Wavelength-selective light-shielding element and optical head using the same

Abstract

In order to provide a wavelength-selective light-shielding element capable of blocking circularly-polarized light beams rotating in a specific direction among light beams whose wavelengths falling in a specific range, a light-shielding region is provided in a portion of a transparent substrate, wherein the light-shielding region permits passage of first circularly-polarized light rotating in a first direction regardless of a wavelength of the first circularly-polarized light and blocks second circularly-polarized light beams whose wavelengths falling within a predetermined range, among second circularly-polarized light beams rotating in the second direction, to thus permit passage of the second circularly-polarized light beams falling outside the predetermined range.

Dependencies are inferred from the claim text.