Particular Component Circuitry Patents (Class 372/38.1)
  • Patent number: 8502178
    Abstract: An extreme ultraviolet light source apparatus, in which a target material is irradiated with a laser beam from a laser apparatus and the target material is turned into plasma, thereby emitting extreme ultraviolet light, may include a burst control unit configured to control irradiation of the target material is irradiated with the laser beam outputted successively in pulses from the laser apparatus when the extreme ultraviolet light is emitted successively in pulses. The target material is prevented from being turned into plasma by the laser beam while the laser beam is outputted successively in pulses from the laser apparatus when the successive pulsed emission is paused.
    Type: Grant
    Filed: January 12, 2012
    Date of Patent: August 6, 2013
    Assignee: Gigaphoton Inc.
    Inventors: Masato Moriya, Hideyuki Hayashi, Tooru Abe
  • Patent number: 8483250
    Abstract: A semiconductor laser driving device and an image forming apparatus are disclosed that are capable of accurately detecting the deterioration of the semiconductor laser with a smaller circuit size and regardless of the variation of the characteristics of the semiconductor laser and the use conditions of the semiconductor laser by adding a minimum circuit are disclosed. In the semiconductor laser driving device, the output voltage generated by an operational amplifier circuit by amplifying a voltage difference between a monitoring voltage (Vm) and a predetermined reference voltage (Vref) is transmitted to a bias current generating circuit unit as a bias current setting voltage (Vbi) through a sample/hold circuit having a switch (SW1) and a sample/hold capacitor (Csh). When the bias current setting voltage (Vbi) is greater than a predetermined voltage, a deterioration detecting circuit transmits a deterioration detecting signal indicating that the deterioration of the semiconductor laser is detected.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: July 9, 2013
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiko Kamatani
  • Patent number: 8477815
    Abstract: An apparatus is provided. The apparatus includes a lasing element, a laser driver and logic. The laser driver is configured to drive the lasing element at multiple current levels, and the laser driver includes a switching network, multiple direct current (DC) loops, and an output circuit. The switching network receives a differential input signal, and each DC loop is coupled to the switching network. The output circuit is also coupled to the lasing element, and the logic is coupled to each of the DC current loops, where the logic selects one or more of the DC loops in each (of several) modes. Each mode generates one or more output lasing currents for the lasing element that corresponds to a one or more of the current levels in response to the differential input signal.
    Type: Grant
    Filed: September 7, 2011
    Date of Patent: July 2, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Douglas W. Dean, Jeremy R. Kuehlwein
  • Patent number: 8457499
    Abstract: A semiconductor laser drive apparatus comprises a bias current setting section (232) which sets a bias current value on the basis of the drive temperature so that the temperature characteristic of the bias current value with respect to the drive temperature may be a linear function having a slope except zero and a drive current setting section (233) for setting the drive current value on the basis of the drive temperature so that the temperature characteristic of the drive current value with respect to the drive temperature may be a function having a slope except zero. The temperature characteristic of the bias current and that of the drive current are functions different from each other. With this, low cost, space-saving, and power-saving of a semiconductor laser are achieved, and a semiconductor laser drive apparatus enabling a good transmission characteristic on the reception side and a high optical output over the whole drive temperature range when driving the semiconductor laser can be provided.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: June 4, 2013
    Assignee: OMRON Corporation
    Inventors: Kentaro Hamana, Akira Enami, Yukari Terakawa, Keisuke Uno, Hayami Hosokawa
  • Publication number: 20130092849
    Abstract: A laser device having master oscillators that output seed beams is provided. The seed beams are guided from the master oscillators to a regenerative amplifier such that at least one of the seed beams enters the regenerative amplifier at an angle that differs from an angle at which another seed beam enters the regenerative amplifier. A laser apparatus and an extreme ultraviolet light generation system using the laser device are also provided.
    Type: Application
    Filed: February 27, 2012
    Publication date: April 18, 2013
    Applicant: GIGAPHOTON INC.
    Inventors: Krzysztof Nowak, Osamu Wakabayashi
  • Patent number: 8406263
    Abstract: A laser diode read driver includes a first transistor producing a first voltage in response to receiving a first current signal. A transconductor has a first input coupled to receive the first voltage and produces a second current signal in response to differences between signals received on the first input and a second input. A second transistor is coupled to the second input and produces a third current signal in response to receiving the second current signal. A third transistor is coupled to the second transistor and the second input and produces an output current signal in response to receiving the third current signal. The first transistor is scaled to the first transistor by the inverse of a gain factor. First and second resistors are coupled between the first and third transistors and a low voltage supply, and are scaled to each other by the gain factor.
