An infrared light radiating lamp in which red light emitted from a front
lens is diluted so as to become inconspicuous by emitting a small amount
of visible light from a rim portion of a convex lens so that the lamp
will not be mistaken for a tail lamp or a stop lamp and without causing
glare. A vehicular infrared light radiating lamp is provided with a light
source unit including a convex lens mounted via a lens holder forward of
a reflector in which a light source is mounted. An infrared light
transmitting film is provided on the rear surface of the convex lens. An
infrared light transmitting film-free region is provided on the outer
periphery of the infrared light transmitting film such that white visible
light for diluting the red light emitted from the convex lens is emitted
from the rim portion of the convex lens. Visible light with a high energy
density is blocked by a light shielding member provided on the rear of
the ring-shaped infrared light transmitting film-free region such that
only visible light with a reduced energy density, namely, light dampened
in intensity by reflection from the infrared light transmitting film,
reaches the infrared light transmitting film-free region. Therefore,
visible light emitted from the rim portion of the convex lens with an
adjusted light intensity does not create glare.