Abstract: A sound absorber includes a side surface section (a first wall section) in which a plurality of first holes are provided, the side surface section including a first surface and a second surface, a thin film stuck to the first surface of the side surface section, a partition wall (a second wall section) opposed to the second surface and provided in a position separated from the second surface, at least one second hole being provided in the partition wall, and a porous material provided to be opposed to the second wall section in a position separated from the partition wall.

Abstract: A projector includes an optical element (e.g., liquid crystal panels as light modulation element) as a cooling target, a blast fan (a suction fan) adapted to feed air (outside air) for cooling, a duct adapted to make the air by the blast fan flow, and having an exhaust port (ejection ports) opposed to the optical element, and a furry member provided to an inside wall of the duct.

Abstract: A sound absorber includes a side surface section (a first wall section) in which a plurality of first holes are provided, the side surface section including a first surface and a second surface, a thin film stuck to the first surface of the side surface section, a partition wall (a second wall section) opposed to the second surface and provided in a position separated from the second surface, at least one second hole being provided in the partition wall, and a porous material provided to be opposed to the second wall section in a position separated from the partition wall.