Patent ID: 8596797

Claim:
A light source device comprising: an arc tube having a light emission portion and a first sealing portion extending from one end of the light emission portion; a first reflection mirror attached to the first sealing portion and having a substantially concave surface for reflecting a light emitted from the light emission portion; and a container which accommodates the arc tube and the first reflection mirror, wherein: the container has a duct unit disposed above the arc tube and extending along a center axis of light reflected by a reflection surface such that a cooling air can flow in a direction opposite to a traveling direction of the light reflected by the reflection surface, and the duct unit includes: a first opening open to the arc tube and disposed at a position shifted toward a traveling direction side from an opening end of the first reflection mirror, a wall portion which forms an edge of the first opening on a side opposite to the traveling direction side as a final end of the duct unit, and an inclined portion disposed in the vicinity of the edge of the first opening on the traveling direction side to bend a flowing direction of the cooling air toward an upper surface opposite to the surface having the first opening, the inclined portion extending away from the first opening in a sloping direction that is obliquely in the traveling direction and toward the center axis of the light reflected by the reflection surface, the upper surface extends over the first opening; a metal plate-shaped member is attached to the upper surface over the first opening such that the cooling air bent by the inclined portion is reflected by the metal plate-shaped member toward the light emission portion.