To easily increase display quality of light even in a case of a long light guide body. Depth h1 of a first dot (106) is larger than depth h2 of a second dot (108) in the vicinity of a light source, and, as a location comes closer to an end on an opposite side to the light source, depth h1 of the first dot (106) is reduced, and depth h2 of the second dot (108) is increased. Therefore, it is possible to easily increase display quality of light even in a case of a long light guide body.