Lightconnect, Inc.

First Medical, Inc.

Adeza Biomedical Corporation

Yellowstone Diagnostics Corporation

Other

Neophotonics Corporation

Eric K Gustafson

Rick P Trebino

Asif Aziz Godil

John Lee

Kenneth Allen Honer

Matthew Lawrence

Timothy D Stowe

Nicholas Michael Sampas

Arjuna Ragunath Karunaratne

Michael E Cobb

Yuh-Geng Tsay

Jimmy D Allen

Rajeev Patil

Emanuel Calenoff

Lawrence M Ensler

Yuh-geng Tsay

Stoughton L Ellsworth

A tilting mirror MEMS variable optical attenuator attenuates light over a band of wavelengths with minimum wavelength dependent loss. The attenuator includes a lens that has a wedged input face and is made from a material that has high dispersion. The lens design causes different wavelengths to travel different paths through the attenuator such that wavelength dependent loss is reduced. The attenuator may be designed to have minimum wavelength dependent loss at a specified attenuation greater than zero.

Optical attenuator

A simple and robust heat actuated steering device for use with mirrors and other optical components of optical telecommunications equipment is described, together with systems which implement such devices. The device uses differential heating between two legs of a flexured mount to allow tilting that can be used to steer an optical beam. Disturbances in the optical alignment, caused by temperature changes, of an optical device containing this component can be compensated by measuring the device temperature and using this to determine a command signal, for example as provided through a lookup table, to correct for device misalignment. Techniques for calibrating the device and establishing the correction data are also disclosed.

Heat actuated steering mount for maintaining frequency alignment in wavelength selective components for optical telecommunications

A beam refraction apparatus includes an input fiber carrying an input beam. A wavelength dispersive element is coupled to the input fiber. The wavelength dispersive element spreads the input beam in at least one dimension as a function of wavelength and generates a dispersed beam. A controllable grating reflects the dispersed beam to the wavelength dispersive element and generates a recombined beam. The controllable grating provides a controllable reflectivity as a function of wavelength. An output fiber receives the recombined beam. A collimating optical member is coupled to the input and output fibers. The collimating optical member passes the input beam and the recombined beams in parallel and opposite directions.

Dynamic gain and channel equalizers

An analytical system comprises a frame and movable carriage. An analytical rotor is mounted on the carriage and can be translated among a sample dispensing station, a fluid dispensing station, and a label detection zone. In order to perform assays, the analyzer system requires only the introduction of the analytical rotor, sample, and a volume of diluent solution. Sample within the analyzer is contained at all times within either a sample receptacle or the rotor. The method allows for the sequential addition of sample and diluent in order to perform multiple assay steps and is particularly suitable for performing heterogeneous immunoassays. The use of fluorescent label in the system allows multiple analyte detection reactions to be performed from a single sample applied to a single rotor.

System and methods for performing rotor assays

A technique for making precise spectrophotometric measurements illuminates a sample with two or more modulated light sources at two or more, typically closely spaced, wavelengths. Light from the sources is combined, homogenized, and directed to the sample, and the light from the sample is collected and detected by a photodetector. The optical output powers of two sources are modulated with the same periodicity and with a reversed amplitude. Variations in the concentrations of species in the sample affect the modulation amplitude representing the sum of the optical powers from two sources in such a way as to produce an output signal. That output signal, based on an electrical component varying with a periodicity at the fundamental frequency, provides a measure of the difference in the transmissions (or other optical properties) of the sample at the two wavelengths. Feedback methods, such as null-point detection, provide stable, sensitive measurements. Wavelength-division multiplexing--required for simultaneous measurements at many wavelengths--is achieved by modulating different pairs of sources at different frequencies.

Techniques for measuring difference of an optical property at two

A system is disclosed for measuring immunofluorescence of a thin sample layer mounted on a substrate. A sample is located in a radiation beam having a spacially-varying amplitude, for example a series of nodes and antinodes. The sample layer is small to comparison to the period over which the radiation intensity varies, but the support is large in comparison to the period. Thus, when the sample and support are moved relative to the radiation beam, the fluorescence signal from the sample layer will be significantly affected, while the signal from the support is substantially unaffected. The difference between two measurements at different relative orientations of the source and radiation beam can provide a measure of the fluorescence of the sample layer independent of any background scatter of fluorescence of the support. In a preferred embodiment, relative movement between the sample and radiation beam is provided to subject the sample to a time-varying radiation amplitude, and the fluorescence of the sample is obtained from a varying component of the detected signal.

