Patent ID: 9671088
Date: 2017-06-06
CPC Classifications: F21V,F21Y,G02B

Claim:
1. A lens for an illumination device, comprising: an incident surface, an emergent surface, and a reflective surface connected between the incident surface and the emergent surface, wherein the lens comprises: a first axis as an optical axis of the lens; a second axis perpendicular to the first axis and extending in a longitudinal extending direction of the lens, wherein the first axis and the second axis define a symmetrical surface of the lens; and a third axis perpendicular to the symmetrical surface, wherein a first portion of light from a light source is incident upon the incident surface, refracted by the emergent surface, and then emerges to form a first light beam, and a second portion of light from the light source is incident upon the incident surface, reflected by the reflective surface, refracted by the emergent surface, and then emerges to form a second light beam, wherein the first light beam and the second light beam emerge in a direction away from the symmetrical surface, such that, viewed from a cross section perpendicular to the symmetrical surface, no emergent light exists in a predetermined angle range on two sides of the symmetrical surface, wherein the illumination device comprises a lamp cover, the lens is arranged in the lamp cover, the lamp cover comprises a bottom surface, a top surface arranged to be opposite to the bottom surface, and at least two side surfaces connected between the bottom surface and the top surface, wherein the lens is arranged on the bottom surface, and wherein the predetermined angle range is defined by a width of the top surface on the third axis, and wherein a trend of the emergent surface in a cross section perpendicular to the symmetrical surface is determined based on the following parameters: a first vertical distance, d