Patent application number | Description | Published |
20090021238 | OPTICAL DEVICE AND METHOD OF CONTROLLING THE SAME - An optical device includes an optical element, a detector and a controller. The optical element has an optical waveguide. Refractive index of the optical waveguide is controlled by a heater. A temperature of the optical element is controlled by a temperature control device. The detector detects a current flowing in the heater and/or a voltage applied to the heater. The controller controls an electrical power provided to the heater so as to be kept constant according to the detection result of the detector. | 01-22-2009 |
20090022185 | METHOD OF CONTROLLING SEMICONDUCTOR LASER - A method of controlling a semiconductor laser having a wavelength selection portion, a refractive index of the wavelength selection portion being controllable with a heater including: a starting sequence including a first step for adjusting a heat value of the heater until the heat value of the heater reaches a given value; and a wavelength control sequence including a second step for correcting a wavelength of the semiconductor laser according to a detection result of an oscillation wavelength of the semiconductor laser after the starting sequence. | 01-22-2009 |
20090022186 | METHOD OF CONTROLLING SEMICONDUCTOR LASER - A method of controlling a semiconductor laser that has a plurality of wavelength selection portions having a different wavelength property from each other and is mounted on a temperature control device, including: a first step of correcting a temperature of the temperature control device according to a detected output wavelength of the semiconductor laser; and a second step of controlling at least one of the wavelength selection portions so that changing amount differentials between each wavelength property of the plurality of the wavelength selection portions is reduced, the changing amount differential being caused by correcting the temperature of the temperature control device. | 01-22-2009 |
20090103585 | Optical semiconductor element and optical semiconductor device - An optical semiconductor device includes an optical semiconductor element, a metal pattern and at least one thermal conductive material. The optical semiconductor element has a first optical waveguide region and a second optical waveguide region. The second optical waveguide region is optically coupled to the first optical waveguide region and has a heater for changing a refractive index of the second optical waveguide region. The metal pattern is provided on an area to be thermally coupled to a temperature control device. The thermal conductive material couples the metal pattern with an upper face of the first optical waveguide region of the optical semiconductor element. The thermal conductive material is electrically separated from the first optical waveguide region. | 04-23-2009 |
20090168817 | TESTING METHOD OF WAVELENGTH-TUNABLE LASER, CONTROLLING METHOD OF WAVELENGTH-TUNABLE LASER AND LASER DEVICE - A testing method of a wavelength-tunable laser having a resonator including wavelength selection portions having wavelength property different from each other includes a first step of controlling the wavelength-tunable laser so as to oscillate at a given wavelength according to an initial setting value, a second step of tuning the wavelength property of the wavelength selection portions and detecting discontinuity point of gain-condition-changing of the wavelength-tunable laser, and a third step of obtaining a stable operating point of the wavelength selection portion according to a limiting point of an oscillation condition at the given wavelength, the limiting point being a point when the discontinuity point is detected. | 07-02-2009 |
20100034224 | TUNABLE LASER MODULE, TUNABLE LASER APPARATUS AND CONTROLLING METHOD FOR TUNABLE LASER - A tunable laser module includes a tunable laser section including a gain medium and a wavelength filter having a periodic characteristic which brings about a discontinuous variation of an oscillation wavelength, and a monitoring section adapted to output a monitoring signal which periodically varies in response to the oscillation wavelength of the tunable laser section. The monitoring section includes a monitoring wavelength filter having a periodic characteristic which defines the monitoring signal. The relationship between the period of the wavelength filter and the period of the monitoring wavelength filter is set such that the monitoring signal varies when the oscillation wavelength varies discontinuously. | 02-11-2010 |
20100040101 | Optical Semiconductor Device - An optical semiconductor device has a semiconductor substrate, a semiconductor region and heater. The semiconductor region has a stripe shape demarcated with a top face and a side face thereof. The stripe shape has a width smaller than a width of the semiconductor substrate. An optical waveguide layer is located in the semiconductor region. A distance from a lower end of the side face of the semiconductor region to the optical waveguide layer is more than half of the width of the semiconductor region. The heater is provided above the optical waveguide layer. | 02-18-2010 |
20100091805 | OPTICAL SEMICONDUCTOR ELEMENT AND OPTICAL SEMICONDUCTOR DEVICE - An optical semiconductor device includes an optical semiconductor element, a metal pattern and at least one thermal conductive material. The optical semiconductor element has a first optical waveguide region and a second optical waveguide region. The second optical waveguide region is optically coupled to the first optical waveguide region and has a heater for changing a refractive index of the second optical waveguide region. The metal pattern is provided on an area to be thermally coupled to a temperature control device. The thermal conductive material couples the metal pattern with an upper face of the first optical waveguide region of the optical semiconductor element. The thermal conductive material is electrically separated from the first optical waveguide region. | 04-15-2010 |
20120097984 | OPTICAL SEMICONDUCTOR DEVICE, LASER CHIP AND LASER MODULE - An optical semiconductor device has a semiconductor substrate, an optical semiconductor region and a heater. The optical semiconductor region is provided on the semiconductor substrate and has a width smaller than that of the semiconductor substrate. The heater is provided on the optical semiconductor region. The optical semiconductor region has a cladding region, an optical waveguide layer and a low thermal conductivity layer. The optical waveguide layer is provided in the cladding region and has a refractive index higher than that of the cladding region. The low thermal conductivity layer is provided between the optical waveguide layer and the semiconductor substrate and has a thermal conductivity lower than that of the cladding region. | 04-26-2012 |