Light Intensity Adjustment Or Maintenance Patents (Class 369/116)
  • Patent number: 7564755
    Abstract: A pickup of an optical reproducing/recording apparatus having a laser diode generating an optical signal with a current power value, and a laser diode power control device automatically controlling an output of the laser diode. The laser diode power control device has a sampler sampling the current power value of the optical signal from the laser diode, an operation unit outputting a target output value based on a comparison of the sampled current power value and a basic power value depending on a type of medium that is to receive the output of the laser diode, and a controller controlling the output of the laser diode based on the target output value.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: July 21, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jin-gyo Seo, Kyoung-bok Jin
  • Patent number: 7564757
    Abstract: The optical disk recording apparatus includes: a strategy circuit for converting recording data into a pulse train signal for defining an irradiation timing of laser light by using one of first and second conversion rules for forming different marks; a control unit for changing the conversion rule used for the strategy circuit after a timing of forming a contour of an image has passed at the time of forming the image on an optical disk, and when a timing of addition of a synchronization pattern to EFM data has arrived; and a current selecting unit for selecting a current in accordance with the pulse train signal based on the strategy circuit and for supplying it to a semiconductor laser.
    Type: Grant
    Filed: April 23, 2004
    Date of Patent: July 21, 2009
    Assignee: Yamaha Corporation
    Inventors: Yukihisa Nakajyo, Morito Morishima
  • Patent number: 7561506
    Abstract: An information-recording method includes the steps of moving a light beam at a selected linear velocity relative to the information-recording medium; controlling the light beam to generate a multi-pulse having at least three power levels of a first power level Ph, a second power level P1 which is lower than the first power level, and a third power level Pm which is intermediate therebetween, the multi-pulse being repeatedly modulated between the first power level Ph and the third power level Pm; adjusting the third power level Pm in response to the selected linear velocity; and recording the information by irradiating the information-recording medium with the controlled light beam. Recording compatibility can be secured for information-recording apparatuses different in recording linear velocity and laser source characteristic.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: July 14, 2009
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Naoki Kitagaki, Makoto Miyamoto
  • Patent number: 7561508
    Abstract: The invention relates to recording on a medium, and in particular, to laser control during recording data on an optical medium. A laser control method for dynamically adjusting laser power during recording data onto an optical disc comprises: recording normal data onto the optical disc according to an initial laser power; stopping recording when a trigger is generated; reading back the recorded normal data and generating a first recording quality index; recording a test pattern at a test pattern starting point according to a selected laser power; reading back the test pattern and generating a second recording quality index; and determining an adaptive laser power to continually record the normal data according to the first recording quality index and the second recording quality index.
    Type: Grant
    Filed: February 1, 2006
    Date of Patent: July 14, 2009
    Assignee: Mediatek Inc.
    Inventors: Chih-Ching Yu, Hung-Hsiang Chang, Ping-Tsai Tsai
  • Publication number: 20090175152
    Abstract: Provided is an optical disk apparatus that suppresses shortening of the life time of a light source, degradation of the signal quality involved in an increase in quantum noise, and lowering of the slope efficiency, which are caused by a temperature increase of the light source by a lowering in the heat radiation performance of the light source due to size reduction or thickness reduction of the apparatus. As a specific structure, the optical disk apparatus includes an optical pickup including: a light source; a light source drive circuit; an optical base housing an optical system for guiding light emitted from the light source to a disk-shaped recording medium; a first heat radiation member connected to the light source; and a second heat radiation member connected to the light source drive circuit.
    Type: Application
    Filed: January 6, 2009
    Publication date: July 9, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Shinnosuke Torii
  • Patent number: 7558172
    Abstract: An optical disk device records data on a recordable or rewritable optical disk. The optical disk device comprises zone storing means for preliminarily storing locations of a plurality of zones set by dividing a recordable or rewritable area of the optical disk from an inner periphery thereof to an outer periphery thereof, position detecting means for detecting a position on the optical disk so as to record data at the position, judging means for judging which of the zones the position corresponds to by referring to the zone storing means, and controlling means for controlling the device to perform a data-recording by a CLV method to each of the zones specified by the judging means by setting a recording velocity and a recording power for each of the zones so as to enable the data-recording to provide an equal recording density to all of the zones.
