barn door
Plural
barn doors
1
the large sliding door of a barn
2
a device attached to a lighting fixture or camera that controls the direction and spread of light
A barn door is an accessory used with lighting equipment to control the direction and spread of light. It consists of a set of adjustable metal flaps or panels attached to the front of a light. These flaps can be opened or closed to shape the light, focus it on a specific area, or prevent it from spilling into unwanted regions. Barn doors are commonly used in filmmaking and photography to create precise lighting effects, manage shadows, and enhance the overall look of a scene.