Toric concave mirror laser resonator with a big Fresnel number.
A new type of toric concave mirror laser resonator with a big Fresnel number is presented. The M2 factor of an output laser beam of the new resonator with a Fresnel number of 8.05 is close to that of the plane-concave stable resonator with a Fresnel number of 2.01, the volume of output mode of the new resonator is about four times of that of the plane-concave stable resonator. A 3.2 kW doughnut-like laser beam with an M2 factor of 1.9 is obtained experimentally by using the new resonator on a high-power transverse flow CO2 laser, while the similar laser power with an M2 factor of 7.5 is obtained by using a plane-concave stable resonator with the same Fresnel number. Results show that a toric concave mirror laser resonator can permit operation of the laser with high power and high beam quality mode in the laser with large gain volume.
Yingxiong
Qin
Q
Wuhan National Laboratory for Optoelectronics, National Engineering Research Center for Laser Processing, School of Optoelectronics Science and Engineering, Huazhong University of Science and Technology, Hubei, China.
Xiahui
Tang
T
Yu
Xiao
X
Juan
Liu
L
Du
Wang
W
Hao
Peng
P
Qiansong
Deng
D
Xiao
Zhu
Z
Zhengjia
Li
L