    Type: Grant
    Filed: May 15, 2007
    Date of Patent: July 7, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Kei Hagiwara, Haruyuki Suzuki
  • Patent number: 7558182
    Abstract: To provide an optical head and an optical disc device, in which a cover member for radiating and protecting the optical head and a laser light source are of a simple construction, manufacturing efficiency can be increased, and accuracy variation due to assembly of the laser light source such as an optical axis or the like of a laser beam can be suppressed. Therefore, a boss formed on a light source installation portion of a base is engaged with a boss hole formed on a laser light source supporting portion of the cover member, thereby positioning the cover member on the base. In doing so, an internal thread hole formed on the bottom surface of the base is overlapped with a thread hole formed on a cover portion of the cover member. In this state, a bolt is passed through the thread hole to screw in the internal thread hole.
    Type: Grant
    Filed: August 29, 2006
    Date of Patent: July 7, 2009
    Assignee: Funai Electric Co., Ltd.
    Inventors: Yutaro Hamatani, Fumiaki Mori
  • Patent number: 7554895
    Abstract: An apparatus and method for controlling an operation of recording data employed in an optical storage system is disclosed. The apparatus has a sampling-and-holding circuit, an operational amplifier, a plurality of gain amplifiers, and a plurality of switches. The apparatus operates under a short-term open mode, a long-term open mode, and a closed-loop mode sequentially in response to control signals and close/open statuses of the switches. A write-control signal is initialized by using a virtual ground effect within the short-term mode. In the long-term mode, the write-control signal is charged to a voltage level suitable for recording data onto a compact disk, while the charged write-control signal is employed to record data on the compact disk within the closed-loop mode.
    Type: Grant
    Filed: January 14, 2004
    Date of Patent: June 30, 2009
    Inventors: Ting-Wen Su, Sung-Hung Li, Yi-Lin Lai
  • Patent number: 7554890
    Abstract: A method for recording data on an optical disc, includes detecting optimum writing power from a test area on the optical disc; determining whether or not a current writing power is within a predetermined allowable range set with reference to the detected optimum writing power; and performing a writing operation with the writing power controlled to maintain a reflection signal level corresponding to the detected optimum writing power when the current writing power is within the predetermined allowable range, and performing the writing operation with the writing power controlled based on power update information when the current writing power is not within the predetermined allowable range.
    Type: Grant
    Filed: March 3, 2004
    Date of Patent: June 30, 2009
    Assignee: Hitachi-LG Data Storage Korea, Inc.
    Inventor: Cheul Kyung Han
  • Publication number: 20090154326
    Abstract: Disclosed herewith is a data recording and reading equipment capable of reducing laser noise easily. At first, a laser beam source that can reduce the laser noise when reading data from a subject optical disk is obtained. A modulator capable of varying laser attenuation with a voltage is disposed so as to precede the laser, thereby the laser noise when reading data from the optical disk can be reduced without lowering the laser power when in writing.
    Type: Application
    Filed: February 17, 2009
    Publication date: June 18, 2009
    Inventors: Koichi Watanabe, Takahiro Kurokawa, Masahiro Aoki, Takeshi Shimano
  • Patent number: 7548495
    Abstract: A write retry processing unit repeats a write retry operation of a write and a verify, while performing a setting change of a focus offset for recording a data on an optical storage medium in case a verify error occurs in executing the write and a verify try fails. A learning processing unit retains a sum total of the number of adding times of the successful focus offset and the number of subtracting times of the successful retry offset as a learning result at the successful time of the write retry, and a write condition changing unit changes the focus offset setting value of the default so as to be drawn near to the latest focus offset which succeeds in the retry when the absolute value of the learning result retained in the learning processing unit is equal to or more than a threshold value.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: June 16, 2009
    Assignee: Fujitsu Limited
    Inventor: Shinya Kobayashi
  • Patent number: 7545719
    Abstract: An optical disk apparatus is capable of recording a signal on an optical disk by directing an optical beam thereon at a plurality of recording speeds. A condition measuring position storing part stores one or more condition measuring positions at which a condition of the signal is measured for each of the recording speeds. A signal condition measuring part measures the condition of the signal by suspending recording operations at the condition measuring positions stored in the condition measuring position storing part. In the condition measuring position storing part, a condition measuring position for a recording speed whose level is one level lower than the level of a predetermined recording speed are set to positions shifted for a predetermined time interval from respective condition measuring positions for the predetermined recording speed.
    Type: Grant
    Filed: November 18, 2003
    Date of Patent: June 9, 2009
    Assignee: Mitsumi Electric Co., Ltd.
