Abstract

We demonstrated the gyro response of a mode-locked femtosecond ring laser gyro (λ = 628 nm) with no resolvable lock-in at rotation rates of less than 0.1° per second. The key to such a response is that the counter-propagating pulses in the cavity meet in only two places, thus providing minimal opportunity for coupling to occur between the pulses. We investigated the role of short pulse operation on the gyro response by: (1) creating a deadband with a 2 mm thick piece of anti-reflection (a-r) coated glass at the pulse-crossing point, and (2) spectrally narrowing the counter-propagating pulses before detection of the beat frequency between them.

© 1993 Optical Society of America