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:
Apr. 28, 2009
Filed:
Jun. 02, 2003
Tatsuya Kato, Tokyo, JP;
Hideki Hirata, Tokyo, JP;
Tatsuya Kato, Tokyo, JP;
Hideki Hirata, Tokyo, JP;
TDk Corporation, Tokyo, JP;
Abstract
It is an object of the present invention to provide a method for recording data in an optical recording medium which can record data in a write-once type optical recording medium at a high linear recording velocity using a laser beam having a low recording power. The method for recording data in an optical recording medium according to the present invention is constituted so that when data are to be recorded in an optical recording medium including a substrate, a first recording layer and a second recording layer by projecting a laser beam whose power is modulated in accordance with a pulse train pattern including pulses whose levels are set to levels corresponding to a recording power Pw and a bottom power Pb onto the optical recording medium and forming a recording mark at a predetermined region of the first recording layer and the second recording layer, as a linear recording velocity increases, the power of the laser beam is modulated using a pulse train pattern including a smaller number of pulses whose level is set to a level to the recording power Pw, thereby forming a recording mark. According to the present invention, since the power of a laser beam is modulated using a pulse train pattern including a smaller number of pulses whose level is set to a level to the recording power Pw as a linear recording velocity increases, it is possible to record data in an optical recording medium using a laser beam having a low recording power even when a linear recording velocity is high and on the other hand, it is possible to prevent cross-talk of data from increasing even when a linear recording velocity is low. Therefore, it is possible to employ a semiconductor laser having a relatively low output even when data are recorded at a high linear recording velocity.