The Panasonic PT-F100NTU projector features Panasonic's advanced Auto Rolling Filter (ARF). The Auto Rolling Filter automatically detects when dust accumulates on the high-efficiency electrostatic filter and impairs performance. The affected section of the filter is wound into the casing, and an unused filter material is automatically put in the airflow path. This way top filtering performance is continually maintained. The Auto Rolling Filter combines with a totally re-engineered airflow path and a hermetically-sealed, dust-free optical system design that ensures that the projector is always clean. This minimizes any brightness loss due to dust accumulation.The result is a projector that maintains superior brightness.