Abstract: The illumination device capable of illuminating plural regions via a light diffusion element includes a laser light source that emits a laser beam, an optical scan unit capable of changing an optical path of the laser beam from the laser light source, an optical path adjustment element and a light diffusion element. On the optical path adjustment element, the laser beam from the optical scan unit is incident, an incidence position of the laser beam varies depending on the optical path determined by the optical scan unit; and an emission angle of the laser beam varies depending on the incidence position. The light diffusion element diffuses the laser beam and emits diffused light. On the light diffusion element, the laser beam from the optical path adjustment element is incident and an emission angle of the diffused light varies depending on an incidence angle of the laser beam.

Abstract: An exposure apparatus 10 is an exposure apparatus for forming a pattern by exposure by irradiating a set master 1 with laser light, comprising: an optical pickup 12 which is capable of adjusting the focus of laser light and a control unit 19 which adjusts the focus of laser light emitted from the optical pickup 12 using integrated surface profile data indicating the relative positional relationship between the surface of the master 1 and the optical pickup 12 according to at least one of the surface roughness of the master 1, the inclination of the master 1, and the decentering of the master 1.

Abstract: A storage device disclosed herein stores data on a storage media using interlaced magnetic recording (IMR) and it includes a storage controller configured to determine power levels applied to the power source such that power levels applied to heat various tracks can be different from each other. An implementation of the storage device determines the track density, linear densities and power levels for even and odd tracks in IMR HAMR for the storage media.

Abstract: A laser power applied to a recording head is changed for a plurality of iterations. Each iteration involves, via the recording head at each laser power, writing multiple adjacent tracks to a heat-assisted recording medium and determining a bit error rate for at least one of the adjacent tracks at each laser power. A first laser power is found that achieves a minimum bit error rate of the iterations. An operational value of laser power that is smaller than the first laser power is used during operational recording to reduce adjacent track interference.

Abstract: A mark having a length nT (n being an integer equal to or greater than 3 and T being a clock period) is formed by modulating irradiation laser power with three values of recording power Pw, erase power Pe, and bias power Pb (Pw>Pe>Pb). Constant strength periods (At) of the recording power Pw are set as AtT, A1T, . . . , and AmT and constant strength periods (B) of the bias power Pb are set as BtT, B1T, . . . , BmT, and CT (C=?1 to 3). The application of laser is divided into pulses in order of AtT, BtT, A1T, B1T, . . . , AmT, BmT, and CT (m=(n?k)/2, k=3 (if n is an odd number), or k=4 (if n is an even number)). (Here, the constant strength period of the recording power Pw for n=3, n=4, n?5 (odd number), and n?6 (even number) is set as At3, At4, Atod, and Atev, the constant strength period of the bias power Pb for n=3, n=4, n?5 (odd number), and n?6 (even number) is set as Bt3, Bt4, Btod, and Btev, and then, At3+Bt3=Atod+Btod=Am+Bm=2T and At4+Bt4=Atev+Btev=3T).

Abstract: In an optical information storage medium reproduction apparatus reproducing an optical information storage medium including a plurality of information recording layers each including a recording mark having a length shorter than an optical system resolution limit, reproduction laser power reading an information recording layer closest to a reproduction-laser-incident surface of the optical information storage medium is set to be lower than reproduction laser power reading an information recording layer farthest from the reproduction-laser-incident surface but not lower than minimum reproduction laser power that satisfies a reproduction signal characteristic that the optical information storage medium reproduction apparatus requires.

Abstract: An optical disc device uses an optical disc (6) capable of super-resolution reproduction, and includes a semiconductor laser (1), a laser driving circuit (21) that supplies a driving current to the semiconductor laser, a light receiving element (8) that detects return light from the optical disc (6) and obtains reproduction signal of recording data of the optical disc (6), and a light emission amount control means (22) that controls a light emission amount of the semiconductor laser (1) by the laser driving circuit (21) so as to keep a peak intensity of a focused light spot formed on an information recording layer of the optical disc 6 to be greater than or equal to a peak intensity at which a super-resolution effect is obtained.

