摘要:
A radiation sensor. The inventive sensor has a two-level detector structure formed on a substrate in which a thermal detector element is suspended over the substrate as a microbridge structure. A receiver of electromagnetic radiation is provided on the same side of the substrate in a manner that efficiently couples the radiation field to the thermal detector element. The thermal detector element has a sandwich structure including a heater metal layer, a dielectric layer, and a thin film thermo-resistive material. The thermal detector element is suspended out of physical contact with the receiver. In one embodiment, the receiver is an antenna having a crossed bowtie configuration that efficiently couples the radiation field to the detector element. The inventive radiation sensors are especially useful for mm-wave and microwave sensing applications. The sensor can be used individually or in linear or two-dimensional arrays thereof. The invention also is directed to a method of fabricating such a radiation sensor.
摘要:
A low profile receiving and/or transmitting antenna includes an array of lenses that focuses millimeter wave or other radiation onto a plurality of conventional patch antenna elements. The lenses and antenna elements are physically configured so that radiation at a tuning wavelength impinging on the antenna at a particular angle of incidence is collected by the lenses and focused onto the antenna elements in-phase. Two rotatable prisms may be disposed above the lenses to alter the angle of incidence of incoming or outgoing radiation to match the particular angle of incidence.
摘要:
Optical data processing systems are described for processing four NxN matrices A, B, C, D to calculate the expression CA.sup.-1 B+D. Multi-cell spatial light modulators are employed in conjunction with control circuits to perform matrix inversion, multiplication and addition.
摘要:
An electron beam addressed crystal light valve (LCLV) produces an AC voltage across a liquid crystal layer from a single polarity electron beam, and exhibits very high resolution. A mirror and a thin layer of partially conductive material are deposited on a support membrane on the electron beam side of the liquid crystal. The partially conductive layer is divided into a series of pixel elements by a conductive matrix which faces the electron beam. Electrons from the beam are absorbed by the partially conductive layer to establish a negative voltage across the liquid crystal, and then flow out to the conductive matrix to produce an AC voltage prior to the next electron beam scan. The conductive matrix is connected in circuit with a transparent electrode which provides a voltage reference on the readout side of the liquid crystal. The elements of the device are designed with electrical parameters that produce a discharge rate from the partially conductive layer fast enough to complete an AC cycle between successive electron beam scans, but slow enough for the liquid crystal to respond and produce an image.
摘要:
There is disclosed a single crystal silicon charge storage apparatus suitable for use in an alternating current driven liquid crystal light valve having therein a moderately doped microchannel stop grid. The charge storage medium is made of a high resistivity substrate on which an MOS capacitor is formed having fast photoelectric transient response and capable of operating over a wide frequency range. A doped microgrid structure is formed in one side of the substrate to prevent charge carrier spreading at the silicon-silicon dioxide interface and to provide a focusing electric field for the charge carriers. The signal from the substrate is electrically coupled through high-reflectivity mirrors and light blocking layers to the liquid crystal.
摘要:
A liquid crystal light valve which uses the transfer of charge carriers representing a plurality of signals from a CCD array to a liquid crystal light modulated display medium. The signal charge is extracted from the back side of the CCD by driving the CCD clock voltages to zero and allowing the charge to diffuse to the back side where it is collected in a charge depleted region formed by a reverse biased diode and injected into the interface layers of a liquid crystal display medium.
摘要:
There is disclosed a single crystal silicon charge storage apparatus suitable for use in an alternating current driven liquid crystal light valve. The charge storage medium is made of a high resistivity and photosensitive under AC excitation substrate on which an MOS capacitor is formed having fast photoelectric transient response and capable of operating over a wide frequency range. The AC activation provides to a liquid crystal light valve a greatly improved electrochemical stability. Electrically coupled high-reflectivity mirrors and light blocking layers can be used to couple the liquid crystal to the MOS capacitor.
摘要:
There is disclosed an anisotropically conductive interface comprising a plurality of cermet and dielectric layers for use in electro-optical devices to separate a substrate driver from an electro-optical display medium to prevent display light from affecting the driver. The substrate may be a photosensor, a charge coupled device or other matrix addressing circuitry arrangement. In general the substrate is one which can provide spatially modulated voltage and/or current patterns. The display medium may be a liquid crystal, an electro-chromic, an electro-luminescent material or the like. The interface provides direct current conductivity through the interface, insulative maintenance of the spatial modulation of the signal across the interface, light reflectivity, and high attenuation of transmitted light.
摘要:
There is disclosed a high performance coherent optical data processing system using a reflective mode liquid crystal light valve which is particularly suited for application to real-time coherent optical data processing. A preferred example of the system uses a reflective light valve comprising a CdS photoconductor, a CdTe light absorbing layer, a dielectric mirror, and a liquid crystal layer sandwiched between indium-tin-oxide transparent electrodes deposited on optical quality glass flats. The non-coherent light image is directed onto the photoconductor; this reduces the impedance of the photoconductor, thereby switching the AC voltage that is impressed across the electrodes onto the liquid crystal to activate the device. The liquid crystal is operated in a hybrid field effect mode. It utilizes the twisted nematic effect to create a dark off-state (voltage off the liquid crystal) and the optical birefringence effect to create the bright on-state. The liquid crystal thus modulates the polarization of the coherent read-out or projection light responsively to the non-coherent image. An analyzer is used to create an intensity modulated output beam which is projected through a Fourier transform lens onto a screen or other detector means.
摘要:
A method and apparatus for protecting a bolometer antenna imaging array from out of band electromagnetic energy is disclosed. Protective pads are disposed upon a window in an optical system forming a millimeter wave image on an array of bolometer antenna sensors. The protective pads are effectively opaque to infrared and visible emissions and are aligned to shade the bolometer portion of the bolometer antennas from infrared and visible emissions, while leaving the antenna portion of each sensor in the array exposed to intercept the millimeter wave energy incident upon them.