Patent ID: 6396638
Filing Date: 2002-05-28
Classification: B82Y,G11B

Abstract:
An optical pickup device comprising:a light source for generating light; an objective lens for focusing incident light to form a light spot on a recording medium and having an incidence region of a predetermined size; a tracking mirror disposed on the light path between the light source and the objective lens, for reflecting incident light emitted from the light source so that the light spot traces proper track positions of the recording medium; a lens unit including at least two lenses which allow the light reflected from the tracking mirror to be incident on the incidence region of the objective lens; and a photo detecting unit for receiving light reflected from the recording medium and having passed through the objective lens, wherein the objective lens comprises a first transmission portion forming the incidence region, for spreading incident light, a first reflection portion spaced a predetermined distance apart from the first transmission portion, for reflecting divergent incident light incident from the first transmission portion, a second reflection portion provided around the first transmission portion, for further reflecting the light reflected from the first reflection portion and focusing the same, and a second transmission portion provided at an interior or exterior side of the first reflection portion, for transmitting incident light to be focused on the recording medium.