Patent application number | Description | Published |
20100309938 | LASER DRIVING DEVICE AND LASER DRIVING METHOD - 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. | 12-09-2010 |
20110194391 | LASER DEVICE, OPTICAL PICKUP, AND OPTICAL DISK DEVICE - A laser device includes a semiconductor laser, a signal generating circuit generating a pulse signal for driving the semiconductor laser, an amplifying circuit amplifying the pulse signal, and a control circuit unit provided between the amplifying circuit and the semiconductor laser and controlling the pulse signal by letting alternating-current components of the pulse signal pass through and removing at least part of direct-current components of the pulse signal. | 08-11-2011 |
20120044791 | RECORDING APPARATUS - A recording apparatus, which records information in an optical recording medium, includes: a mode-lock laser unit including a saturable absorber section that applies a bias voltage, a gain section that feeds a gain current, a semiconductor laser that emits laser light used to record the information on the optical recording medium, and an external resonator; an optical modulation unit performing amplification modulation on the laser light emitted from the mode-lock laser unit; a reference signal generation unit generating a master clock signal and supplying a signal synchronized with the master clock signal to the gain section of the semiconductor laser; a recording signal generation unit generating a recoding signal based on the master clock signal; and a driving circuit generating a driving pulse used to drive the optical modulation unit based on the recording signal. | 02-23-2012 |
20120063288 | RECORDING APPARATUS - A recording apparatus for recording information on an optical recording medium includes a mode-locked laser unit that includes a semiconductor laser emitting a laser beam for recording the information on the optical recording medium, and an external resonator, an optical modulation unit that amplifies and modulates the laser beam emitted from the mode-locked laser unit, a recording signal generation unit that generates a recording signal based on a reference signal from a drive of the optical recording medium, and a modulation unit that generates a modulation signal for driving the optical modulation unit by latching the recording signal using a laser clock generated by an oscillation pulse of the laser beam emitted from the mode-locked laser unit. | 03-15-2012 |
20130021425 | OPTICAL OSCILLATION DEVICE AND RECORDING APPARATUS - Provided is a recording apparatus including a self-excited oscillation semiconductor laser that has a double quantum well separate confinement heterostructure and includes a saturable absorber section to which a negative bias voltage is applied and a gain section into which a gain current is injected, an optical separation unit, an objective lens, a light reception element, a pulse detection unit, a reference signal generation unit, a phase comparison unit, a recording signal generation unit, and a control unit. | 01-24-2013 |
20130021887 | OPTICAL OSCILLATION DEVICE AND RECORDING APPARATUS - Provided is a recording apparatus including a self-excited oscillation semiconductor laser that has a double quantum well separate confinement heterostructure and includes a saturable absorber section to which a negative bias voltage is applied and a gain section into which a gain current is injected, an optical separation unit, an objective lens, a light reception element, a pulse detection unit, a reference signal generation unit, a phase comparison unit, a recording signal generation unit, and a control unit. | 01-24-2013 |
20130021891 | OPTICAL OSCILLATION DEVICE AND RECORDING APPARATUS - Provided is a recording apparatus including a self-excited oscillation semiconductor laser that has a double quantum well separate confinement heterostructure and includes a saturable absorber section to which a negative bias voltage is applied and a gain section into which a gain current is injected, an optical separation unit, an objective lens, a light reception element, a pulse detection unit, a reference signal generation unit, a phase comparison unit, a recording signal generation unit, and a control unit. | 01-24-2013 |
20130235710 | LIGHT SOURCE AND RECORDING APPARATUS - There is provided a light source including a mode-lock laser unit that includes a semiconductor laser and an external resonator unit and emits a laser beam having a predetermined frequency, the semiconductor laser including a saturable absorber unit that applies a reverse bias voltage and a gain unit that applies a gain current, a semiconductor optical amplifier that performs amplification modulation on the laser beam emitted from the mode-lock laser unit, a laser clock generating unit that generates a laser clock synchronized with the laser beam based on a signal detected from the saturable absorber unit when the laser beam oscillates in the mode-lock laser unit, and a modulating unit that generates a driving current synchronized with the laser clock and applies the driving current to the semiconductor optical amplifier. | 09-12-2013 |