Abstract: Imaging systems and methods are provided. In one embodiment, an image system is disclosed that comprises a Raman gain medium configured to receive an image from a target area and a tunable laser configured to pump light into the Raman gain medium over a plurality of first wavelengths to induce amplification of the image over a plurality of second wavelengths strokes shifted from the plurality of first wavelengths. The image system further comprises an image detector system that receives and processes the amplified image over the plurality of second wavelengths.

Abstract: A Raman waveguide amplifier includes a waveguide comprising a core of a Raman-active medium dimensioned and configured as a self-imaging multimode waveguide. At least one input signal is coupled into the core at a wavelength within a Raman gain spectrum of the Raman-active medium relative to at least one pump beam. The pump beam is coupled into the core so as to amplify the at least one input signal via stimulated Raman scattering to provide an output signal corresponding to an amplified replica of the at least one input signal.

Abstract: An image detection system includes a multimode fiber amplifier. The multimode fiber amplifier includes a core configured to receive an input image that includes a plurality of input beams spanning a range of incidence angles and to propagate at least some of the input beams as different ones of a plurality of transverse modes along the core. The multimode fiber amplifier provides an amplified image at an output facet thereof corresponding to the input image. A focal plane detector includes an array of detectors arranged to receive different portions of the amplified image.

Abstract: A method and apparatus are provided for detecting tremors induced in a subject that are indicative of stress, emotion, fatigue, deception or other similar psychological states. The apparatus includes a signal source for directly applying an excitation signal having a predefined amplitude and frequency to the subject so as to induce the tremor. The apparatus also includes a Doppler system for irradiating the subject with electromagnetic radiation and for detecting the electromagnetic radiation returning from the subject following modulation by the induced tremor. The Doppler system also analyzes the returning electromagnetic radiation to determine at least one of an amplitude of the induced tremor and a phase shift of the induced tremor relative to the excitation signal provided by the signal source. The amplitude and/or phase shift of the modulated electromagnetic radiation provide information regarding the stress, emotion, fatigue, deception or other similar psychological states of the subject.

Abstract: The laser diode arrays with removable linear laser diode bars and the methods of removing and replacing linear laser diode bars of the present invention provide easy and immediate removal of individual linear laser diode bars in laser diode arrays. The laser diode array is at least partially made of a plurality of removable linear laser diode bars and a plurality of spacers, such that each removable linear laser diode bar is disposed between a respective pair of spacers. A linear laser diode bar may be slideably removed from between the respective pair of spacers in the laser diode array without breaking any mechanical connection between the removable linear laser diode bar and the respective pair of spacers. A replacement linear laser diode bar may then be slideably inserted between the respective pair of spacers without forming a mechanical connection between the replacement linear laser diode bar and the spacers.

Abstract: An optical fiber having an elevated threshold for stimulated Brillouin scattering is provided. The optical fiber includes a core and a cladding surrounding the core with both the core and the cladding designed to guide optical waves through the core while anti-guiding acoustic waves. Moreover, the optical fiber includes other features to alter the mode profile of the acoustic waves and/or to further promote their lateral radiation. For example, the optical fiber can include an irregular coating to alter the mode profile of the acoustic waves. In another example, the optical fiber can include a quarter wave layer surrounding the cladding to promote the lateral radiation of the acoustic waves. In order to further alter the mode profile of the acoustic waves, the cladding can also have a lateral thickness that varies irregularly in a lengthwise direction.

Abstract: A method and apparatus are provided for detecting tremors induced in a subject that are indicative of stress, emotion, fatigue, deception or other similar psychological states. The apparatus includes a signal source for directly applying an excitation signal having a predefined amplitude and frequency to the subject so as to induce the tremor. The apparatus also includes a Doppler system for irradiating the subject with electromagnetic radiation and for detecting the electromagnetic radiation returning from the subject following modulation by the induced tremor. The Doppler system also analyzes the returning electromagnetic radiation to determine at least one of an amplitude of the induced tremor and a phase shift of the induced tremor relative to the excitation signal provided by the signal source. The amplitude and/or phase shift of the modulated electromagnetic radiation provide information regarding the stress, emotion, fatigue, deception or other similar psychological states of the subject.

