Patent ID: 8969784
Filing Date: 2015-03-03
Classification: G02B

Abstract:
1. An optical lens assembly for directing radiation emitted from an emitter, comprising: a primary lens having a vertex and a center axis extending through the vertex in a first direction substantially perpendicular to a tangent of the vertex; and an optical structure arranged at a predetermined distance away from the center axis, the optical structure being substantially axially symmetrical around the center axis; wherein the primary lens is configured to direct a first radiation from the emitter to a first distance from the vertex of the optical lens assembly such that the first radiation is reflected into a detector located adjacent to the emitter when an external object is arranged at the first distance; and wherein the optical structure is configured to direct a second radiation from the emitter to a second distance from the vertex of the optical lens assembly such that the second radiation is reflected into the detector when the external object is arranged at the second distance, and wherein the second distance is approximately less than five percent of the first distance.