Air filter device and video projector using air filter device

A video projector comprising:

• an optical system;
• and
• an air filter device arranged in an air inlet through which air is drawn to cool the optical system, wherein the air filter device includes:
• a first air filter that captures dust from the drawn in air and includes a rim, a filtering surface surrounded by the rim, and a grid dividing the filtering surface into a plurality of sections;
• a base including an opening, through which air is drawn, and a frame, which surrounds the opening, wherein the first air filter is coupled to the frame at an upstream side of the opening;
• a cleaner coupled to the base to move along and clean an upstream surface of the first air filter, wherein the cleaner includes a rotation brush that moves along the upstream surface of the first air filter while rotating to remove dust from the first air filter;
• and
• a support that contacts and supports the rim and the frame at a downstream side of the first air filter against pressing forced applied to the first air filter by the rotation brush.