    Inventors: Kenichi Furukawa, Masao Fukaya
  • Patent number: 7542400
    Abstract: A laser diode (LD) driver and method of compensating for a bias driving potential of an LD driver according to a change in a power level of a laser signal from an LD in a recording mode include storing the bias driving potential, detecting a change in a bias power level in the laser signal, and compensating the bias driving potential according to the detected change in the bias power level.
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: June 2, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Seo Jin Gyo
  • Patent number: 7539109
    Abstract: A recording method for an optical disc drive and an optical disc drive wherein a surrounding temperature is measured by a temperature sensor serving as temperature measuring device, a set surrounding temperature is correlated with a set recording rate by using a data table stored in an internal memory of a controller serving as correlating device, and a recording rate is changed by a digital signal processing portion serving as recording control device based on the surrounding temperature measuring result and the correlating result. The recording rate is changed by changing a ratio of a recording operation time and a recording-stop operation time with alternately repeating a recording operation and a recording-stop operation at as low a laser beam output as playback.
    Type: Grant
    Filed: November 8, 2004
    Date of Patent: May 26, 2009
    Assignee: Panasonic Corporation
    Inventors: Katsuo Hori, Kenji Takauchi, Toshiya Akagi, Yasushi Ouchi
  • Patent number: 7539110
    Abstract: An optical information recording medium for recording information by a plurality of record mark lengths, wherein the shortest mark length is at most 0.5 ?m, and a crystal state is an unrecorded or erased state and an amorphous state is a recorded state, wherein the erasing is carried out by recrystallization which substantially proceeds by crystal growth from an interface between the amorphous portion or a melt portion and a peripheral crystal portion; and an optical recording method suitable therefore. The medium of the present invention has characteristics that overwriting can be made at a high speed, the jitter of mark edge is small, mark length modulation recording can be made at a high density, and the formed mark is excellent in the stability with the lapse of time.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: May 26, 2009
    Assignee: Mitsubishi Kagaku Media Co., Ltd.
    Inventors: Hironobu Mizuno, Takashi Ohno, Michikazu Horie
  • Patent number: 7535941
    Abstract: A laser-drive-current control circuit outputs a drive current indicating signal for indicating a laser drive current for driving a laser light emitting element that emits a laser beam to an optical disk and controls the output of the laser drive current based on a light emission monitor signal.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: May 19, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Inoue, Akira Nakao, Yasuhiro Hayashi
  • Patent number: 7535806
    Abstract: Improvements to an optical recording apparatus comprising a laser light source are provided. The improvements include installing a photodiode in an optical path of at least a portion of the laser light beam from the laser light source, and connecting said photodiode to a detection circuit. The photodiode detects the laser light beam and generates a detection signal based on the detected beam. The detection circuit monitors the detection signal and generates an alarm signal if the detection signal indicates a dropout in the laser beam. The alarm signal can trigger an alarm indicator and/or cause a recording process to be halted.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: May 19, 2009
    Assignee: Cinram International Inc.
    Inventor: Samuel Fumanti
  • Patent number: 7532554
    Abstract: When a space region shorter than the radius of a beam spot is formed, pre-heating with an assist pulse is not performed, and an off pulse pattern is fixed at a base power level. When a space region longer than the radius of the beam spot and shorter than the diameter of the beam spot is formed, an assist pulse is applied to the end of the space region to be formed. The length of the assist pulse is made greater, the longer the space region to be formed. Further, when a space region longer than the diameter of the beam spot is formed, an assist pulse is applied to the end of the space region to be formed, and the length of the assist pulse is kept constant regardless of the length of the space region to be formed.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: May 12, 2009
    Assignee: TDK Corporation
    Inventors: Tatsuhiro Kobayashi, Koji Mishima
  • Patent number: 7532555
    Abstract: In an optical recording method used when information is recorded in a phase-change recording layer of a large-capacity rewritable optical recording medium such as a DVD-RW, one block pulse is used as a recording pulse for forming one recording mark when a recording velocity is higher than a recording linear velocity at which the rewritable optical recording medium can be rewritten, whereas a pulse train comprised of a plurality of short pulses is used as the recording pulse for forming one recording pulse when the recording velocity is within recording linear velocities at which the rewritable optical recording medium can be rewritten, whereby high-velocity recording is realized.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: May 12, 2009
    Assignee: Mitsubishi Kagaku Media Co., Ltd.
