mirror component, seed light output by the seed optical module is incident to the Raman laser crystal through the center of the first bowl-shaped reflecting mirror, and a plurality of fundamental frequency light output by the plurality of fundamental frequency optical modules is obliquely incident to the Raman laser crystal from the side face of the columnar reflecting mirror component. Each beam of fundamental frequency light of the Raman group beam laser amplifier can be reflected in the amplifier for multiple times and interacted with seed light for multiple times, so that the conversion efficiency of single Shu Jipin light is improved, the fundamental frequency light module is low in adjustment difficulty, and the Raman group beam laser amplifier is suitable for integrated use.

Inventors

• WANG YULEI
• GAO HANLIN
• ZHENG HAO
• ZHAO XIAONAN
• BAI ZHENXU
• LV ZHIWEI

Assignees

• 河北工业大学

Dates

Publication Date

20260508

Application Date

20260125

Claims (7)

1. 1. The Raman beam-combining laser amplifier is characterized by comprising a first bowl-shaped reflecting mirror, a second bowl-shaped reflecting mirror, a columnar reflecting mirror component, a Raman laser crystal, a seed optical module and a plurality of fundamental frequency optical modules; The first bowl-shaped reflector, the second bowl-shaped reflector and the columnar reflector component are coaxially arranged, the first bowl-shaped reflector and the second bowl-shaped reflector are respectively positioned at two ends of the columnar reflector component, the concave surfaces of the first bowl-shaped reflector and the second bowl-shaped reflector face the columnar reflector component, and the Raman laser crystal is arranged inside the columnar reflector component; The seed light output by the seed light module is incident to the Raman laser crystal through the center of the first bowl-shaped reflecting mirror, and the plurality of fundamental frequency light output by the plurality of fundamental frequency light modules is obliquely incident to the Raman laser crystal from the side surface of the columnar reflecting mirror component.
2. 2. A raman group beam laser amplifier according to claim 1 wherein said plurality of fundamental frequency optical modules are circumferentially distributed.
3. 3. A raman group beam laser amplifier according to claim 2 wherein said plurality of fundamental light beams are incident to said raman laser crystal from one end of said cylindrical mirror assembly.
4. 4. A raman group beam laser amplifier according to any one of claims 1 to 3 wherein said columnar mirror assembly comprises two columnar mirrors, one end face of said columnar mirrors being notched, and both ends of said raman laser crystal being embedded in the notches of both said columnar mirrors, respectively.
5. 5. A raman group beam laser amplifier according to claim 3 wherein an angle of incidence of said fundamental light into said cylindrical mirror assembly is about 30 degrees or about 45 degrees.
6. 6. A raman group beam laser amplifier according to claim 3 wherein an angle of incidence of said fundamental light into said cylindrical mirror assembly is determined by: According to the formula Calculating the total Raman gain Fundamental light incidence angle at maximum , wherein, For the raman gain coefficient of the raman laser crystal, Is the fundamental frequency optical power, and is used for generating the optical signal, For the height of the raman laser crystal 3, Is half the length of the cylindrical mirror assembly, For the radii of curvature of the first bowl-shaped mirror and the second bowl-shaped mirror, In order to consume the factor(s), Is the cross-sectional area of the beam of the fundamental frequency light.
7. 7. A raman beam-combining laser amplifier according to claim 3 wherein the raman laser crystal is diamond, yttrium vanadate, potassium gadolinium tungstate, barium nitrate or lithium iodate.

Description

Raman beam-combining laser amplifier Technical Field The invention relates to the technical field of laser, in particular to a solid laser amplifier. Background Lasers ask oneself have been widely used in various fields, and the output power of lasers is a very important performance parameter in laser applications, and comprehensive researches have been conducted to obtain higher laser output. The most direct way is to increase the input power of the laser, but with the increase of the input power, the laser generates serious thermal effect, when the damage threshold of the laser is broken through, the laser device is damaged, the conversion efficiency of a single laser crystal has an upper saturation limit, and in order to further obtain higher laser output, a laser amplifier is developed. The laser amplifier is to make the seed light needing to be amplified incident on the laser crystal, so that the incident fundamental frequency light is converted into seed light to achieve the purpose of amplifying laser power. The amplifier has no resonator because seed light is required to pass through it. Thus, multi-pass laser amplification techniques have been developed. The method can make laser pass through the laser crystal for multiple times to perform gain conversion amplification by utilizing the characteristics of polarized light, or make the laser pass through a plurality of laser crystals, and make the laser pass through the laser crystal for one time to perform gain conversion of fundamental frequency light to seed light so as to achieve the amplification effect, and make the seed light enter the laser crystal at a certain angle and then be reflected by a reflecting mirror so as to make the laser pass through the laser crystal for multiple times to improve the laser gain to amplify the seed light. On-axis multipass amplification, while having higher conversion efficiency, can cause increased thermal effects of local power density increase, and may damage the device when the damage threshold of the crystal is exceeded. And the light enters the resonant cavity at a certain angle, so that the resonant cavity is regulated and controlled with certain requirements, and the specific implementation is quite difficult. The beam combining laser amplifier is different in that a plurality of fundamental frequencies are optically coupled to amplify one beam of seed light, and the aim of improving the conversion efficiency of gain and fundamental frequency light is achieved by increasing the quantity of the fundamental frequency light instead of the passing times of the seed light. The solid laser beam-combining amplifying laser in the present stage mainly has two kinds, one is to make multiple beams of fundamental frequency light pass through a certain matrix arrangement and combination of incidence angles, and couple the beams to pass through in one pass in a laser crystal, and the other is to change the crystal shape, so that the optical path of the passed fundamental frequency light in the crystal can be increased, or the same effect can be achieved by using a complex resonator design, the former has very high requirements on optical device adjustment, crystal growth size and processing technology, the more times the latter passes through the fundamental frequency light in the crystal, the complexity and adjustment difficulty of the resonator can also be increased, and the times of passing through the fundamental frequency light are mostly limited, and the conversion efficiency is still lower. Disclosure of Invention The invention aims to solve the problems of complex structure and low conversion efficiency of the existing beam-combining laser amplifier and provides a Raman beam-combining laser amplifier with simple structure, low adjustment difficulty and high conversion efficiency. The Raman beam-combining laser amplifier comprises a first bowl-shaped reflecting mirror, a second bowl-shaped reflecting mirror, a columnar reflecting mirror assembly, a Raman laser crystal, a seed optical module and a plurality of fundamental frequency optical modules, wherein the first bowl-shaped reflecting mirror, the second bowl-shaped reflecting mirror and the columnar reflecting mirror assembly are coaxially arranged, the first bowl-shaped reflecting mirror and the second bowl-shaped reflecting mirror are respectively positioned at two ends of the columnar reflecting mirror assembly, concave surfaces of the first bowl-shaped reflecting mirror and the second bowl-shaped reflecting mirror face the columnar reflecting mirror assembly, the Raman laser crystal is arranged in the columnar reflecting mirror assembly, seed light output by the seed optical module is incident to the Raman laser crystal through the center of the first bowl-shaped reflecting mirror, and a plurality of fundamental frequency light output by the plurality of fundamental frequency optical modules are obliquely incident to the Raman laser crystal from the side