At least one concave portion 40 is provided as a part of a protrusion 38 of an end portion of a hood body 37a while protruding frontward from the location of a front-end lens surface 34 with a protrusion length shorter than those of the parts other than the concave portion, an inclined surface 44 divergent frontward from the location of the front-end lens surface 34 is provided on the inside surface of at least one of the concave portions 40, and the angle .beta. between the inside inclined surface 44b of the concave portion 40 and the front-end lens surface 34 is larger than the angle .alpha. between the inside surfaces of the other parts adjacent to the concave portion 40 and the front-end lens surface 34.