PURPOSE: To prevent the decrease of light on the upper surface of a louver piece by providing a louver, which consists of louver pieces having the V-shaped section and outside surface formed in the reflecting surface, near the projection opening of the lamp illuminator main frame, and covering the upper openings of the louver pieces with the reflecting material.

CONSTITUTION: The illuminator main frame 1 has a projection opening 2 in the lower surface, and lamps 3 are located in the illuminator main frame 1. A louver 4 has relatively deep V-shaped channels 6 having their opening in the upper surface of the louver and becoming narrower toward the lower and has the V-shaped section, and has louver pieces, the outside surface 7, 7 of which are formed in the reflecting surface. The reflecting material 11 for covering the upper openings of the louver pieces 8 is formed, for example, in the grid so as to cover the upper openings of the grid louver pieces 8 made of the metal plates such as the aluminium which surface is formed as a reflecting mirror surface. The light radiated from the lamps 3 is directly radiated or reflected on the reflecting plate 13 and the outside surface 7 of the louver piece 8 or is reflected again on the reflecting material 11, and is radiated from the projection opening of the illuminator main frame 1. Thereby, the illuminator efficiency can be improved.