US 20020136122A1
(19) United States
(12) Patent Application Publication (io) Pub. No.: US 2002/0136122 Al
Nakano (43) Pub. Date: Sep. 26,2002
(54) OPTICAL INFORMATION RECORD
MEDIUM, METHOD OF RECORDING
INFORMATION ON OPTICAL
INFORMATION RECORD MEDIUM, AND
INFORMATION RECORDING APPARATUS
(76) Inventor: Kazuhiko Nakano, Tokyo (JP)
Correspondence Address:
DICKSTEIN SHAPIRO MORIN & OSHINSKY
LLP
2101 L STREET NW
WASHINGTON, DC 20037-1526 (US)
In recording on a second or deeper information recording layer of an optical information record medium having a plurality of recording layers, power of a recording laser beam is appropriately controlled even when quantity of transmitting beam is changed depending on recording states of information recording layers positioned on the incidence side of the information recording layer in which information is to be recorded.
The optical information record medium is provided with recording power test areas respectively in the second and deeper information recording layers, separately from user data recording areas. Those recording power test areas are used for testing a recording power of the recording laser beam. Further, before recording on a user data recording area in a second or deeper information recording layer, the recording power test area in the recording layer in question is used to test the recording power, to obtain a reference power and a level of a return beam at that time. Then, in recording on an arbitrary location in the user data area of the recording layer in question, the optimum recording power for the mentioned arbitrary location is calculated using a level of a return beam detected in recording on a location in the neighborhood of the mentioned arbitrary location, the reference power obtained in the test of the recording power, and the level of the return beam obtained at that time. The power of the recording laser beam is controlled such that recording on the mentioned arbitrary location is performed with that optimum recording power.
