Taking Optical Interferometry out of the Laboratory through
Nonlinear Electro-Optics
Dr. Ken Telschow
Physics Group
Idaho National Laboratory
Adaptive optical interferometry utilizes optically generated self-correction
to automatically stabilize operation and reduce dependence on low frequency
noise. A nonlinear electro-optic effect, known as photorefractivity,
provides a means for any optical wavefront to generate its conjugate wavefront
and undergo complete interference automatically. This effect is being exploited
today to perform interferometric measurements in nonlaboratory, industrial
and often hostile environments. The physics behind the photorefractive effect
is described along with its use for both single collimated beam and full-field
imaging of highly distorted wavefronts. Examples are presented of its use
for remote measurement of subnanometer acoustic/ultrasonic motion at the
surface of materials from Hz to GHz for commercial use and for measurements
in high radiation environments.