Abstract: In accordance with an exemplary embodiment of the present invention, a method for measuring a quality parameter of an optical storage system comprising a non-diffraction-limited optical storage medium and a readout device, the method comprising the process of deriving an impulse response of the optical storage system, and the process of analyzing the impulse response to determine at least one of a width of the impulse response and a skewness of the impulse response as the quality parameter.

Abstract: Provided is an optical disc apparatus and an optical disc recording method, in which it is decided whether or not an optical disc recording medium is one of DVD-RW and DVD+RW when data is recorded in the medium. If it is decided that the medium is one of DVD-RW and DVD+RW, maximum length information is read out from a storage portion. The maximum length information contains a previously set maximum data length of data recorded to the medium by an optical pick-up portion in one recording operation. Data to be recorded is split into split data having a data length of the maximum data length or smaller. Further, an electric power value of a base electric power for controlling the semiconductor laser element to emit a laser beam with a bottom power is reset every recording operation of the split data.

Abstract: A disk drive is disclosed comprising a head actuated over a disk, wherein the head comprises a laser operable to heat the disk while writing data to the disk. A laser power of the laser is initialized, and a test pattern is written to the disk. The test pattern is read from the disk to generate a read signal, and a quality metric and a track width of the test pattern is measured based on the read signal. The laser power is adjusted and the process is repeated until at least one of the quality metric substantially matches a target value and the track width substantially matches a track width threshold.

Abstract: An optical disc device includes an optical pickup unit including a semiconductor laser that shines a laser light, a light-receiving unit that receives the return light of the laser light, a high-frequency generating circuit that generates high-frequency signals, a pickup driver that generates a drive signal that drives the semiconductor laser based on the high-frequency signal, a control unit that controls the high-frequency generating circuit such that, in states in which playback of the optical disc is halted while irradiation with the laser light is being performed, the signal level of the high-frequency signal to be superimposed is set at a first signal level other than zero so as to be smaller than in states in which the playback is performed.

Abstract: A thermally-assisted magnetic recording (HAMR) disk drive uses a thermal sensor to accurately monitor laser power during writing. The disk drive controller, or a separate processor, computes a prediction of the laser power from a history of laser power settings. This predicted value is compared with the measured value from the thermal sensor. If the difference is too large or too small, indicating that the laser power is too high or too low, an error signal is sent to the disk drive controller. The disk drive controller may adjust the laser power setting and initiate a re-write of the data. The predicted laser power is calculated from a convolution of a sequence of current and prior laser power settings with a sequence of coefficients. A calibration process generates the sequence of coefficients when the disk drive is idle or just after it is powered on.

Abstract: Methods, software, and apparatuses for reading from and/or writing to an optical storage medium. The methods generally include steps for reading a region of an optical storage medium to produce a readback signal, processing predetermined pattern data to produce one or more measurement instructions, measuring one or more characteristics of the readback signal in response to the measurement instructions to produce one or more measurement results, and further processing the readback signal in accordance with one or more of the measurement results. Thus, the ability to flexibly set test parameters and to quickly and accurately test the write characteristics of a recordable or re-writable optical storage medium is provided.

Abstract: In an optical information storage medium reproduction apparatus for reproducing an optical information storage medium including a plurality of information recording layers each including a recording mark having a length shorter than an optical system resolution limit, reproduction laser power for reading an information recording layer closest to a reproduction-laser-incident surface of the optical information storage medium is set to be lower than reproduction laser power for reading an information recording layer farthest from the reproduction-laser-incident surface but not lower than minimum reproduction laser power that satisfies a reproduction signal characteristic that the optical information storage medium reproduction apparatus requires.

