Abstract: A projection display device includes, in a case, a flow path forming member for forming a flow path through which cooling air circulates, an image forming element disposed in the flow path, a fan disposed in the flow path, a cooling element for cooling the cooling air via flow path forming member, a temperature detection element for detecting the surface temperature of flow path forming member, a temperature detection element for detecting the temperature of a space in the case, and a control unit for controlling the cooling element based on the detection results of the temperature detection elements. The control unit controls the cooling element so that the inputs from the two temperature detection elements can be identical.

Abstract: A light-source cooling device is provided that, without adopting a complex configuration, is capable of reducing the temperature difference between the top portion and bottom portion of a light source despite change of the installation orientation. The light-source cooling device of the present invention for cooling a light source (11) is provided with: two ventilation ducts (4and 5) for guiding cooling airflows (13a and 13b) to strike against the light source (11) from opposite directions, and two fans (2and 3) for impelling the cooling airflows (13a and 13b) to two airflow guide units (4and 5).

Abstract: A light-source cooling device is provided that, without adopting a complex configuration, is capable of reducing the temperature difference between the top portion and bottom portion of a light source despite change of the installation orientation. The light-source cooling device of the present invention for cooling a light source (11) is provided with: two ventilation ducts (4and 5) for guiding cooling airflows (13a and 13b) to strike against the light source (11) from opposite directions, and two fans (2and 3) for impelling the cooling airflows (13a and 13b) to two airflow guide units (4and 5).