Abstract: A coating system comprises a source of electrically non-insulative coating material, a dispenser for dispensing the coating material toward an article to be coated thereby, an electrostatic high potential for supplying charge to the coating material, means for coupling the high potential supply across the dispenser and the article, a first reservoir, and a first valve. The first valve has a first housing providing first, second, third, fourth and fifth ports, and a first component movable within the first housing and having a first passageway selectively to connect the first port to second port to permit the flow of coating material from the first port to the second port. The first port is coupled to the coating material source, the second port to the first reservoir, and the third port to the dispenser. The second port is coupled to the third port to permit the flow of coating material from the first reservoir to the dispenser. A source is provided for an electrically non-conductive fluid.

Abstract: An optical fiber coupler in which adjacent end portions of two optical fibers are inserted predetermined coupling lengths into recesses in opposite and portions of a tubular waveguide. Each optical fiber comprises an optical fiber guiding core with outer cladding. The tubular waveguide comprises an annular cross-section tubular guiding core with inner and outer cladding. The adjacent end portions of the optical fiber guiding cores are aligned with one another along the axis of the tubular waveguide and are disposed concentrically within it. Their adjacent end surfaces may be spaced apart, or may abut. The optical fibers are fixed with their guiding cores concentrically aligned within the tubular waveguide guiding core by a spacer member. The optical fiber guiding cores and the tubular waveguide guiding core have the same refractive index, for example, 1.500. The spacer member and the cladding materials have a lower refractive index, for example, 1.495.