US7782744B2
Active / In Force
US
⏱️ 2.3 years remaining
Systems and methods for forming a master disk utilizing variation in an applied signal power for forming uniform pits
Assignee: Sony Corp
•
Filing: 2009-01-30
•
Granted: 2010-08-24
•
Expires: 2029-01-30
Abstract
Abstract A recording method whereby an inorganic resist made of an incomplete oxide of a transition metal is formed as a film onto a substrate and a latent image corresponding to pits is formed onto the inorganic resist by exposure. The exposure is performed by a laser beam whose intensity has been modulated by a pulse signal whose pulse height decreases in a rear portion in a length direction of the pit, thereby forming a format of a track pitch smaller than a recording beam diameter (track pitch/exposure beam diameter=0.333 to 0.833).
Inventors
- 👤 Sohmei Endoh
- 👤 Noriyuki Saito
- 👤 Takahiro Igari
- 👤 Takeshi Gouko
- 👤 Shinji Minegishi
- 👤 Eijiro Kikuno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:08
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/004; G11B7/0045; G11B7/00456; G11B7/24; G11B7/241; G11B7/242; G11B7/243; G11B7/26; G11B7/261; G11B2007/24302; G11B2007/24306; G11B2007/24318; G11B2007/2432; G11B7/252; G11B7/253; Y; Y10; Y10T; Y10T428/00; Y10T428/21
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
163 words
A recording method whereby an inorganic resist made of an incomplete oxide of a transition metal is formed as a film onto a substrate and a latent image corresponding to pits is formed onto said inorganic resist by exposure, wherein the exposure is performed by a laser beam whose intensity has been modulated by a pulse signal whose pulse height is first asserted at first maximum height and then asserted one or more times at intermediate non-zero heights lower than the first maximum height in a rear portion in a length direction of the pit, wherein as a result of the exposure, a track pitch smaller than a recording beam diameter is formed in the recording medium, and wherein a ratio of track pitch/exposure beam diameter is in the range of 0.333 to 0.833, and further wherein for each pit, a first pulse signal that is generated for defining the pit is a highest signal level for all pulse signals defining the pit.
Claim 2
Dependent Claim
163 words
A recording method whereby an inorganic resist made of an incomplete oxide of a transition metal is formed as a film onto a substrate and a latent image corresponding to pits is formed onto said inorganic resist by exposure, wherein the exposure is performed by a laser beam whose intensity has been modulated by a pulse signal whose pulse height is first asserted at first maximum height and then asserted one or more times at intermediate non-zero heights lower than the first maximum height in a rear portion in a length direction of the pit, wherein as a result of the exposure, a track pitch smaller than a recording beam diameter is formed in the recording medium, and wherein a ratio of track pitch/exposure beam diameter is in the range of 0.333 to 0.833, and further wherein for each pit, a first pulse signal that is generated for defining the pit is a highest signal level for all pulse signals defining the pit.
Claim 3
Dependent Claim
162 words
A recording system whereby an inorganic resist made of an incomplete oxide of a transition metal is formed as a film onto a substrate and a latent image corresponding to pits is formed onto said inorganic resist by exposure, means for performing exposure by a laser beam whose intensity has been modulated by a pulse signal whose pulse height is first asserted at first maximum height and then asserted one or more times at intermediate non-zero heights lower than the first maximum height in a rear portion in a length direction of the pit, wherein as a result of the exposure, a track pitch smaller than a recording beam diameter is formed in the recording medium, and wherein a ratio of track pitch/exposure beam diameter is in the range of 0.333 to 0.833, and further wherein for each pit, a first pulse signal that is generated for defining the pit is a highest signal level for all pulse signals defining the pit.
Claim 4
Dependent Claim
162 words
A recording system whereby an inorganic resist made of an incomplete oxide of a transition metal is formed as a film onto a substrate and a latent image corresponding to pits is formed onto said inorganic resist by exposure, means for performing exposure by a laser beam whose intensity has been modulated by a pulse signal whose pulse height is first asserted at first maximum height and then asserted one or more times at intermediate non-zero heights lower than the first maximum height in a rear portion in a length direction of the pit, wherein as a result of the exposure, a track pitch smaller than a recording beam diameter is formed in the recording medium, and wherein a ratio of track pitch/exposure beam diameter is in the range of 0.333 to 0.833, and further wherein for each pit, a first pulse signal that is generated for defining the pit is a highest signal level for all pulse signals defining the pit.
References Cited (Backward Citations)
US5430696A
Cited
US5459701A
Cited
US5331612A
Cited
US5457666A
Cited
US5905695A
Cited
US5742566A
Cited
US6243326B1
Cited
US5757735A
Cited
US5825742A
Cited
US6287660B1
Cited
US6925040B1
Cited
US6396792B1
Cited
US7197005B2
Cited
US7289412B2
Cited
JP2003315988A
Cited
JP2003346390A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2013-08-23 | 2014-02-22 | 2014-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2017-08-23 | 2018-02-22 | 2018-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2021-08-23 | 2022-02-22 | 2022-08-24 | $7700.00 | Window Closed / Lapsed |