    Inventors: Masaaki Mizuno, Hiroyuki Hoshino, Takashi Ohno, Michikazu Horie
  • Patent number: 7532550
    Abstract: When setting a recording power for use in recording optical information on a DVD-R, by using any one of sectors provided on the DVD-R as a PCA, whether a predetermined special detected signal is detected or not in the sectors is checked (Step S2), a non-used sector where no special detected signal is detected, of the sectors, is retrieved, based on the check result (Step S3), a mark signal for obtaining the special detected signal is recorded in the retrieved non-used sector (Step S5), a setting signal for setting a recording power is recorded in the non-used sector excluding the area where at least the mark signal is recorded (Step S6), and the recorded setting signal is optically detected to set the recording power (Step S13).
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: May 12, 2009
    Assignee: Pioneer Corporation
    Inventor: Masayoshi Yoshida
  • Publication number: 20090116365
    Abstract: An optical recording method to record information with a mark length recording method, where an amorphous mark and a crystal space are recorded only in the groove of a substrate having a guide groove, with the temporal length of the mark and the space of nT (T denotes a reference clock period; n denotes a natural number). The space is formed at least by an erase pulse of power Pe; all the marks of 4T or longer are formed by a multi pulse alternatively irradiating a heating pulse of power Pw and a cooling pulse of power Pb while Pw>Pb; and the Pe and the Pw satisfy the following relations: 0.15?Pe/Pw?0.4, and 0.4??w/(?w+?b)?0.8, where ?w denotes the sum of the length of the heating pulses, and ?b denotes the sum of the length of the cooling pulses.
    Type: Application
    Filed: March 31, 2006
    Publication date: May 7, 2009
    Applicant: Ricoh Company, Ltd.
    Inventors: Kazunori Ito, Eiko Hibino, Mikiko Takada, Hiroshi Deguchi, Hiroko Ohkura, Hiroshi Miura
  • Patent number: 7529172
    Abstract: An optical disk recording and playback device comprises a first laser driving circuit that supplies a driving signal to a first laser diode, a second laser driving circuit that supplies a driving signal to a second laser diode, a signal recording pulse generating circuit that generates a signal recording pulse signal in accordance with a signal to be recorded on a signal recording layer, and outputs the signal recording pulse signal to the first laser driving circuit, and an image recording pulse generating circuit that generates an image recording pulse signal in accordance with a signal to form an image on an image recording layer, and outputs the image recording pulse signal to the second laser driving circuit. When recording of a signal to the signal recording layer and recording of an image to the image recording layer are simultaneously performed, the first laser diode and the second laser diode are controlled to prevent light emission from simultaneously occurring at recording levels.
    Type: Grant
    Filed: February 23, 2006
    Date of Patent: May 5, 2009
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Akira Tsukihashi, Tsuyoshi Yamamoto
  • Patent number: 7525890
    Abstract: A method of and apparatus for recording data on an optical recording medium form a mark or a space by using a recording waveform having an erase pattern containing a multi-pulse. The method and the apparatus prevent distortion of the mark or the space and improve a mark shape such that a recording/reproducing characteristic of the optical recording medium is improved.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: April 28, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yong-jin Ahn, In-sik Park, Kyung-geun Lee, Chang-jin Yang, Tatsuhiro Otsuka, Du-seop Yoon, Seong-sue Kim
  • Patent number: 7525888
    Abstract: An optical information recording apparatus can maintain a stable recording quality when recording information on an optical information recording medium having a recording layer of a multilayer structure. An optical information recording medium of a rotating type has a plurality of recording layers each having an information recording area in which information is recorded using a laser beam. An inner power calibration area is provided in each of the recording layers at a location closer to a center of rotation of the optical information recording medium than the information recording area, and is used to perform a test write in an optimum power control process to acquire an optimum recording power of the laser beam. The outer power calibration area is provided at a location farther from the center of rotation than the information recording area, and is used to perform a test write in an optimum power control process to acquire an optimum recording power of the laser beam.
    Type: Grant
    Filed: April 23, 2007
    Date of Patent: April 28, 2009
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaki Ninomiya
  • Patent number: 7522509
    Abstract: In an optical disc device, the recording laser light power from a semiconductor laser is adjusted to a desired power. A front monitor PD is provided near the semiconductor laser LD of an optical pickup 16, and the recording layer light power is detected. A system controller 32 stores in memory an approximating equation for a correction coefficient for the recording power based on the detection signal characteristic when the recording laser light is a multi-pulse signal, uses the approximating equation to compute the correction coefficient for the desired recording power, corrects the detected signal level from the front monitor PD, and executes feedback control of the laser power emitted from the LD.
