Abstract: A variable focal length lens integrated onto a silicon wafer. A light transmitting material such as gas or liquid is entrapped in a cavity in the wafer. The cavity has a flexible, light transmitting wall. The wall provides one surface of the lens. When the material inside the cavity is heated or cooled, the wall flexes and the focal length of the lens changes. The lens is suitable for use in temperature and pressure sensors, fiber optic communication networks, optical computers, and other applications.

Abstract: A method of fabricating a waveguide is described minimizing to a desired degree the effect of minor variations caused, for example, during manufacture from an ideal dimension to obtain a coupling of energy between two different frequencies of optical radiation propagated in the waveguide.

Abstract: A high power injection-locked laser system (10) is disclosed which includes master and slave lasers (12, 14) both of which are solid state lasers having continuous wave outputs. The slave laser has an output power at least ten times greater than the master laser. In the preferred embodiment, the slave laser is at least one-hundred times as powerful as the master laser. In accordance with the subject invention, a servo-loop control system is used to maintain the injection locked condition. A discriminant signal is generated that is indicative of drift in the slave laser cavity. The discriminant signal is used adjust the length of the slave laser cavity to maintain the locked condition.

Abstract: There is disclosed herein an integrated scanning tunneling microscope and an integrated piezoelectric transducer and methods for making both. The device consists of one or two arm piezoelectric bimorph cantilevers formed by micromachining using standard integrated circuit processing steps. These cantilevers are attached to the substrate at one area and are free to move under the influence of piezoelectric forces which are caused by the application of appropriate voltages generated by control circuitry and applied to pairs of electrodes formed as an integral part of the bimorph cantilever structure. The electric fields caused by the control voltages cause the piezoelectric bimorphs to move in any desired fashion within ranges determined by the design. The bimorph cantilevers have tips with very sharp points formed thereon which are moved by the action of the control circuit and the piezoelectric bimorphs so to stay within a very small distance of a conducting surface.

Abstract: This invention relates to an improvement in nucleic acid hybridization technology. Nucleic acids bind to complementary partners in a predictable manner such that the detection of complementary partners is possible. The acceleration of the binding process is desired objective and will find broad application in a variety of industrial, medical, and research uses. In particular this invention relates to the acceleration of nucleic acid hybridization by heterogeneous nuclear ribonucleoproteins [hnRNPs].

Abstract: There is disclosed herein a non linear transmission line comprised of a 50 ohm coplanar monolithic waveguide formed on top of a gallium arsenide substrate having a layer of lightly doped epitaxial gallium arsenide with a heavily doped buried layer, said epitaxial layer having spaced, electrically isolated islands. A self aligned Schottky diode junction is formed at the intersection of each isolation island with the center conductor of the transmission line. The second conductor of the transmission line is coupled through a contact window and an ohmic contact to the buried layer in each isolation island.

Abstract: Method and apparatus for measuring physical parameters, such as mass, and spring and damping constants, of a bone region of a human subject. The bone region is excited by a vibratory probe in a frequency range between about 70-1,600 Hertz, and the mechanical response of the tissue to the vibratory excitation is measured and converted to frequency-dependent force/displacement data. By correlating the force/displacement values determined from the force/displacement data with the behavior of a linear mechanical system having coupled bone and skin mass, the physical parameters which are contained in the equation of motion can be calculated.

Abstract: A system for characterizing objects to be sorted in real time and making sorting decisions using lasers to excite fluorescing dyes used to tag objects such as cells which flow through the laser beam in a stream of conductive fluid. The scattered light and fluorescent light at various frequencies define a multidimensional space. These light characteristics are sensed and digitized. The data so gathered is buffered and then compared to a binary classification tree. The individual parameters cause a certain path through the binary decision tree to be taken while the cell is passing from the point in the stream where the light characteristics are gathered to a point where electrostatically charged electrodes deflect individual statically charged drops containing cells to be sorted into various sorting bins. When the decision tree has been traversed, the sorting decision for the drop containing the cell which had those parameters is done.

Abstract: A millimeter-wave active probe for use in injecting signals with frequencies above 50GHz to millimeter-wave and ultrafast devices and integrated circuits including a substrate upon which a frequency multiplier consisting of filter sections and impedance matching sections are fabricated in uniplanar transmission line format. A coaxial input and uniplanar 50 ohm transmission line couple an approximately 20 GHz input signal to a low pass filter which rolls off at approximately 25 GHz. An input impedance matching section couples the energy from the low pass filter to a pair of matched, antiparallel beam lead diodes. These diodes generate odd-numberd harmonics which are coupled out of the diodes by an output impedance matching network and bandpass filter which suppresses the fundamental and third harmonics and selects the fifth harmonic for presentation at an output.

Abstract: A method of making an integrated, microminiature, electric-to-fluidic valve. The method comprises, in one embodiment, anisotropically etching a cavity in a silicon wafer to form a thin membrane at the bottom of a trench. Then a second wafer is etched to form an exit path surrounded by a valve seat positioned such that when these two wafers are sandwiched together, the valve seat lies under the membrane. An input passageway joining a manifold cavity formed around the valve seat is then etched in the surface of the second wafer which will mate with the diaphragm side of the first wafer. The two wafers are then bonded together after suitable alignment. A third pyrex wafer is then coated with a resistor material which will be over the cavity in the first wafer when the first and third wafers are bonded together. Conductive leads and wire attach pads are also formed. Finally, a fill hole is etched into the third wafer over the position of the cavity such that the cavity can be filled.