Abstract: In an optical recording method, recording parameters (WU) to be used for recording are obtained using recommended recording parameter values (WR) read from an optical recording medium and previously obtained vector information (PC) and approximation coefficients (Ca, Cb) (S24). Writing to the optical recording medium is performed using the obtained recording parameters (S17). The vector information (PC) includes a vector component of the parameters obtained statistically with respect to parameter difference values (DF) between optimal recording parameter values (WO) and the recommended recording parameter values (WR) over a plurality of optical recording media so as to strengthen mutual correlation between the parameters.

Abstract: An information erasing device includes a recording section where recording is performed with regard to a disk-shaped recording medium, and a control section which controls the recording section so that the recording section overwrites a part of a erasing target sector so as not to overlap in a radius direction of the disk-shaped recording medium.

Abstract: Provided are a method of optical writing on a disc and a device adopting the method. The method of optical writing includes initially driving a laser diode (LD) at a preset reference value corresponding to a target output, detecting an actual output power by monitoring light output by the LD, and comparing the actual output power to the target output power. The method further includes compensating the reference value and writing data to the optical disc using the compensated reference value.

Abstract: A reproduction method for reproducing a rewritable and readable optical information storage medium in such a manner that an information recording layer is disclosed. The reproduction method comprising: reading setting information of reproduction laser power for each information recording layer of the rewritable and readable optical information storage medium, the setting information being stored in the rewritable and readable optical information storage medium; and setting, based on the setting information thus read, reproduction laser power for the information recording layer that is closest to a reproduction-laser-incident surface to be not less than 1.0 mW but less than 1.1 mW.

Abstract: To provide an optical disk device, an optical disk control method and an integrated circuit, which are capable of writing a recordable mark by changing the reflectance ratio of a reflective film formed on concave-convex pits without using an industrial special device or a high-power laser light source. A data reproduction controller (103) sets a first rotation speed in a disk rotation speed switching unit (108) and a first laser power in a laser power switching unit (107) when reproducing the concave-convex pits. When writing the recordable mark, a mark recording controller (104) sets in the disk rotation speed switching unit (108) a second rotation speed that is slower than the first rotation speed and the lowest rotation speed at which the concave-convex pits can be reproduced, and sets a second laser power greater than the first laser power in the laser power switching unit (107) in accordance with the emission timing.

Abstract: Provided is an optical write device and method. The optical recording method includes generating a first signal including a preset write pulse power Pm in response to information to be written, generating a second signal including an over drive pulse power Po that is synchronized with the preset write pulse power Pm and which is at a higher level than the preset write pulse power Pm, and writing the information to an optical disc using a driving signal that is obtained by synthesizing the first and second signals.

Abstract: An optical disc device comprising: a controller for reading data from an optical disc having a plurality of recording layers, wherein: the controller, in shifting a focus of the laser light from a first layer to a second layer, performs a first change that changes a setting on the high frequency signal to a predetermined value at which the high frequency signal is superimposed to suppress peak power of the drive signal if a light density of the second layer is higher than a light density of the first layer; the controller shifts the focus from the first layer to the second layer; and the controller, after the focus has been shifted, performs a second change that changes the setting on the high frequency signal to a predetermined value at which the high frequency signal is superimposed to increase the peak power of the drive signal.

Abstract: A reproducing device includes: a laser light irradiating section; a correction coefficient information retaining section; a correction coefficient obtaining section; a laser power setting section; and a driving signal outputting section.

Abstract: An optical disc device uses an optical disc (6) capable of super-resolution reproduction, and includes a semiconductor laser (1), a laser driving circuit (21) that supplies a driving current to the semiconductor laser, a light receiving element (8) that detects return light from the optical disc (6) and obtains reproduction signal of recording data of the optical disc (6), and a light emission amount control means (22) that controls a light emission amount of the semiconductor laser (1) by the laser driving circuit (21) so as to keep a peak intensity of a focused light spot formed on an information recording layer of the optical disc 6 to be greater than or equal to a peak intensity at which a super-resolution effect is obtained.

