Abstract:
There is disclosed a high light level cutoff apparatus for use with night vision devices. The apparatus employs a digital method of timing implemented by a divider counter responsive to a crystal controlled input frequency which essentially controls a latch to produce an automatic shutoff of a night vision device during high light ambient conditions which conditions would undesirably reduce the effective life of such a night vision device. The circuitry disclosed utilizes a digital method of clocking and employs the latching relay as indicated which is operated by the digital counter. The circuitry provides a feed back from the latching relay which resets the night vision system so that it will re-operate if a transient accidentally serves to operate the goggles while the light level is in a high state. The circuitry provides a precise timing level via the counter which can be selected to provide extended time out periods from milliseconds to at least several minutes, circumventing many of the disadvantages of prior art devices.
Abstract:
A liquid crystal beam splitter includes a magnetic coil adapted to controllably orient, or tilt, the molecules of a layer of liquid crystal material and thereby detune the internal reflections of a polarized light beam component passing therethrough.
Abstract:
A radar system with auxiliary scanning provision for providing more dwell time on target, the system having a main frequency scan antenna with electronic or mechanical arrangements for auxiliary scanning. In the electronic embodiment, a space fed phased-array auxiliary antenna is provided, the radiating elements being interconnected with diode phase shifters, which are electronically actuated and synchronized to the antenna rotation. In the mechanical embodiment, a multi-sided prism arrangement in front of the antenna rotates in synchronism in a counter direction to the antenna, with auxiliary scanning data electronically manipulated for processing.
Abstract:
A liquid crystal wave division device includes first and second polarization changing cells, the polarization changing cells utilize homogeneously aligned nematic liquid crystal material to effect the change of polarization of a preselected frequency portion of a multifrequency incident light beam.
Abstract:
An apparatus for automatic speech recognition includes a plurality of processors, including template processors in which there are stored templates representative of both speech and non-speech sounds. Incoming sounds are continuously converted into digital signals in respective frames representative of speech and non-speech sounds, respectively. Sequences of such frames are compared with both the speech and non-speech templates to determine the closest matches. Endpoints of respective speech utterances are determined in response to the detection of respective non-speech-speech-non-speech sequences, whereupon such speech utterances are processed to recognize the same.
Abstract:
A self-aligned gate structure for a compound semiconductor MESFET is formedrom a lower silicon layer and an upper metal, e.g. nickel, region. The nickel region forms an etch mask for the silicon and subsequently an implantation mask for the drain and source regions. Etching of the silicon provides an undercut whereby the gate separation from the drain and source is defined. Heating the structure to anneal the implant diffuses the metal into the silicon to form a compound silicide gate structure.
Abstract:
A passive radar ranging system having an antenna system for receiving radiated electromagnetic energy emanating from an emitter source, plus a translation resolution system and a digital computation system for making phase measurements of the received electromagnetic energy with the translated and resolved energy signals being operated upon by a plurality of system spacing parameters, the radiated energy being modulated in a particular pattern, randomly modulated or unmodulated and with the emitter source being fixed or moving while the phase measurements are made from a single measurement platform which may also be fixed or moving with respect to the emitter source, the phase measurements being employed for determining the instantaneous range from the emitter source to the measurement platform.
Abstract:
A method of making a field-effect transistor includes performing a first ion implant in at least one region of a gallium arsenide substrate and forming a metallization layer of titanium-tungsten nitride on the implanted substrate. A metallic gold masking layer is deposited on the metallization layer over the implanted region and that portion of the metallization layer which is unmasked is removed. A self-aligned source of implantation ions is beamed into the first implanted region in those areas not covered by the masking layer. The substrate is then annealed to activate the implanted region with the gold masking layer remaining to greatly reduce the resistance of the gate electrode of said field-effect transistor.
Abstract:
A header for a wafer scale assembly includes a plurality of pins having end portions connectable to the wafer scale assembly. The end portions lie in a single plane that it substantially parallel to the plane of the wafer scale assembly.
Abstract:
A VSWR protection circuit employs first and second mixers whereby the first mixer receives at one input the transmitted frequency and has a local oscillator coupled to the other input to provide at its output a difference frequency. This difference frequency is applied to the input of the second mixer which also receives at another input a frequency which is the sum of an undesired EMI signal plus a residue signal due to reflection from the transmitter. The second mixer produces difference frequencies according to the output from the first mixer. The output from the second mixer is applied to a narrow bandpass filter which essentially allows the transmitted frequency to propagate. The output from the narrow band filter is then detected whereby a DC control voltage is provided and used as a gain control for the transmitting amplifier and essentially is independent of most interfering frequencies.