KR960042558A - Dual Focus Optical Pickup in Digital Video Disc Player - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dual focus optical pickup device of a digital video disc player. In particular, the present invention relates to a conventional audio disc having a thickness of 1,2 mm and a digital video disc having a thickness of 0.6 mm to selectively read information. A dual focus optical pickup device of a digital video disc player.

To do this, the dual focus of a digital video disc player includes a diffraction grating that separates the beam generated from the laser diode into 0th order and ± 1st order light, and a dual focus lens that focuses the separated light on the video and audio discs. An optical pickup apparatus, comprising: a first objective lens disposed at a predetermined distance from the diffraction grating and refracted at an appropriate ratio according to incident light to transmit the light; Splitting into a beam split, coated on one side of the beam split, a polarizing film passing P waves and reflecting S waves, using optical information recorded on one side of the beam split and recorded on the reflected disk Integrally forming a micro Fresnel lens for generating astigmatism to detect a focus error, and the dual focus A wavelength conversion unit disposed between the lens and the beam split to convert optical information of the P wave recorded on the disc into the S wave, and an optical detector for converting an astigmatism beam generated from the micro Fresnel lens into an electrical signal. .

Description

Dual Focus Optical Pickup in Digital Video Disc Player

As this is a public information case, the full text was not included.

2 is a block diagram of a dual focus optical pickup device of a digital video disc player according to the present invention.

Claims (1)

Rotating lattice 52 that separates the beam generated from the laser diode 51 into 0th order and ± 1st order light, and a dual focus lens that focuses the separated light on the video and audio discs 58 and 59. A dual focus optical pickup device of a digital video disc player comprising: a first objective lens (63) installed at a predetermined interval with the diffraction grating (52) and transmitted by refracting at an appropriate ratio according to incident light; Polarized light is installed on the upper part of the objective lens 63 to separate incident light into reflected light and transmitted light of a constant ratio, and is coated on one side of the beam split 53 and the beam split 53 to pass P waves and reflect S waves. The film 64 and the micro Fresnel lens 62 are formed on one side of the beam split 53 to generate astigmatism for detecting a focus error using optical information recorded on the reflected disk. brother And a wavelength converting section 65 provided between the dual focus lens 55 and the beam split 53 for converting optical information of the P wave recorded on the disk into the S wave, the beam split 53 and A dual focus optical pickup device for a digital video disc player, comprising a photo detector (61) provided at predetermined intervals to convert astigmatism beams generated from the micro Fresnel lens (62) into electrical signals. ※ Note: The disclosure is based on the initial application.