Patent ID: 6618213
Filing Date: 2003-09-09
Classification: F04D,G02B,H04N

Abstract:
A rotary optical filter apparatus integrated with a cooling fan, said rotary optical filter comprising a rotary holder axially supported with respect to a predetermined rotary axis; and an optical filter having a filter face formed so as to exhibit a predetermined optical characteristic, said optical filter being rotated together with said rotary holder while being held by said rotary holder such that said filter face is substantially orthogonal to said rotary axis;wherein said cooling fan is a sirocco type cooling fan comprising a plurality of fan blades, each having a wing-shaped cross section extending radially of said rotary axis, arranged circumferentially of said rotary axis at respective positions outwardly separated from said rotary axis, said cooling fan being supported by said rotary holder so as to be integrally rotatable with said optical filter, said cooling fan inhaling an air from a center part and discharging thus inhaled air from an outer peripheral part due to an action of said fan blades upon rotating, so as to make an airflow along said filter face and cool said optical filter.