Abstract: A modulating retro-reflector (MRR) can be configured to provide a large field of view. The MRR can include a solid corner cube reflector (CCR) manufactured of a material having a high index of refraction at the desired operating wavelength. CCRs made from high index materials such as InP or Si, have an index of refraction of approximately 3.48 at an operating wavelength of approximately 1550 nm and can provide a conical Field of View (FOV) of greater than ±60 degrees compared to less than ±30 degrees for CCRs made from BK-7. Each CCR can include one or more elements configured to modulate an optical signal incident on the CCR. A retro-modulating transponder can use fewer large FOV MRRs to support communication over a predetermined incident optical span compared to narrower FOV MRRs resulting in lower cost, smaller size, weight and power requirements.

Abstract: A dynamic optical tag system and method that allows for operation over a wide temperature range. A variable wavelength optical source, such as a dual wavelength fiber laser, is generated by combining the outputs from two distributed feedback lasers having separate operating wavelengths using a wavelength division multiplexer (WDM). A quantum well optical modulator mounted on the front surface of a retro-reflector in the remote receiver end of the communication link is biased to modulate one of the two laser wavelengths. At higher temperatures, the optical modulator can be biased to operate at the wavelength of one of the two lasers. At a lower temperature, the optical modulator can be biased to operate at the second of the two wavelengths. The DC bias required to tune the optical modulator is reduced by operating at two separate wavelengths depending on temperature.

Abstract: A Polymer Dispersed Liquid Crystal (PDLC) capable of consistent performance over a wide temperature range. The PDLC includes electrodes connected to each of the resistive layers, such as ITO layers, of the PDLC. A FET switch couples each electrode to a corresponding capacitor. The capacitors are charged using a power source. The energy stored in the capacitors can be transferred to the resistive layers to heat the PDLC. A controller can pulse the FET switches to control the amount of energy transferred from the capacitors to the resistive layers.

Abstract: A pulsed fiber laser and associated electronics contained in a miniature package is disclosed. The Pulsed Fiber Laser Source (PFLS) can be a single-stage high gain master oscillator power amplifier (MOPA) type fiber laser source. The PFLS can include a distributed feedback (DFB) laser, a narrowband optical filter, a broad area high-power pump diode, and Erbium/Ytterbium (Er/Yb) double cladding doped fiber. Input electrical pulses drive the DFB laser diode to emit optical pulses that are then amplified by the optical amplifier. Active and passive cooling elements may be incorporated for continuous operation without rest time. Passive cooling for intermittent pulsed applications allows the laser source to be miniaturized by eliminating active cooling elements and associated power supplies and controllers. Low duty cycle relaxes drive requirements and further reduces the size.

Abstract: A fiber optic monitor that utilizes optical phase interferometry to monitor a patient's vital signs such as respiration, cardiac activity, blood pressure and body's physical movement. The monitor, which is non-invasive, comprises an optical fiber interferometer that includes an optical fiber proximately situated to the patient so that time varying acousto-mechanical signals from the patient are coupled into the optical fiber. Responsive thereto, the interferometer generates a time-varying optical intensity resulting from the interference of optical signals, which are detected at a photo-detector. A signal processor coupled to the optical detector provides one or more processed output signals indicative of the vital functions. The monitor system has broad applicability, from routine monitoring of infants at home to detection of apnea, arrhythmia, blood pressure and trauma.

Abstract: A laser small arms transmitter (SAT) includes a housing having a hollow interior and a clamp structure connected to the housing for rigidly securing the housing to a barrel of a weapon such as an M16A1 rifle. A spyglass shaped metal laser tube is rigidly mounted inside the housing. A lens is mounted in a forward segment of the laser tube and positioned in alignment with a bore in a forward side of the housing. A cylindrical laser diode can is mounted in a rearward segment of the laser tube. A circuit including a photo-optic sensor is mounted inside the housing and selectively energizes the laser diode to cause the same to emit a laser beam through the lens when a blank cartridge is fired. The rear segment of the laser tube is dimensioned and configured so that it can permanently bent to align the laser beam emitted by the laser diode with the barrel of the weapon.

Abstract: Soldiers and vehicles are fitted with infrared laser detectors for detecting simulated laser bullets and artillery shells from SAT-equipped small arms weapons and tanks employing laser scanner transmitters. An infrared LED is mounted inside the protective housing which supports each laser detector for illuminating the exterior surface of a window, lens or other transparent optical element positioned in front of the detector. Dirt, dust, mud, snow, shoe polish or other contaminant on the exterior surface of the optical element scatters the infrared radiation from the LED and in accordance with a test periodically performed by a test circuit, if the scattered signal exceeds a predetermined threshold value, a visual and/or audible warning is given to the player. If the optical element is not cleaned within a predetermined time after the warning, a kill command is executed to prevent the player from cheating.

