| 摘要 |
PURPOSE: To prevent the occurrence of bright lines by arranging a light reflector and a light transmission plate so that at least the space of one part of the light reflector positioned between a light source and the end of the light transmission plate opposed to the light source may be less than the thickness of the end of the light transmission plate. CONSTITUTION: The end of the light reflector 5 covering a linear light source 4 and the end of the light transmission plate 1 opposed to the light source 4 are arranged so that the inner dimension (a) of a space between the ends 11 of the light reflector 5 covering the light source 4 on the plate 1 side, that is, the space between at least partial parts positioned between the light source 4 and the end surface of the light transmission plate 1 in the light reflector 5 may be less than the thickness (b) of the end of the plate 1. An effect is obtained when the inner dimension (a) between the partial parts of the reflector between the light source 4 and the end surface of the plate 1 satisfies the above condition even when the end of the reflector 5 on the plate 1 side is laminated on the surface of the plate 1. Thus, such a phenomenon that the light beam reflected on the reflector 5 is made incident from a surface other than the end surface part of the plate 1 and is off the total reflection condition in the plate 1 is prevented. |
