Classifications

• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
  • G11B19/20—Driving; Starting; Stopping; Control thereof
  • G11B19/24—Arrangements for providing constant relative speed between record carrier and head
  • G11B19/247—Arrangements for providing constant relative speed between record carrier and head using electrical means
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
  • G11B19/20—Driving; Starting; Stopping; Control thereof
  • G11B19/24—Arrangements for providing constant relative speed between record carrier and head

Definitions

• the invention relates to a method for shortening the on-time of an optical recording and / or reproducing device, in which a light beam is focused on a rotating disk in order to read the data on the disk.
• Such a playback device is, for example, a CD player whose optical scanning device focuses a light beam onto the rotating recording medium, the compact disc, in order to be able to scan the data recorded on spiral data tracks.
• a CD player is a so-called CLV system, the abbreviation for constant linear velocity, in which the data is read at a constant web speed.
• the speed of the disk is therefore based on a synchronizing signal contained in the data signal on the data track being scanned regulated speed. If the data tracks of the disk are read from the inside out, the speed of the disk is reduced as the scanner moves from the center of the disk to the edge of the disk.
• the speed of the plate can only be regulated to the target speed when the data signal is available, the light beam must first be focused on the plate. Only after focusing is the optical scanning device delivering the data signal and the synchronizing signal, which is now used to regulate the speed of the disk. Before you can start reading the data - with a CD player playing the disc - the light beam must first be focused on the disc and then the speed of the disc must be adjusted to the target speed.
• the invention achieves this object in that when the device is switched on, the current position of the optical scanning device is detected, the speed of the disk is regulated to the speed corresponding to the current position of the optical scanning device, during which the light beam is focused on the disk, and that as soon as the light beam is focused on the plate, the speed of the plate is regulated by means of a synchronous signal read from the plate.
• the invention is based on the knowledge that in a CLV system a specific speed of the disk is prescribed for each position of the optical scanning device. If the position of the scanning device is determined when the CD player is switched on, for example by means of a position detector, the speed of the disk can be regulated immediately to the value corresponding to the current position of the scanning device without having to wait for focusing. While the speed of the plate is now increased from the Mull value to the target speed, the light beam is focused on the plate at the same time.
• a synchronous signal recorded on the disk is used to regulate the disk speed.
• a first embodiment of the invention provides that if the focus is lost during game operation, e.g. as a result of a shock, the speed set at the moment the focus is lost is maintained until the focus is found again. This measure has the advantage that after finding the focus again, the difference between the retained speed and the new target speed is almost zero.
• the instantaneous position of the scanner is maintained if the focus is lost.
• the speed of the disk set at the moment of a loss of focus and the position of the scanning device can be stored in order to determine how find the focus from the stored values to continue playing the data.
• All described embodiments of the invention have the advantage that if the focus is lost and the focus is found again during game operation, the speed of the disk is regulated to the target speed in the shortest possible time.
• the invention is suitable for optical recording and / or reproducing devices in which a light beam is focused on the recording medium, a rotating plate, in order to scan the data of the recording medium as is usual in a CLV system with constant web speed.
• Examples include CD players, video record players, DRAW disc players and magneto-optical devices.

Landscapes

• Moving Of The Head For Recording And Reproducing By Optical Means (AREA)
• Optical Recording Or Reproduction (AREA)
• Rotational Drive Of Disk (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6406998

Family Applications (1)

Country Status (5)

Citations (4)

• 1990
  • 1990-05-23 DE DE19904016552 patent/DE4016552A1/de not_active Withdrawn
• 1991
  • 1991-05-14 EP EP19910909199 patent/EP0530234A1/de not_active Withdrawn
  • 1991-05-14 HU HU329692A patent/HUT64429A/hu unknown
  • 1991-05-14 JP JP91508941A patent/JPH05506532A/ja active Pending
  • 1991-05-14 WO PCT/EP1991/000893 patent/WO1991018392A1/de not_active Application Discontinuation

Patent Citations (4)

Non-Patent Citations (1)

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