Abstract: Taggants can be incorporated into or onto value documents. The taggants comprise a crystalline taggant doped with two rare earth ions. The substrate or printed matter into which the taggant can be incorporated has a minimal absorption infrared wavelength window and the taggant is excited by incident infrared radiation in this wavelength range. Suitable first rare earth ions function as efficient broad band absorbers of incident infrared radiation and passes energy non-radiatively to a second rare earth ion, which emits infrared radiation at a wavelength greater than the incident infrared radiation. The emitted infrared radiation is also in the minimal absorption transmission window of the printed matter or the substrate into which the taggant is incorporated. Methods of authenticating the value document include detection of the emitted radiation at pre-determined values.

Abstract: Systems for preparation of a mark and authentication of a mark vis-a-vis a counterfeit mark. Emission spectra comprising intensity versus wavelength distributions are collected from a series of taggants. One or more taggants is selected from the collected emission data such that the spectra of the selected taggants are distinguishable. The selection is also based on a consideration of the emitted radiation of a substrate and a dispersive medium. The authentication system uses multivariate statistical analysis to calculate at least one measurement statistic of a mark to be authenticated and at least one statistical limit based on a series of training marks prepared by the preparation system. Authenticity of the mark is determined based on a comparison of the measurement statistic and the statistical limit.

Abstract: Cascading phosphors are described herein that produce emissions when they are excited by incident radiation. The cascading phosphors can be applied to articles, and can be useful in authenticating the article. The cascading phosphors include a host and at least three active ions.

Abstract: Systems for preparation of a mark and authentication of a mark vis-a-vis a counterfeit mark. Emission spectra comprising intensity versus wavelength distributions are collected from a series of taggants. One or more taggants is selected from the collected emission data such that the spectra of the selected taggants are distinguishable. The selection is also based on a consideration of the emitted radiation of a substrate and a dispersive medium. The authentication system uses multivariate statistical analysis to calculate at least one measurement statistic of a mark to be authenticated and at least one statistical limit based on a series of training marks prepared by the preparation system. Authenticity of the mark is determined based on a comparison of the measurement statistic and the statistical limit.

Abstract: A mount for suspending a laser medium has a cross section profile. The mount is configured to conduct heat away from the laser medium without imparting undue stress. The mount includes a laser host medium having a first cross section profile. A heat sink defines a bore. The bore has a second cross section profile configured to envelop the first cross section profile and further defines a generally uniform interspace between the first cross section profile and second first cross section profile. An amalgam of a mercury soluble metal is formed to substantially fill the interspace to support the laser host medium.

Abstract: An optical sensor system and method for determining the position, displacement and/or angle of a member (for example, a seal plate or valve gate) within a system (for example, a valve assembly in an aircraft turbine engine system or environmental control system). The system has, in one embodiment, a controller in communication with an encoder via a fiber optic line or similar light transmitter and the encoder further has an optically layered element. The optically layered element has at least one coating whose optical characteristics vary over the angles (or distance) of interest to provide feedback based on the position displacement and/or angle of the valve member. The system may communicate and/or be controlled by a computing system via a data communication network.

Abstract: An optical sensor system and method for determining the position, displacement and/or angle of a member (for example, a seal plate or valve gate) within a system (for example, a valve assembly in an aircraft turbine engine system or environmental control system). The system has, in one embodiment, a controller in communication with an encoder via a fiber optic line or similar light transmitter and the encoder further has an optically layered element. The optically layered element has at least one coating whose optical characteristics vary over the angles (or distance) of interest to provide feedback based on the position displacement and/or angle of the valve member. The system may communicate and/or be controlled by a computing system via a data communication network.

Abstract: An ignition system for igniting fuel in a gas turbine or diesel engine is described. The system includes a magnetic core-coil assembly having a magnetic core comprising at least one tape wound toroid of ferromagnetic amorphous metal alloy, a primary winding and a secondary winding. Also included are driver electronics for applying voltage to a spark plug to cause a spark to ignite the fuel. The core-coil assembly and driver electronics are capable of operating with a rapid charge and discharge cycle to produce a high spark pulse rate. In another aspect, a magnetic core-coil assembly is disclosed which has a magnetic core comprising at least one tape wound toroid of ferromagnetic amorphous metal alloy having a permeability ranging from about 250 to 500, a primary winding for low voltage excitation and a secondary winding for high voltage output.

Abstract: An ignition system for igniting fuel in a gas turbine or diesel engine is described. The system includes a magnetic core-coil assembly having a magnetic core comprising at least one tape wound toroid of ferromagnetic amorphous metal alloy, a primary winding and a secondary winding. Also included are driver electronics for applying voltage to a spark plug to cause a spark to ignite the fuel. The core-coil assembly and driver electronics are capable of operating with a rapid charge and discharge cycle to produce a high spark pulse rate. In another aspect, a magnetic core-coil assembly is disclosed which has a magnetic core comprising at least one tape wound toroid of ferromagnetic amorphous metal alloy having a permeability ranging from about 250 to 500, a primary winding for low voltage excitation and a secondary winding for high voltage output.

