Thermal lensing in biologic medium

Author

Motamedi, M. ; Welch, Ashley J. ; Cheong, Wai-Fung ; Ghaffari, Shahriar A. ; Tan, Oon Tian

Author_Institution

Dept. of Electr. & Comput. Eng., Texas Univ., Austin, TX, USA

Volume

24

Issue

4

fYear

1988

fDate

4/1/1988 12:00:00 AM

Firstpage

693

Lastpage

696

Abstract

A nonlinear effect for tissue response is reported which results from macroscopic changes in the refractive index of tissue due to its localized heating during laser irradiation. The effect, termed thermal lensing, arises when a high-intensity beam of light interacts with an absorbing medium and highly localized heating occurs. Localized heating causes thermal expansion which leads to a decrease in tissue density, inducing macroscopic spatial gradients in the index of refraction. A description is given of a series of experiments designed and performed to establish the existence of thermal lensing in a biological medium and quantify the effect of exposure parameters and medium properties

Keywords

biological effects of laser radiation; biothermics; absorbing medium; biologic medium; exposure parameters; high-intensity beam; laser irradiation; localized heating; macroscopic changes; macroscopic spatial gradients; medium properties; nonlinear effect; refractive index; thermal expansion; thermal lensing; tissue density; tissue response; Argon; Free electron lasers; Heating; Laser beams; Lenses; Optical refraction; Power lasers; Refractive index; Temperature distribution; Thermal lensing;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/3.180

Filename

180