Abstract: A method for estimating optical power in an optical channel includes determining a tunable filter full-width, FWF, by measuring a response of the tunable filter to a known signal and mapping the response to frequency. A portion of an optical channel is coupled to an input of the tunable optical filter. A peak power response, PR, and a full width tunable filter response, FWR, to the optical channel are determined by measuring a response of the tunable filter to the optical channel and mapping the response to frequency. A signal power, PS, is then calculated from the peak power response, PR, and a ratio of the full width tunable filter response, FWR, to the tunable filter full-width, FWF.

Abstract: An interferometer includes an optical beam splitter that splits an input optical signal into a first optical signal propagating in a first optical path comprising free space and a second optical signal propagating in a second optical path comprising a dielectric medium. A differential delay delays the second optical signal relative to the first optical signal by a differential delay time that is proportional to at least one of a temperature and a refractive index of the dielectric medium. A temperature controller in thermal contact with the dielectric medium changes the temperature of the dielectric medium to control at least one of thermal expansion/contraction and a temperature dependent change in the refractive index of the dielectric medium, thereby changing the differential phase delay.

Abstract: A ball that provides normalized images of a ground-based target subject captured over the course of the arc of its airborne trajectory.

Abstract: A microchannel plate for detecting neutrons includes a hydrogen-rich polymer substrate that defines a plurality of channels extending from a top surface of the substrate to a bottom surface of the substrate, where neutrons interact with the plurality of channels to generate at least one secondary electron. A top electrode is positioned on the top surface of the substrate and a bottom electrode is positioned on the bottom surface of the substrate. A resistive layer is formed over an outer surface of the plurality of channels that provides ohmic conduction with a resistivity that is substantially constant. An emissive layer is formed over the resistive layer. Neutron interaction products interact with the plurality of channels defined by the substrate and the emissive films to generate secondary electrons that cascade within the plurality of channels to provide an amplified signal related to the detection of neutrons.

Abstract: A microchannel plate includes a substrate defining a plurality of channels extending from a top surface of the substrate to a bottom surface of the substrate. A resistive layer is formed over an outer surface of the plurality of channels that provides ohmic conduction with a predetermined resistivity that is substantially constant. An emissive layer is formed over the resistive layer. A top electrode is positioned on the top surface of the substrate. A bottom electrode positioned on the bottom surface of the substrate.

Abstract: An optical communications system includes an optical transmitter that generates a modulated optical signal at an output. The modulated optical signal propagates through an optical link where the dispersion of the optical link is imprinted onto an optical spectrum of the modulated optical signal. A demodulator receives the modulated optical signal and filters at least a portion of the optical spectrum with the imprinted dispersion of the optical link, thereby mitigating effects of dispersion in the modulated optical signal and generating a demodulated optical signal at an output. An optical detector generates an electrical data signal from the demodulated optical signal.

Abstract: A multi-band RF transceiver for transmitting communications data and radar signals includes a transmitter having a source of communications data and radar signals. A modulator combines the data and radar signals and then modulates the combined signal with a carrier signal generated by a synthesizer. A processor instructs the synthesizer to change the carrier frequency and the source to provide data and radar signals corresponding to the carrier frequency so that multiple bands are transmitted over a desired spectrum. A receiver includes a demodulator that demodulates the received signal and a synthesizer that generates a signal that tunes the demodulator to the desired carrier frequency. A processor instructs the synthesizer to change the carrier frequency so that the demodulator demodulates the multiple bands of data and the radar signals over the desired spectrum.

Abstract: An optical receiver includes an optical detector having an input that is positioned to detect an optical data signal. The optical detector generates a voltage at an output that is proportional to an optical intensity of the optical data signal. A differential amplifier includes a data input that is electrically connected to the output of the optical detector and a decision threshold voltage signal input. The differential amplifier generates a data signal at a data output and an inverse data signal at a data_bar output. A decision threshold voltage signal generator includes an output that is coupled to the decision threshold voltage signal input of the differential amplifier. The decision threshold voltage signal generator generates a decision threshold voltage signal having an amplitude that causes the differential amplifier to maintain a substantially constant differential voltage between the data signal and the inverse data signal generated.

Abstract: An image intensifying device includes a lens that is positioned at a light input that forms an image of a scene. The image intensifying device also includes an image intensifier tube that includes a photocathode that is positioned to receive the image formed by the lens. The photocathode generates photoelectrons in response to the light image of the scene. The image intensifier tube also includes a microchannel plate having an input surface comprising the photocathode. The microchannel plate receives the photoelectrons generated by the photocathode and generating secondary electrons. An electron detector receives the secondary electrons generated by the microchannel plate and generates an intensified image of the scene.

Abstract: Methods and apparatus for generating strongly-ionized plasmas are disclosed. A strongly-ionized plasma generator according to one embodiment includes a chamber for confining a feed gas. An anode and a cathode assembly are positioned inside the chamber. A pulsed power supply is electrically connected between the anode and the cathode assembly. The pulsed power supply generates a multi-stage voltage pulse that includes a low-power stage with a first peak voltage having a magnitude and a rise time that is sufficient to generate a weakly-ionized plasma from the feed gas. The multi-stage voltage pulse also includes a transient stage with a second peak voltage having a magnitude and a rise time that is sufficient to shift an electron energy distribution in the weakly-ionized plasma to higher energies that increase an ionization rate which results in a rapid increase in electron density and a formation of a strongly-ionized plasma.