    Type: Grant
    Filed: May 20, 2004
    Date of Patent: April 21, 2009
    Assignee: TEAC Corporation
    Inventors: Takashi Miyamoto, Tomohisa Inaba, Kiyoshi Shidara
  • Patent number: 7518975
    Abstract: An operating current modifying device is provided for a power generating element. The power generating element generates an output power when the operating current is larger than a threshold current in the power generating element. A functional relationship exists between the threshold current and the temperature of the electrical device. The operating current modifying device may include a threshold current modifying module, a power modifying module, a current compensating module, and a power control module.
    Type: Grant
    Filed: January 26, 2006
    Date of Patent: April 14, 2009
    Inventors: Ronnie Lai, Ronald Chen
  • Patent number: 7512057
    Abstract: Disclosed is a laser pulse controlling circuit that, when the laser device is driven with laser pulses having the first and the second illumination levels, causes the first and the second illumination level setting units to set the first and the second illumination levels corresponding to a predetermined ratio of the first illumination level to the second illumination level, wherein the laser pulse controlling circuit, based on regularity that the relation between: a manipulated variable for causing the second illumination level setting unit to execute adjustment of the second illumination level; and the inverse of the ratio, with reference to the first illumination level, is a straight line that necessarily passes one point for a predetermined first illumination level, and that the slope of the straight line is proportional to an arbitrary first illumination level, calculates the manipulated variable that is correlated with the first illumination level corresponding to the optical disk, and with the inverse
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: March 31, 2009
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Katsuya Tanoue, Kenichi Ikegami, Naoya Yamakawa
  • Patent number: 7512049
    Abstract: An optical pickup apparatus comprises a semiconductor laser output controller for emitting laser beam, a photodetector for detecting the emitted laser beam, a sampling processor for performing a sampling process, a pulse current generator for generating erase current pulses, write current pulses, and read current pulses, and a controller for controlling the above components. The apparatus performs the sampling process and generates the current pulses according to a predetermined APC timing and controls the semiconductor laser output controller based on the sampling process and current pulses.
    Type: Grant
    Filed: January 9, 2004
    Date of Patent: March 31, 2009
    Assignee: Pioneer Corporation
    Inventors: Kiyoshi Tateishi, Junichi Furukawa
  • Patent number: 7505384
    Abstract: Laser power adjustment is performed using a power calibration area (PCA) until the PCA is used up. After the PCA is used up, an additional PCA is reserved at the next recording start position and laser power adjustment is performed using the additional PCA. When an additional PCA is reserved, the additional PCA exists between an information file recorded this time and the last one of information files recorded previously in terms of a physical format. However, information test-written into the additional PCA is not regarded as an information file and PMA information is generated only from the information file recorded this time by excluding the test-written information. As a result, a situation is obtained in which the additional PCA does not logically exist on the disk and there will never occur an inconvenient situation where the additional PCA is erroneously reproduced at the time of reproduction.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: March 17, 2009
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Kenji Nakao, Noboru Mamiya, Ken Hirose
  • Patent number: 7505387
    Abstract: A method and an apparatus which controls write power of an optical driver by optimizing the number of channels used to drive a laser diode in a write mode while stabilizing the level of a write power voltage at an early stage of the write mode. The method of controlling the write power includes checking whether the write power provided to the laser diode included in the optical driver is stable, controlling the write power by increasing the number of channels used to control the write power so as to provide sufficient write power to drive the laser diode in response to the write power provided to the laser diode being unstable, and controlling the write power by using less channels than the channels used in response to the write power being unstable in response to the write power provided to the laser diode being stable. Accordingly, it is possible to reduce the size of a firmware by preventing channels unnecessary to perform a write mode from being used.
    Type: Grant
    Filed: June 13, 2002
    Date of Patent: March 17, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Joo-yeup Kim, Jin-gyo Seo
  • Patent number: 7505388
    Abstract: A laser controller includes a timing signal generator configured to generate a timing signal for controlling the irradiation timing of the laser in accordance with input data. A mask signal generator is configured to generate a mask timing signal for masking the timing signal in accordance with the input data.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: March 17, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kunihiko Kodama, Takashi Inoue
  • Patent number: 7502303
    Abstract: An optical pick-up device includes a laser diode, an objective lens for focusing a light beam emitted from the laser diode on an optical disc, an optical detector for receiving a reflected beam from the optical disc, a beam splitter for causing the light beam emitted from the laser diode and a reflected beam to pass therethrough or reflect, a front monitor for receiving the light beam emitted from the laser diode, and a front monitor light-guiding plate for guiding a part of the light beam emitted from the laser diode to the front monitor. The front monitor light-guiding plate is arranged between the laser diode and the objective lens and has a region having a predetermined shape for causing the part of the light incident thereon to change a traveling direction thereof by refraction and then reach the front monitor.
