KR970012372A - Dual Focus Optical Pickup - 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 disk player, and more particularly, to a dual focus optical pickup of a digital disk player which selectively reads information recorded on a disk having a thickness of 1.2 mm and a disk having a thickness of 0.6 mm. It relates to a pickup device.

To this end, a permanent magnet is installed inside the yoke plate, and is disposed between the holder in which the objective lens is placed and the permanent magnet to move the holder up, down, left, and right to provide focusing coils and tracking coils for focusing and tracking adjustment. In an optical pickup apparatus, a first and a second objective lens are installed at predetermined positions at an upper portion of the holder to focus a laser beam on a disk, and a predetermined distance is provided below the first and second objective lens. First and second beam splits each having a predetermined inclined surface and a predetermined reflectance and transmittance, respectively, are provided at one side of the first and second beam splits at predetermined intervals to issue a laser beam having a predetermined wavelength. First and second laser diodes, the first and second beam splits are respectively provided at predetermined intervals below the first to generate a focus error by the knife edge function The second detector is a lens, said first and respectively installed with a predetermined interval on the lower side of the second lens hayeoseo detector having a first and a second photodetector for detecting a focus, tracking.

Description

Dual Focus Optical Pickup

Since this is an open matter, no full text was included.

5 is a block diagram of a dual focus optical pickup apparatus according to the present invention.

Claims (4)

Permanent magnets 71a and 72b are provided inside the yoke plate 70, and are disposed between the holder 74 where the objective lens is placed and the permanent magnets 71a and 72b to raise and lower the holder 74. In an optical pickup apparatus having focusing coils 73a, 73b and tracking coils 72a, 72b which move to the left and right to perform focusing and tracking adjustment, an appropriate interval at an upper predetermined position of the holder 74 is provided. The first and second objective lenses 75 and 76 and the first and second objective lenses 75 and 76, which are installed at a predetermined distance and focus the laser beam on the disk, respectively. Predetermined on one side of the first and second beam splits 79 and 80 and the first and second beam splits 79 and 80 having an optional reflectance and transmittance Spaced below the first and second laser diodes 77 and 78 and the first and second beam splits 79 and 80 which are respectively provided at intervals to generate laser beams of a predetermined wavelength. The first and second detector lenses 81 and 82 and the first and second detector lenses 81 and 82 are respectively provided at predetermined intervals to generate focus errors by the knife edge function. And a first and second photodetectors (83, 84) for detecting focus and tracking. The dual focus optical pickup apparatus of claim 1, wherein the first and second objective lenses (75, 76) are arranged symmetrically with each other at a predetermined interval on the holder (74). According to claim 1, wherein the first and second objective lenses (75, 76), the two first and second objective lenses (75, 76) on the upper side of the holder 74 is a predetermined interval. Dual focus optical pickup device characterized in that arranged side by side. The dual focus light according to claim 1, wherein the first and second beam splits (79, 80) are provided so that the inclined surfaces (79a) (80a) for reflecting and transmitting the laser beam are symmetric with each other. Pickup device. ※ Note: The disclosure is based on the initial application.