    Type: Grant
    Filed: August 27, 2012
    Date of Patent: March 26, 2013
    Assignee: Texas Instruments Incorporated
    Inventor: Douglas Warren Dean
  • Patent number: 8406261
    Abstract: A laser driving device includes: a pulse signal generating unit that, after a voltage has risen from a predetermined reference voltage to a predetermined output voltage and a time of a sum of an oscillation period of relaxation oscillation and a light emission start time in a predetermined laser diode has nearly elapsed, generates a pulse signal having a waveform that falls divisionally in two or more stages from the output voltage to the reference voltage; and an output unit that generates a laser drive signal by performing signal processing on the pulse signal and outputs the signal to the laser diode.
    Type: Grant
    Filed: June 2, 2010
    Date of Patent: March 26, 2013
    Assignee: Sony Corporation
    Inventors: Goro Fujita, Tsutomu Maruyama, Seiji Kobayashi
  • Publication number: 20130064258
    Abstract: A master oscillator system may include a grating that functions as one of a plurality of resonator mirrors in an optical resonator, an optical element disposed within an optical path between the plurality of resonator mirrors, and an attitude control mechanism that adjusts an angle at which laser light traveling within the optical resonator is incident on the grating by adjusting the attitude of the optical element.
    Type: Application
    Filed: September 4, 2012
    Publication date: March 14, 2013
    Applicant: Gigaphoton Inc.
    Inventors: Junichi FUJIMOTO, Takahito KUMAZAKI
  • Publication number: 20130064259
    Abstract: A solid-state laser apparatus may include: a master oscillator configured to output laser light having at least one longitudinal mode, the master oscillator being capable of changing the spectral linewidth of the laser light output therefrom; at least one amplifier located downstream of the master oscillator on an optical path; a wavelength converter located downstream of the amplifier on the optical path; a detector configured to detect the spectrum of the laser light; and a controller configured to control the spectral linewidth of the laser light output from the master oscillator based on a detection result of the detector.
    Type: Application
    Filed: November 8, 2012
    Publication date: March 14, 2013
    Applicant: Gigaphoton Inc.
    Inventor: Gigaphoton Inc.
  • Patent number: 8345722
    Abstract: The present invention provides a method of driving a semiconductor laser, where the method can control changes in the internal temperature of a device as well as control optical output using a driving current. A method of driving a semiconductor laser includes steps of: preliminary driving the semiconductor laser by preliminary activating at a current value larger than a threshold value; de-activating the semiconductor laser, after the step of preliminary driving; and starting a formation of a latent image on a photosensitive drum based on a latent image formation signal, after the step of de-activating.
    Type: Grant
    Filed: March 30, 2011
    Date of Patent: January 1, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Takeshi Uchida
  • Publication number: 20120300799
    Abstract: The invention relates to a laser amplification system for generating retrievable laser pulses having at least one laser source, in particular with a pulse selector arranged downstream thereof for the targeted selection of amplifiable laser pulses, a laser medium for amplifying laser pulses generated by the laser source and a loss modulator, wherein the loss modulator is arranged and connected such that said modulator modulates the amplification of the laser pulses by the laser medium by loss generation so that the retrievable laser pulses are provided with a predefined pulse time and/or pulse energy. Before an amplification process for one of the laser pulses, the current amplification of the laser medium is determined and the loss generation is controlled by the loss modulator depending on the current amplification of the laser medium.
    Type: Application
    Filed: February 15, 2011
    Publication date: November 29, 2012
    Applicant: HIGH Q LASER GMBH
    Inventors: Joachim Meier, Maximilian Josef Lederer
  • Patent number: 8310750
    Abstract: A waveform shaping circuit enhances a rise of a waveform of a voltage applied to a load and includes an input unit to which the voltage is input; a supply unit configured to apply the voltage input from the input unit to the load; a first resistor connected in series between the input unit and the supply unit; a second resistor branch-connected to a portion between the input unit and the supply unit; and a stub connected to the first resistor or the second resistor and including a transmission path of a given length configured to shuttle the voltage by transmitting and reflecting the voltage as a voltage wave.
    Type: Grant
    Filed: November 17, 2010
    Date of Patent: November 13, 2012
    Assignee: Fujitsu Limited
    Inventor: Setsuo Yoshida
  • Patent number: 8306080
    Abstract: A surface emitting laser apparatus includes an arithmetic processing unit including an I/O unit for externally inputting an instruction and a core unit that performs an operation based on the instruction and outputs a differential voltage signal modulated with a predetermined amplitude according to a result of the operation, capacitors respectively arranged on output paths of the differential voltage signal, and a surface emitting laser device that is directly connected to the arithmetic processing unit via the capacitors. An I/O voltage and a core voltage are externally supplied to the I/O unit and the core unit, respectively. The arithmetic processing unit generates a driving voltage signal by superimposing the differential voltage signal with the core voltage commonly supplied as a bias voltage without stepping up or down the core voltage and without amplifying the differential voltage signal and supplies the driving voltage signal to the surface emitting laser device.