Abstract: A method and apparatus for multiplexing ions in an MSn mass spectrometer is provided. Ion are filtered to produce a group of ions of interest, the group of ions below a space charge limit of the MSn mass spectrometer. At least a portion of the group of ions are fragmented to form a fragmented group of ions. At least a portion of the fragmented group are stored such that a plurality of portions of the fragmented group can be sequentially selected for mass spectrometry analysis. Each of the plurality of portions of the fragmented group are sequentially selected and re-fragmented prior to mass spectrometry analysis. Each of the plurality of portions of the fragmented group are analyzed, via mass spectrometry, once each of the plurality of portions of the fragmented group has been fragmented.

Abstract: A method of fabricating a microchannel plate includes defining a plurality of pores extending from a top surface of a substrate to a bottom surface of the substrate where the plurality of pores has a resistive material on an outer surface that forms a first emissive layer. A second emissive layer is formed over the first emissive layer. The second emissive layer is chosen to achieve at least one of an increase in secondary electron emission efficiency and a decrease in gain degradation as a function of time. A top electrode is formed on the top surface of the substrate and a bottom electrode is formed on the bottom surface of the substrate.

Abstract: Embodiments of the present invention provide composite bodies having a discontinuous graphite preform and at least one silicon-bearing metal alloy infiltrant. Embodiments of the present invention also provide methods for producing such composite bodies. The metal alloy is preferably comprised of aluminum, copper, or magnesium, or combinations thereof. Certain preferred embodiments provide at least one aluminum alloy having from about 5% silicon to about 30% silicon, more preferably from about 11% to about 13% silicon, as an alloying element. Certain presently preferred embodiments provide an aluminum-silicon eutectic composition having about 12.5% silicon. Embodiments of the invention provide composite materials be “tuned” to more closely match thermal expansion characteristics of a number of semiconductor or integrated circuit materials such as, but not limited to, silicon, alumina, aluminum nitride, gallium nitride, and gallium arsenide while also providing high thermal conductivity.

Abstract: In various aspects, the present teachings provide systems and methods for reducing chemical noise in a mass spectrometry instrument that use a neutral chemical reagent and one or more mass filters to reduce interfering chemical background ion signals that are generated by ionization sources of mass spectrometers. In various embodiments, the neutral chemical reagent belongs to the class of organic chemical species containing a disulfide functionality.

Abstract: An optical spectrum monitor includes a tunable optical detector that receives optical channel monitoring signals from an optical channel and receives a control signal that selects a frequency of an optical channel monitoring signal for detection. The tunable optical detector detects the optical channel monitoring signal selected by the control signal and generates an electrical signal related to a power of the detected optical channel monitoring signal. A processor analyzes a plurality of differences between selected optical channel monitoring frequencies and their corresponding ITU frequencies and then generates the control signal at the output that corrects for at least one of systematic band offset and systematic band tilt in the optical channel monitoring frequency.

Abstract: An image intensifying device includes a lens that is positioned at a light input that forms an image of a scene. The image intensifying device also includes an image intensifier tube that includes a photocathode that is positioned to receive the image formed by the lens. The photocathode generates photoelectrons in response to the light image of the scene. The image intensifier tube also includes a microchannel plate having an input surface comprising the photocathode. The microchannel plate receives the photoelectrons generated by the photocathode and generating secondary electrons. An electron detector receives the secondary electrons generated by the microchannel plate and generates an intensified image of the scene.

Abstract: A modulator includes an electro-optical substrate and a first and second waveguide formed of a doped semiconductor material positioned on a surface of an electro-optical substrate forming a slot therebetween. A doping level of the semiconductor material being chosen to make the first and second waveguide conductive. A dielectric material is positioned in the slot which increases confinement of both an optical field and an electrical field inside the slot. A refractive index of the semiconductor material and a refractive index of the dielectric material positioned in the slot being chosen to reduce the V?·L product of the modulator.

Abstract: A mass spectrometer includes a pulsed ion source that generates an ion beam comprising a plurality of ions. A first timed ion selector passes a first group of ions. A first ion mirror generates a reflected ion beam comprising the first group of ions that at least partially compensates for an initial kinetic energy distribution of the first group of ions. A second timed ion selector passes a second group of ions. A second ion mirror generates a reflected ion beam comprising the second group of ions that at least partially compensates for an initial kinetic energy distribution of the second group of ions. A timed ion deflector deflects the second group of ions to a detector assembly comprising at least two ion detectors which detects the deflected ion beam.

Abstract: An emergency lighting system includes a plurality of emergency lights and a plurality of emergency power systems. Each of the plurality of emergency power systems is electrically connected to a respective one of the plurality of emergency lights through a respective one of a plurality of power switches. The emergency lighting system also includes a plurality of processors. Each of the plurality of processors is electrically connected to a respective one of the plurality of emergency power systems and executes software that monitors a status of a respective one of the emergency power systems and controls a state of the plurality of power switches. The emergency lighting system also includes a plurality of radio transceivers. Each of the plurality of radio transceivers is electrically connected to a respective one of the plurality of processors and communicates with other radio transceivers in the plurality of radio transceivers that are in radio wave proximity.

Abstract: A strongly-ionized plasma generator includes a chamber for confining a feed gas. An anode is positioned inside the chamber. A cathode assembly is positioned adjacent to the anode inside the chamber. An output of a pulsed power supply is electrically connected between the anode and the cathode assembly. The pulsed power supply comprising solid state switches that are controlled by micropulses generated by drivers. At least one of a pulse width and a duty cycle of the micropulses is varied so that the power supply generates a multi-step voltage waveform at the output having a low-power stage including a peak voltage and a rise time that is sufficient to generate a plasma from the feed gas and a transient stage including a peak voltage and a rise time that is sufficient to generate a more strongly-ionized plasma.