| US 7,532,555 B2 | ||
| Phase-change recording layer optical recording method | ||
| Masaaki Mizuno, Tokyo (Japan); Hiroyuki Hoshino, Tokyo (Japan); Takashi Ohno, Tokyo (Japan); and Michikazu Horie, Tokyo (Japan) | ||
| Assigned to Mitsubishi Kagaku Media Co., Ltd., Tokyo (Japan) | ||
| Filed on Jun. 13, 2005, as Appl. No. 11/151,491. | ||
| Application 11/151491 is a continuation of application No. PCT/JP03/15984, filed on Dec. 12, 2003. | ||
| Claims priority of application No. 2002-363145 (JP), filed on Dec. 13, 2002. | ||
| Prior Publication US 2005/0276169 A1, Dec. 15, 2005 | ||
| Int. Cl. G11B 7/00 (2006.01); G11B 5/09 (2006.01) | ||
| U.S. Cl. 369—59.11 [369/116; 369/47.5; 369/275.1; 369/13.35] | 8 Claims |
| 1. An optical recording method in which a crystalline state of a phase-change recording layer of a rewritable optical recording
medium having said phase-change recording layer is used as unrecorded/erased state, and information is recorded by forming
recording marks in an amorphous state with various time lengths nT (where T is a reference clock period, and n is an integer
not less than 2), characterized in that:
(M-1) when a recording velocity is within a range of recording velocities at which recorded information in said rewritable
optical recording medium can be rewritten,
a plurality of recording marks with the time length of nT are formed;
dividing said time length nT into η1T, α1T, β1T, α2T, β2T, . . . , αiT, βiT, . . . , αmT, βmT and η2T (where m is a pulse dividing number, i is an integer not less than 1 and not larger than m, Σi(αi+βi)+η1+η2=n, αi(1≤i≤m) is a real number larger than 0, βi(1≤i≤m−1) is a real number larger than 0, βm is a real number not less than 0, and η1 and η2 are real numbers not less than −2 and not larger than 2) in this order, where said pulse dividing number m for at least one
time length of the recording marks is not less than 2, and the every time length of recording marks satisfies n/m≧1.25;
applying a recording beam having a recording power Pwi(1≤i≤m) during a time period of αiT;
applying a recording beam having a bias power Pbi(1≤i≤m, Pbi<Pwi, Pbi<Pwi+1) during a time period of βiT;
applying a recording beam having an erasing power Pe (Pe is a value not less than any values of m Pbi's where 1≤i≤m, and is a value smaller than any values of m Pwi's where 1≤i≤m) on the spaces between said plural recording marks; and
(M-2) when said recording velocity is higher than the recording velocity at which recorded information in said rewritable
optical recording medium can be rewritten, and when the phase-change recording layer is beforehand crystallized,
a recording mark with a time length nT is formed with one block pulse in which a recording beam with a recording power PwH
and a recording beam with a bias power PbH are applied.
|