Light art or the art of light is generally referring to a visual art form in which (physical) light is the main, if not sole medium of creation. Uses of the term differ drastically in incongruence; definitions, if existing, vary in several aspects. Since light is the medium for visual perception, this way all visual art could be considered light art absurdly enough; but most pieces of art are valid and coherent without reflecting on this basic perceptual fact. Some approaches on these grounds also include into light art those forms of art where light is not any medium contributing to the artwork, but is depicted. Thus, luminism[1] may also refer to light art in the above sense, its previous usage point to painterly styles: either as an other label for the Caravaggisti in the baroque, or 19th and 20th centuries, fundamentally impressionist schools.
Concerning light as a medium of art, historically light art is confined to the use of artificial light in artworks. This culminates in the paradoxical situation in which machines producing light environments are not the artworks themselves, but the artwork is how they modulate their environments, based on the conventionally taken-for granted, thus solely reflected fact that light is what constitutes our environment.[2]
In the broad sense, of which Gerhard Auer stated in 2004:
"An uncertified term: Light Art had naturalised itself recently, without being fit for a term of either a genre, nor a style: in many symbiotic relations, light plays too many roles, and artificial light made itself only the source of inspiration instead of naming it in the countless isms that are drawing on it."[3]
Any artwork containing something that emits any light may be considered as a piece of light art.