Abstract: The laser diode arrays with removable linear laser diode bars and the methods of removing and replacing linear laser diode bars of the present invention provide easy and immediate removal of individual linear laser diode bars in laser diode arrays. The laser diode array is at least partially made of a plurality of removable linear laser diode bars and a plurality of spacers, such that each removable linear laser diode bar is disposed between a respective pair of spacers. A linear laser diode bar may be slideably removed from between the respective pair of spacers in the laser diode array without breaking any mechanical connection between the removable linear laser diode bar and the respective pair of spacers. A replacement linear laser diode bar may then be slideably inserted between the respective pair of spacers without forming a mechanical connection between the replacement linear laser diode bar and the spacers.

Abstract: An electron beam pumped semiconductor laser screen and an associated fabrication method are described which provide a display screen that has a relatively long operating lifetime, is less expensive to produce, and operates at lower electron voltages and near room temperature conditions. The laser screen includes a multi quantum well active gain region having quantum wells of GaInP and barrier layers of (AlxGa1−x)InP, thereby permitting operation in the visible, red spectrum. Moreover, the first layer epitaxially grown on the sacrificial substrate is an etch stop layer of (GaxAl1−x)yIn1−yP that acts as an etch stop during the subsequent etching of the sacrificial substrate and may also be used to adjust the cavity length to the correct resonance condition. The laser screen also includes an output mirror having alternating layers of two different compositions of GaxAl1−xAs that are epitaxially grown on the multi quantum well active gain region.

Abstract: The laser diode arrays with removable linear laser diode bars and the methods of removing and replacing linear laser diode bars of the present invention provide easy and immediate removal of individual linear laser diode bars in laser diode arrays. The laser diode array is at least partially made of a plurality of removable linear laser diode bars and a plurality of spacers, such that each removable linear laser diode bar is disposed between a respective pair of spacers. A linear laser diode bar may be slideably removed from between the respective pair of spacers in the laser diode array without breaking any mechanical connection between the removable linear laser diode bar and the respective pair of spacers. A replacement linear laser diode bar may then be slideably inserted between the respective pair of spacers without forming a mechanical connection between the replacement linear laser diode bar and the spacers.

Abstract: The laser diode arrays with removable linear laser diode bars and the methods of removing and replacing linear laser diode bars of the present invention provide easy and immediate removal of individual linear laser diode bars in laser diode arrays. The laser diode array is at least partially made of a plurality of removable linear laser diode bars and a plurality of spacers, such that each removable linear laser diode bar is disposed between a respective pair of spacers. A linear laser diode bar may be slideably removed from between the respective pair of spacers in the laser diode array without breaking any mechanical connection between the removable linear laser diode bar and the respective pair of spacers. A replacement linear laser diode bar may then be slideably inserted between the respective pair of spacers without forming a mechanical connection between the replacement linear laser diode bar and the spacers.

Abstract: An optical fiber having an elevated threshold for stimulated Brillouin scattering is provided. The optical fiber includes a core and a cladding surrounding the core with both the core and the cladding designed to guide optical waves through the core while anti-guiding acoustic waves. Moreover, the optical fiber includes other features to alter the mode profile of the acoustic waves and/or to further promote their lateral radiation. For example, the optical fiber can include an irregular coating to alter the mode profile of the acoustic waves. In another example, the optical fiber can include a quarter wave layer surrounding the cladding to promote the lateral radiation of the acoustic waves. In order to further alter the mode profile of the acoustic waves, the cladding can also have a lateral thickness that varies irregularly in a lengthwise direction.

Abstract: An electron beam pumped semiconductor laser screen and an associated fabrication method are described which provide a display screen that has a relatively long operating lifetime, is less expensive to produce, and operates at lower electron voltages and near room temperature conditions. The laser screen includes a multi quantum well active gain region having quantum wells of GaInP and barrier layers of (AlxGa1−x)Inp, thereby permitting operation in the visible, red spectrum. Moreover, the first layer epitaxially grown on the sacrificial substrate is an etch stop layer of (GaxAl1−x)yIn1−yP that acts as an etch stop during the subsequent etching of the sacrificial substrate and may also be used to adjust the cavity length to the correct resonance condition. The laser screen also includes an output mirror having alternating layers of two different compositions of GaxAl1−xAs that are epitaxially grown on the multi quantum well active gain region.

Abstract: An optical fiber having an elevated threshold for stimulated Brillouin scattering is provided. The optical fiber includes a core and a cladding surrounding the core with both the core and the cladding designed to guide optical waves through the core while anti-guiding acoustic waves. Moreover, the optical fiber includes other features to alter the mode profile of the acoustic waves and/or to further promote their lateral radiation. For example, the optical fiber can include an irregular coating to alter the mode profile of the acoustic waves. In another example, the optical fiber can include a quarter wave layer surrounding the cladding to promote the lateral radiation of the acoustic waves. In order to further alter the mode profile of the acoustic waves, the cladding can also have a lateral thickness that varies irregularly in a lengthwise direction.

