Comparison of BaTiO₃ Optical Novelty Configuration and Photothermal Lensing Configuration inPhotothermal Experiments

Authors

Shashi D. Kalaskar
Stephen E. Bialkowski, Utah State UniversityFollow

Document Type

Article

Journal/Book Title

Analytical Chemistry

Publication Date

1992

Volume

64

First Page

1824

Abstract

Photorefractlve BaTiO₃ Is used as an optlcal novelty fllter to highlight the hlgh spatlal frequency components of the photothermal signal. A real-time phase gratlng recorded In BaTiO₃ acts as a matched rejectlon spatlal filter for the probe laser. This reduces the statlonary background from the optical signals thereby Increasing slgnal contrast ratlos. Rejectlon of the monotonous statlonary slgnal provides a powerful means of Improving the photothermal signal. This paper describes the constructlon of this novel apparatus and the experlments performed In order to compare lts performance wlth photo- thermal lensing results. A theory that explains photothermal signal fllterlng wlth BaTiO₃, as an adaptive spatlal frequency fllter is presented. Results comparlng the optical signals obtalned In a photothermal lensing experiments and those obtalned In the BaTiO₃ optlcal novelty fllter experlments are presented. The optical novelty fllter signals demonstrate a remarkable Improvement In the signal contrasts for moderate photothermal-lnduced phase shifts.

Recommended Citation

Comparison of BaTiO3 Optical Novelty Configuration and Photothermal Lensing Configuration in Photothermal Experiments Shashi D. Kalaskar and Stephen E. Bialkowski Analytical Chemistry 64 1824 1992