Claims
- 1. An optical recording method for recording mark length-modulated information with a plurality of recording mark lengths by irradiating a recording medium with a light, the optical recording method comprising the steps of:when a time length of one recording mark is denoted nT (T is a reference clock period equal to or less than 25 ns, and n is a natural number equal to or more than 2), dividing the time length of the recording mark nT into η1T, α1T, β1T, α2T, β2T, . . . , αiT, βiT, . . . , αmT, βmT, η2T in that order (m is a pulse division number; Σhd i(αi+βi)+η1+η2=n; αi (1≦i≦m−1) is a real number larger than 0; βi (1≦i≦m−1) is a real number larger than 0; βm is a real number larger than or equal to 0; αi+βi (2≦i≦m−1) or βi−1+αi (2≦i≦m−1) is kept constant independently of said real number i; and η1 and η2 are real numbers between −2 and 2); radiating recording light with a recording power Pwi in a time duration of αiT (1≦i≦m); and radiating recording light with a bias power Pbi in a time duration of βiT(1≦i≦m−1), the bias power being Pbi<Pwi and Pbi<Pwi+1; wherein the pulse division number m is 2 or more for the time duration of at least one recording mark and meets n/m≧1.25 for the time length of all the recording marks, further wherein when the same pulse division number m is used on at least two recording marks with different n values, a difference mark length is formed by changing at least one of β1, βm−1, and βm.
- 2. An optical recording method according to claim 1, wherein αi+βi (2≦i≦m−1) or βi−1+αi (2≦i≦m−1) is 2 independently of said real number i.
- 3. An optical recording method according to claim 1, wherein αi is kept constant as a constant value αc where said is (2≦i≦m−1).
- 4. An optical recording method according to claim 1, wherein αi (2≦i≦m−1) is kept constant in the time length of the recording mark with having a pulse division number m being at least 3.
- 5. An optical recording method according to claim 1, wherein when performing a mark length modulation scheme recording on the same recording medium by using a plurality of linear velocities v while keeping v×T constant,for m equal to or greater than 2, (αi+βi) in 2≦i≦m−1 is kept constant independently of the linear velocity, Pw1, Pbi and Pe in each i are kept almost constant independently of the linear velocity, and αi (2≦i≦m) is decreased as the linear velocity lowers.
- 6. An optical recording method according to claim 1, wherein when performing a mark length modulation scheme recording on the same recording medium by using a plurality of linear velocities v while keeping v×T constant,for m equal to or greater than 2, (βi−1+αi) in 2≦i≦m are kept constant independently of the linear velocity, Pw1, Pb1 and Pe in each i are kept almost constant independently of the linear velocity, and αi (2≦i≦m) are decreased as the linear velocity lowers.
- 7. An optical recording according to claim 5 or 6, wherein αiT (2≦i≦m−1) is kept almost constant independently of the linear velocity.
- 8. An optical recording method according to claim 1, the phase change type optical recording medium having a recording layer made of MzGey(SbxTe1-x)1-y-z alloy (where 0≦z≦0.1, 0<y≦0.3, 0.8≦x; andM is at least one of In, Ga, Si, Sn, Pb Pd, Pt, Zn, Au, Ag, Zr, Hf, V, Nb, Ta, Cr, Co, Mo, Mn, Bi, O, N and S).
- 9. An optical information recording medium having a recording layer, containing excessive Sb in SbTe eutectic point, in which phase change is made reciprocally between a crystal state and amorphous state with optical characteristic being differed from each other by irradiation of an optical beam, wherein said crystal condition is defined as polycrystal made of a substantial single crystal phase of a hexagonal crystal.
- 10. An optical information recording medium according to claim 9, wherein said recording layer is made of MzGey(SbxTe1-x)1-y-z alloy (where 0≦z≦0.1 0<y≦0.3, 0.8≦x; andM is at least any one of In, Ga, Si, Sn, Pb, Pd, Pt, Zn, Au, Ag, Zr, Hf, V, Nb, Ta, Cr, Co, Mo, Mn, Bi, O, N and S).
- 11. An optical information recording medium according to claim 9 or 10, wherein said crystal state of said recording layer is defined as an unrecorded state and an erased state, while said amorphous state thereof is defined as a recorded state and an erased state, while said amorphous state thereof is defined as a recorded state so as to performed recording or erasing of information.
- 12. A method of manufacturing an optical information recording medium having a recording layer, containing excessive Sb in SbTe eutectic point, in which phase change is made recriprocally between a crystal state and amorphous state with optical characteristic being differed from each other by irradiation of an optical beam, whereinan initialization step is performed with another optical beam having an elliptical beam shape of which minor axis is 0.1-10 μm after forming at least said recording layer on a substrate, by scanning said another optical beam to the recording layer in a direction of said minor axis so as to make the recording layer in the crystal state, further wherein said scanning of said optical beam is performed in a speed in a range of 50-80% of a maximum usable linear velocity for over-writing of the recording layer.
Priority Claims (2)
Number |
Date |
Country |
Kind |
11-138067 |
May 1999 |
JP |
|
2000-076514 |
Mar 2000 |
JP |
|
Parent Case Info
This is a division of application Ser. No. 09/884,121 filed Jun. 20, 2001, now U.S. Pat. No. 6,411,579, which is a continuation application of International patent application No.PCT/JP00/03036, filed May 11, 2000.
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Continuations (1)
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Number |
Date |
Country |
Parent |
PCT/JP00/03036 |
May 2000 |
US |
Child |
09/884121 |
|
US |