Accession Number:

AD0749481

Title:

Thermal Lensing in Infrared Laser Window Materials

Descriptive Note:

Physical science research papers

Corporate Author:

AIR FORCE CAMBRIDGE RESEARCH LABS HANSCOM AFB MA

Personal Author(s):

• Gianino, P. D.
• Jasperse, J. R.

Report Date:

1972-03-23

Pagination or Media Count:

53.0

Abstract:

A theoretical investigation of thermal lensing in infrared windows is presented which treats aberration effects to all orders in the small angle-of- deviation approximation. The model is applied to a truncated, Gaussian, infrared laser beam incident on a semitransparent, isotropic, disc-shaped window. It is shown that window aberrations limit the time a diffraction-limited focus can be held in the far-field. This diffraction-limited time td is computer for some candidate window materials and their relative merits are discussed. Some approaches to solving the thermal lensing problem from both an engineering and a materials point of view, as well as some program research and development needs, are discussed.

Descriptors:

• *INFRARED LASERS
• *INFRARED WINDOWS
• OPTICAL PROPERTIES
• REFRACTIVE INDEX
• MATHEMATICAL ANALYSIS
• FOCUSING
• THERMAL STRESSES
• INFRARED OPTICAL MATERIALS
• THERMAL CONDUCTIVITY
• DIFFRACTION
• COHERENT RADIATION

Subject Categories:

• Lasers and Masers
• Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE