摘要:
The present invention pertains to electronically controlled optical switching and interconnection arrangements enabling generation and processing of optical pulses including rerouting, serializing, modulation, and other processing or transformation of such pulses.
摘要:
An integrated photodetector-amplifier is described which is planar and exhibits excellent circuit characteristics including low input capacitance, high speed, and high sensitivity. Also, certain self-alignment features and a planar technology made fabrication of the circuits simpler and easier than most such circuits.
摘要:
Threshold electric fields required to achieve high speed matrix addressing of selected cells in a bistable nematic liquid crystal storage display are reduced by employing a short duration, priming pulse signal in accordance with the principles of the invention. The short priming pulse signal applied to a selected cell modifies the binding energy for disclinations attached to sites of orientational discontinuity, thereby changing the threshold field required for electrical switching between bistable states. Threshold reduction also depends on the AC frequency and duration of a writing pulse signal applied to the selected cell subsequent to the priming pulse signal.
摘要:
In order to prevent drift between the two stable states in the bulk of the liquid crystal material, a specific cell isolation region formed from the same liquid crystal material is required. This cell isolation is provided in one embodiment by a uniformly tilted liquid crystal alignment. The surface of the substrates between which the liquid crystal material is disposed is treated to provide the uniform tilt in regions which surround the bistable volumes of liquid crystal material.
摘要:
Monolithic integrated vertical-cavity surface-emitting laser devices are disclosed including an edge-emitting semiconductor pump laser (PL), an optically-pumped vertical-cavity surface-emitting laser (VCSEL), and a means for deflecting and shaping the output beam of the pump laser to optically excite the VCSEL. The optically-pumped VCSEL structure may be adapted to include a resonant cavity with multiple fixed wavelengths, or a resonance cavity whose wavelength is continuously tunable. Wafer level manufacturing techniques are also disclosed.
摘要:
A method of fabricating a vertical cavity surface emitting laser comprising the steps of epitaxially growing a first DBR positioned on a substrate wherein the first DBR is epitaxially grown using MOCVD. The substrate is orientated in an off-axis crystallographic direction which increases the radiative efficiency. A first cladding layer is positioned on the first DBR and an active region is epitaxially grown on the first cladding layer wherein the active region is epitaxially grown using plasma assisted MBE. A second DBR is epitaxially grown on the second cladding layer wherein the second DBR is epitaxially grown using MOCVD. The active region is epitaxially grown using plasma assisted MBE to increase the mole fraction of nitrogen (N) incorporation. The DBR's are grown using MOCVD to improve the electrical performance.
摘要:
An electro-optical device includes a vertical cavity surface emitting laser, a heterojunction light emitting device and heterojunction phototransistor on a semiconductor substrate. Layers of the heterojunction phototransistor and the heterojunction light-emitting device are electrically and optically coupled so there is regenerative optical and electrical feedback between them. Layers of the heterojunction light-emitting devices are proton implanted to control the feedback. Plural such devices are electrically and optically coupled together to perform logic functions, such as EXCLUSIVE OR, in response to optical signals.
摘要:
A bistable nematic liquid crystal display cell is electrically switched between topologically equivalent, asymmetric horizontal states. The cell includes upper and lower parallel substrates, upper and lower topographically textured tilt alignment surfaces on the corresponding substrates, and nematic liquid crystal material between the substrates. In an active region of the cell, the tilt alignment surfaces form an unequal reverse tilt boundary condition. In an isolation region surrounding the active region of the cell, the tilt alignment surfaces are formed to avoid the reverse tilt boundary condition.
摘要:
A bistable nematic liquid crystal display cell is switched between topologically equivalent, asymmetric horizontal states. Switching is initiated by application of a directional, symmetry breaking field such as a transverse magnetic field. An electric potential is then applied across the cell to complete the switching cycle and maintain the state. The cell includes upper and lower parallel substrates, upper and lower topographically textured tilt alignment surfaces on the corresponding substrates, and nematic liquid crystal material between the substrates. In an active region of the cell, the tilt alignment surfaces form an equal reverse tilt boundary condition. In an isolation region surrounding the active region of the cell, the tilt alignment surfaces form a parallel tilt boundary condition.
摘要:
A row and column matrix of strip electrodes is utilized for switching bistable liquid crystal display cells from the vertical state to the horizontal state via resistive heating by applying an electric current of sufficient magnitude and duration to selected electrodes. Resistive heating causes the liquid crystal to undergo a phase transition from the nematic mesophase to an isotropic phase. Extinction of the current permits the liquid crystal to cool preferentially into the horizontal state of the nematic mesophase. Horizontal-to-vertical state switching is performed by conventional electric field effect techniques.