Patent ID: 11402562

Abstract:
A method of making an illumination system with enhanced light utilization using an optical waveguide and a linear array of discrete side-emitting light emitting diode (LED) packages which provide a light source. The method includes providing an optical waveguide formed from a thin and flexible light transmissive sheet having a light input edge, a patterned light extraction area located at a distance from the light input edge, and a light mixing area located between the light input edge and the light extraction area. The LEDs are arranged on a flexible printed circuit board (PCB) which is positioned parallel to the light transmissive sheet and has a substantial portion of its area disposed in a space between the light input edge and an opposite edge. The method further includes positioning a reflective layer on a light emitting side of the thin and flexible light transmissive sheet and positioning the flexible PCB in a parallel orientation with respect to the first and second broad-area surfaces and in direct or indirect contact with one of the first and second broad-area surfaces.