Abstract: Methods and apparatus for evanescent light fluoroimmunoassays are disclosed. The apparatus employs a planar waveguide with an integral semi-cylindrical lens, and has multi-analyte features and calibration features, along with improved evanescent field intensity. A preferred embodiment of the biosensor and assay method have patches of capture molecules each specific for a different analyte disposed adjacent within a single reservoir. The capture molecules are immobilized to the patches on the waveguide surface by site-specific coupling of thiol groups on the capture molecules to photo-affinity crosslinkers which in turn are coupled to the waveguide surface or to a non-specific-binding-resistant coating on the surface. The patches of different antibodies are produced by selectively irradiating a portion of the waveguide surface during the process of coupling the photo-affinity crosslinkers the selective irradiation involving a mask, a laser light source, or the like.

Abstract: An apparatus and method for rapid real time imaging with wavefield energy by inverse scattering using a C.P.U programmed to process data derived from wavefield energy that has been transmitted and scattered by an object so as to reconstruct a wavefield image of the object. Electronic signals are propagated and are transduced into wavefield energy waves which in turn are propagated toward the object. Detector means detect the wavefield energy waves scattered by the object. The detected wavefield energy waves are then electronically processed and input into a high-speed digital computer which may comprise a C.P.U. and/or a C.P.U in combination with an array or parallel processor.

Abstract: Methods and apparatus for evanescent light fluoroimmunoassays are disclosed. The apparatus employs a planar waveguide and optionally has multi-well features and improved evanescent field intensity. The preferred biosensor and assay method have the capture molecules immobilized to the waveguide surface by site-specific coupling chemistry. Additionally, the coatings used to immobilize the capture molecules provide reduced non-specific protein adsorption.

Abstract: Apparatus and method for optically measuring temperature by spectroscopically determining the temperature-induced changes in the wavelength spectrum of light interacting with a semiconductor temperature sensor. The method includes providing illumination from a radiant energy source with a broad wavelength spectrum, guiding the radiant energy to a remote semiconductor sensor, returning the radiant energy after interaction with the semiconductor sensor, and analyzing the returned wavelength spectrum to determine the temperature-induced spectral changes due to the absorption edge of the semiconductor sensor. One embodiment of the invention comprises a quartz-halogen lamp, an optical multiplexer, optical fiber lightguides, a gallium arsenide semiconductor sensor, a fast scan spectrometer, an analog to digital converter and a microprocessor for processing the information of the returned wavelength spectrum for determining and displaying the sensor temperature.

Abstract: A non-metallic fiber-optic device is provided for measuring the level of fluid in a tank, reservoir, or other vessel. Light from a broadband light source is transmitted through a fiber optic waveguide and an optical coupler to an optical pipe sensor which is immersed in the fluid to be measured. The optical pipe sensor includes a monotonically varied diffraction grating in the surface and along the length of the sensor which serves to retroreflect wavelengths of light as a function of the local spacing of the diffraction grating. For light entering the sensor from the waveguide, wavelengths of light corresponding to the local spacing of the diffraction grating above the fluid level are retroreflected, whereas wavelengths of light corresponding to the diffraction grating spacing below the fluid level either escape into the fluid, are absorbed, or are coupled to a return fiber to be detected.

Abstract: A temperature sensor utilizing a semiconductor sensing element which absorbs monochromatic radiant energy as a function of temperature. The apparatus includes a monochromatic radiant energy source, radiant energy guide means, a semiconductor sensing element interposed in the radiant energy guide means and a detector for detecting the intensity of the monochromatic radiant energy transmitted by the semiconductor sensing element. Advantageously, optical fibers may be used as the radiant energy guide means for directing the monochromatic radiant energy to the semiconductor and returning the transmitted radiant energy to the detector. The semiconductor sensing element is fabricated from a suitable semiconductor material such as galium arsenide. Additionally, the semiconductor material can be fabricated as a mirror or reflecting prism so that it serves both as the sensing element and as part of the optical components for the radiant energy guide means.