Abstract: A method for servoing when reading out a recorded holographic disk or recording in a preformatted disk includes detecting a primary signal of a reflected primary beam from a target data track of a target data layer of the disk, wherein the primary beam of radiation has a first wavelength; comparing a power measurement of the primary signal with a threshold value of power; detecting a tracking signal of a reflected tracking beam from a reference layer of the disk in an event that the power measurement of the primary signal is below the threshold value, wherein the tracking beam of radiation has a second wavelength; generating a servo error signal based upon the primary signal or the tracking signal; actuating an optical sub-system based upon either of the primary servo error signal or the tracking servo error signal such that the primary beam focuses on the target data layer.

Abstract: An optical disc drive includes a memory stored a write strategy, a converting unit which converts a recording data into a recording pulse based on the write strategy stored in the memory, an inspection unit which inspects a state of the recording data from a reproducing signal, a recording controller which executes a recording operation to record the recording data by applying a laser beam corresponding to the recording pulse to an optical disc, suspends the recording operation, judges whether correction of the write strategy according to an inspection result of the inspection unit is necessary, and restarts the recording operation after the write strategy saved in the memory is collected, and a correction unit which corrects the write strategy saved in the memory when the correction of the write strategy according to an inspection result of the inspection unit is necessary.

Abstract: An optical storage apparatus and a method for automatically adjusting a loop gain thereof are provided. The method includes the following steps. Firstly, a compact disk is written by an erase power. Next, a writing state of the erase power is detected to generate an error signal. Finally, a loop gain of a servo control loop is corrected according to the error signal. Therefore, the loop gain can be corrected by the present invention according to a reflectance of the compact disk.

Abstract: The invention relates to recording methods for recording information on a dual layer recordable disk, and to corresponding recording devices. In one such method and recording device the OPC-area is variably located on a layer of the disk. In a preferred embodiment the OPC-area is located relative close to the radius where the data stream switches from the first layer to the second layer. This reduced additional time required for jumping to a fixed OPC-area. Furthermore, in another such method and device the information to be recorded is equally divided over both layers of the dual layer disc. This avoids additional time required for finalization.

Abstract: An information recording/reproducing method includes: setting light beam power from a light source, to second power P2, which is weaker than first power P1, and detecting the number of the recording layers provided for an optical disc; controlling an objective lens to focus the light beam on one recording layer which is the closest to the objective lens, in a condition that the detected number of the recording layers ?3; setting the power of the light beam to third power P3, between P1 and P2; specifying the number of the recording layers provided for the optical disc on the basis of layer information, which is information associated with the one recording layer; and setting the power of the light beam to P1, reading the layer type information recorded in advance in the one recording layer, and specifying a disc type based on the read layer type information.

Abstract: A device and method for controlling a driving current with respect to an optical source of an optical disc drive are provided. The method includes changing a characteristic of a high frequency component based on a change in the peripheral temperature of on optical pickup device, modulating the driving current using the high frequency component, and applying the modulated driving current to the optical source.

Abstract: To ensure a favorable recording characteristic for a write-once recording medium for a bluish-purple laser, an optical information recording apparatus includes ways to write power to form recording marks, a space forming power to form spaces, a pulse width of a cooling pulse and ways to record information onto the optical information recording medium according to the setting of the write power, the setting of the space forming power and the setting of the pulse width of the cooling pulse. At this time, the pulse width of the cooling pulse and a ratio whose numerator is the write power and whose denominator is the space forming power have a preferable region of the recording characteristic, and information is recorded onto the optical recording medium by using values in this range.

Abstract: High power optical disc drives are disclosed. The drives are configured to deliver laser energy having a power of at least about 25 mW as measured at DVD 1× write speed upon first contact with the surface of an optical disc.

Abstract: An optical disc apparatus, for recording or reproducing information by irradiating a laser beam on an optical disc. More particularly, the present application relates to an optical pickup of the optical disc apparatus that produces a tracking error signal, in general, and the optical disc apparatus executes a tracking servo with using the tracking error signal.

