Creative Technology Corporation

Hitachi Zosen Corporation

Shigeki Okazaki

Yam Fei Lian

Yew Teng Too

Bin Chye Lim

Too Yew Teng

Choo Poo Dee

Hironaka Tanaka

Harunobu Nakaguchi

A device for detecting a crack in an optical disc including a transmitter to propagate an optical signal through the optical disc and a receiver to detect the propagated signal. From the pattern generated from the received signal, a microcontroller makes an analysis to determine if a crack is present on the optical disc. The method may be incorporated into a conventional disc drive as a new crack detection mechanism.

Method and system for detecting cracks in optical discs

In a CD drive , a tracking subsystem comprising tracking detector , a control processor and tracking actuator assembly , is coupled to photodiodes A-F, to have the lens assembly track a data track on a disc . A vibration detector subsystem comprising a vibration detector , the control processor , and the speed setting function , is also coupled to photodiodes A-F, and the vibration detector subsystem disables the tracking subsystem and detects vibration of the lens assembly at a resonant speed.

Method for detecting vibration in a disc drive and apparatus therefor

Growing community of inventors

Saitama, Japan

Shigeki Okazaki