Patent US2323904A successfully refreshed from Google Patents.
Patent EP0933759A2 successfully refreshed from Google Patents.
EP0933759A2
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EP
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Data recording and optical disc drive
Assignee: Sony Corp
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Filing: 1999-01-21
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Granted: —
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Expires: 2019-01-21
Abstract
Abstract The data selector (59) provides the recording signal Data 1 as LD recording signal LD Data 1 and the output control signal Data 3' as LD recording signal LD Data 3, and fixes the LD recording signal LD Data 2 to H level. The S&H select circuit (58) supplies an inverted one of the NRZI signal to the enable terminal of the sample and hold circuit (53). The sample and hold circuit (53) samples an output of the bias power 1 part and supplies it as LD control signal LDC 2 to the APC circuit (55). Thus, the bias power 1 being a light power of the multi-pulse is sampled by the sample and hold circuit (53) and controlled by the APC circuit (55).
Inventors
- 👤 Isao Ichimura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 01:18
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/12; G11B7/125; G11B7/126; G11B7/004; G11B7/0045; G11B7/00454; G11B7/135; G11B7/1372
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
124 words
A phase-change optical disc drive in which a data of nT in pulse width is recorded
with a multi-pulse generated from a semiconductor laser, including a number (n-1) of pulses
and which shifts at a minimum of three, comprising: means for detecting a laser power of the semiconductor laser; and means for generating, when in a power control mode, an output control pulse larger in
pulse width than the multi-pulse to drive the semiconductor laser to generate a light pulse
based on the output control pulse, sampling and holding, based on the output control pulse,
the laser power detected by the detecting means, and controlling the laser power of the
semiconductor laser so that the sampled and held laser power has a predetermined value.
Claim 2
Dependent Claim
23 words
The phase-change optical disc drive as set forth in claim 1, wherein the
semiconductor laser generates NRZI pulse as the output control pulse.
Claim 3
Dependent Claim
36 words
The phase-change optical disc drive as set forth in claim 1, wherein the
semiconductor laser sets the leading edge and width of the output control pulse according to
the length of a mark to be recorded.
Claim 4
Dependent Claim
31 words
The phase-change optical disc drive as set forth in claim 1, wherein the
semiconductor laser generates the output control pulse at a different timing from the leading
edge of the multi-pulse.
Claim 5
Independent Claim
107 words
A method of recording a data of nT in pulse width with a multi-pulse generated
from a semiconductor laser, including a number (n-1) of pulses and which shifts at a
minimum of three levels, comprising the steps of: generating, when in a power control mode, an output control pulse larger in pulse
width than the multi-pulse; driving the semiconductor laser to generate a light pulse based on the output control
pulse; detecting a laser power of the semiconductor laser; sampling and holding the detected laser power; and controlling the laser power of the semiconductor laser so that the sampled and held
laser power has a predetermined value.
Claim 6
Dependent Claim
18 words
The method as set forth in claim 5, wherein NRZI pulse is generated as the output
control pulse.
Claim 7
Dependent Claim
32 words
The method as set forth in claim 5, wherein there is generated an output pulse
whose leading edge and width are set according to the length of a mark to be recorded.
Claim 8
Dependent Claim
26 words
The method as set forth in claim 5, wherein the output control pulse is generated at
a different timing from the leading edge of the multi-pulse.
References Cited (Backward Citations)
No citation records indexed.
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