Abstract: An all-optical precision gunnery simulation (PGS) system that may be adapted to simulate many tactical gunnery scenarios. The eye-safe system of this invention uses a 1550 nanometer optical infrared (IR) signal to permit increased range and field-of-view (FOV) and reduced scintillation over that of the 904 nanometer IR signals known in the art. Temporal and spatial diversity permit error-free operation over long ranges through dust and scintillation. The system performs all trajectory simulation and hit-miss assessment at the target, thereby permitting the shooter to “fire and forget” without holding station to monitor the target position. The simulation results may be reported to the shooter by passively modulating the retroreflection of an optical return window signal from the shooter. Alternatively, the target may compute shooter position from incoming optical pixel signal data for use in reporting by means of an active narrow-beam optical signal from the target back to the shooter.

Abstract: A system for precisely calibrating the misalignment of a weapon-mounted zeroed small arms transmitter (ZSAT) laser beam axis with the shooter line-of-sight (LOS) to a target in a weapon training system. When a blank cartridge is fired through a blank fire adapter (BFA) affixed to the weapon muzzle in a predetermined disposition, the dynamic muzzle displacement during the first milliseconds may be characterized as a two-dimensional shooter-independent “signature” representative of the BFA disposition, the blank cartridge and the weapon. The misalignment of the ZSAT laser beam axis with the shooter LOS is calibrated by transmitting a sequence of optical pixel signals during an early portion of the dynamic muzzle displacement interval to paint a target. A shooter LOS offset is deduced from the number of pixel signals illuminating the target and stored to compensate for any misalignment of the ZSAT laser beam axis with the shooter LOS during later use.

Abstract: A combat IFF system, for use in a combat exercise or on the battlefield, including a helmet-mounted passive IFF response unit and a weapon-mounted IFF interrogatory unit for each soldier. Infrared (IR) signals are employed for both challenge and response. The IR response signal is a very narrowly-targeted reflection of the relatively narrow IR transmit signal, thereby minimizing interception opportunities. The transmit and response signals are encoded in a transaction that cannot be compromised even when either or both signals are intercepted and decoded by the enemy. The combat IFF system includes biometric anti-spoofing features that prevent any use by an enemy in possession of captured units. Military radio-frequency (RF) spectrum is not required so there are no bandwidth limitations on simultaneous IFF transactions in the battlefield. A combat IFF transaction is completed in milliseconds.

Abstract: A fiber optic monitor that utilizes optical phase interferometry to monitor a patient's vital signs such as respiration, cardiac activity, blood pressure and body's physical movement. The monitor, which is non-invasive, comprises an optical fiber interferometer that includes an optical fiber proximately situated to the patient so that time varying acousto-mechanical signals from the patient are coupled into the optical fiber. Responsive thereto, the interferometer generates a time-varying optical intensity resulting from the interference of optical signals, which are detected at a photo-detector. A signal processor coupled to the optical detector provides one or more processed output signals indicative of the vital functions. The monitor system has broad applicability, from routine monitoring of infants at home to detection of apnea, arrhythmia, blood pressure and trauma. The system can be implemented in embodiments ranging from a low cost in-home monitor for infants to a high end product for in hospital use.

Abstract: Soldiers and vehicles are fitted with infrared laser detectors for detecting simulated laser bullets and artillery shells from SAT-equipped small arms weapons and tanks employing laser scanner transmitters. An infrared LED is mounted inside the protective housing which supports each laser detector for illuminating the exterior surface of a window, lens or other transparent optical element positioned in front of the detector. Dirt, dust, mud, snow, shoe polish or other contaminant on the exterior surface of the optical element scatters the infrared radiation from the LED and in accordance with a test periodically performed by a test circuit, if the scattered signal exceeds a predetermined threshold value, a visual and/or audible warning is given to the player. If the optical element is not cleaned within a predetermined time after the warning, a kill command is executed to prevent the player from cheating.

Abstract: A fiber optic monitor that utilizes optical phase interferometry to monitor a patient's vital signs such as respiration, cardiac activity and body's physical movement. The monitor, which is non-invasive, comprises an optical fiber interferometer that includes an optical fiber proximately situated to the patient so that acousto-mechanical signals from the patient are coupled into the optical fiber. Responsive thereto, the interferometer generates a time-varying serial train of fringes which is detected by a photo-detector. A signal processor coupled to the optical detector provides one or more processed output signals indicative of the vital functions. The monitor system has broad applicability, from routine monitoring of infants at home to apnea, arrhythmia and trauma situations.

