LAYERED WAVEPLATE AND OPTICAL PICKUP USING THE SAME

摘要

It is possible to provide a layered waveplate having a wide range with a desired phase difference. The layered waveplate (1) is formed by a first waveplate (2) and a second waveplate (3). The first waveplate (2) has a phase difference G1 = 360 degrees and an in-plane azimuth angle -8 degrees. The second waveplate (3) has a phase difference G2 and an in-plane azimuth angle 43.5 degrees. The first and the second waveplate are layered so that their optical axes intersect with an angle of 51.5 degrees. The layered waveplate functions as a desired phase difference G2 in a wavelength range 600 nm to 800 nm as a whole.