    Type: Grant
    Filed: April 20, 2011
    Date of Patent: November 6, 2012
    Assignee: Furukawa Electric Co., Ltd.
    Inventors: Keishi Takaki, Naoki Tsukiji, Suguru Imai
  • Patent number: 8300670
    Abstract: A method for deriving precise control over laser power of an optical pickup unit (OPU) includes: providing an analog-to-digital converter (ADC) within an automatic power calibration (APC) circuit to derive a path gain and/or a path offset from the APC circuit; and selectively performing compensation according to the gain and/or the path offset, in order to maintain precision of a relationship between the laser power and a target command utilized for controlling the laser power. An associated APC circuit comprising an ADC and at least one compensation module is further provided. The ADC is utilized for deriving a path gain and/or a path offset from the APC circuit. The compensation module is utilized for selectively performing compensation according to the path gain and/or the path offset, in order to control the laser power by a target command.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: October 30, 2012
    Assignee: Mediatek Inc.
    Inventors: Hsiao-Yuan Chi, Chih-Ching Chen, Chia-Wei Liao
  • Patent number: 8290006
    Abstract: A Dynamically Variable Spot Size (DVSS) laser system for bonding metal components includes an elongated housing containing a light entry aperture coupled to a laser beam transmission cable and a light exit aperture. A plurality of lenses contained within the housing focus a laser beam from the light entry aperture through the light exit aperture. The lenses may be dynamically adjusted to vary the spot size of the laser. A plurality of interoperable safety devices, including a manually depressible interlock switch, an internal proximity sensor, a remotely operated potentiometer, a remotely activated toggle and a power supply interlock, prevent activation of the laser and DVSS laser system if each safety device does not provide a closed circuit. The remotely operated potentiometer also provides continuous variability in laser energy output.
    Type: Grant
    Filed: October 25, 2011
    Date of Patent: October 16, 2012
    Assignee: The United States of America as Represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Paul R. Gradl, John F. Hurst, James R. Middleton
  • Patent number: 8275012
    Abstract: A first transistor produces a first voltage in response to a first current signal. A first resistor is coupled between the first transistor and a low voltage supply. A transconductor has a first input receiving the first voltage and producing a second current signal in response to differences between signals received on the first input and a second input. A second transistor is coupled to the second input and produces a third current signal in response to the second current signal. A third transistor, coupled to the second transistor and the second input, produces an output current signal in response to the third current signal. The first transistor is scaled to the third transistor by the inverse of a gain factor. A second resistor is coupled between the third transistor and a low voltage supply. The first resistor is scaled to the second resistor by the gain factor.
    Type: Grant
    Filed: December 23, 2009
    Date of Patent: September 25, 2012
    Assignee: Texas Instruments Incorporated
    Inventor: Douglas Warren Dean
  • Patent number: 8270444
    Abstract: A side emitting semiconductor package includes a two-sided electric circuit formed on a silicon substrate of the package, and a plurality of semiconductor light emitting devices bonded on two bilateral surfaces of the electric circuit to provide a surface mounted device with two light emitting sides.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: September 18, 2012
    Assignee: Advanced Optoelectronics Technology, Inc.
    Inventors: Min-Tsun Hsieh, Wen-Liang Tseng, Lung-Hsin Chen, Chih-Yung Lin
  • Patent number: 8242709
    Abstract: An optical transmitter includes a light-emitting device and an optical modulator that modulates light output from the light-emitting device by using an input signal. The optical transmitter includes a drive current switching controller that performs an ON/OFF switching control of a drive current of the light-emitting device, by using an ON/OFF signal as an input that controls ON/OFF of an optical output of the light-emitting device, in response to a switching of the ON/OFF signal. The optical transmitter also includes a drive current adjusting and generating unit that detects an ambient temperature, and generates a drive current that is adjusted according to the ambient temperature detected thereby. The drive current switching controller includes a differential circuit that is supplied a drive current that is generated by the drive current adjusting and generating unit and controls the drive current that is output to the light-emitting device, according to the ON/OFF signal.
