Optical safety of comparative theater projectors.

Traditional movie projectors employing carbon arcs were introduced to movie theaters more than a century ago, and they were replaced during the 1950s by xenon-arc projectors. Today, these arc-lamp film projectors are expected to be replaced by digital laser projectors. Questions have arisen with regard to safety of the new laser-based projectors and about the comparable safety to the xenon-arc projectors that they replace.