Computer aided design method for enhancement of local refinement through t-splines

Abstract

One embodiment of the present technology provides a the method comprises the steps of: Converting B-spline networks to T-splines, Converting NURBS into T-spline surfaces, Adding control points to local regions, Scaling or optimizing weights across the mesh, and merging between NURBS and T-spline surfaces. The technology overcame some of the issues with implementing simultaneous multiple surface design methodology when dealing with groups of lenses and reflectors, by improving seed patch junction continuity, elimination of ripples and holes, and precisely adding control points where required. In at least one embodiment of the technology, the t-splines topology allowed for refined control over the optical surface. Control points were reduced by conversion of a NURBS into a T-spline. T-splines were used to produce new loft lenses which were further refined and merged to spline patches. In another embodiment of the present technology, the T-spline loft lens network was subsequently optimized through reverse raytracing, bi-directional raytracing, flow-line, optical path, or flux tube approach.