Mcnc

William Devereux Palmer

Dorota Temple

William Thomas Joines

Richard LaBennett

A flexible optoelectronic circuit is assembled on and released from a substrate, and therefore independent of a substrate. The substrate includes semiconductor substrates having a release layer. The release layer is etched to release the optoelectronic circuit such that the resulting circuit is flexible. Both optical elements, such as waveguides, and conductive elements are formed in layers, generally between insulating layers. The elements may be formed and patterned using standard semiconductor manufacturing techniques.

Flexible optoelectronic circuit and associated method

A passive microwave component with constant impedance and electrically adjustable phase length utilizes a microstrip or stripline transmission line geometry incorporating a composite dielectric having both ferroelectric (FE) and ferromagnetic (FM) properties. These properties can be varied with externally applied electric and magnetic fields such that the phase length (or electrical length) of the line can be varied without varying the characteristic impedance of the transmission line. Thus, the component can be electrically tuned without adversely affecting the impedance match. The component can be used in microwave devices such as phase shifters, frequency filters, directional couplers, power dividers and combiners, and impedance-matching networks.

Tunable microwave components utilizing ferroelectric and ferromagnetic composite dielectrics and methods for making same

A current regulator controls the electron emission from a cold cathode using closed-loop feedback from a current sensor in the cathode connection. The regulator circuit includes a cold cathode, a current-sensing element, a current-limiting element, and current-control element. Additionally, the closed-loop current regulator may comprise a reference element for generating the reference level, a circuit power supply and a cathode bias supply. The regulator and cathode may be assembled from separate components, or the entire circuit may be integrated onto a single substrate. In one embodiment, the current level is set by adjusting the reference element directly. In a second embodiment, the current level is set by adjusting the circuit power supply, so that the current level can be set remotely without the need to adjust the reference element directly. The second embodiment is preferably suited for the regulation of beam current in analytical instrumentation. In a third embodiment, the fixed reference element is replaced with a time-varying voltage signal. The current from the cathode then becomes a linear function of the time-varying reference signal. The third embodiment is preferably suited for application as an amplifying element or as the electron source in an emissive display.

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Durham, NC, United States of America

William Devereux Palmer