    Type: Grant
    Filed: August 1, 2005
    Date of Patent: March 10, 2009
    Inventors: Tomoto Kawamura, Sayako Itoh, Daisuke Tomita
  • Patent number: 7502302
    Abstract: Disclosed herewith is a data recording and reading equipment capable of reducing laser noise easily. At first, a laser beam source that can reduce the laser noise when reading data from a subject optical disk is obtained. A modulator capable of varying laser attenuation with a voltage is disposed so as to precede the laser, thereby the laser noise when reading data from the optical disk can be reduced without lowering the laser power when in writing.
    Type: Grant
    Filed: July 29, 2005
    Date of Patent: March 10, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Koichi Watanabe, Takahiro Kurokawa, Masahiro Aoki, Takeshi Shimano
  • Publication number: 20090052306
    Abstract: The present invention provides a laser generator that allows recording quality to be improved, a method of controlling the laser generator, and an optical disk device. In a laser emitting device including a semiconductor laser diode emitting laser and a semiconductor laser diode driving section supplying a driving pulse to the semiconductor laser diode to drive the semiconductor laser so as to blink on the basis of the driving pulse, an impedance between the semiconductor laser diode and the semiconductor laser diode driving section is controlled to an appropriate condition.
    Type: Application
    Filed: March 28, 2008
    Publication date: February 26, 2009
    Inventors: Naohito Ikeda, Koichi Watanabe
  • Patent number: 7496011
    Abstract: A drive apparatus including: a superposition device which superposes a superposition signal on a drive signal for driving a light beam emission device that emits a light beam and which outputs the drive signal on which the superposition signal is superposed to the light beam emission device, a reference clock signal generation device which generates a reference clock signal, a frequency change device which changes a frequency of the superposition signal based on a quality index for indicating a quality of a reproduction signal that is obtained from a reflection light that is the light beam reflected on a record medium, a phase locked loop device which controls the changed frequency so as to be constant by a feedback method in use of the generated reference clock signal.
    Type: Grant
    Filed: March 14, 2005
    Date of Patent: February 24, 2009
    Assignee: Pioneer Corporation
    Inventors: Junichi Furukawa, Kiyoshi Tateishi
  • Publication number: 20090046565
    Abstract: To provide a method for determining an optimum laser beam power for a single-side, dual-layer optical recording medium having first and second information layers, the method including: determining an optimum laser beam power based on a predetermined characteristic value at the time when the number of overwrite cycles on the recording medium is a predetermined value, wherein the method is conducted by an optical recording/reproduction apparatus utilizing optical change, and wherein the first information layer is closer to the laser irradiation side than is the second information layer.
    Type: Application
    Filed: February 15, 2007
    Publication date: February 19, 2009
    Inventors: Hajime Yuzurihara, Hiroyuki Iwasa, Hiroshi Deguchi
  • Patent number: 7492687
    Abstract: A plurality of types of recording pulse control rules for which the recording pulse waveform is determined according to the information signals to be recorded are stored in advance in an optical disk. When recording to the optical disk, information is recorded using a recording pulse where, due to the focused laser beam, the temperature in the recording layer cools more rapidly at a second information recording layer closer to the side where light is incident than at a first information recording layer farther away from the side where light is incident.
    Type: Grant
    Filed: September 20, 2007
    Date of Patent: February 17, 2009
    Assignee: Panasonic Corporation
    Inventors: Naoyasu Miyagawa, Kenichi Nishiuchi
  • Patent number: 7480221
    Abstract: In a method and apparatus for generating optimum write power, a control unit controls a write voltage generating unit to generate sequentially write voltages of different levels to drive an optical read/write head to generate different write powers so as to write data on a plurality of write intervals of an optical recording medium in sequence. Simultaneously, a detecting and computing circuit detects a peak value, a first level and a second level of a write reflected signal generated by each write interval for computation so as to obtain a first control parameter of each write interval, and detects a peak value, a bottom value and a direct current level of a read reflected signal generated during reading of each write interval for computation so as to obtain a second control parameter of each write interval, thereby generating an optimum write power based on optimal first and second control parameters.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: January 20, 2009
    Assignee: Mediatek Inc.
