Lamp unit and projector employing same

Abstract

Cooling air conveyed through a cooling duct 3 is supplied to a discharge lamp 10 via a cooling air exit 21 having a plurality of flow paths 23a to 23c partitioned by a partition plate 22. An air flow direction changeover section 24 changes a flow path through which the discharge lamp is supplied with the cooling air from the cooling air exit. An air flow blocking ball 25 in the air flow direction changeover section moves by its own weight through a guide portion 26 to thereby block the flow path of the cooling air exit. This allows the cooling air to be directed specifically toward an upper side 11a in a direction of gravity of a lamp bulb of the discharge lamp to eliminate a temperature difference, even if a mounting style of the discharge lamp is varied among desk mounting, ceiling mounting, and vertical mounting.

Dependencies are inferred from the claim text.