    Type: Grant
    Filed: July 13, 2007
    Date of Patent: August 14, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masamichi Nogami, Masaki Noda, Naoki Suzuki
  • Patent number: 8179593
    Abstract: An optical-switch drive circuit including a driver unit that generates, in response to a control signal, an on/off signal for driving a semiconductor optical amplifier gate switch, and a buffer unit having a high input impedance and connected between an output terminal outputting the on/off signal and the semiconductor optical amplifier gate switch. In the optical-switch drive circuit the buffer unit may include a high-resistance voltage divider that is connected with the output terminal, and an operational amplifier that buffers, and provides to the semiconductor optical amplifier gate switch, a divided voltage of the voltage divider.
    Type: Grant
    Filed: March 18, 2009
    Date of Patent: May 15, 2012
    Assignee: Fujitsu Limited
    Inventors: Masaji Noguchi, Yutaka Kai, Setsuo Yoshida
  • Patent number: 8165475
    Abstract: A system for reducing clipping may be used between a multichannel RF source and a laser to reduce or correct clipping that might occur in the laser as a result of negative spikes or peaks in a multichannel RF signal. The system generally includes a clipping correction circuit that receives the multichannel RF signal and responsive to the RF signal, prevents one or more of the negative peaks in the RF signal from causing clipping. The clipping correction circuit may either detect an envelope of the RF signal and/or may detect one or more peaks in the RF signal. One or more negative peaks may be prevented from causing clipping by adjusting a bias current provided by a bias control circuit and/or by modifying the RF signal with one or more clipping correction pulses coinciding with one or more negative peaks.
    Type: Grant
    Filed: May 24, 2007
    Date of Patent: April 24, 2012
    Assignee: Applied Optoelectronics
    Inventor: Jun Zheng
  • Patent number: 8152314
    Abstract: A display device (100) of the present invention has a first switch (3) and a second switch (4) on an upper surface of its casing, and includes a control circuit (18) for controlling the first switch (3) and the second switch (4) and a light source (19) inside the casing. The control circuit (18) performs control so that the light source (19) is turned on when the second switch (4) is pressed after a predetermined period of time has passed from when the first switch (3) was pressed. Thereby, the display device (100) of the present invention prevents entering of a person into a projection area before projection of video, and controls inadvertent start-up.
    Type: Grant
    Filed: May 22, 2006
    Date of Patent: April 10, 2012
    Assignee: Panasonic Corporation
    Inventors: Toshifumi Yokoyama, Ken'ichi Kasazumi, Shin-ichi Kadowaki, Kiminori Mizuuchi, Hiroyuki Furuya, Kazuhisa Yamamoto
  • Patent number: 8098699
    Abstract: A semiconductor laser apparatus comprises a first semiconductor laser device that emits a blue-violet laser beam, a second semiconductor laser device that emits a red laser beam, and a conductive package body. The first semiconductor laser device has a p-side pad electrode and an n-side electrode. The p-side pad electrode and n-side electrode of the first semiconductor laser device are electrically isolated from the package body. The p-side pad electrode of the first semiconductor laser device is connected with a drive circuit that generates a positive potential, while the n-side electrode thereof is connected with a dc power supply that generates a negative potential.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: January 17, 2012
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Daijiro Inoue, Yasuyuki Bessho, Masayuki Hata, Yasuhiko Nomura
  • Patent number: 8077750
    Abstract: An optical transmitting module of a coaxial type is provided in which a disturbance in a waveform of light which is output from a semiconductor laser element due to a signal which is output from an optical modulator unit can be suppressed. The optical transmitting module comprises an optical transmitting package of a coaxial type and a line board (40) connected to the optical transmitting package. The optical transmitting package comprises a semiconductor laser element, an optical modulator unit, and a conductor board (21). A drive current supply line (42) and a common ground line are formed over the line board (40), and a signal attenuation circuit (60) having one end electrically connected to the common ground line and the other end electrically connected to the drive current supply line (42) is provided over the line board (40).
    Type: Grant
    Filed: January 23, 2009
    Date of Patent: December 13, 2011
    Assignee: OpNext Japan, Inc.
    Inventors: Masahiro Hirai, Hiroshi Yamamoto
  • Publication number: 20110274128
    Abstract: A cylindrical lens (4) diverges a laser beam (L1) in the Y-axis direction (i.e., within the YZ plane) but neither diverges nor converges it in the X-axis direction (i.e., within the ZX plane). An objective lens (5) converges the laser beam (L1) emitted from the cylindrical lens (4) into a point P1 in the Y-axis direction and into a point P2 in the X-axis direction. As a consequence, the cross section of the laser beam (L1) becomes elongated forms extending in the X- and Y-axis directions at the points P1, P2, respectively. Therefore, when the points P1, P2 are located on the outside and inside of the work (S), respectively, an elongated working area extending in the Y-axis direction can be formed in a portion where the point P2 is positioned within the work (S).