Abstract: In accordance with an exemplary embodiment of the present invention, a method for measuring a quality parameter of an optical storage system comprising a non-diffraction-limited optical storage medium and a readout device, the method comprising the process of deriving an impulse response of the optical storage system, and the process of analyzing the impulse response to determine at least one of a width of the impulse response and a skewness of the impulse response as the quality parameter.

Abstract: The present invention can control output of pulses from a semiconductor laser. In the present invention, a short-pulse light source (1) applies a laser drive voltage (DJ) having a pulse-shaped drive voltage pulse (DJw) to a semiconductor laser (3), thereby causing the semiconductor laser (3) to emit specific output light (LAp), as laser light (LL), having a pulse-shaped specific peak (APK) and a specific slope (ASP), an emission intensity of the specific slope (ASP) being lower than an emission intensity of the specific peak (APK). The short-pulse light source (1) controls a voltage pulse half-width (Thalf), which is a pulse width of the drive voltage pulse (DJw), by setting a pulse width (Ws) of a set pulse (SLs), thereby adjusting a ratio between the specific peak (APK) and the specific slope (ASP).

Abstract: A method and an apparatus for reading data from or writing data to an optical recording medium is described, the data being stored as marks having different lengths. Marks having a length below the limit of diffraction at a first wavelength are read or written with the first wavelength, whereas marks having a length above the limit of diffraction at the first wavelength are read or written with a second wavelength larger than the first wavelength.

Abstract: Embodiments disclosed herein relate to an optical disc drive test. In one embodiment, an optical disc drive of a host electronic device performs a test on itself. The host electronic device requests information about the test from the optical disc drive. The optical disc drive reports information about the test in response to the request.

Abstract: To record information as an array of optically changed portions arranged along a track in an optical storage medium, a pulsed laser beam is emitted toward the optical storage medium while causing at least one of the optical storage medium and the pulsed laser beam to be moved relative to each other. A plurality of pulses of the pulsed laser beam are emitted during a time span in which one segment of the track having a length corresponding to a length of one optically changed portion is scanned with the pulsed laser beam. An intensity of light with which a segment of the track is to be illuminated to form each individual optically changed portion is adjusted by causing a shutter to selectively reduce the number of pulses of the pulsed laser beam with which the segment of the track is to be illuminated.

Abstract: In an optical information storage medium reproduction apparatus (10) for reproducing an optical information storage medium including a plurality of information recording layers each including a recording mark having a length shorter than an optical system resolution limit, reproduction laser power for reading an information recording layer closest to a reproduction-laser-incident surface of the optical information storage medium is set to be lower than reproduction laser power for reading an information recording layer farthest from the reproduction-laser-incident surface but not lower than minimum reproduction laser power that satisfies a reproduction signal characteristic that the optical information storage medium reproduction apparatus (10) requires.

Abstract: In an optical information storage medium reproduction apparatus (10) for reproducing an optical information storage medium including a plurality of information recording layers each including a recording mark having a length shorter than an optical system resolution limit, reproduction laser power for reading an information recording layer closest to a reproduction-laser-incident surface of the optical information storage medium is set to be lower than reproduction laser power for reading an information recording layer farthest from the reproduction-laser-incident surface but not lower than minimum reproduction laser power that satisfies a reproduction signal characteristic that the optical information storage medium reproduction apparatus (10) requires.

Abstract: In an optical information storage medium reproduction apparatus (10) for reproducing an optical information storage medium including a plurality of information recording layers each including a recording mark having a length shorter than an optical system resolution limit, reproduction laser power for reading an information recording layer closest to a reproduction-laser-incident surface of the optical information storage medium is set to be lower than reproduction laser power for reading an information recording layer farthest from the reproduction-laser-incident surface but not lower than minimum reproduction laser power that satisfies a reproduction signal characteristic that the optical information storage medium reproduction apparatus (10) requires.

