Patent application number | Description | Published |
20080279234 | Alignment of lasing wavelength with wavelength conversion peak using modulated wavelength control signal - According to one embodiment of the present invention, a programmable light source comprises one or more semiconductor lasers, a wavelength conversion device, and a laser controller. The controller is programmed to operate the semiconductor laser using a modulated feedback control signal. The wavelength control signal is adjusted based on the results of a comparison of a detected intensity signal with a feedback signal to align the lasing wavelength with the conversion efficiency peak of the wavelength conversion device. Laser controllers and projections systems operating according to the control concepts of the present invention are also provided. | 11-13-2008 |
20090086775 | Laser source with interdigital heater electrodes and underlying current confinement layer - A semiconductor laser source is provided wherein the wavelength selective section of the laser diode comprises a P+ type current confinement layer and first and second sets of interdigital heater electrodes formed over the current confinement layer. Individual electrode digits of the first and second sets of interdigital heater electrodes alternate in succession along a direction of optical propagation defined by the active waveguide layer of the laser diode. The first set of interdigital heater electrodes are positively or negatively biased relative to the laser diode cathode and relative to the second set of interdigital heater electrodes such that the relative bias is either less than the forward bias turn-on voltage of the P-N junction or has an absolute value less than the reverse break-down voltage of the P-N junction. | 04-02-2009 |
20090252187 | Minimizing Power Variations In Laser Sources - The present invention relates generally to semiconductor lasers and laser projection systems. According to one embodiment of the present invention, a projected laser image is generated utilizing an output beam of the semiconductor laser. A gain current control signal is generated by a laser feedback loop to control the gain section of the semiconductor laser. Wavelength fluctuations of the semiconductor laser are narrowed by incorporating a wavelength recovery operation in a drive current of the semiconductor laser and by initiating the wavelength recovery operations as a function of the gain current control signal or an optical intensity error signal. Additional embodiments are disclosed and claimed. | 10-08-2009 |
20100002736 | Wavelength normalization in phase section of semiconductor lasers - Particular embodiments of the present invention relate generally to semiconductor lasers and laser projections systems and, more particularly, to schemes for controlling semiconductor lasers. According to one embodiment of the present invention, a laser having a gain section, a phase section and a wavelength selective section is configured for optical emission of encoded data. The optical emission is shifted across a plurality of laser cavity modes by applying a quasi-periodic phase shifting signal I/V | 01-07-2010 |
20100103967 | CORRECTION OF POWER VARIATIONS IN LASER SOURCES - The present invention relates generally to semiconductor lasers and laser projection systems. According to one embodiment of the present invention, a method of correcting output power variations in a semiconductor laser is provided. According to the method, an output power feedback loop is utilized to generate optical intensity feedback signals representing actual output power of the laser source for discrete portions V | 04-29-2010 |
20100250166 | Methods And Devices For Evaluating The Operating Characteristics Of A DBR Laser Diode - In accordance with one embodiment of the present disclosure, a method of evaluating the operating characteristics of a DBR laser diode is provided. According to the method, a diagnostic electrical current is injected into the wavelength tuning section of the DBR laser to generate amplified spontaneous emission of light in the wavelength tuning section. Light emitted from the wavelength tuning section is absorbed by the gain section and photo current generated by the light absorbed in the gain section is measured. The photo current measured in the gain section can be correlated with an evaluation of the operating characteristics of the DBR laser diode. For example, the measured photo current can be correlated with a substandard operating characteristic when it departs from a given photo current metric by more than an acceptable amount. Alternatively, the measured photo current can be correlated with a certified operating characteristic when it departs from the given photo current metric by an acceptable amount. Additional embodiments are disclosed and claimed. | 09-30-2010 |
20100265982 | Fracture Resistant Metallization Pattern For Semiconductor Lasers - Metallization patterns are provided to reduce the probability of chip fracture in semiconductor lasers. According to one embodiment disclosed herein, the pad edges of a metallization pattern extend across a plurality of crystallographic planes in the laser substrate. In this manner, cracks initiated at any given stress concentration would need to propagate across many crystallographic planes in the substrate to reach a significant size. Additional embodiments of the present disclosure relate to the respective geometries and orientations of adjacent pairs of contact pads. Still further embodiments are disclosed and claimed. | 10-21-2010 |
20100322272 | Minimizing power variations in laser sources - The present invention relates generally to semiconductor lasers and laser projection systems. According to one embodiment of the present invention, a projected laser image is generated utilizing an output beam of the semiconductor laser. A gain current control signal is generated by a gain current feedback loop to control the gain section of the semiconductor laser. Wavelength fluctuations of the semiconductor laser are narrowed by incorporating a wavelength recovery operation in a drive current of the semiconductor laser and by initiating the wavelength recovery operations as a function of the gain current control signal or an optical intensity error signal. Additional embodiments are disclosed and claimed. | 12-23-2010 |
20110044359 | Intracavity Conversion Utilizing Narrow Band Reflective SOA - An external cavity laser source is provided comprising an external laser cavity, a tunable distributed Bragg reflector (DBR), a DBR tuning element, an output reflector, a semiconductor optical amplifier (SOA), a frequency-selective optical coupler/reflector, and a wavelength conversion device. The tunable DBR, the DBR tuning element, the SOA, and the output reflector are configured to generate a fundamental laser signal characterized by a fundamental bandwidth that is narrower than the QPM bandwidth of the wavelength conversion device and can be tuned to a fundamental center wavelength within the QPM bandwidth. The frequency-selective optical coupler/reflector is configured for substantially non-reflective two-way transmission of optical signals at the fundamental center wavelength and is further configured for substantially complete reflection of wavelength-converted optical signals generated by the wavelength conversion device. The output reflector is configured for substantially non-reflective transmission of wavelength-converted optical signals generated by the wavelength conversion device and for substantially complete reflection of optical signals at the fundamental center wavelength. Additional embodiments are disclosed and claimed. | 02-24-2011 |
20110205619 | Wavelength Conversion Device With Microlens And Optical Package Incorporating The Same - An optical package is provided comprising a laser diode and a wavelength conversion device. The laser diode and the wavelength conversion device define an external laser cavity and the wavelength conversion device is tilted relative to the output face of the laser diode to define a tilt angle φ that is less than approximately 85°. The input face of the wavelength conversion device comprises a pair of tapered facets and a microlens. The pair of tapered facets and the microlens are defined on the input face such that they share respective portions of the facial waveguide region on the input face, with the tapered facets occupying peripheral portions of the facial waveguide region on the input face and the microlens occupying an interior portion of the facial waveguide region on the input face. Each of the pair of tapered facets define a facet angle α within the facial waveguide region that is less than the facet angle α and is greater than approximately 45°. Additional embodiments are disclosed and claimed. | 08-25-2011 |
20110255567 | Laser Diodes Comprising QWI Output Window and Waveguide Areas and Methods of Manufacture - In accordance with one embodiment of the present disclosure, a process of manufacturing a semiconductor laser diode comprising a gain section, a QWI output window, and QWI waveguide areas is provided. The QWI waveguide areas are fabricated using quantum well intermixing and define a QWI waveguide portion in the QWI output window of the laser diode. The QWI output window is transparent to the lasing wavelength λ | 10-20-2011 |