Patent Number: 7,272,103

Title: Laser power monitor device, optical pickup including the same, and optical recording and/or reproducing apparatus including the same

Abstract: In order to improve the frequency characteristic of a laser power monitor device and the precision of laser power control when low-speed recording is performed, there is provided a laser power monitor device for an optical recording and/or reproducing apparatus, the laser power monitor device including a photo diode unit to receive part of a light emitted from a laser diode and output a current proportional to optical power, and a monitor circuit to receive the current output from the photo diode unit, convert the received current into a voltage, and outputs the voltage to an automatic laser power control circuit, and the photo diode unit includes a plurality of photo diodes connected to the monitor circuit to supply current to the monitor circuit. The laser power monitor device further includes a switch unit, wherein the switch unit is located between the photo diode unit and the monitor circuit to receive a signal on a current recording speed and switch so that the number of photo diodes supplying current to the monitor circuit is reduced as the recording speed is increased.

Inventors: Kwon; Sung-du (Seoul, KR), Lee; Jun-hyuk (Suwon-si, KR), Seong; Pyong-yong (Seoul, KR), Bang; Hyun-cheal (Suwon-si, KR), Lee; Jong-koog (Seoul, KR), Cho; Yong-jun (Suwon-si, KR)

Assignee: Samsung Electronics Co., Ltd.

International Classification: G11B 7/00 (20060101)

Expiration Date: 2019-09-18 0:00:00