The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 22, 2007
Filed:
Dec. 11, 2002
Jeroen Arnoldus Leonardus Johannes Raaymakers, Eindhoven, NL;
Herman Petrus Van Der Kall, Eindhoven, NL;
Jeroen Arnoldus Leonardus Johannes Raaymakers, Eindhoven, NL;
Herman Petrus Van Der Kall, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
An optical playback or recording device is equipped with mass-unbalance detection means () for detecting unbalance on the record carrier (). Mass-unbalance causes vibration and sound in the optical device when the record carrier () is rotated at a relatively high speed. When mass-unbalance is detected, the speed may be reduced to reduce the vibration and sound in the optical device. The mass-unbalance detection means () performs the following steps to detect mass-unbalance: a) determining the maximum value Uof the actuator control signal (AS) at a rotational speed Ω; b) determining the maximum value Uof the actuator control signal (AS) at a rotational speed Ω; c) comparing Formula (I) with Formula (II). If these values are substantially equal, then the effect of mass-unbalance is small, otherwise the effect of mass-unbalance is too great and the speed may have to be reduced