Immunofluorescence measurement of analytes bound to a substrate and

A reflective biograting consists of an optically flat layer of a transparent composition such as silicon dioxide having a first and second surface, alternating zones of active and inactive binding reagent on the first surface, and a reflective metal layer having a thickness of at least above 1000 .ANG.. The reflective metal layer can be supported on an optically flat surface of a wafer, and the reflective metal can be aluminum, silver, gold, chromium, nickel, titanium or platinum coating on a polished wafer. Preferably, the silicon dioxide layer is formed either by direct sputtering of silicon dioxide or by coating an alkali metal silicate solution on the surface of the reflective metal, optionally containing an aminoalkylsilane and a water-soluble hydroxylated polymer such as a dextran. Alternatively, the reflective support comprises one or more reflective layer units, each reflective layer unit comprising an optically flat layer of silicon, and preferably polysilicon, on a layer of silicon dioxide. Each layer of silicon has a thickness within the range of from 150 to 750 .ANG., from 850 to 1300 .ANG., or from 1700 to 2150 .ANG., and preferably within the range of from 200 to 600 .ANG.. Each layer of silicon dioxide has a thickness within the range of from 800 to 1200 .ANG.. The reflective support is supported on the substantially flat surface of an insoluble support.

Highly reflective biogratings

A solid-phase binding assay that measures interferometrically either antibodies or binding pair antigens bound to a spinning disc on which the complementary antigen or antibody has previously been coated in an alternating pattern of immunologically active and inactive spots. The spinning disc is inserted into one arm of a Mach-Zehnder interferometer and as the disc spins the bound and unbound spots pass one after another through the two light beams causing a periodic phase shift in the light. These phase modulated light beams are then recombined at a beam-splitter converting the phase modulation into an amplitude modulation. The two recombined beams then fall on a photodetector which converts the periodically varying optical power into a periodically varying electrical current whose amplitude is proportional to the amount of bound protein on the surface of the disc and whose modulation frequency is equal to the frequency with which the spots pass through the light beam. If the disc is spinning rapidly and there are many spots around the disc this signal frequency will be much higher than the frequency of the noise due to the disc wobble and the vibrations imparted to the interferometer by the spinning motor.

Solid-phase binding assay system for interferometrically measuring

The assay of the subject invention uses DNA sequences as probes in a nucleic acid hybridization diffraction assay, to detect specific DNA sequences in a sample. Diffraction assay methodologies are applied to determine the presence and amount of analyte. This invention involves a discovery in the areas of supporting surfaces for a biogrid or biograting which provide greatly reduced non-specific hybridization and binding. A preferred process of this invention involves manufacturing a biograting for use in a light diffraction assay, and comprises adhering a uniform layer of hybridizing reagent comprising a nucleotide sequence on a smooth, solid surface and exposing the surface to UV radiation through a shadow mask with a diffraction grating pattern of lines to selectively deactivate the hybridizing reagent, leaving a biological diffraction grating design of lines of active hybridizing reagent. The smooth, solid surface is preferably selected from the group consisting of polysilicon and single crystalline silicon surfaces. The diffraction hybridizing assay method of this invention for determining the presence or quantity of an analyte in an aqueous sample comprises contacting a nucleic acid sequence diffraction biogrid with the sample under proper circumstances and for a sufficient time to permit nucleic acid hybridization between a nucleic acid sequence probe and an analyte; separating the biogrid from the sample; illuminating the biogrid with light from a light source; and determining the light diffracted by the diffraction hybridization assay surface.

DNA probe diffraction assay and reagents

An improved binding assay plate having greatly reduced non-specific binding with proteinaceous reagents comprising a polysilicon surface having a binding reagent adhered thereto, the surface having a coating adsorbed thereon of a proteinaceous non-specific binding inhibitor. This binding assay product is prepared by adhering binding reagent to a polysilicon surface and then treating the surface with the proteinaceous non-specific binding inhibitor. The binding assay method comprises the steps of contacting the polysilicion surface having a primary binding reagent and non-specific binding inhibitor adhered to the surface thereof with a solution containing an analyte with which the primary binding reagent specifically binds for a time sufficient to permit conjugation of analyte with the primary binding reagent and determining the analyte bound to the polysilicon surface. The plate is suitable for both sandwich and competition immunoassays. The reduction of non-specific binding produces a substantial increase in sensitivity.

Polysilicon binding assay support and methods

A diffraction immunoassay method in which a diffraction grating design of non-light disturbing primary binding reagent on an insoluble surface is conjugated with analyte in a sample. If the primary binding reagent-analyte conjugate is light disturbing, a diffraction grating is formed. If the primary binding reagent-analyte conjugate is non-light disturbing, the analyte is further conjugated with a secondary binding reagent which is labeled with a light disturbing material to form a diffraction grating. Light from a narrow band light source is then applied to the surface, and the intensity of beams of diffracted light formed by the diffraction grating is determined. The diffraction immunoassay plate for the method comprises a smooth insoluble surface having on the surface thereof, a diffraction grating design of lines of the primary binding reagent. The diffraction immunoassay apparatus comprises a light source, a platform for supporting the diffraction immunoassay plates in the path of a beam of light from the light source, and at least one light detector positioned to detect light diffracted by the diffraction grating.

Growing community of inventors

Palo Alto, CA, United States of America

Eric K Gustafson