    Type: Application
    Filed: December 4, 2009
    Publication date: November 10, 2011
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Kenshi Fukumitsu, Shingo Oishi, Shinichiro Aoshima
  • Patent number: 8040930
    Abstract: A drive circuit for driving a semiconductor light emitting element includes a board, a first pattern formed in a first layer of the board so as to be electrically connected to an anode of the semiconductor light emitting element, and a second pattern formed in a second layer of the board so as to be electrically connected to a cathode of the semiconductor light emitting element, and the first pattern and the second pattern are formed so as to overlap with each other when viewed in a direction along a normal line of the board.
    Type: Grant
    Filed: August 12, 2008
    Date of Patent: October 18, 2011
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhisa Mizusako, Kiyoto Sudo
  • Patent number: 8036254
    Abstract: The output voltage of a cathode drive-type semiconductor laser driving circuit is set to a minimum, power consumption by a driving circuit portion is suppressed, and the heat that is generated by the optical head or the optical disc device is reduced. In addition to a conventional configuration, the semiconductor laser driving circuit of the invention measures the cathode voltage (Vout) of a semiconductor laser (1) and controls the anode voltage (Vld) such that the cathode voltage (Vout) becomes a predetermined level, and by doing so sets the output voltage of the semiconductor laser driving circuit to a predetermined level in order to curtail power consumption by the driving circuit and minimize the rise in temperature of the optical head or the optical disc device.
    Type: Grant
    Filed: June 14, 2006
    Date of Patent: October 11, 2011
    Assignee: Panasonic Corporation
    Inventors: Kenzo Ishibashi, Hisashi Senga, Takeharu Yamamoto
  • Patent number: 8009709
    Abstract: A DC coupled driver is described for modulating a vertical cavity surface emitting laser at high speeds with active termination. High speed and low total power dissipation is achieved by improving the driver immunity to pulse reflections, which can arise due to impedance mismatch between the driver output impedance and the VCSEL impedance. The rise and fall times of the driver may be adjusted for particular applications. The driver may be fabricated using a choice of bipolar, NMOS and PMOS technologies.
    Type: Grant
    Filed: April 27, 2009
    Date of Patent: August 30, 2011
    Assignee: JDS Uniphase Corporation
    Inventor: David A. Nelson
  • Patent number: 8008615
    Abstract: A beam power source transmits a signal indicating power availability, receives a request for power in response, and beams power in response to the request.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: August 30, 2011
    Assignee: The Invention Science Fund I, LLC
    Inventors: Roderick A. Hyde, Muriel Y. Ishikawa, Jordin T. Kare, Thomas J. Nugent, Jr., Thomas A. Weaver, Lowell L. Wood, Jr., Victoria Y. H. Wood
  • Patent number: 8000361
    Abstract: The higher efficiency and lower power consumption are realized in a laser system for generating a high-power short-pulse laser beam. The laser system includes a laser oscillator for generating a pulse laser beam by laser oscillation, plural amplifiers for sequentially inputting the pulse laser beam generated by the laser oscillator and amplifying the pulse laser beam, and a control unit for controlling the laser oscillator to perform burst oscillation and halting an amplification operation of at least one of the plural amplifiers in a burst halt period between burst oscillation periods.
    Type: Grant
    Filed: March 9, 2009
    Date of Patent: August 16, 2011
    Assignees: Komatsu Ltd., Gigaphoton Inc.
    Inventors: Tamotsu Abe, Hideo Hoshino, Akira Endo, Osamu Wakabayashi, Kouji Kakizaki
  • Patent number: 8000370
    Abstract: A laser-induced optical wiring apparatus includes a substrate, first and second light-reflecting members provided on the substrate separately from each other, an optical waveguide provided on the substrate for optically coupling the first and second light-reflecting members to form an optical resonator, a first optical gain member provided across the optical waveguide and forming a laser oscillator along with the first and second light-reflecting members, and a second optical gain member provided across the optical waveguide separately from the first optical gain member, and forming another laser oscillator along with the first and second light-reflecting members.
    Type: Grant
    Filed: July 13, 2010
    Date of Patent: August 16, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hideto Furuyama
  • Patent number: 7995630
    Abstract: This invention relates to opto-electronic systems using semiconductor lasers driven by optical phase-locked loops that control the laser's optical phase and frequency. Feedback control provides a means for precise control of optical frequency and phase, including the ability for broadband electronic tunability of optical signals and the cascading of multiple lasers for enhanced tunability and coherent combining for increased output power.
