PURPOSE: To make an observer on the ground view the pattern of the dummy light emitting surface arranged at a high position, even in day time and with specific hue in nighttime.

CONSTITUTION: The dummy light emitting surface has an optical filter plate 1 and a reflecting film 4 on its reverse surface, the top surface consists of obliquely front facing-down beltlike surface parts 5A and obliquely front facing-up beltlike surface parts 5B which are arrayed alternately in turn, and the reverse surface has obliquely rear facing-up beltlike reverse parts 3A and obliquely rear facing-down beltlike reverse parts 3B. The obliquely front facing- down beltlike surface parts 5B are smooth in longitudinal section and optical filter plate obliquely front facing-up beltlike surface parts 5A are rough. The obliquely rear facing-up beltlike reverse parts 3A are smooth and the obliquely rear facing-down beltlike reverse parts 3B are smooth, irregular, or uneven. The top surface (reflecting surface of a reflecting film 4 is formed of the reverse surface of the optical color filter plate 1.