Dynamic information storage or retrieval – With servo positioning of transducer assembly over track... – Optical servo system
Patent
1990-07-30
1992-09-08
Envall, Jr., Roy N.
Dynamic information storage or retrieval
With servo positioning of transducer assembly over track...
Optical servo system
369 4442, 369 4411, G11B 713
Patent
active
051464454
ABSTRACT:
An optical head equipped with a tracking error detector to obtain a tracking error signal for tracking servo. The detector includes a photodetector having a light-detecting region on which a light spot with a predetermined diameter is formed by a reflected light beam from a recording medium. The region is divided by a first division line into two which are further divided by second and third division lines so as to form first to fourth subregions, the first and second subregions being adjacent to each other with the first division line being interposed therebetween, the third subregion being adjacent to the first subregion, and the fourth subregion being adjacent to the second subregion. The separation between the second and third division lines is determined so that the sum of the light receiving quantities of the first and fourth subregions is substantially equal to the sum of the light receiving quantities of the second and third subregions when the objective lens is shifted from its neutral position. Electric signals produced in correspondance with the light receiving quantities are supplied to a differential amplifier to take a difference between a sum signal of the signals due to the first and fourth subregions and a sum signal of the signals due to the second and third subregions.
REFERENCES:
patent: 4051527 (1977-09-01), Braat
patent: 4926036 (1990-05-01), Maeda
patent: 4998235 (1991-03-01), Ishibashi et al.
Patent Abstracts of Japan, vol. 10, No. 147(P-460)(2204) May 29, 1986, & JP-A-60 263344 (Yokokawa Hokushin Denki K.K.) Dec. 26, 1985, * the whole abstract *.
Patent Abstracts of Japan, vol. 12, No. 451(P-791)(3298) Nov. 28, 1988, & JP-A-63 175233 (Canon Inc) Jul. 19, 1988, * the whole abstract *.
Aikoh Hideki
Kikuchi Noboru
Nakamura Tohru
Shinoda Masayuki
Envall Jr. Roy N.
Huber Paul W.
Matsushita Electric - Industrial Co., Ltd.
LandOfFree
Optical head with tracking error detecting system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Optical head with tracking error detecting system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical head with tracking error detecting system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-139705