Samsung Electronics Co., Ltd.

No-jun Kwak

Jong-ryull Kim

Pyong-yong Seong

Chul-ho Jeon

Ki-bok Kim

Bong-hwoan Choi

Ki-bong Yun

An optical pickup includes a laser light source, an objective lens which focuses light emitted from the laser light source on an optical information storing medium, an optical path changer which changes a proceeding path of the light emitted from the laser light source, a polarization changer which changes the polarization of an incident light to make the polarization of light reflected by the optical information storing medium and reentering the laser light source different from that of the light emitted from the laser light source, so that noise generated due to interference by the light reflected by the optical information storing medium and reentering the laser light source is reduced, and a photodetector which receives incident light reflected by the optical information storing medium and sequentially passing through the objective lens and the optical path changer and detects an information signal and/or an error signal.

Optical pickup reducing noise and polarization changer

A method and an apparatus for identifying the type of an optical recording medium are provided. The method includes detecting a surface reflected signal Sand a writable-surface reflected signal Sof an optical recording medium while performing a focus search using a first optical system, counting a time difference DTbetween a high peak and a low peak of the surface reflected signal S, counting a time difference DTbetween the high peak of the surface reflected signal and a high peak of the writable-surface reflected signal S, obtaining DT by substituting DTand DTinto the following equation: and comparing DT with a reference time T, and driving the first optical system if DT is greater than T and driving a second optical system if DT is not greater than T.

Method and apparatus for identifying the type of optical recording medium

Growing community of inventors

Suwon-si, South Korea

No-jun Kwak