公开(公告)号：US12014761B2

公开(公告)日：2024-06-18

申请号：US18030226

申请日：2021-10-06

Applicant: Panasonic Intellectual Property Management Co., Ltd.

Inventor： Yuuichi Kuze ,  Masatoshi Yajima ,  Shinichi Konishi ,  Akihiko Nishioka

IPC: G11B7/0037 ,  G01N21/95 ,  G11B7/127 ,  G11B7/00

CPC classification number: G11B7/00375 ,  G01N21/9506 ,  G11B7/127 ,  G11B2007/0006

Abstract: An optical disc device includes: an optical pickup including a first laser light source that emits laser light, an objective lens that focuses the laser light emitted from the first laser light source onto an optical disc, and a light receiving element that receives reflected light from the optical disc, and performs photoelectric conversion on the reflected light received to output a received-light signal; an FS signal generator that generates an FS signal indicating the light amount of the reflected light from the optical disc, based on the received-light signal from the light receiving element; and a dirt determiner that determines that dirt is present in the optical pickup, when the peak level of the FS signal is less than a dirt determination threshold, and controls the light receiving element to increase the peak level of the received-light signal from the light receiving element.