Abstract: The present invention provides an optoelectronic device, a method of manufacturing thereof, and an optical communications system including the same. The optoelectronic device includes an optical substrate coupled to a submount and including an optical device, and a signal and a ground conductor coupled to the submount, wherein the signal and ground conductors have a direction of signal propagation associated therewith, and wherein related transitions of the signal and ground conductors between the submount and the optical substrate are separated along the direction by a predetermined distance.

Abstract: The present invention provides an optoelectronic device, a method of manufacturing thereof, and an optical communications system including the same. The optoelectronic device includes an optical substrate coupled to a submount and including an optical device, and a signal and a ground conductor coupled to the submount, wherein the signal and ground conductors have a direction of signal propagation associated therewith, and wherein related transitions of the signal and ground conductors between the submount and the optical substrate are separated along the direction by a predetermined distance.

Abstract: Flexible ground connectors are adapted to withstand temperature-induced stresses. The connectors may be formed of low thermal conductivity materials. The connectors may be used within a semiconductor package that also encloses a thermoelectric cooling device, a conductive submount, and a semiconductor light source. The submount may be grounded to the package wall by locating a pair of the flexible ground connectors across a gap to a ledge in the wall. The ground connectors may be formed of stainless steel, and they may be gold plated for improved electrical conductivity.

Abstract: An optical microwave package eliminates launching electrical modes into a microwave strip-line by forming a moat in a housing portion of the package to suppress microwave resonant energy. The moat can be filled with a conductive material to further suppress package resonances. Additionally, the bottom of a substrate positioned within the housing is isolated from any conductive metal to further suppress microwave resonant energy.

Abstract: A system and method for optimizing the output of a semiconductor die is described. A lid for a semiconductor package includes a radio frequency resonance dampening material which can be repatterned in real time to minimize resonance reflection within the package. The patterning may take the form of structures within the material or different sections of the material having differing resistivities to resonance reflection. Upon determing that acceptable resonance reflection has been achieved, the material is cured.

Abstract: Flexible ground connectors are adapted to withstand temperature-induced stresses. The connectors may be formed of low thermal conductivity materials. The connectors may be used within a semiconductor package that also encloses a thermoelectric cooling device, a conductive submount, and a semiconductor light source. The submount may be grounded to the package wall by locating a pair of the flexible ground connectors across a gap to a ledge in the wall. The ground connectors may be formed of stainless steel, and they may be gold plated for improved electrical conductivity.

Abstract: A composition comprising a finely-divided non-magnetic solid and a dispersant comprising a poly(C.sub.2-4 -alkyleneimine) carrying at least two mono- or poly-(carbonyl-C.sub.1-7 -alkyleneoxy) groups, a dispersion of the composition in an organic medium and a dispersant comprising a poly(C.sub.2-4 -alkyleneimine) carrying at least two carbonyl- C.sub.1-7 -alkyleneoxy groups.

Abstract: In a display device utilizing ferroelectric (e.g., chiral, smectic C material), a stabilizing electric field perpendicular to the cell surfaces forces the molecules to orient themselves in one of two states both of which are parallel to the cell surfaces. A particular state is selected by a switching electric field also oriented perpendicular to the cell surfaces. The stabilizing field has a half-cycle time shorter than the switching time of the ferroelectric material, whereas the switching field duration is longer than or equal to the switching time of the material. The invention enables the use of relatively thick (e.g., .gtoreq.2 .mu.m) ferroelectric cells.

Abstract: In a liquid crystal device one interior surface of the cell is coated with a polymer (e.g., a crystalline polymer such as PET) which, when rubbed, produces alignment of the liquid crystal molecules, and the opposite interior surface is coated with a material (e.g., an amorphous polymer, such as PMMA) which, even if rubbed, does not produce such alignment. Also described is a combination of an aligning polymer and a non-aligning, non-polymer (e.g., a silane surfactant or bare ITO). This technique is particularly useful in producing alignment of relatively thick, ferroelectric smectic liquid crystal cells.

Abstract: Liquid crystal devices having excellent speed are produced by utilizing an appropriate liquid crystal mixture. This mixture is prepared by selecting liquid crystal materials having opposite pitch and having specifically chosen spontaneous polarizations.

Abstract: Domain wall motion in a slab of ferroelectric material gives rise to an electrical signal which may correspond, e.g., to electrode width fluctuations or to a radiation pattern incident on a sensitive layer. A device may have numerous ferroelectric readout tracks, in which case the number of electrical leads can be minimized by a layout in which unidirectional movement of a planar ferroelectric domain wall not only serves to scan a track but also select a track from a large number of tracks. Such device operation is a feature of a device in which a ferroelectric slab is cut, e.g., in the manner of a comb or ladder. Resulting devices may be operated by judicious cycling of voltages at as few as two control electrodes, one defining an access track, and the other being common to the readout tracks.

Abstract: Digital devices such as, e.g., shift registers and logical gates are disclosed which are predicated on domain wall motion in a film of a ferroelectric material, such as, e.g., gadolinium molybdate or lead germanate. Disclosed devices comprise electrodes on both sides of the film of ferroelectric material and may further comprise a resistive layer whose presence facilitates domain wall motion past inter-electrode gaps. Electrodes or facing portions of electrodes define regions in the film and, in particular, an input region and an output region.To facilitate series connection of devices, electrodes are designed so as to cause energy gain during device operation. According to such design, surface area of an output region is larger than surface area of an input region. A current sensor is electrically connected to an electrode defining such output region.

Abstract: Analog readout devices are disclosed which utilize domain wall motion in a film of ferroelectric material to produce an electrical signal having a desired waveform. Disclosed devices comprise electrodes disposed on facing sides of the film, at least one electrode being patterned in correspondence with the desired waveform. Readout from devices may be direct or as the difference between two signals produced by domain wall motion. In the latter case, constant-width pairs of electrodes may be used in combination with a feedback circuit to ensure constant-velocity ferroelectric wall motion.