Abstract: A cooling device with a thermoelectric conversion element having a heat absorbing surface and a heat releasing surface includes: a heat-absorbing-side heat conductive member connected with the heat absorbing surface in a heat-conductive manner; a heat-releasing-side heat conductive member connected with the heat releasing surface in a heat-conductive manner; a plurality of heat-absorbing-side fin members that is disposed to the heat-absorbing-side heat conductive member, protrudes in an out-of-plane direction from an end surface remote from the heat absorbing surface and extends in a predetermined direction; and a plurality of heat-releasing-side fin members that is disposed to the heat-releasing-side heat conductive member, protrudes in an out-of-plane direction from an end surface remote from the heat releasing surface and extends in a predetermined direction intersecting with the plurality of heat-absorbing-side fin members in plan view.

Abstract: A projector includes: an optical component; a sealed structure that includes an optical component casing accommodating the optical component inside, a cooling device, a plurality of duct members including a flow-path-upstream-side duct member that guides the air from the cooling device to the optical component casing, and a ringed air flow passage defined by the duct members, the optical component casing including an air inlet for introducing air into the optical component casing and an air outlet for exhausting the air to an outside of the optical component casing, the cooling device including a thermoelectric conversion element having a heat absorbing surface that faces an inside of the sealed structure and a heat releasing surface that faces an outside of the sealed structure, the duct members introducing the air into the optical component casing via the air inlet and re-introducing the air that is exhausted from the inside to the outside of the optical component casing via the air outlet again into the op