A projection booth ( US English ), projection box ( English English ) or Bio box ( Australian English ) is a room or enclosure for the machinery required for the display of movies on a reflective screen, located high on the back wall of the presentation space . It is a movie theater .
During the early cinema period (1895 to the late 1900s approximately), the projector was typically located and operated within the auditorium itself. The move to physically segregated projection booths of the emergence of auditoria specifically designed for the projection of movies, which is caused by a combination of the growing popularity of cinema and increasing interest over the safety of nitrate film . Projection booths that have been segregated and equipped with fire prevention, fighting and containment infrastructure has become a legal requirement throughout the world. A typical example of the regulation that occurred during this period of the fire safety provisions of the Cinematograph Act 1909 in the United Kingdom.
Historically, movie projectors will be included in the process of activation, which will be activated by centrifugal force when the supply reaches an appropriate speed. Two projectors Would Be used, Requiring que la projectionistswitch entre les “operating” and “ready” projectors When a cue mark Was visible on the screen in the upper right corner. The bell alerted the projectionist that attention was required.
Projection booths a standard feature of movie theaters even after the introduction of safety film in the early 1950s, because they are useful for several other purposes. These include isolating the noise produced by opto-mechanical projectors from the audience, providing good Appropriate atmospheric control for the projection and film transportation equipment (Including, in more advanced booths, the use of HEPA air filtration to prevent prevention dust contamination of the movie prints in use ), the provision of work space for the projectionistto prepare for and maintain the equipment, and the isolation of dangerous equipment and infrastructure (eg explosive xenon bulbs and three-phase power ) from untrained members of the public. The windows through which the image is usually made of a special, high grade Glass designed to minimize light loss through absobtion and reflection. They are sometimes called portholes by projectionists, possibly because they are usually much smaller than the windows typically found on the side of the buildings, to be reduced to the level of the auditorium.
Some theaters built or refurbished since the introduction of digital cinema have eliminated the booth altogether, replacing them with a digital projector from the ceiling or rear wall of the auditorium.