Abstract:
Apparatus and methods for altering one or more spectral, spatial, or temporal characteristics of a light-emitting device are disclosed. Generally, such apparatus may include a volume Bragg grating (VBG) element that receives input light generated by a light-emitting device, conditions one or more characteristics of the input light, and causes the light-emitting device to generate light having the one or more characteristics of the conditioned light.
Abstract:
High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.
Abstract:
High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.
Abstract:
A sensor for detecting material degradation may include an optical fiber and a housing through which the optical fiber extends. An end cap may be affixed to an end of the housing. Light provided through the optical fiber may be reflected off of the end cap back through the optical fiber. The end cap may be made of a material of interest, and may be situated in an environment wherein the material of interest is present. A light source may provide input light through the optical fiber. A portion of the input light may be reflected off of the end cap. A light receptor may receive the reflected light via the optical fiber. A processing unit may be adapted to compare a measured intensity of the reflected light to a threshold, and to initiate an alarm condition if the measured intensity is below the threshold.
Abstract:
A semiconductor laser diode system may include a single longitudinal mode laser diode and a feedback system that monitors and controls the emission characteristics of the laser diode. The laser diode may include a gain medium and an optical feedback device. The feedback system may include a wavelength discriminator, an optical detector, a microprocessor, and a laser controller. Such a semiconductor laser diode system may be used to produce laser light having coherence length, wavelength precision, and wavelength stability that is equivalent to that of a gas laser. Accordingly, such a semiconductor laser diode system may be used in place of a traditional gas laser.
Abstract:
Apparatus for performing Raman spectroscopy may include a first laser source having a first emission wavelength and a second laser source having a second emission wavelength. A separation between the first and second emission wavelengths may correspond to a width of a Raman band of a substance of interest. A switch may provide switching between the first and second laser sources. An ensemble of laser emitters may be provided. A Bragg grating element may receive laser light from the ensemble. An optical system may direct light from the Bragg grating element into an optical fiber. A combined beam through the optical fiber may contain light from each of the emitters.
Abstract:
Apparatus for performing Raman analysis may include a laser source module, a beam delivery and signal collection module, a spectrum analysis module, and a digital signal processing module. The laser source module delivers a laser beam to the beam delivery and signal collection module. The beam delivery and signal collection module delivers the laser source beam to a sample, collects Raman scattered light scattered from the sample, and delivers the collected Raman scattered light to the spectrum analysis module. The spectrum analysis module demultiplexes the Raman scattered light into discrete Raman bands of interest, detects the presence of signal energy in each of the Raman bands, and produces a digital signal that is representative of the signal energy present in each of the Raman bands. The digital signal processing module is adapted to perform a Raman analysis of the sample.
Abstract:
High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.
Abstract:
Apparatus for performing Raman spectroscopy may include a first laser source having a first emission wavelength and a second laser source having a second emission wavelength. A separation between the first and second emission wavelengths may correspond to a width of a Raman band of a substance of interest. A switch may provide switching between the first and second laser sources. An ensemble of laser emitters may be provided. A Bragg grating element may receive laser light from the ensemble. An optical system may direct light from the Bragg grating element into an optical fiber. A combined beam through the optical fiber may contain light from each of the emitters.
Abstract:
Fiber optic devices including volume Bragg grating (VBG) elements are disclosed. A fiber optic device may include one or more optical inputs, one or more VBG elements, and one or more optical receivers. Methods for manufacturing VBG elements and for controlling filter response are also disclosed. A VBG chip, and fiber optic devices using such a chip, are also provided. A VBG chip includes a monolithic glass structure onto which a plurality of VBGs have been recorded.