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: The improvement of the performance of holographic glasses with recorded holograms as measured by a figure of merit of the holographic glasses is disclosed. The improvement in the figure of merit of the holographic glasses is obtained at least in part with the addition of arsenic in the formation of the holographic glasses. The presence of arsenic increases the figure of merit as measured at a wavelength of interest of a holographic glass with a recorded hologram as compared to a holographic glass with a recorded hologram that does not contain arsenic.

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: The improvement of the performance of holographic glasses with recorded holograms as measured by a figure of merit of the holographic glasses is disclosed. The improvement in the figure of merit of the holographic glasses is obtained at least in part with the addition of arsenic in the formation of the holographic glasses. The presence of arsenic increases the figure of merit as measured at a wavelength of interest of a holographic glass with a recorded hologram as compared to a holographic glass with a recorded hologram that does not contain arsenic.

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: 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.

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: 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: The improvement of the performance of holographic glasses with recorded holograms as measured by a figure of merit of the holographic glasses is disclosed. The improvement in the figure of merit of the holographic glasses is obtained at least in part with the addition of arsenic in the formation of the holographic glasses. The presence of arsenic increases the figure of merit as measured at a wavelength of interest of a holographic glass with a recorded hologram as compared to a holographic glass with a recorded hologram that does not contain arsenic.

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: 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: 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: The improvement of the performance of holographic glasses with recorded holograms as measured by a figure of merit of the holographic glasses is disclosed. The improvement in the figure of merit of the holographic glasses is obtained at least in part with the addition of arsenic in the formation of the holographic glasses. The presence of arsenic increases the figure of merit as measured at a wavelength of interest of a holographic glass with a recorded hologram as compared to a holographic glass with a recorded hologram that does not contain arsenic.

Abstract: Tread cradles for covering a sole of an article of footwear having at least one cleat are described, the tread cradles comprising bases having first and second sides, treads disposed on the first side of the bases, and disposed on the second side of the base, means for reversibly securing the cleat to the base, thereby removably attaching the article of footwear to the tread cradle. Covering the sole prevents mud, grass, and other debris from sloughing off, protects the sole from abrasive surfaces, such as concrete and asphalt, protects flooring surfaces, and may cushion the article of footwear for greater user comfort.

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 individually addressable 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: 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: 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.

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 individually addressable 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: 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.