Abstract: An ignition system for igniting fuel in a gas turbine or diesel engine is described. The system includes a magnetic core-coil assembly having a magnetic core comprising at least one tape wound toroid of ferromagnetic amorphous metal alloy, a primary winding and a secondary winding. Also included are driver electronics for applying voltage to a spark plug to cause a spark to ignite the fuel. The core-coil assembly and driver electronics are capable of operating with a rapid charge and discharge cycle to produce a high spark pulse rate. In another aspect, a magnetic core-coil assembly is disclosed which has a magnetic core comprising at least one tape wound toroid of ferromagnetic amorphous metal alloy having a permeability ranging from about 250 to 500, a primary winding for low voltage excitation and a secondary winding for high voltage output.

Abstract: A spark ignition system for igniting fuel in an internal combustion engine is described. The spark ignition system includes a magnetic core-coil assembly having a ferromagnetic amorphous metal magnetic core and driver electronics. The core-coil assembly and driver electronics are capable of operating with a rapid charge and discharge cycle to produce a high spark pulse rate.

Abstract: A magnetic core-coil assembly generates an ignition event in a spark ignition internal combustion system having at least one combustion chamber. The assembly comprises a magnetic core of amorphous metal having a primary coil for low voltage excitation and a secondary coil for a high voltage output to be fed to a spark plug. A high voltage is generated in the secondary coil within a short period of time following excitation thereof. The assembly senses spark ignition conditions in the combustion chamber to control the ignition event. The assembly is constructed from sub-assembly parts that can be manufactured with existing machines at reasonable cost. The assembly is then potted in a housing consisting of a high temperature polymer.

Abstract: A magnetic core-coil assembly generates an ignition event in a spark ignition internal combustion system having at least one combustion chamber. The assembly comprises a magnetic core of amorphous metal having a primary coil for low voltage excitation and a secondary coil for a high voltage output to be fed to a spark plug. A high voltage is generated in the secondary coil within a short period of time following excitation thereof. The assembly senses spark ignition conditions in the combustion chamber to control the ignition event. The assembly is constructed from sub-assembly parts that can be manufactured with existing machines at reasonable cost.

Abstract: A magnetic core-coil assembly generates an ignition event in a spark ignition internal combustion system having at least one combustion chamber. The assembly comprises a magnetic core of amorphous metal having a primary coil for low voltage excitation and a secondary coil for a high voltage output to be fed to a spark plug. A high voltage is generated in the secondary coil within a short period of time following excitation thereof. The assembly senses spark ignition conditions in the combustion chamber to control the ignition event. The assembly is constructed from sub-assembly parts that can be manufactured with existing machines at reasonable cost.

Abstract: A birefringent bias is provided to an optical sensor by the addition of one or more single birefringent elements where the total birefringence-length product remains within the accepted tolerances of current devices. The bias provided by two or more elements is such that where each element has a birefringence, a dB/dT and a coefficient of thermal expansion term, the elements are arranged in tandem so that the combined birefringence terms equal the required birefringence bias and the dB/dT and coefficient of thermal expansion terms effectively cancel.

Abstract: A cladded birefringent pressure sensor for use in a pressure-sensing system. The sensor is a single composite plate consisting of two plates each with different indices of refraction. One surface of the sensor is exposed to the environmental pressure under measurement. A collimated broad band light source is transmitted via a fiber optic cable, a polarizer and a birefringent bias element which transmits a wavelength/polarization component of light through the sensor. An external force applied to the sensor adds a stress-induced component to the polarized lightwave. The lightwave exits the sensor and is captured by a second polarizer producing a modulated light spectrum. A focusing element collects the light and transmits it down another fiber optic cable. The cable transmits the light to an opto-electronic interface where the fringe pattern is extracted and a computer compatible signal is generated for a CPU.

Abstract: An integrated optical temperature and pressure sensor system that is birefringently biased. A broad band light source is transmitted via a fiber optic cable having a splitter, a collimator and a polarizer to a first birefringent bias element. The first birefringent element has a partially reflective coating to reflect back a portion of the light signal to the first polarizer to yield a first reflective modulated light that consists of temperature information irrespective of external forces. The non-reflected light continues to a second birefringent bias element. The second birefringent crystal provides additional birefringent bias to the light wave before the light wave enters an isotropic pressure sensor media. An external pressure applied to the sensor causes the light to experience stress-induced birefringence. The sensor comprises a highly reflective surface which redirects the light back through the sensor, both bias crystals and the polarizer to yield a second reflective modulated light spectrum.

Abstract: An optical diffuser plate disposed between a flashlamp and a solide state laser within a solid state laser pump chamber. The optical diffuser plate acts as a homogenizer of the pump light to reduce pumping inhomogeneities inherent with specular reflectors, while at the same time providing an efficient energy transfer from the flashlamp to the solid state laser. The optical diffuser plate can also filter out pump light below critical wavelengths that can be detrimental to the solid state laser.

Abstract: An active imaging system for viewing targets with a high degree of range resolution of approximately one foot. The imaging system utilizes a laser pulse which passes through an electro-optical pulse slicer which creates a sharp leading edge and/or a sharp falling edge on the laser pulse. The laser pulse travels to the target under observation, illuminates and reflects off of the target and returns to a camera. A target is viewed only during the time all or a portion of the returning laser pulse overlaps the time the camera shutter gate is open. The imaging system is particularly suited for determining depth information about a target by varying the time relationship when the returning laser pulse is received by the camera.

Abstract: An active night vision system capable of viewing a target over long distances utilizes laser illumination in eye-safe, invisible wavelength regions of about 1.52-1.76 .mu.m or about 2.03 .mu.m-2.34 .mu.m for illuminating a target; and electronically receives, intensifies and displays or stores the reflected image.