    Type: Grant
    Filed: April 1, 2009
    Date of Patent: August 9, 2011
    Inventor: George A. Rakuljic
  • Patent number: 7991031
    Abstract: In a method of controlling an injection-seeded laser, a response of the laser is sampled at a plurality of different laser current values. A threshold current and a slope efficiency of the sampled response are then estimated, and a bias current and a modulation current calculated based on the estimated threshold current and a slope efficiency.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: August 2, 2011
    Assignee: LG-Ericsson Co., Ltd.
    Inventor: John D. Bainbridge
  • Patent number: 7991030
    Abstract: A method for deriving precise control over laser power of an optical pickup unit (OPU) includes: providing an analog-to-digital converter (ADC) within an automatic power calibration (APC) circuit to derive a path gain and/or a path offset from the APC circuit; and selectively performing compensation according to the gain and/or the path offset, in order to maintain precision of a relationship between the laser power and a target command utilized for controlling the laser power. An associated APC circuit comprising an ADC and at least one compensation module is further provided. The ADC is utilized for deriving a path gain and/or a path offset from the APC circuit. The compensation module is utilized for selectively performing compensation according to the path gain and/or the path offset, in order to control the laser power by a target command.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: August 2, 2011
    Assignee: Mediatek Inc.
    Inventors: Hsiao-Yuan Chi, Chih-Ching Chen, Chia-Wei Liao
  • Patent number: 7986720
    Abstract: A circuit for driving a light-emitting element such as a laser diode LD has a boost circuit for boosting an input voltage to supply it to the light-emitting element, a photoreceptor such as a photodiode PD for monitoring light from the light-emitting element; and a boost control circuit for controlling a boost voltage of the boost circuit based on a monitored amount of the photoreceptor. In the method for driving a light-emitting element by boosting an input voltage to supply the voltage to the light-emitting element, light from the light-emitting element is monitored and its monitored amount is used as a basis to control a boost voltage to the light-emitting element. A control circuit may be provided to control a driving current that passes through the light-emitting element based on the monitored amount of the photoreceptor.
    Type: Grant
    Filed: June 25, 2009
    Date of Patent: July 26, 2011
    Assignee: NEC Corporation
    Inventor: Masashi Tachigori
  • Patent number: 7972877
    Abstract: A method of fabricating a light emitting diode package structure is provided. First, a first circuit substrate having a first surface and a corresponding second surface and a second circuit substrate having a third surface and a corresponding fourth surface are provided. The second surface and the third surface respectively have a plurality of electrodes. Then, a plurality of N-type semiconductor materials and a plurality of P-type semiconductor materials alternatively arranged on the electrodes are formed. Then, the first circuit substrate and the second circuit substrate are assembled. The two type semiconductor materials are located between the electrodes of the first circuit substrate and the second circuit substrate. The two type semiconductor materials are electrically connected to the first circuit substrate and the second circuit substrate through the electrodes. Finally, an LED chip is arranged on the first surface and electrically connected to the first circuit substrate.
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: July 5, 2011
    Assignee: Industrial Technology Research Institute
    Inventors: Ming-Ji Dai, Chun-Kai Liu, Chih-Kuang Yu
  • Patent number: 7949025
    Abstract: A controller (320) for controlling various operational parameters of the Laser Module (303). The modulation drive signal (300) causes the circuits in the driver (301) to send a signal to the output (302) so that the laser can send an optical power output (304) proportional to the drive signal (300). The control methods in Laser Controller IC (320) consist of control algorithms embedded in firmware. The Laser Controller IC (320) includes support circuits for control of a laser. Some of the distinguishing features in the present invention are 1) feedback information from the sensors is obtained in a synchronous manner as a snapshot of the laser performance, and 2) algorithms handle the entire set of controls in firmware. The algorithm feature allows for advanced servo controls, which precisely stabilize the laser, can accommodate adaptive controls, and can be leveraged from one laser transmitter design to another.
    Type: Grant
    Filed: December 21, 2002
    Date of Patent: May 24, 2011
    Assignee: Tecey Software Development KG, LLC
    Inventor: Jorge Sanchez Olea
  • Patent number: 7920265
    Abstract: In a modulated optical reflectance (MOR) system, a laser noise suppression technique utilizes a reference beam split optically from a probe laser prior to injection of a beam from the probe laser into an MOR signal path. The reference beam and a probe beam reflected from the sample are sent to first and second detectors, which produce first and second signals. A signal combiner receives the second signal at a first input and produces a combiner signal that corresponds to a difference between signals applied to the first and a second input. A level balancer receives the first signal and a signal derived from the combiner signal and produces a balancer output that is coupled to the second input of the signal combiner. The combination of the balancer output and the second signal tends to cancel out an average value of the second signal from the combiner signal.
