PHASE SHIFTER AND OPTICAL HEAD DEVICE

摘要

PROBLEM TO BE SOLVED: To obtain an optical head device capable of stably detecting signals by obtaining an optical element which converts linearly polarized light composed of two kinds of wavelengths having mutually parallel planes of polarization into that having mutually perpendicularly intersecting planes of polarization. SOLUTION: The phase shifter 101 is constructed by laminating a birefringent organic thin film 14 between two transparent substrates 11, 16 via an adhesive 15 so as to make the organic thin film 14, imparts 2π (m1-1/2) phase difference to the polarized light of the one wavelength and 2πm2 phase difference to the polarized light of the other wavelength and is mounted on the optical head device.