Information recording method and apparatus with suppressed mark edge jitters

• US 6,236,635 B1
• Filed: 09/08/1998
• Issued: 05/22/2001
• Est. Priority Date: 09/09/1997
• Status: Expired due to Term

• Current Assignee: Hitachi Consumer Electronics Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Hirotsune, Akemi, Ushiyama, Junko, Terao, Motoyasu, Miyamoto, Makoto, Nishida, Tetsuya, Anzai, Yumiko, Andoo, Keikichi, Saga, Hideki, Ohtake, Masatoshi, Toda, Tsuyoshi
• Primary Examiner(s): EDUN, MUHAMMAD N
• Application Number:
  US09/149,051
• Time in Patent Office: 987 Days
• Field of Search: 369/47, 369/48, 369/49, 369/50, 369/54, 369/58, 369/56, 369/116, 369/13, 369/59
• US Class Current: 369/116
• CPC Class Codes: G11B 20/10009 Improvement or modification of read or write signals
• CPC Class Codes: G11B 20/1426 conversion to or from block codes or representations thereof
• CPC Class Codes: G11B 7/00454 involving phase-change effects
• CPC Class Codes: G11B 7/00557 involving phase-change media
• CPC Class Codes: G11B 7/006 Overwriting G11B7/0065 takes precedence
• CPC Class Codes: G11B 7/0062 Overwriting strategies, e.g. recording pulse sequences with erasing level used for phase-change media
• CPC Class Codes: G11B 7/126 Circuits, methods or arrangements for laser control or stabilisation

Abstract

A method for recording information is disclosed in which an information recording medium is irradiated with a recording energy beam power-modulated into at least a record power level and a record-ready power level lower than the record power level. When forming a mark portion of a predetermined length, the radiation energy of the energy beam is increased as compared with when forming a mark portion of a different length before or after the first pulse of an energy beam pulse train including at least a pulse for forming the mark portion. Also, only in the case where the energy beam is modulated by the power lower in power level than the record-ready power level after the last pulse of the energy beam pulse train including at least one pulse for forming a mark portion and the mark portion is followed by a space portion of a predetermined length, the particular radiation energy of low power level is reduced as compared with when the mark portion is followed by a space potion of a different length. The radiation energy is increased and/or decreased.

Claims

1. A method of recording information on a recording medium capable of being placed in a first state with a light beam at a second power level and in a second state with a light beam at a third power level higher than said second power level, by overwriting the information in the form of length and interval of a record mark portion in said second state, wherein:

when a record mark portion is formed with a plurality of light beam pulses each reaching said third power level, said plurality of light beam pulses are followed by an interval at a power level lower than said second power level; and

said power level of said interval lower than said second power level is higher than levels of intervals between said plurality of light beam pulses.

2. A method according to claim 1, wherein said power level of said interval lower than said second power level and higher than levels of intervals between said plurality of light beam pulses is changed according to a length of a space portion following said record mark portion.

3. A method according to claim 1, wherein when said plurality of light beam pulses contain three or more pulses, a power level of an interval between first and second pulses is higher than a power level of an interval between the second and third pulses.