文献类型： 会议论文

第一作者： Michael Scaggs

作者： Michael Scaggs ¹ ; Gil Haas ² ;

作者机构： 1.Neoteric Concepts, LLC, 1612 Eastlake Way, Weston, FL 33326

2.Haas Laser Technologies, Inc. 37 Ironia Road, Flanders, NJ 07836

关键词： thermal lensing;athermalization;high power lasers;fiber collimator;focus lens

会议名称： SPIE Conference on Laser Resonators and Beam Control

主办单位：

页码： 79130C:1-79130C:9

摘要： Athermalization of focusing objectives is a common technique for optimizing imaging systems in the infrared where thermal effects are a major concern. The athermalization is generally done within the spectrum of interest and not generally applied to a single wavelength. The predominate glass used with high power infrared lasers in the near infrared of one micron, such as Nd:YAG and fiber lasers, is fused silica which has excellent thermal properties. All glasses, however, have a temperature coefficient of index of refraction (dn/dT) where as the glass heats up its index of refraction changes. Most glasses, fused silica included, have a positive dn/dT. A positive dn/dT will cause the focal length of the lens to decrease with a temperature rise. Many of the fluoride glasses, like CaF_2, BaF_2, LiF_2, etc. have a negative dn/dT. By applying athermalization techniques of glass selection and optical design, the thermal lensing in a laser objective of a high power laser system can be substantially mitigated. We describe a passive method for minimizing thermal lensing of high power laser optics.

分类号： N532