PLANAR GRADED-INDEX (GRIN) PECVD LENS

The authors report the design, fabrication and characterisation of a p lanar gradient index (GRIN) PECVD lens. The PECVD-based heilcon plasma reactor was used to deposit graded layers onto a silicon wafer. Ray t racing and beam propagation methods were used to simulate the periodic refocussing of the nominally parabolic refractive index profile. Prop agation characteristics were measured using a standard prism coupler a nd also by observing fluorescence from a specially doped thin polymer layer spun on to the top of the planar lens.