A light source bulb is fixedly inserted into a lateral direction to the
optical axis Ax at a position below an optical axis Ax. Accordingly, a
region lateral to the optical axis Ax on a reflection surface of the
reflector can be effectively utilized for light distribution control.
Furthermore, a first additional reflector having a reflection surface of
substantially-spheroidal shape whose first focal point is at a position
coincident with the light source is disposed at a position above the
optical axis Ax. A second additional reflector 36 having a reflection
surface of a substantially-parabolic vertical cross-sectional profile
whose focal point is coincident with a second focal point of the first
additional reflector is disposed at a position below the optical axis. As
a result, light from the light source is illuminated forward without
passing through a projection lens.