Focus and tracking error detection by using plus and minus first

Details Focus and tracking error detection by using plus and minus first Focus and tracking error detection by using plus and minus first

1996-01-23

1998-04-07

Epps, Georgia Y.

Dynamic information storage or retrieval

Specific detail of information handling portion of system

Radiation beam modification of or by storage medium

369 4437, 369109, 369110, 369112, 369120, G11B 700

Patent

active

057372969

ABSTRACT:
An optical head device includes a light source for emitting light; an optical system for focusing the light emitted by the light source onto an information medium to form a light spot; a photodetector including a plurality of light detection areas for receiving the light reflected by the information medium and for outputting photocurrents in accordance with the respective amount of the light received; a holographic optical element for diffracting the light reflected by the information medium and for directing the light to the photodetector; and a signal processing circuit section for obtaining a focusing error signal and a tracking error signal for controlling the light spot using the photocurrents. The signal processing circuit section obtains the focusing error signal from the photocurrents which are obtained in accordance with the amount of light of one of .+-.Nth-order diffracted beams, and obtains the tracking error signal from the photocurrents which are obtained in accordance with the amount of light of the other of the .+-.Nth-order diffracted beams.

REFERENCES:
patent: 5406543 (1995-04-01), Kobayashi et al.
patent: 5502707 (1996-03-01), Komma et al.

Affiliated with

Also associated with

Rating

Focus and tracking error detection by using plus and minus first does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Focus and tracking error detection by using plus and minus first, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Focus and tracking error detection by using plus and minus first will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-19991