    Type: Grant
    Filed: July 29, 2008
    Date of Patent: April 5, 2011
    Assignee: KLA-Tencor Corporation
    Inventor: Alan George
  • Patent number: 7916765
    Abstract: A control circuit for a laser diode is disclosed, in which the driving current may be suppressed even when the monitor PD breaks down to make the APC feedback control inoperable. The control circuit comprises an LD driver to supply the driving current to the LD, a monitor PD to detect a portion of output light from the LD, and the APC controller to adjust the driving current. The current limiter, when the driving current reaches or exceeds the threshold, controls the driving current Id so as to keep the current in a preset value or a value just before the extraordinary increase of the driving current occurs.
    Type: Grant
    Filed: August 5, 2008
    Date of Patent: March 29, 2011
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Takeshi Irie
  • Patent number: 7903703
    Abstract: The present invention provides a control device capable of performing feedback control so that a signal-wavelength input to a control target object becomes a specific signal-wavelength, using an input signal whose duty value is other than 50%. Accordingly, the control device according to the present invention is a control device for performing feedback control so that a signal-wavelength input to a control target object (500) becomes a specific signal-wavelength, the control device including a control unit (100) that performs feedback control so that the signal-wavelength input to the control target object (500) becomes the specific signal-wavelength, using an input signal input to the control target object (500), the input signal whose duty value is other than 50%.
    Type: Grant
    Filed: March 13, 2008
    Date of Patent: March 8, 2011
    Assignee: NEC Corporation
    Inventor: Xingzhou Xu
  • Patent number: 7899098
    Abstract: A laser diode driver IC of a transmitter or transceiver is provided with circuitry for monitoring the forward voltage of the laser diode or laser diodes of the transmitter or transceiver to enable the health of the laser diode or diodes to be assessed in real-time.
    Type: Grant
    Filed: November 25, 2008
    Date of Patent: March 1, 2011
    Assignee: Avago Technologies Fiber IP (Singapore) Pte. Ltd.
    Inventors: Michael A. Robinson, Laura Giovane, An-Nien Cheng
  • Publication number: 20110044741
    Abstract: A laser fixing apparatus includes a laser light generator that generates laser light to be projected onto a recording medium; and a first condenser that reflects and condenses light reflected at an irradiation position of the laser light, such that the reflected light reenters at the irradiation position or near the irradiation position. The first condenser has a concave cylindrical surface and is arranged such that a center axis position of the cylindrical surface is located at the irradiation position of the laser light or near the irradiation position, and a reflecting surface of the first condenser is covered by a light transmitting body.
    Type: Application
    Filed: February 15, 2010
    Publication date: February 24, 2011
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Takashi MATSUBARA, Makoto FURUKI, Naoyuki EGUSA, Tetsuro KODERA, Miho WATANABE
  • Patent number: 7885540
    Abstract: Techniques for measuring optical modulation amplitude (OMA) are disclosed. For example, a technique for measuring an OMA value associated with an input signal includes the following steps/operations. The input signal is applied to a photodetector, wherein the photodetector is calibrated to have a given responsivity value R, and further wherein the photodetector generates an output signal in response to the input signal. The output signal from the photodetector is applied to a radio frequency (RF) power meter, wherein the RF power meter measures the root mean squared (RMS) power value of the output signal received from the photodetector. The OMA value associated with the input signal is determined in response to the root mean squared (RMS) power value measured by the RF power meter. The OMA value may be determined as a function of a factor F derived from a relationship between an amplitude of a data signal and the RMS value of the data signal.
    Type: Grant
    Filed: May 2, 2008
    Date of Patent: February 8, 2011
    Assignee: International Business Machines Corporation
    Inventors: Casimer DeCusatis, Daniel M. Kuchta, Jeremy Daniel Schaub
  • Patent number: 7869479
    Abstract: An optical module includes a stem; a first lead pin and a second lead pin for receiving differential signals, the first and second lead pins penetrating the stem; a mount block fixed to the stem; a laser diode having a pair of electrodes; a submount mounted on the mount block and having an interdigital capacitor, and a plurality of electrode patterns on a surfaces on the submount; and a first wire and a second wire electrically connecting the submount to the first and second lead pins, respectively. The laser diode is mounted on one of the electrode patterns on the submount and connected to another one of the electrode patterns on the submount by a third wire such that the laser diode and the interdigital capacitor form an electrical circuit. The interdigital capacitor has a capacitance selected to reduce signal reflection at a selected frequency.
