Patent classifications
H01S5/06233
Addressable vertical cavity surface emitting laser array for generating structured light patterns
An addressable vertical cavity surface emitting laser (VCSEL) array may generate structured light in dot patterns. The VCSEL array includes a plurality of traces that control different groups of VCSELs, such that each group of VCSELs may be individually controlled. The VCSEL groups are arranged such that they emit a dot pattern, and by modulating which groups of VCSELs are active a density of the dot pattern may be adjusted. The VCSEL array may be part of a depth projector that projects the dot pattern into a local area. A projection assembly may replicate the dot pattern in multiple tiles.
LINE BEAM LIGHT SOURCE, LINE BEAM IRRADIATION DEVICE, AND LASER LIFT OFF METHOD
A line beam irradiation apparatus (1000) includes a work stage (200), a line beam source (100) for irradiating a work (300) placed on the work stage (200) with a line beam; and a transporting device (250) for moving at least one of the work stage (200) and the line beam source (100) such that an irradiation position of the line beam on the work moves in a direction transverse to the line beam. The line beam source includes a plurality of semiconductor laser devices and a support for supporting the plurality of semiconductor laser devices. The plurality of semiconductor laser devices are arranged along a same line extending in a fast axis direction, and the laser light emitted from emission regions of respective ones of the semiconductor laser devices diverge parallel to the same line to form the line beam.
METHOD FOR REDUCING SELF-MIXING INTERFERENCE EFFECT OF LASER SYSTEM
The present invention discloses a method for reducing a self-mixing interference effect of a laser system, comprising the following step: connecting a direct current (DC) bias circuit and a modulated signal generator to electrodes of a laser, respectively. The DC bias circuit is configured to drive the laser and provide carriers for pumping to the laser; a resonant cavity is provided in the laser, and is configured to convert the carriers for pumping into photons which are subjected to stimulated radiation to form stable laser output; the DC bias circuit and the modulated signal generator are injected into the laser; the modulated signal generator outputs a modulated signal; and the modulated signal matches a parasitic parameter of the laser so as to change the distribution state of the photons in the resonant cavity of the laser. The present invention spatially and temporally reduces power fluctuation of a laser within a short period of time caused by the self-mixing interference effect, ensures the stability of the whole laser system, and has the advantages of low cost, easy assembly and adjustment, and stable performance.
Drive apparatus that drives light emitting device
A drive apparatus includes a light emitting device, a light receiving device configured to receive light emitted by the light emitting device, a comparison circuit configured to compare a light quantity of light detected by the light receiving device with a target value indicating a light quantity of light to be emitted by the light emitting device and generate a control signal corresponding to a comparison result, and a drive circuit configured to supply a drive signal corresponding to the control signal to the light emitting device. The drive circuit includes a gain changing switch configured to change, in accordance with the target value, a gain of the drive circuit.
CONTROLLING BEAM DIVERGENCE IN A VERTICAL-CAVITY SURFACE-EMITTING LASER
In some implementations, a vertical cavity surface emitting laser (VCSEL) includes a substrate layer and epitaxial layers on the substrate layer. The epitaxial layers may include an active layer, a first mirror, a second mirror, and one or more oxidation layers. The active layer may be between the first mirror and the second mirror, and the one or more oxidation layers may be proximate to the active layer. The one or more oxidation layers may be configured to control beam divergence of a laser beam emitted by the VCSEL based on at least one of: a quantity of the one or more oxidation layers, a shape of the one or more oxidation layers, a thickness of the one or more oxidation layers, or a proximity of the one or more oxidation layers to the active layer.
METHOD FOR GENERATING RANDOM NUMBERS
Provided for herein is a method for generating random numbers, the method includes driving, using a power source and a controller controlling the power source, a surface emitting laser in direct modulation mode, wherein the direct modulation mode is controlled by the controller so that the surface emitting laser is alternately driven below and above the lasing threshold so that laser pulses are emitted from the surface emitting laser, wherein, for driving the surface emitting laser above the lasing threshold, a current is chosen so that the surface emitting laser operates within a bistability zone of the surface emitting laser, and wherein the method comprises detecting, by a photodetector, the laser pulses emitted by the surface emitting laser and generating random numbers from the detected laser pulses.
System and method for preventing thermal induced failures in vertical cavity surface emitting laser (VCSEL) array
The present invention discloses a VCSEL array that is divided into at least a first and a second area. The first area covers the center of the array and is surrounded by the second area. The first area would experience higher temperature than the second area after the VCSELs in both areas are turned on for a given time period. VCSELs in the first area are electrically connected to a first metal layer portion. VCSELs in the second area are electrically connected to a second metal layer portion. The first and second metal layer portions are electrically insulated from each other.
ELECTRONIC DEVICE MANUFACTURING METHOD, LASER DEVICE, AND WAVELENGTH SEQUENCE CALCULATION SYSTEM
An electronic device manufacturing method includes acquiring a pulse spectral shape of pulse laser light, and a target integrated spectral shape realized by the pulse laser light of pulses generated based on wavelength sequence in which a center wavelength of the pulse laser light periodically changes; calculating target center wavelengths allocated to the pulses to realize the target integrated spectral shape, and a number of allocation pulses of each target center wavelength being the number of allocation pulses per cycle of the wavelength sequence; calculating the wavelength sequence by correspondingly allocating at least one first center wavelength having the number of allocation pulses of 2 or greater so that the smaller the number of allocation pulses is, the larger a time interval of the allocation pulses for the first center wavelength is, and then correspondingly allocating at least one second center wavelength having the number of allocation pulses of 1.
Soldering system of semiconductor laser element
A soldering system that determines soldering quality of elements relative to a housing at the moment of soldering semiconductor laser elements. A soldering device that performs soldering of a semiconductor laser element to a semiconductor laser module, a robot that conveys the module, a camera, and a control device that controls the robot and camera based on imaging output of the camera. The robot conveys the module and changes the position and posture of the camera. The camera images the module. The control device calculates the position of the semiconductor laser element based on the imaging output, calculates parallelism between the housing of the module and the semiconductor laser element based on the change in light intensity related to the imaging output when changing the relative position between the camera and the subject, and determines the quality of soldering of the semiconductor laser element based on the position and parallelism.
System and Method for Phase Stabilization of Optical Sources
There is described a system and method for controlling the phase relationship between two optical signals and an optical frequency comb. Two optical mixers are configured to generate beat signals based on the optical signals and the optical frequency comb. A first detector is configured to measure the relative phase between the two beat signals, and a second detector is configured to measure the relative phase between one of the beat signals and a reference signal. One or more control signals based on the measurements are then used to control the phases of the optical signals to maintain a desired phase relationship between the optical signals and the optical frequency comb. The system and method can be configured such that the optical frequency comb is symmetric about a central frequency, and the phase relationship is resilient to noise induced by the generation of the optical frequency comb.