Total internal reflection Fresnel lens and optical system using the same

Abstract

Described is an optical lens having a light-receiving surface facing a light source and a first structured surface opposite a first portion of the light-receiving surface. The first structured surface includes a plurality of first reflecting surfaces and first refractive surfaces. Each of the first refractive surfaces receives light from a corresponding first reflective surface for refractive transmission therethrough. The optical system may further include a second structured surface opposite a second portion of the light-receiving surface. The second structured surface includes a plurality of second refractive surfaces. Each of the second refractive surfaces receives light directly from the light-receiving surface. Where the first and second structured surfaces are included, the first and second portions of the light-receiving surface can be positioned so that light projected from the light source at an angle above a threshold angle falls on the first portion and light at an angle below the threshold angle falls on the second portion.

Dependencies are inferred from the claim text.