Patent application number | Description | Published |
20090103422 | OPTICAL RECORDING HEAD DEVICE, OPTICAL RECORDING APPARATUS, AND RECORDING METHOD - According to one embodiment, an optical recording head device includes a light source which outputs such a relaxation oscillation optical pulse that a full width at half maximum of a single pulse is 820 ps or less, a driving unit for driving the light source, an objective lens which converges emission light from the light source on a recording layer of a recording medium, and captures reflective light which is reflected by the recording layer of the recording medium, a distribution unit, placed between the light source and the objective lens, for distributing incident light, and a photodetection unit for receiving via the distribution unit the reflective light which is reflected by the recording layer of the recording medium, wherein a resonator length of the light source is 6560 μm or less. | 04-23-2009 |
20090109809 | LASER DRIVE DEVICE AND INFORMATION RECORDING/REPRODUCING APPARATUS USING THE DEVICE - According to one embodiment, a laser drive circuit includes a photodetector which receives part of laser light emitted from a laser element to a recording medium independently of reflection laser light reflected by the recording medium, and outputs an output corresponding to the strength thereof, an integration circuit which integrates the output from the photodetector for a predetermined time, and a setting circuit which sets the intensity of a laser drive current supplied to the laser element on the basis of the output from the integration circuit. | 04-30-2009 |
20090109815 | OPTICAL DISC DEVICE AND OPTICAL DISC PROCESSING METHOD - According to one embodiment, an optical disc device includes a light source portion which applies laser light to an optical disc, a drive portion which supplies a drive current to the light source portion so as to cause the light source portion to apply laser light of light pulses having relaxation oscillation, and a controller which controls the drive portion to supply a drive current so as to cause the light source portion to emit laser light of (n−1)×N (N is an integral number) light pulses having relaxation oscillation with respect to a mark with recording mark length nT (n: integral number, T: channel clock) to be recorded on the optical disc. | 04-30-2009 |
20090109816 | OPTICAL DISC APPARATUS AND OPTICAL DISC PROCESSING METHOD - According to one embodiment, a calibration section controls an LD driving section so as to carry out test writing on a recording layer of an optical disc using a light pulse having relaxation oscillation, irradiates the test-written area with a reproduction laser beam so as to detect reflected light, and determine write strategy based on the detected result. A recording process is executed on the optical disc by using the light pulse having relaxation oscillation based on the write strategy determined by the calibration section. | 04-30-2009 |
20090141760 | DRIVE CONTROL APPARATUS AND DRIVE CONTROL METHOD OF SEMICONDUCTOR LASER - According to one embodiment, a drive control apparatus of a semiconductor laser includes a driving circuit which drives the semiconductor laser by applying pulses transiting from bias current to peak current to the semiconductor laser as laser driving current that causes relaxation oscillation of emission light intensity of the semiconductor laser, and a control circuit which controls the bias current such that the bias current has a predetermined ratio limiting fluctuation of a leading peak value of the relaxation oscillation occurring for each application of pulses relative to threshold current of the semiconductor laser. The control circuit changes the bias current to maintain the predetermined ratio relative to fluctuation of the threshold current. | 06-04-2009 |
20090196138 | INFORMATION RECORDING APPARATUS AND CONTROL METHOD THEREOF - According to one embodiment, in one embodiment of the invention, a laser drive circuit is provided with a first current source, a second drive current source, and a third current source. The control section selectively obtains a plurality of laser light use mode of controlling the from first to third current sources to use pulse laser light accompanying relaxation oscillation, and a complex laser light use mode of using laser light where laser pulses are combined, whose starting end has an abrupt impulse change portion caused by relaxation oscillation and whose intermediate section is a flat portion with a fixed intensity. | 08-06-2009 |
20090196142 | INFORMATION RECORDING MEDIUM, INFORMATION RECORDING METHOD, AND INFORMATION RECORDING AND REPRODUCING APPARATUS - According to one embodiment, in an information recording medium for which a phase change material is used and in which information is recorded on, reproduced from, and erased from a recording layer by light irradiation, a recrystallization width WR at a periphery of an amorphous recording mark formed on the recording layer by light irradiation, and a recording mark width WA and a track pitch TP satisfy 1.008-06-2009 | |
20090196148 | MASTER RECORDING APPARATUS AND MASTER RECORDING METHOD - According to one embodiment, the invention provides a master recording apparatus and method which can form a pit having a symmetrical pit shape with excellent reproducibility. An embodiment of the invention is a master recording apparatus where a resist film on a master for an optical disk is irradiated with irradiation light from a semiconductor laser to record information on the resist film, where the resist film is formed as an inorganic resist film, and means for outputting the irradiation light from the semiconductor laser as a short pulse laser with a pulse width between 200 ps and 1 ns is provided. | 08-06-2009 |
20090196157 | INFORMATION RECORDING MEDIUM - According to one embodiment, an information recording medium includes a substrate, a phase-change recording layer formed on the substrate, and a reflecting layer formed on the phase-change recording layer. The phase-change recording layer contains tellurium and antimony or bismuth as main components, has a crystallization rate of 2 to 10 ns, and forms a recording mark by changing its crystal state when irradiated with a light pulse having a half-width of 200 ps to 1 ns. | 08-06-2009 |
20090268580 | MASTER RECORDING APPARATUS, MASTER RECORDING METHOD, MASTER FOR STAMPER CONTAINING HEAT-SENSITIVE RESIST MATERIAL, AND METHOD OF FORMING FILM OF HEAT-SENSITIVE - According to one embodiment, a pit having a shape wherein the shapes of the top of a recording mark (recording start position) and the end of the recording mark (recording end position) are symmetrical can be formed on a stamper master with high reproducibility. As a result, the noise level/jitter degree of the reproduction signal obtained by reproduction from an optical disc as a final product can be reduced, thereby manufacturing at low cost the optical disc from which a signal can be stably reproduced. | 10-29-2009 |
20130077459 | OPTICAL DISC AND RECORDING AND REPRODUCING APPARATUS AND METHOD - In a recording and reproducing apparatus, an optical disc is rotated in a rotating direction and an optical system focuses a laser beam on the optical disc to form a beam spot on the optical disc. The optical system is provided with a scanner which deflects the laser beam along a radial direction of the optical disc in such a manner that the beam spot follows a first scan trajectory along a first direction crossing the rotating direction and a second scan trajectory along a second direction different from the first direction. A first data track with a sequence of recording pits along the first scan trajectory is formed and arranged on the optical disc. | 03-28-2013 |