| http://www.w3.org/ns/prov#value | - For this reason, as illustrated in FIG. 16, the anti-reflection film 81 is formed on the light-incident surface 50a of the light-directing plate 50 with a film thickness of ??/4 by vapor-depositing on it a material such as MgF2 having a refractive index of 1.2 to 1.4 by using an EB (Electron Beam) evaporation device.
|
