Top Hats serve two functions in entertainment lighting: To control light spill or to reduce the viewing angle to the lens. Sometimes poor fixture optics or poorly maintained lenses can cause light to be directed into the audience or onto scenery, and top hats can help control that. It is also often objectionable to the audience or camera to see the bright source of the light and top hats can shield the bright source from view. All black top hats and half top hats are flocked on the interior to reduce light reflection.
Specifications (refer to diagram):