    Inventors: Yuan-Chin Liu, Ming-Yang Chao
  • Patent number: 7480226
    Abstract: An optical disc recording/reproducing apparatus and optimum bias power decision method thereof, having an optical pickup, a driving unit which drives a laser diode provided in the optical pickup to emit light corresponding to a certain bias power, a bias power variation unit which varies the bias power and outputs the varied bias power to the driving unit, and a bit error rate measurement unit which reproduces the recorded data, compares the reproduced data and the recorded data, and measures at least one bit error rate. A controller is further provided which calculates a relationship equation between the measured bit error rate and the varied and output bias power upon recording the data, and decides an optimum bias power based on at least one maximum value and at least one minimum value in a curve obtained from the relationship equation.
    Type: Grant
    Filed: February 3, 2005
    Date of Patent: January 20, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sung-kyoo Kim, Min-seok Kim
  • Patent number: 7480230
    Abstract: A light source drive which modulates a light source so as to cause the same to emit a light, includes: a superposition current generation part which generates a superposition current approximately corresponding to a charging/discharging current needed for a capacitance occurring in parallel to the light source for a predetermined time period near at least one of a rising-up part and a decaying-down part of a waveform of a drive current for the light source; and an addition/subtraction part which adds to or subtracts from the drive current the superposition current generated by the superposition current generation part.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: January 20, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Naruhiro Masui, Hidetoshi Ema
  • Patent number: 7477590
    Abstract: The present invention relates to an optical recording medium having at least two information carrier layers, on which information can be written by means of a focused light beam. In this case, a separating layer is arranged between the information carrier layers and a respective transparent covering layer is arranged between the information carrier layer and the surface of the recording medium, the thickness of which covering layer substantially exceeds that of the information carrier layer. One object of the present invention is to propose an optical recording medium in the case of which it is possible to write to both information carrier layers using a low optical power. Further objects of the invention are to specify an apparatus and also a suitable method for writing to a recording medium of this type. A recording medium according to the invention has information carrier layers which are both semi-transparent.
    Type: Grant
    Filed: July 24, 2006
    Date of Patent: January 13, 2009
    Assignee: Thomson Licensing
    Inventors: Hartmut Richter, Dietmar Uhde
  • Patent number: 7477580
    Abstract: Provided are a method and apparatus for performing a writing test using charge pumps in an optical disk reproducing/recording apparatus. In the apparatus for performing the writing test, an optimum power control (OPC) determining unit determines a phase of a radio frequency signal using a reference voltage, and generates a corresponding OPC voltage; an analog-to-digital converter (ADC) unit converts the OPC voltage into a digital signal; and a micom controls a power control unit according to the digital signal, to appropriately control laser power.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: January 13, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: So-won Lee
  • Patent number: 7477587
    Abstract: An information-recording method includes the steps of moving a light beam at a selected linear velocity relative to the information-recording medium; controlling the light beam to generate a multi-pulse having at least three power levels of a first power level Ph, a second power level Pl which is lower than the first power level, and a third power level Pm which is intermediate therebetween, the multi-pulse being repeatedly modulated between the first power level Ph and the third power level Pm; adjusting the third power level Pm in response to the selected linear velocity; and recording the information by irradiating the information-recording medium with the controlled light beam. Recording compatibility can be secured for information-recording apparatuses different in recording linear velocity and laser source characteristic.
    Type: Grant
    Filed: December 15, 2003
    Date of Patent: January 13, 2009
    Assignee: Hitachi Maxwell, Ltd.
    Inventors: Naoki Kitagaki, Makoto Miyamoto
  • Patent number: 7477589
    Abstract: The present invention with an optical disk drive controller and an optical pickup head connected together by a flexible cable is described. The device includes a delay adjusting module located within the first module for delaying a first signal by an amount specified by a calibration signal. The first module transmits the delayed first signal and a second signal through a first signal channel and a second signal channel, respectively, to the second module of the optical pickup head, a monitoring module located within the optical pickup head for receiving and reshaping the delayed first signal and the second signal so as to generate a monitor signal. A calibration signal-generating module is located within the optical disk drive controller for receiving the monitor signal so as to generate the calibration signal.
    Type: Grant
    Filed: June 7, 2005
    Date of Patent: January 13, 2009
    Assignee: Mediatek Incorporation
    Inventors: Chia-Hua Chou, Chih-Cheng Chen
  • Publication number: 20090010143
    Abstract: The present invention provides an over drive power control system and a method which are capable of generating an optimized output power of the optical disk drive under a variation of operational environment. According to this invention, a photo detecting unit detects current laser power and generates a power feedback signal. A low frequency power control unit generates a modified power control signal by using the power feedback signal and an original power control signal. A high frequency power control unit generates a modified high frequency control signal for controlling the laser power according to a predetermined relationship among original and modified low power control signals and an original high frequency control signal. A digital-to-analog converter receives the modified high frequency control signal then outputs a adjusted write power signal for adapting the laser power to environmental variation and thus maintaining laser power in a constant state.
