<Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> A three - dimensional stereoscopic film (also known as three - dimensional sangu, 3D film or S3D film) is a motion picture that enhances the illusion of depth perception, hence adding a third dimension . The most common approach to the production of 3D films is derived from stereoscopic photography . In this approach, a regular motion picture camera system is used to record the images as seen from two perspectives (or computer - generated imagery generates the two perspectives in post-production), and special projection hardware and / or eyewear are used to limit the visibility of each image to the viewer's left or right eye only . 3D films are not limited to theatrical releases; television broadcasts and direct - to - video films have also incorporated similar methods, especially since the advent of 3D television and Blu - ray 3D . </P> <P> 3D films have existed in some form since 1915, but had been largely relegated to a niche in the motion picture industry because of the costly hardware and processes required to produce and display a 3D film, and the lack of a standardized format for all segments of the entertainment business . Nonetheless, 3D films were prominently featured in the 1950s in American cinema, and later experienced a worldwide resurgence in the 1980s and 1990s driven by IMAX high - end theaters and Disney themed - venues . 3D films became more and more successful throughout the 2000s, culminating in the unprecedented success of 3D presentations of Avatar in December 2009 and January 2010 . </P> <Table> <Tr> <Td> </Td> <Td> This section needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (December 2009) (Learn how and when to remove this template message) </Td> </Tr> </Table>

When did 3d movies first enter the scene
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