Abstract: A pressure regulator integrated in a sandwich of pyrex and silicon wafers. A first integrated valve comprising a silicon wafer in which there is etched a cavity so as to leave a flexible membrane of silicon is sandwiched between two other wafers which are usually pyrex. One of the pyrex wafers has a resistor pattern etched thereon in a location such that the resistor pattern is enclosed by the walls of the cavity when the pyrex wafer is bonded to the silicon wafer. The other pyrex wafer has a valve seat etched adjacent to the membrane in the silicon wafer. The cavity is filled with a fluid which, when heated, raises the vapor pressure in the cavity so as to cause the membrane to flex and change the spacing between the membrane and the valve seat thereby regulating flow. A second integrated valve has the same structure. One of these valves is coupled to a high pressure source and the other is coupled to a low pressure sink.

Abstract: Integral sharp tips on thin film cantilevers are produced by forming a rectangular silicon post on a (100) silicon wafer. Etching the top of the post leaves sharp silicon tips at the corners of what remains of the silicon post. A silicon dioxide cantilever with an integral tip is thermally grown over the silicon wafer and the sharp silicon tips.

Abstract: An integrated scanning tunneling microscope and an integrated piezoelectric transducer and methods for making both. The device consists of one or two arm piezoelectric bimorph cantilevers formed by micromachining using standard integrated circuit processing steps. These cantilevers are attached to the substrate at one area and are free to move under the influence of piezoelectric forces which are caused by the application of appropriate voltages generated by control circuitry and applied to pairs of electrodes formed as an integral part of the bimorph cantilever structure. The electric fields caused by the control voltages cause the piezoelectric bimorphs to move in any desired fashion within ranges determined by the design. The bimorph cantilevers have tips with very sharp points formed thereon which are moved by the action of the control circuit and the piezoelectric bimorphs so to stay within a very small distance of a conducting surface.

Abstract: A method of selectively suppressing the immune system and conferring immunotolerance against a specific antigen by interferring with the L3T4 differentiation antigens on helper T cells is described. Simultaneous administration of a binding moiety specific for the L3T4-equivalent in the subject species and a specific antigen or administration of the antigen subsequent to the binding moiety for L3T4-equivalent within the time required for T-cell recovery results in a diminished ability of the subject to respond immunologically to the antigen, whether or not the subject has been exposed previously to the antigen.

Abstract: An adiabatic pulse suitable for generating selective spin echoes for both MR imaging and spectroscopy is described. The pulse requires no gradient reversal to achieve phase compensation. Like adiabatic inversion pulses the new pulse performs a .pi. rotation for any amplitude exceeding a threshold. Unlike inversion pulses, this pulse leaves no phase variation across the slice. The pulse is actually a composite consisting of a 2.pi. and a .pi. pulse. The 2.pi. pulse merely compensates for the phase of the .pi. phase; it performs no net rotation. This compensation is immune to RF inhomogeneity and nonlinearity.

Abstract: The amplitude of specific spectroscopic components are measured by first finding their frequency in the presence of inhomogeneity. A large stable component, usually the water line, is used as a frequency standard to determine the amount of frequency shift in each voxel. The frequency standard is used to determine the relative frequencies of each of the desired spectroscopic components. In one approach the entire hydrogen spectrum is envelope detected with the beats between the water line and the spectroscopic components used to provide a stable spectrum, immune to inhomogeneity.

Abstract: Magnetic resonance signals are received using a plurality of coils, each sensitive to different but overlapping regions of the volume being studied. The signals are combined so as to cancel in undesired regions of the body and receive net signals from only desired parts of the volume to enhance the signal-to-noise ratio for imaging and spectroscopy.

Abstract: Methods and compostions produced thereby are provided concerning the preparation and use of high specific surface area carbides and nitrides. The carbides and nitrides can be obtained by thermal reduction of oxides in the presence of a source of carbon and nitrogen respectively, with relatively slow progressive temperature increases prior to completion of the reaction, followed by quenching. Novel metastable carbides can be obtained by carburization of nitrides having high surface area, which nitrides can be prepared by the above-described process.

Abstract: An ethylene biosynthesis inhibitor is provided comprising 2-cycloalkyl-1-aminocyclopropanecarboxylic acids or a derivative thereof. By applying the subject compound in an ethylene-production-inhibiting amount, ripening and senescence can be slowed. The compound finds use in conjunction with the inhibition of ripening and improved storage of fruits, vegetables and cut flowers.

Abstract: An electrical transmission line has improved signal transmission characteristics, low attenuation, constant phase and group velocity and constant and nearly ohmic characteristic impedance over a wide frequency band by providing low magnetic loss inductance along with the shunt capacitance of the insulation surrounding the conductors. The low loss inductance can be provided by particulate magnetic material, such as ferrites, homogeneously distributed in the insulating material or alternatively the inductance can be provided by ring(s) of magnetic material concentric with the conductor or by layer(s) of magnetic material when the conductor(s) are flat. A variety of radial or longitudinal profiles of the doping level is possible and can be used in combination with any of these basic loading designs. These concepts can be applied in twisted pair, coaxial or high voltage power transmission and distribution single or three phase cables or strip lines and other breadboard applications.