Projector, and its filter renewal control method

Abstract

A housing () that accommodates a light source (), a display device (), etc. has an intake aperture () and an exhaust aperture (). A blowing unit () sucks air in through the intake aperture and expels air out through the exhaust aperture. A filter unit () is disposed so that a filter () faces the intake aperture in a predetermined area between a rolling shaft () and a take-up shaft (). A part of the filter facing the intake aperture is renewed by taking-up the filter from the rolling shaft onto the take-up shaft. A control unit () performs control so as to renew the filter for a range that is smaller than an opening area of the intake aperture, when a predetermined renewal condition is determined to be satisfied, based on the output of a detection unit () that detects a specific factor value relating to contamination of the filter, such as a cumulative display time, a temperature, an air pressure, etc. This reduces a noise occurring during the driving of a fan or a change in the rotational speed of the fan, which are associated with automatic filter renewal.