PURPOSE: To switch a passing beam and a running beam by providing a passing beam filament and a running beam filament on an electric bulb, setting the first focal point on the passing beam filament for a reflecting mirror not covered by a hood and on the running beam filament for the reflected mirror covered by the hood to form a composite reflecting mirror.
CONSTITUTION: A passing beam filament 22 is covered by a hood 21 for the upper half section on the optical axis, and a running beam filament 23 is arranged behind the passing beam filament 22 on the same optical axis. A composite reflecting surface 3 is constituted of the elliptical first focal point reflecting surface 31 having the first focal point at the center of the running beam filament 23 and the second focal point nearly matched with the focal point of a projecting lens 4, the second reflecting surface 32 and the third reflecting surface 33 dividedly arranged on the right and left of the respective filaments 22, 23 and having the first focal point at the rear end of the passing beam filament 22 and the second focal point at the focal point of the projecting lens 4, and the fourth reflecting surface 4 arranged below the respective filaments 22, 23 and having the first focal point at the rear end of the passing beam filament 22 and the second focal point behind the focal point of the projecting lens 4. A passing beam and a running beam can be switched.