Patents


Oliver T. Strand, Robert J. Deri, and Michael D. Pocha
Microminiature Optical Waveguide and Method for Fabrication
U.S. Patent 5,846,694
December 8, 1998
A method for manufacturing low-cost, nearly circular cross-section optical waveguides. A thin layer of material that a molten waveguide material (polymer or doped silica) will wet is deposited on a substrate that the waveguide material cannot wet or coat and is patterned to describe the desired surface-contact path pedestals for a waveguide. A resist material is deposited and excess is removed to form pattern marks. The waveguide material is etched away to form waveguide precursors, and the masks are removed. Heat is applied to reflow the waveguide precursors into near-circular cross-section waveguides that sit on top of the pedestals. The waveguide material naturally forms nearly circular cross sections because of surface tension effects. After cooling, the waveguides maintain the round shape. If the width and length are the same, spherical ball lenses are formed. Alternatively, the pedestals can be patterned to taper along their lengths on the surface of the substrate, causing the waveguides to assume a conical taper after heat has caused them to reflow.

Richard F. Post
Passive Magnetic Bearing Element with Minimal Power Losses
U.S. Patent 5,847,480
December 8, 1998
Systems employing passive magnetic bearing elements having minimal power losses. These include stabilizing elements employing periodic magnet arrays and inductively loaded circuits that improve the elements disclosed in U.S. Patent No. 5,495,221, "Dynamically Stable Magnetic Suspension/Bearing System." The improvements increase the magnitude of the force derivative, while reducing the power dissipated during the normal operation of the bearing system to provide a passive bearing system that has virtually no losses under equilibrium conditions, that is, when the supported system is not subject to any accelerations except those of gravity.


Craig R. Wuest
Microgap Flat Panel Display
U.S. Patent 5,847,509
December 8, 1998
A microgap flat panel display that includes a thin gas-filled display tube that uses switched X-Y "pixel" strips to trigger electron avalanches and activate a phosphor at a given location on a display screen. The panel uses the principle of electron multiplication in a gas subjected to a high-voltage electric field to provide sufficient electron current to activate standard luminescent phosphors located on an anode. The X-Y conductive strips, which are a few micrometers wide, may be deposited on opposite sides of a thin insulating substrate or on one side of the adjacent substrates and function as a cathode. They are separated from the anode by a gap filled with a suitable gas. Electrical bias is selectively switched onto X and Y strips to activate a "pixel" in the region where these strips overlap. A small amount of a long-lived radioisotope is used to initiate an electron avalanche in the overlap region when bias is applied. The avalanche travels through the gas-filled gap and activates a luminescent phosphor of a selected color. The bias is adjusted to give a proportional electron multiplication to control brightness for a given pixel.


Lawrence M. Wagner and Michael J. Strum
Load Regulating Expansion Fixture
U.S. Patent 5,848,746
December 15, 1998
A free-standing, self-contained device for bonding ultrathin metallic (such as 0.001-inch beryllium) foils. The device will regulate to a predetermined load for solid-state bonding when heated to a bonding temperature. The device includes a load-regulating feature, whereby the expansion stresses generated for bonding are regulated and self-adjusting. The load regulator comprises a pair of friction isolators with a plurality of annealed copper members located between them. The device, with the load regulator, will adjust to and maintain a stress level needed to successfully and economically complete a leak-tight bond without damaging thin foils or other delicate components.



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