Zoom lighting fixture having multifunction actuator

Abstract

A lighting fixture configured to image a high-intensity beam of light at a distant location with a variable beam spread and a variable image distance. The lighting fixture includes an illuminator mounted on a front projection system. The illuminator includes an elliptical reflector defining two focal points. A lamp is at one of the reflector's focal points, while an aperture of the front projection system is at the reflector's other focal point. The front projection system includes a tubular housing having shutter blades moveably positionable in the aperture to obstruct light passing through the second focal point. A rear lens receives and transmits light emitted by the illuminator, while a front lens is configured to receive light transmitted by the first lens and project it at the distant location. The lenses are contained within the housing. A positioning mechanism is mounted on the housing, and includes a rack and pinion gear device that adjusts the distance between the front and rear lenses in response to the rotation of an actuator. The actuator is configured to slide along a slot in the housing, controlling the translation of the first and second lenses with respect to the illuminator. The actuator is configured with a shielding baffle that covers the slot, and with field angle indicia labeling the actuator with beam spread settings. The actuator is further configured with a locking cam lever that constrains the actuator from being moved with respect to the housing when the locking cam lever is in a locked position.