Abstract: A Fabry-Perot cavity is formed by a partially or wholly reflective surface on the free end of an integrated elongate channel or an integrated bounding wall of a chip of a wafer and a partially reflective surface on the end of the optical fiber. Such a constructed device can be utilized to detect one or more physical parameters, such as, for example, strain, through the optical fiber using an optical detection system to provide measuring accuracies of less than aboutb0.1%.

Abstract: An optical signal processor having a monolithic prism supporting one or more channels, and constructed from a first glass block joined to a second glass block at a beam splitter interface. The monolithic prism has thin film beam splitters and filters (such as I and Q filters) either deposited directly on the prism or attached to it. The beam splitter interface, and the thin film beam splitters and filters are arranged relative to each other so that a portion of the return-ranging collimated encoded beam from an external optical sensor is reflected to all the filters. And detectors are connected over the filters to detect particular components of the collimated encoded beam which are passed through the respective filters.

Abstract: A lightweight, small size, high sensitivity gauge for indirectly measuring displacement or absolute gap width by measuring axial strain in an orthogonal direction to the displacement/gap width. The gap gauge includes a preferably titanium base having a central tension bar with springs connecting opposite ends of the tension bar to a pair of end connector bars, and an elongated bow spring connected to the end connector bars with a middle section bowed away from the base to define a gap. The bow spring is capable of producing an axial strain in the base proportional to a displacement of the middle section in a direction orthogonal to the base. And a strain sensor, such as a Fabry-Perot interferometer strain sensor, is connected to measure the axial strain in the base, so that the displacement of the middle section may be indirectly determined from the measurement of the axial strain in the base.