Scanning delay line with a rotating-parallelogram prism for low-coherence interferometry.
We describe a fast scanning optical delay line for low-coherence interferometry that has good linearity, a high duty cycle, and a continuously adjustable scan range. The delay line consists of a rotating-parallelogram prism with the rotation axis tilted with respect to the incident beam and two motionless mirrors. The delay line is well suited for nearly simultaneous distance measurements at two different depths, which is useful for making absolute and differential distance measurements.
Giniūnas
L
L
Laser Research Center, Vilnius University, Sauletekio al 10, Vilnius LT-2040, Lithuania. Linas.Giniunas@ff.vu.lt
Danielius
R
R
Karkockas
R
R