The PT-D10000U is the world's first projector with an automatic filter cleaning system. When you switch on the projector, the air filter operates and the brush of the auto cleaning "robot" removes dust from the filter. This prevents the clogging results in malfunctions and other problems. The ACR combines with a totally reengineered airflow path and a hermetic, dust-free optical system design to assure that the air inside the projector is clean at all times. This minimizes any brightness loss due to dust accumulation, thus lowering your maintenance costs and your total cost of ownership.