Optical waveguide recording medium playing apparatus.

摘要

An optical waveguide recording medium playing apparatus, which has a heterodyne detection optical system, uses a waveguide light delaying/reflecting device (37) to generate reference light. This waveguide light delaying/reflecting device (37) is provided with a transducer (101) which generates a surface elastic wave, so that the surface elastic wave may propagate in the light propagating direction of an optical waveguide (100). Reference light from a laser beam is guided onto the optical waveguide (100), and a high-frequency drive current modulated in burst form is applied to an electrode (101) to generate a surface elastic wave, thereby accomplishing the shifting and phase delay of the light frequency of the reference light, which ensures information reproduction, through the interaction of the laser beam and the surface elastic wave. The frequency-shifting as well as phase delay of the reference light due to the Doppler effect may also be accomplished by using an acoustooptic modulating element (37) and driving it by a burst modulation signal. The acoustooptic modulating element comprises a bulk crystal block (100) of Te02, for example, and an ultrasonic wave generating element (101) with an opening (101a) formed in one end thereof through which a laser beam enters in such a way that the beam incident direction becomes parallel to the ultrasonic propagating direction.