Fundamental mode radiation with solid-state lasers

Author

Steffen, Jürg ; Lortscher, Jean-Pierre ; Herziger, G.

Author_Institution

Institute of Applied Physics, Univ. of Berne, Berne, Switzerland

Volume

8

Issue

2

fYear

1972

fDate

2/1/1972 12:00:00 AM

Firstpage

239

Lastpage

245

Abstract

Optical pumping of solid-state lasers induces thermal lensing in the laser crystal. This lansing determines the beam properties in the resonator; the TEM00-mode radiation is limited to a small laser rod volume and it depends on the pump power. Especially with pulse-pumped systems, the generation of stable fundamental mode radiation could only be obtained with low efficiency. Laser resonators with optimum TEM00mode output were studied considering the thermal lensing. A kind of resonator was found, the radiation of which is insensitive to thermal distortions. The following is determined by parameters $g_{1}, g_{2}$ : $frac{1}{g_{1}}=2g_{2} +^{1} (frac{a}{b})^{2} + 2frac{a}{b}$ , where $a$ and $b$ are distances between rod ends and mirrors, $a$ and $b$ being the distances between the two mirrors and the lens. The predicted beam behavior was verified experimentally with a high repetition rate YAG laser. A high-precision laser drilling machine was constructed with this design. Because of the insensitive properties, reproducible material processing was achieved in industrial use.

Keywords

Laser beams; Laser excitation; Laser modes; Mirrors; Optical pulse generation; Optical pumping; Optical resonators; Pump lasers; Solid lasers; Thermal lensing;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/JQE.1972.1076948

Filename

1076948