    Type: Application
    Filed: July 6, 2007
    Publication date: January 8, 2009
    Applicant: MEDIATEK Inc.
    Inventors: Choa-ming Huang, Yao-Iung Chuang
  • Patent number: 7474598
    Abstract: An optical reproducing device is provided with predetermined length mark signal measurement means which measures amplitude values of a 2T mark and an 8T mark, which are a short reproducing power control mark and a long reproducing power control marks, respectively, from information data recorded in an magneto-optical disk. Reproducing power of a light beam is controlled by a laser power control circuit, based on the amplitude values of the 2T mark and the 8T mark. The predetermined length mark signal measurement means detects a specific pattern including the 2T mark from a bit arrangement pattern of the information data, and measures the amplitude value of the 2T mark correponding only to the 2T mark included in the specific pattern. This structure can provide an optical reproducing device which can maintain the reproducing power at an optimum value and reduce the probability of reading errors, without reducing the utilization ratio of an optical recording medium.
    Type: Grant
    Filed: February 25, 2002
    Date of Patent: January 6, 2009
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tetsuya Okumura, Shigemi Maeda
  • Patent number: 7474603
    Abstract: A multilevel information recording apparatus is disclosed, which includes a control unit that inputs signals to a strategy generating unit and a laser drive unit based on the multilevel information being recorded, a signal indicating the playback and recording state, and a clock signal indicating the cell frequency that is in synch with the multilevel information. The strategy generating unit generates a pulse signal in accordance with the timing of the laser beam emission of a write pulse, an off pulse, a bias pulse, and a space pulse based on the signal from the control unit and the clock signal. The laser drive unit determines the driving current of a laser light source based on a delayed playback signal/delayed recording signal that is obtained by delaying the playback signal/recording signal for a processing time of the strategy generating unit, a pulse signal from the strategy generating unit indicating the emission timing of the pulses, and an intensity signal predetermined for each pulse.
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: January 6, 2009
    Assignee: Ricoh Company, Ltd.
    Inventor: Hiroshi Maegawa
  • Patent number: 7463563
    Abstract: The present invention provides a deficiency detecting apparatus that can accurately detect dusts and deficiencies on an optical disk even when an emitting power of a laser light source changes. The deficiency detecting apparatus is provided with a deficiency detecting section for detecting deficiencies or the like on an optical disk by reflected light, and a power adjusting section for adjusting an emitting power of a laser light source to be an optimum value. The deficiency detecting section can accurately detect the deficiencies on the optical disk even when the laser power changes by comparing a threshold value, which is determined in accordance with the adjustment result of the power adjusting section, with a value in accordance with the reflected light.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: December 9, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Eiji Ueda, Takashi Kishimoto, Shin-ichi Yamada
  • Publication number: 20080298216
    Abstract: The present invention discloses a method used in an optical disk drive for destroying data of an optical disk. The optical disk is rotated clockwise and the optical head moves one track per revolution. Then, the optical head is controlled so that the spot size of the emitted laser beam projected on the optical disk is about one track pitch wide and the laser beam has a destroy power. Thereafter, the laser beam with the destroy power is adopted to write the optical disk from the inner diameter to the outer diameter.
    Type: Application
    Filed: May 14, 2008
    Publication date: December 4, 2008
    Applicant: LITE-ON IT CORPORATION
    Inventor: Cheng-Yao Liao
  • Patent number: 7460461
    Abstract: An optical storage system includes an optical pickup unit movable across an optical medium. The optical pickup unit has a light detector, a laser diode, and a laser driver signal processor circuit. The laser driver signal processor circuit includes a detected signal processing block for outputting read signals corresponding to light received at the light detector, and a read signal processing block for processing the read signals and generating control signals or synthesis signals according to the read signals. A control unit is coupled to the optical pickup unit for controlling the optical pickup unit and decoding data recovered from the optical medium. The optical storage system further includes encryption and decryption modules or error detection modules for securing commands and information sent between the control unit and the laser driver signal processor circuit against reverse engineering.
    Type: Grant
    Filed: August 7, 2007
    Date of Patent: December 2, 2008
    Assignee: Mediatek Inc.
    Inventors: Chih-Chin Hsu, Chih-Yuan Chen, Ying-Che Hung