| 摘要 |
<p>A front surface 14a of a lens 14 is divided into 48 front surface areas 14a1, 14a2, 14a3 via ridge lines R1 to R5, and a rear surface 14b of the lens 14 is divided into 48 rear surface areas 14b1, 14b2, 14b3 via trough lines T1 to T5. The individual rear surface areas 14b1, 14b2, 14b3 are formed so as to have surface shapes which are set so that light from a predetermined point A which is positioned on a light source 12 is caused to reach zones on the individual front surfaces areas 14a1, 14a2, 14a3 which correspond to the individual rear surface areas 14b1, 14b2, 14b3, the zones each lying centrally inwards apart from the ridge lines which define the circumference of each of the front surface areas.</p> |
