A back light is a lighting source placed behind a subject, aimed toward the camera, to create visual separation between the subject and the background.
In professional audiovisual (AV) production, a back light is one of the core elements of three-point lighting. While the key light provides the main illumination and the fill light softens shadows, the back light outlines the subject, enhances dimensionality, and prevents blending with the background. Back lighting is crucial in environments where clarity and visual polish matter, such as executive video conferencing, commercial broadcasts, and corporate productions. Properly applied, it subtly defines edges and improves the overall professional appearance of the video feed.
Standards for lighting design and production are guided by SMPTE (Society of Motion Picture and Television Engineers) and AVIXA (Audiovisual and Integrated Experience Association).
Back lighting originated in early stage and film production. As cinema advanced, three-point lighting, including the back light, became a standard for achieving depth and consistency. Today, these principles extend to modern AV setups, often using LED and smart lighting systems.