Abstract: The fiber-optic pipette (FOP) couples a glass capillary, common syringe and a single optical fiber together to provide for a facile means of achieving long-pathlength capillary spectroscopy. The FOP acquires rapid spectroscopic measurements of small-volume liquid samples, while simultaneously achieving signal enhancements of the collected spectroscopic signal.

Abstract: A system for the in-situ detection of chemicals, including water, in soil comprises: a penetrometer for penetrating the soil, the penetrometer including interior and exterior surfaces, and a window for allowing infrared radiation to be transmitted between the interior and exterier surfaces of the penetrometer; a driver for driving the penetrometer into the soil to a plurality of different depths; a source for providing infrared radiation which passes through the window to irradiate the soil adjacent to the window; an infrared transmitting chalcogenide optical fiber; an optical system disposed within the penetrometer adjacent to the window for transmitting infrared radiation from the source through the window into the soil and for collecting infrared radiation reflected from the soil back through the window into a first end of the chalcogenide fiber; and a spectrometer coupled to a second end of the infrared transmitting chalcogenide optical fiber for receiving and analyzing the reflected infrared radiation pa

Abstract: The present invention is a chemical sensor including a polymer substrate capable of reversible adsorption of an analyte organic compound, a source of Raman excitation radiation, positioned for directing this Raman excitation radiation onto the substrate, thus generating a Raman signal, and a Raman signal detector, positioned for detecting this Raman signal. Another aspect of this invention is the sensing tip of such a sensor, including a polymer substrate capable of reversible adsorption of an analyte organic compound, focusing means for directing excitation radiation onto the polymer substrate to generate a Raman signal from the organic compound, and collection means, for transmitting this Raman signal to a detector. Another aspect of this invention is an array of sensing tips, each using a different polymer substrate selected for selective adsorption of an analyte species, coupled to an excitation radiation source and a detector.

Abstract: A method for producing internally coated glass tube preforms for drawing er optic conductors. The internally coated glass tubes are halogen coated, preferably coated with metal fluorides, so that an optical fiber formed will have a halogen core which conveys light having a wavelength of about 2 to 4 microns, which is in the infrared region, with low attenuation. With one aspect of the method, a carrier gas and a halogenated alkoxide are introduced into a glass tube which has an inner wall and which is surrounded by a resonator for producing a plasma from the halogenated alkoxide in the tube. With another aspect of the method, a blend of a carrier gas, an organometallic compound, and a halogen-containing gas are introduced into a glass tube which has an inner wall and which is surrounded by a resonator for producing a plasma. In both cases, the tube is moved relative to the resonator to form a plasma zone within the tube such that a halide coating is formed on the inner wall of the tube.

Abstract: A refractive index-based sensor uses a light source and an optical fiber to direct an optical beam towards a sensor/environment face at a specific angle. The sensor has a predetermined shape selected such that the light directed into the sensor will have a specific angle of incidence designed to detect a plurality of liquids. A second optical fiber carries the light reflected off the sensor/environment face to a photodetector. The optical beam will either be transmitted through or reflected off the sensor/environment face based upon the refractive indices of the sensor and the environment and upon the angle of incidence of the optical beam. The amount of light reflected is indicative of the refractive index of the material in a given area of the sensor/environment face and, thus, the type of material. By adjusting the angle at which the light is directed to the sensor/environment face, the photodetector response can be calibrated to identify the type of liquid present at the sensor/environment face.