Patent ID: 8979317
Filing Date: 2015-03-17
Classification: F21K,F21V,F21Y

Abstract:
1. A light flux controlling member for controlling a distribution of light emitted from a light-emitting element, the light flux controlling member comprising: a plate-shaped first lens; and a plate-shaped second lens, wherein the first lens has a first front surface that is one principal surface, a first rear surface that is the other principal surface, and a first side surface that forms a lateral contour of the first lens, wherein the second lens has a second front surface that is one principal surface, a second rear surface that is the other principal surface, and a second side surface that forms a lateral contour of the second lens, wherein the first lens and the second lens are arranged in an overlapping manner so that the first front surface and the second rear surface face each other and that a low refractive index layer having a lower refractive index than the first lens and the second lens is present between the first front surface and the second rear surface, wherein the first lens has a first concave surface that is formed by indenting the first rear surface of the first lens and is configured to allow the light emitted from the light-emitting element to be incident on the first concave surface to generate light to be guided toward the first side surface, wherein the second lens has a second concave surface that is formed by indenting the second front surface of the second lens and is configured to emit or totally reflect the light that is incident on the first concave surface and is transmitted through the first front surface and the second rear surface, and wherein the first concave surface is inclined such that a concave space in the first lens is tapered toward the first front surface.