Samsung Electronics Co., Ltd.

Chun-gi Kim

Eun-goo Kim

Pyong-yong Seong

Kyoung-hwan Park

Ji-hwan Lim

Ju-hyung Lee

Kun-soo Kim

Jong-koog Lee

Yong-jun Cho

Seung-man Han

Hyun-seob Choi

A method and apparatus for detecting a signal to determine on-track/off-track and/or a track cross direction, using a detection signal corresponding to a reflected main light beam and detection signals respectively corresponding to reflected first and second sub light beams, and an optical recording and/or reproducing apparatus using the same are provided. When detection signals respectively corresponding to one side portions, in a direction corresponding to a radial direction of the optical information storage medium, of the respective main light beam and first and second sub light beams are referred to as a first main signal, a first sub signal, and a second sub signal, respectively, the method and apparatus include obtaining a first operational signal, which is used to determine on-track/off-track and/or a track cross direction, by performing a subtraction on the combination of the first and second sub signals, and the first main signal.

Signal detection method and apparatus and optical recording and/or reproducing apparatus using the same

A compatible optical pickup, including first and second light sources for emitting lights with different wavelengths and first and second photodetectors for detecting an information signal and/or an error signal, and a method of detecting the amount of output light using the compatible optical pickup. The first and second photodetectors monitor the amount of light output from the second and first light sources respectively such that no extra front photodetectors are required. Thus, the number of optical component parts included in the optical pickup can be reduced, thereby lowering the manufacturing costs for the optical pickup. Also, there is no need to secure a space in a base where a front photodetector is to be installed, so the base is simplified. Thus, inferior moldings are reduced, and the durability of a mold can be prolonged.

Compatible optical pickup and light output amount detecting method performed in the compatible optical pickup

An optical pickup for a recording medium includes a light source, an objective lens, a main photodetector, and a front photodetector. The configuration of the optical pickup enables converging or diverging of light to be incident on a plate beam splitter so that light can be received at an effective light receiving region of a front photodetector without interference due to internal reflection occurring in the plate beam splitter. In the alternative, a wedge beam splitter in the optical pickup includes first and second mirror planes at a predetermined angle to transmit and reflect incident light at a predetermined ratio. In the optical pickup, an amount of light that is exactly proportional to an output power of the light source can be detected, where the output power of the light source can be accurately controlled, thereby improving a linearity of the output power of the light source.

Optical pickup and a wedge beam splitter

Growing community of inventors

Suwon-si, South Korea

Chun-gi Kim