| 摘要 |
PROBLEM TO BE SOLVED: To heighten light emission luminance of an illuminator by heightening efficiency of light incidence from a light source to a light guide body. SOLUTION: The illuminator is constructed so as to accept light outgoing from the light source 21 through a light accepting face 4a of the light guide body 4 and to emit the light from a light emitting face. A reflection preventing film 10 to suppress light reflection is film formed on the light accepting face 4a of the light guide body 4 by seal sticking, vapor deposition, dipping and so on. When refractive indexes of surroundings of the light guide body 4, the reflection preventing film 10 and the light guide body 4 are expressed by n0, n1 and n2 respectively, it is desirable that inequalities n0<n1<n2 hold. Also it is desirable that reflectance of the reflection preventing film 10 is 0.1-5%. |
