FRESNEL LENS FOR LIGHTING FIXTURE AND LIGHTING FIXTURE HAVING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a Fresnel lens for a lighting fixture improved in utilization efficiency of light from a light source.SOLUTION: A Fresnel lens 10 for a lighting fixture comprises a tabular lens member 11 having one surface as an exit surface 12 and the other surface as an entrance surface 13, a refraction type convex lens 140 in the form of plural stages formed at a center part 14 of the exit surface 12, and a reflection type lens 150 in the form of plural stages at an outside part 15 of the entrance surface 13. Each convex lens is designed so that an optical axis of light exiting from the convex lens 140 of the exit surface 12 extends in a direction inclined to a center optical axis L0 in a center region of the center part 14 and extends in parallel with the center optical axis L0 in an outer edge region of the center part 14. Each reflection type lens is designed so that an optical axis of light reflected by the reflection type lens 150 and exiting from the exit surface 120 extends in a direction inclined to the center optical axis L0.SELECTED DRAWING: Figure 4