Abstract: A picture display apparatus and a cooling apparatus used for an optical apparatus for efficiently cooling sections to be cooled through the effective use of air currents supplied from a cooling fan, where in external wall and an internal wall of an air guide section guide rotating air currents generated by the cooling fan to intakes without reducing the air velocity by regulating and directing the air currents in accordance with the shape of the cooling fan and the direction of rotation of the fan. The air currents passing through the air guide section are taken through the intakes into an optical unit and sent to the sections to be cooled including a light valve and a polarizing plate for each color. The sections are thus cooled by the air currents.