Abstract: The invention relates broadly to a fiber optic sensor device, advantageously, a refractive index measurement device. A light emitting member transmits light, preferably coherent light, to a light splitter. The light splitter splits the light into a first portion that is transmitted to a first fiber optic coupler having an input optical fiber member and an optical fiber member having a waist region. A first output optical fiber member emerges from the first fiber optic coupler waist region. The light splitter is positioned to insert light into the first fiber optic coupler input optical fiber member. A reference fiber optic coupler includes an input optical fiber member and an optical fiber member having a waist region. The reference fiber optic coupler is enclosed in a potting medium stable reference of constant refractive index. A reference output optical fiber member emerges from the reference fiber optic coupler waist region.

Abstract: A dynamic vibration absorber for reducing vibrations of a platform induced by an oscillating mass mounted thereon is provided by mounting a mass of equal mechanical resonant frequency as that of the oscillating mass and oscillating this mass in a manner to establish an equal and opposite vibration of the platform, thereby cancelling the vibrations induced by the oscillating mass. In one embodiment, a signal from the oscillating mass representative of the frequency and amplitude of its mechanical oscillation is phase shifted and utilized as a driving signal to the drive motor of the absorber mass. In another embodiment, electrical signals representative of the platform vibrations are detected to provide phase and amplitude vibration error signals. These error signals are applied to a reference signal coupled to the drive motor of the canceller mass causing the oscillations of the canceller mass to induce vibrations in the platform which counter the vibrations induced by the oscillating mass.

Abstract: A multifiber electrical brush formed of an electrically conductive matrix material having plural electrically conducting fiber wires embedded therein and extending therefrom, wherein the fiber wires have a diameter varying from 1 to 120.mu.m, a length on the order of 100 times greater than the diameter thereof, and a packing density between 1-25%. Suitable materials for the fiber wires are platinum, gold, silver, copper, palladium, or niobium which may be embedded in a copper, silver, or other suitable matrix material, or copper embedded in an aluminum matrix. The fiber wires may be provided with a coating of a suitable barrier material on the lateral surfaces thereof as may be required to protect the fiber wires from etching during removal of the matrix material, or to prevent and/or retard interdiffusion between the matrix material and the fiber wire material during annealing or hot-forming of brush stock, and/or to impart improved electrical performance to the resultant electrical brush.