Subminiature rotary actuator optical head

摘要

A miniature rotary actuator optical head assembly incorporating data and servo detecting elements mounted inside a source/detector module, which is located on the rotary actuator arm adjacent to the pivot point of the rotary actuator arm. The miniature rotary actuator optical head also includes a miniature focus motor which supports a fold mirror and an objective lens and repositions the fold mirror and objective lens simultaneously whenever a focus error is received. The focus motor can be actuated by a magnetic bias field that originates external to the rotary actuator arm, particularly the magnetic bias field generated for magneto-optical recordation. The optical assembly may also include two stage tracking by mounting the light source on a pair of lateral movement flexures and supplying a fine tracking error signal to actuate the movement of the light source.