1. A blinder, or flipper, is a hinged sheet metal "barndoor" mounted on the edge of a striplight (x-ray), to enable the light to be cut off to a relatively hard line. Typically, a blinder is found on PAR 56 and PAR 64 striplights. Adjustment is by a short length of lightweight chain on each end of the striplight. Obviously only useful when the fixture is hanging and not used as a groundrow. A notation on the Light Plot should state "Flippers US" or "Flippers DS".
A smaller version of this type of blinder was added by NYC rental shops to Colortran Far Cyc units and Altman Sky-Cyc units to allow the downstage spill of the asymmetric-reflector cyc light to be controlled.
2. Shortened version of audience blinder.