Patent ID: 8777458

Claim:
A light flux controlling member that emits light from a light emitting element, from a location diagonally in front of an illumination target surface, diagonally with respect to the illumination target surface, a center axis of the light flux controlling member being provided to match an optical axis of the light emitting element, the light flux controlling member comprising: an input surface that receives as input the light from the light emitting element; a total reflecting surface that total-reflects to collect part of the light received as input on the input surface; and an output surface that outputs the light total-reflected on the total reflecting surface and light arriving directly from the input surface, wherein: the input surface is an inner surface of a recess formed on a back surface side to face the light emitting element, and has a first input surface that is located in a bottom part of the recess and a second input surface that is located between the first input surface and an opening edge of the recess; the total reflecting surface is formed between the back surface side and the output surface side and is formed to surround the optical axis, and total-reflects light received as input mainly from the second input surface in the input surfaces, toward the output surface side; the output surface has a first output surface that is formed in a location on an opposite side of the back surface, around the optical axis, and that is provided closer to the illumination-target surface beyond the optical axis, and a second output surface that is provided in a location farther away from the illumination target surface than the first output surface; the second output surface is formed such that, compared to light distribution characteristics of output light from a surface rotating the first output surface through 180 degrees around the optical axis of the light emitting element as a rotation axis, with output light from the second output surface, a greater number of light fluxes travel toward the illumination target surface; the first output surface has an intersection line between a cross section that is perpendicular to the illumination target surface and that includes the center axis, and the first output surface, as a generatrix, and is a curved surface formed by rotating this generatrix in a ±90° angular range around the center axis as the rotation axis; looking at the output surface on a plan view, the second output surface is an inclined surface which is separated from the first output surface along a center line that is perpendicular to the center axis, and in which a vertex side at the same height level as a vertex of the first output surface along the center line is formed, and the height decreases gradually farther from the vertex side; and the first output surface and the second output surface are connected via a pair of erect walls that are line-symmetrical around the center axis.