Abstract: A laser small arms transmitter (SAT) includes a housing having a hollow interior and a clamp structure connected to the housing for rigidly securing the housing to a barrel of a weapon such as an M16A1 rifle. A spyglass shaped metal laser tube is rigidly mounted inside the housing. A lens is mounted in a forward segment of the laser tube and positioned in alignment with a bore in a forward side of the housing. A cylindrical laser diode can is mounted in a rearward segment of the laser tube. A circuit including a photo-optic sensor is mounted inside the housing and selectively energizes the laser diode to cause the same to emit a laser beam through the lens when a blank cartridge is fired. The rear segment of the laser tube is dimensioned and configured so that it can permanently bent to align the laser beam emitted by the laser diode with the barrel of the weapon.

Abstract: A laser small arms transmitter (SAT) includes a housing having a hollow interior and a clamp structure connected to the housing for rigidly securing the housing to a barrel of a weapon such as an M16A1 rifle. A spyglass shaped metal laser tube is rigidly mounted inside the housing. A lens is mounted in a forward segment of the laser tube and positioned in alignment with a bore in a forward side of the housing. A cylindrical laser diode can is mounted in a rearward segment of the laser tube. A circuit including a photo-optic sensor is mounted inside the housing and selectively energizes the laser diode to cause the same to emit a laser beam through the lens when a blank cartridge is fired. The rear segment of the laser tube is dimensioned and configured so that it can permanently bent to align the laser beam emitted by the laser diode with the barrel of the weapon.

Abstract: A turret mounted gun on a shooter tank with a laser scanner transmitter in its barrel emits a laser beam upon a trigger pull. The laser beam is directed toward a target tank based upon a shooter's ranging and tracking using a standard fire control computer to provide conventional ranging and tracking. The target tank is scanned with the laser beam to measure target azimuth and target elevation with respect to a boresight of the gun of shooter tank. Optical receivers mounted on the turret of the target tank detect the laser beam and a system control unit determines the trigger pull time, target azimuth and target super elevation. The system control unit also determines a range to the target tank by comparing a set of GPS coordinates of the two tanks.

Abstract: A structure and a method of manufacturing a reflective notch coupler for an optical fiber are disclosed. The coupler is formed in an optical fiber by a pair of angled surfaces extending from the cladding of the optical fiber and meeting in the fiber's core to form an indentation in the fiber. One surface is reflectively coated and couples light into and out of the core of the optical fiber.

Abstract: An accelerometer comprises a base and cover together defining a chamber which receives an inertial mass. The diaphragm carries the inertial mass and is bolted between the base and the cover. The inertial mass and the base have facing incorrugated surfaces with offset teeth in each of the corrugated surfaces. An optical fiber is clamped between the teeth and extends between the corrugated surfaces. The intensity of light passing through the fiber changes with movement of the inertial mass with respect to the base. The inertial mass moves through the resiliency of the diaphragm, when the base is subjected to accelerations, such as those caused by vibrations. A reference optical fiber may also extend through the chamber above the inertial mass. The same light is supplied to both fibers and the intensity of light from both fibers is subtracted to leave the variation in intensity due to bending of the sensing optical fiber.

Abstract: An accelerometer comprises a base and cover together defining a chamber which receives an inertial mass. A diaphragm carries the inertial mass and is bolted between the base and the cover. The inertial mass and the base have facing corrugated surfaces with offset teeth in each of the corrugated surfaces. An optical fiber is clamped between the teeth and extends between the corrugated surfaces. The intensity of light passing through the fiber changes with movement of the inertial mass with respect to the base. The inertial mass moves through the resiliency of the diaphragm, when the base is subjected to accelerations, such as those caused by vibrations. A reference optical fiber may also extend through the chamber above the inertial mass. The same light is supplied to both fibers and the intensity of light from both fibers is subtracted to leave the variation in intensity due to bending of the sensing optical fiber.

Abstract: The present invention is directed to a method and apparatus for forming shaped foamed-glass articles. Glass particles are introduced to a pressure vessel in the presence of water. A pressure is applied to the pressure vessel sufficient to permit entrapment of water during sintering and sufficient to prevent foaming at processing temperatures. The temperature of the glass is increased to cause the glass to sinter and entrap water. The temperature of the glass is then increased to its fining temperature (T.sub.F) for a sufficient time to fine the glass. The temperature of the glass is reduced to its pressure release temperature (T.sub.PR). The pressure on the glass containing water is then reduced such as by extrusion to cause controlled foaming of the glass to occur. The glass is then cooled preferably by annealing to form the shaped foamed-glass article, typically pipe insulation.