Patent EP0446892A2 successfully refreshed from Google Patents.
EP0446892A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical data medium recording methods
Assignee: Panasonic Holdings Corp
•
Filing: 1991-03-13
•
Granted: —
•
Expires: 2011-03-13
Abstract
Abstract Before a signal is recorded to an optical disk (2), irradiations are made (B) with plural light irradiation conditions of variable irradiation power or pulse width, optical conditions of irradiated portions are detected (C) by detecting changes, in the reflectivity or transmissivity or errors, and the optimum irradiation conditions are determined by comparing (3) the detected results and the light irradiation conditions. In particular, by determining the optimum irradiation conditions in reference to the point where the change in reflectivity or transmissivity is greatest with respect to changes in the irradiation power, the light irradiation conditions can be determined in a short time.
Inventors
- 👤 Kenichi Nishiuchi
- 👤 Eiji Ohno
- 👤 Noboru Yamada
- 👤 Nobuo Akahira
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 18:38
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/12; G11B7/125; G11B7/126; G11B27/00; G11B27/36; G11B7/004; G11B7/0045; G11B7/00455; G11B7/24; G11B7/2407; G11B7/24085; G11B11/00; G11B11/10; G11B11/105; G11B11/10502; G11B11/1053; G11B11/10595
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
132 words
A method of recording to an optical data medium, said method recording a data signal by means of laser beam irradiation to a recording medium which changes reversibly between optically distinguishable states according to specific light irradiation conditions, and comprising: a process for accomplishing a light irradiation sequence combining plural different irradiation conditions before the data signal is recorded to the recording medium; a light detection process which detects the quantity of light reflected by or passing through the recording medium after the preceding light irradiation sequence; a process of measuring the signal obtained from the light detection process; a comparison process which compares the measured results; a process which determines the optimum irradiation conditions from the comparison result; and a process of recording the data signal using these optimized irradiation conditions.
Claim 2
Dependent Claim
64 words
A method of recording to an optical data medium according to Claim 1 wherein the irradiation beam is power modulated between at least two power levels, said power modulation is accomplished for one recording mark formed on the recording medium according to the data signal by means of a modulation pattern comprising plural pulse strings and selected from among at least two modulation patterns.
Claim 3
Dependent Claim
37 words
A method of recording to an optical data medium according to Claim 1 wherein the process which accomplishes the light irradiation sequence is performed at an area other than the data write area of the recording medium.
Claim 4
Dependent Claim
46 words
A method of recording to an optical data medium according to Claim 1 wherein the measuring process is accomplished by detecting the error quantity contained in the signal from the recording medium, and the optimum irradiation conditions are determined from the smallest number of detected errors.
Claim 5
Independent Claim
133 words
A method of recording to an optical data medium, said method recording a signal by means of laser beam irradiation to a recording medium which changes reversibly between optically distinguishable states according to specific light irradiation conditions, and comprising: a process for irradiating light at different power levels continuously for a predetermined period before recording the data signal to the recording medium; a process for measuring the changes in the quantity of reflected or transmitted light from or through the recording medium after light irradiation; a process for comparing the measured results of changes in the reflected or transmitted light quantity; a process for determining the optimum irradiation conditions of the recording medium by means of the comparison result; and a process for recording the data signal using the determined optimum irradiation conditions.
Claim 6
Dependent Claim
73 words
A method of recording to an optical data medium according to Claim 5 wherein as the method for comparing the reflected or transmitted light quantity, the irradiated power at which the change in the reflected or transmitted light quantity is greatest with respect to changes in the irradiated power is defined as the reference power level, and the optimum irradiation conditions are determined by multiplying this reference power level by a constant value.
Claim 7
Independent Claim
188 words
A method of recording to an optical data medium, said method recording a signal by means of laser beam irradiation to a recording medium which changes reversibly between optically distinguishable states according to specific light irradiation conditions, and comprising: a recording monitoring process which detects when the optical disk is changed, when the disk drive is started, when the ambient temperature of the operating environment changes more than a predetermined amount, when a predetermined period of time has passed after the irradiation conditions are set, or when more than a predetermined number of errors are detected in the read signal; a process for accomplishing a light irradiation sequence combining plural different irradiation conditions according to information from the monitoring process; a process for measuring the quantity of reflected or transmitted light from or through the recording medium after the above light irradiation sequence; a process of measuring the signal obtained from the light detection process; a comparison process which compares the measured results; a process which determines the optimum irradiation conditions from the comparison result; and a process of recording the data signal using these optimized irradiation conditions.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.