Abstract: A fiber optic projection device is provided that includes red, green and blue fiber optic sources, each of which includes at least one fiber amplifier for emitting an amplified signal of a predetermined wavelength. To provide signals that are scalable to high power levels, each fiber optic source can include a master oscillator, a plurality of fiber amplifiers for amplifying the input signals provided by the master oscillator and a combiner for combining the amplified signals emitted by each of the fiber amplifiers. While the fiber amplifier of each fiber optic source can be a dual core fiber that is appropriately doped, the red fiber optic source can include fiber amplifiers that rely upon Raman gain to provide the desired amplification. The red fiber optic source therefore not only includes a master oscillator, but also includes a red subharmonic oscillator for generating signals having a Raman seed wavelength for amplification by the fiber amplifiers.

Abstract: An electron beam pumped semiconductor laser screen and an associated fabrication method are described which provide a display screen that has a relatively long operating lifetime, is less expensive to produce, and operates at lower electron voltages and near room temperature conditions. The laser screen includes a multi quantum well active gain region having quantum wells of GaInP and barrier layers of (AlxGa1-x)InP, thereby permitting operation in the visible, red spectrum. Moreover, the first layer epitaxially grown on the sacrificial substrate is an etch stop layer of (GaxAl1-x)yIn1-yP that acts as an etch stop during the subsequent etching of the sacrificial substrate and may also be used to adjust the cavity length to the correct resonance condition. The laser screen also includes an output mirror having alternating layers of two different compositions of GaxAl1-xAs that are epitaxially grown on the multi quantum well active gain region.

Abstract: An optical fiber having an elevated threshold for stimulated Brillouin scattering is provided. The optical fiber includes a core and a cladding surrounding the core with both the core and the cladding designed to guide optical waves through the core while anti-guiding acoustic waves. Moreover, the optical fiber includes other features to alter the mode profile of the acoustic waves and/or to further promote the lateral radiation of at least some of the acoustic waves. For example, the optical fiber can include an irregular coating surrounding the cladding that varies in a lengthwise direction in order to alter the mode profile of the acoustic waves. In addition to or instead of the irregular coating, the optical fiber can include a quarter wave layer surrounding the cladding to promote the lateral radiation of the acoustic waves away from the core and cladding.

Abstract: An optical modulator and an associated modulation method are provided that utilize an optical fiber as the active medium such that the resulting fiber modulator is relatively inexpensive, but maintains high performance standards. The fiber modulator includes a core and a cladding surrounding the core which collectively form a longitudinally extending optical fiber capable of supporting the propagation of optical signals. The fiber modulator also includes first and second regions within the cladding and extending longitudinally therealong for establishing an internal bias electrical field across the core. The first and second regions are disposed on opposite sides of the core and have positive and negative electrical charges, respectively. The fiber modulator further includes first and second electrodes disposed on the cladding proximate the first and second regions, respectively, and extending longitudinally therealong.

Abstract: An optical modulator and an associated modulation method are provided that utilize an optical fiber as the active medium such that the resulting fiber modulator is relatively inexpensive, but maintains high performance standards. The fiber modulator includes a core and a cladding surrounding the core which collectively form a longitudinally extending optical fiber capable of supporting the propagation of optical signals. The fiber modulator also includes first and second regions within the cladding and extending longitudinally therealong for establishing an internal bias electrical field across the core. The first and second regions are disposed on opposite sides of the core and have positive and negative electrical charges, respectively. The fiber modulator further includes first and second electrodes disposed on the cladding proximate the first and second regions, respectively, and extending longitudinally therealong.

Abstract: An electron beam pumped semiconductor laser screen and an associated fabrication method are described which provide a display screen that has a relatively long operating lifetime, is less expensive to produce, and operates at lower electron voltages and near room temperature conditions. The laser screen includes a multi quantum well active gain region having quantum wells of GaInP and barrier layers of (AlxGa1−x)InP, thereby permitting operation in the visible, red spectrum. Moreover, the first layer epitaxially grown on the sacrificial substrate is an etch stop layer of (GaxAl1−x)yIn1−yP that acts as an etch stop during the subsequent etching of the sacrificial substrate and may also be used to adjust the cavity length to the correct resonance condition. The laser screen also includes an output mirror having alternating layers of two different compositions of GaxAl1−xAs that are epitaxially grown on the multi quantum well active gain region.