| 摘要 |
PURPOSE:To prevent solar beams reflected by the inner surface from concentrating at one point and make the construction light in weight by using a projection lens which is a Flesnel lens having a cut part on the front. CONSTITUTION:A lens 8 used as a projection lens has an inner surface 8a formed in plumb plane, and Flesnel cut is applied to its front 8b. The focal point F is situated approx. in the middle of the light shutting edge 7 of a light shutting member 6 in its left-right direction. Thereby solar beams 9, 9,... incident on the front 8b of the lens 8 from its front above are dispersed in different directions by this Flesnel lens, which prevents the solar beams outgoing from the front upon being reflected at the inner surface of the lens from concentrating at a certain point a head and below the lighting fixture. At the same time, the thickness in the middle of the lens 8 can be reduced to accomplish making the lens 8 light in the weight. |