Abstract: In an optical disc device, a way of canceling a lens shift due to an electric offset of an output of a tracking actuator driving circuit is desired. A tracking servo control circuit contains a first operation mode for setting an output current of the tracking actuator driving circuit to generally zero and a second operation mode for supplying a predetermined potential to the input. An average potential of a push-pull signal detected in the first operation mode is acquired. An object lens is moved by a predetermined amount in both radial directions by changing a potential supplied in the second mode to acquire correlative relationship between average potential of a push-pull signal relative to a lens movement amount and the supplied potential. An offset amount is acquired from the potential and the correlative relationship to cancel the offset.

Abstract: Power consumption is calculated in accordance with an operation state of disk devices without using a power meter in a storage system. The power consumption in accordance with the operation state is calculated as follows. That is, information on the power consumption for every type of hard disks is stored in advance when types of I/O process (random/sequential of read and write) operate at idle time up to a limit state in every type of hard disks. A control unit of the storage system aggregates time waiting a response from the hard disks in every type of I/O process. The power consumption of the disks is calculated on the basis of the information on the power consumption stored in advance and a sum of the waiting time of the response from the hard disks.

Abstract: A recording device includes a light irradiation portion which irradiates an optical recording medium with laser light emitted from a light source via a field lens, a light emission drive portion which drives and causes the light source to emit light, a front monitor which receives the laser light emitted from the light source, a light receiving portion which receives reflected light which is obtained from the optical recording medium in response to the laser light irradiation, a focus servo control portion which controls a focus servo of the field lens on the basis of a light receiving signal by the light receiving portion, a surface jump controller which controls the focus servo control portion so as to perform a focus jump operation to a surface of the optical recording medium, and a surface APC corrector which performs a process as an auto power control (APC) correction process.

Abstract: Systems, methods and compute program products for compensating for asymmetry variations are described. The asymmetry variations may be monitored both circumferentially and radially across an optical storage medium such that effects of the asymmetry variations may be compensated or minimized. In some implementations, effects of asymmetry variations may be compensated or minimized by first determining light reflected from a circumferential location of an optical storage medium. Then, at least one quality measure based on the detected light is determined. The correlation may be established based on the at least one quality measure and a corresponding circumferential location. A power level of a light source that emits the light is then adjusted based on the correlation.

Abstract: According to a method for setting the laser beam power applied to reproduce information recorded on an optical disc, information recorded in a region on the optical disc is reproduced using three or more test reproduction powers (S22B), the number of reproductions until the degradation of the quality of the reproduced signal reaches a prescribed value is determined as the degradation number of reproductions (S22F), the relation between the test reproduction power and the degradation number of reproductions is approximated by a curve, and a reproduction power restricting the degradation of the reproduced signal quality to a predetermined amount or less over a certain guaranteed number of reproductions is determined (S25F). In optical reproduction from an optical disc on which information is recorded, the optimum power of irradiation for reproduction can be set, and degradation of the information due to the reproducing light can be prevented.

Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.

Abstract: The invention relates to the field of the optical recording of information on a medium, such as an optical disc. To read an optical disc in super-resolution mode, a procedure for optimizing the power of the read laser beam is implemented. This optimization is based on the observation that a correlation exists between the power allowing the disc to be read without risk in super-resolution mode and the reflectivity of the sensitive layer containing the information. The reflectivity of the optical disc is measured for several power levels of the read laser, a critical power is determined on the basis of the reflectivity measurements made, and a read power sufficiently above the critical power, so as to be well outside a range of power levels entailing risks, is selected according to the critical power.

Abstract: Aspects of the disclosure can provide a method to optimize optical recording. The method can include recording a pre-defined pattern on an optical medium according to a first write strategy, measuring edge timings corresponding to the pre-defined pattern recorded on the optical medium, determining a second write strategy including at least timing modifications to the first write strategy. The timing modifications can be determined based on means and variances of the measured edge timings, edge timing means and variances targets for desired edge timings, and edge timing sensitivities to the timing modifications.

Abstract: The present invention is related to a method and a reading device (1) for retrieving information from an optical record carrier (10) in which the read power level of a radiation beam (3) for scanning the optical record carrier is set in dependence on the read-out speed. The invention is also related to a record carrier for use with such a method and a reading device.

Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.