    Type: Grant
    Filed: January 23, 2008
    Date of Patent: January 11, 2011
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hiroshi Aruga
  • Patent number: 7868999
    Abstract: A lithographic apparatus is disclosed that has a plurality of control circuits, each control circuit arranged to be connected to an associated radiation source of a plurality of radiation sources configured to generate pulses of radiation for projection onto a substrate and each control circuit arranged to control the energy of radiation pulses generated by that associated radiation source.
    Type: Grant
    Filed: August 10, 2006
    Date of Patent: January 11, 2011
    Assignee: ASML Netherlands B.V.
    Inventors: Johannes Heintze, Erik Petrus Buurman, Mark Trentelman
  • Patent number: 7856039
    Abstract: In a semiconductor device, a switching current generator circuit generates and outputs a switching current such that a voltage input to a switching current setting terminal is equal to a voltage input to a switching current control terminal, and a bias current generator circuit generates and outputs a bias current such that a voltage input to a bias current setting terminal equals a voltage input to a bias current control terminal. A memory circuit inputs a voltage according to an amount of light emitted by a semiconductor laser, and generates a voltage to make the input voltage equal to a predetermined first reference voltage corresponding to a predetermined amount of light. An APC output terminal outputs the voltage output by the memory circuit to an external device. A current adding circuit combines the switching current and the bias current to generate a drive current to drive the semiconductor device.
    Type: Grant
    Filed: December 1, 2008
    Date of Patent: December 21, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiko Kamatani
  • Patent number: 7835412
    Abstract: A control system for a laser source driven by a direct current drive voltage includes a system control board, a laser driver, and a power stabilizing circuit. The system control board is configured to output a control signal based on input data. The laser driver is coupled to the laser source and to the system control board. The laser driver is configured to drive the laser source with the drive voltage to generate a laser beam modulated according to the control signal. The power stabilizing circuit is configured to regulate the drive voltage to a given constant level. The power stabilizing circuit includes a first circuit and a second circuit. The first circuit is configured to boost the drive voltage to a level exceeding the given constant level. The second circuit is configured to limit the boosted drive voltage to the given constant level.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: November 16, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Yasuhiro Abe
  • Patent number: 7830933
    Abstract: An optical transmitter with a plurality of transmitter units each providing a Peltier device is disclosed. The Peltier devices of the invention are connected in series with respect to the driver, accordingly, even when the Peltier devices show a relative low impedance, a total load impedance viewed from the driver becomes a substantial value and the total power consumption of the transmitter may be reduced.
    Type: Grant
    Filed: June 16, 2008
    Date of Patent: November 9, 2010
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Tomoyuki Funada
  • Patent number: 7801193
    Abstract: A laser diode module with an adjustable monitoring current, wherein the photo diodes monitoring the light-emitting power of the laser diode are arranged in array, and wherein a programmed photo diode is formed by the photo diodes in match of a memory and switch control unit. In this way, the problem of an inconstant monitoring current of the prior art is avoided. Meanwhile, an adjustable monitoring current is achieved.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: September 21, 2010
    Assignee: Arima Lasers Corporation
    Inventor: Hsien-Cheng Yen
  • Patent number: 7796659
    Abstract: Pickup head circuits with a protection circuit capable of preventing unexpected large current flowing through a laser diode during power-on interval. A driving transistor is coupled between a laser diode and a first power voltage, an automatic laser power control (ALPC) circuit is coupled between the first power voltage and a second power voltage, controlling the driving transistor to drive the laser diode. A protection circuit is coupled between the power voltage and a control terminal of the driving transistor, forcing a voltage at the control terminal of the driving transistor to follow the first power voltage during a power-on interval.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: September 14, 2010
    Assignee: Mediatek Inc.
    Inventors: Chin-Tui Chien, Chien-Ming Chen
  • Patent number: RE43685
    Abstract: A system contains a laser output measurement circuit used in a laser control system (210). The circuits contain a photodiode sensor (109), sample and hold amplifier (202), IC with synchronizer and delay circuits (206), and an analog to digital converter (204). The circuits measure the laser light output (107) while the laser Module (106) transmits signals. The measurement circuit tracks and stores the laser light output (107) signal using a Photodiode Sensor (109) and with a Sample/hold (202). The methods calculate the value of the laser light output (107) from mathematical relationships, which correlate the light output (107) of the laser Module (106) to the current value of the drive signal (100). Some of the distinguishing features in the present invention are 1) feedback information from the photodiode is obtained in a synchronous manner as a snapshot of the laser performance, and 2) the measurements are precise and calibrated, and 3) no disruption of the signal transmission occurs.
    Type: Grant
    Filed: January 8, 2003
    Date of Patent: September 25, 2012
    Assignee: Tecey Software Development KG, LLC
    Inventor: Jorge Sanchez