| 摘要 |
PROBLEM TO BE SOLVED: To reduce an angle made between light which is emitted from other than a light emission center of a light emission face of an LED light source and is transmitted through a light incident face and a light exit face of a light guide lens, and a central axis line of the light guide lens.SOLUTION: In an LED lighting device 100 in which a light guide lens 2 including a concave incident face and a convex light exit face 2c1 is formed in a nearly rotating body shape, a light emission center 1a1 of a light emission face 1a of an LED light source 1 is arranged on a central axis line 2' of the light guide lens 2; a concave light incident face 2a1 is composed by a conical face with the central axis line 2' as a center; a light exit face 2c1 is formed so that light which is emitted from the light emission center 1a1 and is transmitted through the light incident face 2a1 and the light exit face 2c1 may become in parallel with the central axis line 2'; and a distance DT1a2 between a part 1a2 farthest from the central axis line 2' out of the light emission face 1a and the central axis line 2' is set smaller than a distance DT2a1b between a part 2a1b farthest from the central axis line 2' out of the light incident face 2a1 and the central axis line 2'. |
