Polarizing optical element and device using the same
First Claim
1. A polarizing optical element which comprises a first substrate having a first surface whose contour is modulated, thereby forming only first and second relief gratings so as to cross relative to each other at a predetermined crossing angle, each of said first and second gratings having a grating pitch equal to or smaller than the wavelength of a laser beam which may be incident upon the polarizing optical element, wherein the diffraction efficiency of said gratings is dependent upon the polarization of said laser beam, thereby producing a transmitted or reflected beam and two diffracted laser beams responsive to the incident laser beam, said two diffracted laser beams having polarizations which are different from the incident laser beam.
1 Assignment
0 Petitions
Accused Products
Abstract
A polarizing optical element which comprises a first substrate having a first surface formed with first and second gratings so as to cross relative to each other at a predetermined crossing angle, each of which first and second gratings has a grating pitch equal to or smaller than the wavelength of a laser beam which may be incident upon the polarizing optical element. A magneto-optical head system of a type comprising a laser source for emitting and projecting a laser beam on a magneto-optical recording medium and utilizing a magneto-optical effect for reading information, recorded on the magneto-optical recording medium, by the utilization of reflected or transmitted laser beams reflected from or transmitted through the magneto-optical recording medium and utilizing the polarized optical element is also disclosed.
-
Citations
13 Claims
- 1. A polarizing optical element which comprises a first substrate having a first surface whose contour is modulated, thereby forming only first and second relief gratings so as to cross relative to each other at a predetermined crossing angle, each of said first and second gratings having a grating pitch equal to or smaller than the wavelength of a laser beam which may be incident upon the polarizing optical element, wherein the diffraction efficiency of said gratings is dependent upon the polarization of said laser beam, thereby producing a transmitted or reflected beam and two diffracted laser beams responsive to the incident laser beam, said two diffracted laser beams having polarizations which are different from the incident laser beam.
Specification