Patent ID: 6072607
Filing Date: 2000-06-06
Classification: G02B,G11B,H01L

Abstract:
An optical pickup device for a reflective type optical recording medium, comprising:a single piece flat board type substrate having an upper surface;a semiconductor laser mounted on said substrate upper surface for emitting a laser beam in a first direction substantially parallel to said substrate upper surface;a transmission-type diffraction grating on said substrate upper surface disposed substantially perpendicular to said substrate upper surface for receiving the laser beam from said laser, splitting the laser beam passing through said grating into at least three beams and guiding them substantially in said first direction forwardly of said diffraction grating;a hologram mounted on said substrate substantially perpendicular to said substrate upper surface for receiving the at least three beams transmitted through said diffraction grating and guiding them substantially in said first direction forwardly of said hologram so as to be incident on an optical recording medium and reflected from said optical recording medium;a photodetector for signal detection with a photodetecting surface parallel with said substrate upper surface for receiving the at least three beams reflected from the optical recording medium, and redirected by said hologram onto said photodetecting surface; anda plurality of electrodes formed directly on the upper surface of said substrate, each of said electrodes connected to said photodetector.