Abstract: Evacuated microspheres, insulating materials constructed from such microspheres, and methods of manufacturing same provide insulation and reduce heat transfer through radiation, conduction and convection. Additionally, an infrared reflective coating is provided on a microsphere surface to reduce radiant heat transfer. A protective exterior coating is also provided to protect an exteriorly applied infrared reflective coating on such a microsphere. Furthermore, the spheroidal geometry of such microspheres restricts heat transfer to point-to-point conduction therebetween. Finally, evacuated microspheres further reduce through-heat transfer within a shell. One embodiment utilizes such evacuated microspheres in constructing an elastomeric roof coating which appreciably reduces cooling and air conditioning power costs for a building. An alternative embodiment utilizes such an elastomeric coating in constructing an exterior paint for a building.

Abstract: A system and method for initializing and calibrating a fiber optic pressure transducer so that a measured intensity of light which varies as a function of pressure can be accurately translated to the value of pressure which produces that value of light intensity. The transducer includes an enclosed sensor tip having a diaphragm which is exposed to atmospheric pressure on the inside and the pressure to be determined on the outside as measurements are taken, the resulting pressure differential producing a related attenuation in light intensity. Calibration according to the present invention is performed by exposing the diaphragm to atmospheric pressure on the outside and sub-atmospheric pressure on the inside while transmitting light through the fiber in the usual manner. The sub-atmospheric pressure is changed gradually as simultaneous measurements are made of the intensity of light returned through the fiber and the actual value of the sub-atmospheric pressure at a number of discrete times.

Abstract: A miniaturized pressure transducer, particularly suited for intravascular blood pressure measurement, utilizing a single optical fiber for transmitting light both to and from a flexible diaphragm having a light-reflecting surface on one side, the opposite side being exposed to and deflected in accordance with the pressure being measured. The end of the fiber through which light is transmitted to and reflected light received from the diaphragm is ground to form a spherical lens integral with the fiber, whereby light passing through the end of the fiber is focused at a predetermined focal point. The fiber is axially positioned so that the center of the diaphragm, which coincides with the lens axis, is at the focal point when the diaphragm is at maximum deflection, i.e., when its opposite surface is exposed to a predetermined, maximum anticipated pressure.