W.D. Westwood

Bio: W.D. Westwood is an academic researcher from bell northern research. The author has contributed to research in topics: Slab & Waveguide (optics). The author has an hindex of 1, co-authored 1 publications receiving 3 citations.

Novel technique of making graded-refractive-index slab waveguides

Abstract: A novel technique is presented of making graded-refractive-index slab waveguides for integrated optics. Using the dependence of the optical properties on sputtering conditions, any variation in refractive-index profile in a film can be produced.

Variable refractive index and birefringent waveguides by sputtering tantalum in O(2)-N(2) mixtures.

Abstract: Optical waveguides with losses <1 dB/cm at 632.8 nm have been prepared by sputtering tantalum in O(2)-N(2) mixtures. As the fraction of N(2) in the sputtering atmosphere increases, the refractive index of the guides exhibit a sharp maximum and then decreases to a much lower value, and the films become birefringent. Using an oxygen discharge, the indices at 632.8 nm for both TE and TM modes are 2.083 +/- 0.003, but the values are 1.850 and 1.877, respectively, for the highest fraction of nitrogen used. The indices have been measured at wavelengths down to 457.9 nm. For low fractions of N(2), the results are consistent with a decreasing film density and a constant molecular polarizability, but a number of effects, including the birefringence, are inconsistent with this picture. Waveguide structures, such as interconnects, branching waveguides, and layered directional couplers, have been demonstrated using films with different indices. The birefringence has also been verified by observation of interference between TE and TM modes simultaneously coupled into the guide.

Planar waveguide lens, its utilization and method for its manufacture

Abstract: A planar waveguide lens is characterized in that the same is a gradient lens, whereby the refractive index profile transversely to the lens axis extends approximately parabolically. The lens may be constructed to be multi-mode or may be constructed to be single-mode in the spatial direction perpendicular to the lens axis and perpendicular to the axis in which the indicated change of the refractive index profile extends. Grid structures are provided for dividing the light. The grid structures may be permanent, electro-optically produced or acousto-optically produced. For single mode fibers, the grid structures are produced by acoustic surface waves, while for multi-mode fibers, the grid structures are produced by way of acoustical volume waves.