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. 30, 1996
Filed:
Apr. 18, 1994
Kenji Tokumitsu, Odawara, JP;
Fumihiro Harigai, Odawara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In an optical information recording method and apparatus for performing the pre-write testing of test data for an optical recording medium connected to a host computer, an instruction for pre-write testing of test data inclusive of two predetermined continuous signals is received independently from a write command from the host computer. The pre-write testing of the test data is performed by supplying different laser driving currents for plural ones of pre-write testing areas of the optical recording medium to an optical information recording head in accordance with the pre-write testing instruction. The respective pre-write testing data are reproduced to determine a difference in an average voltage level between the two continuous signals of each test data. The laser driving current supplied for the pre-write testing of the test data indicative of the smallest value of the difference is set as a laser driving current which is to be supplied to the optical information recording head when the recording of user data is to be performed. A time interval until the next pre-write testing of test data is set in accordance with the set laser driving current. With the above construction, the pre-write testing can be eliminated at every write command requested from the host computer.