Fabrication of laser beam axis compensator by photonic crystal technique for optical pickup units

Abstract

A laser beam axis compensator was fabricated for an optical pickup unit with blue and red lasers. The device consisted of multiwavelength wave plates and a double-refractive-index material. The wave plates were realized by a photonic crystal technique. By measuring the beam profiles of the blue and red lasers, the device was confirmed to function as a laser axis compensator. Under 110 μm laser beam axis shift setting conditions, readout signal patterns from an optical disc were measured. © 2006 The Japan Society of Applied Physics.