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Related to film projector: slide projector, Video projector


1. an optical instrument that projects an enlarged image of individual slides onto a screen or wall
2. an optical instrument in which a strip of film is wound past a lens at a fixed speed so that the frames can be viewed as a continuously moving sequence on a screen or wall
3. a device for projecting a light beam



an optical device that forms an image of objects on a diffusing surface that serves as a screen. Projectors are classified as diascopic, episcopic, and epidiascopic, depending on the method used to illuminate the object.

In a diascopic projector, or diascope, an image is formed on a screen by light rays that pass through a transparent object, such as a diapositive or a motion-picture film (see Figure 1). Motion-picture projectors are a type of diascope in which the illuminated transparent object—the motion-picture film—is shifted in a specific manner in order to create the effect of motion on the screen. In a slide viewer, a transparent object is also illuminated by light rays passing through it, but the object itself is viewed through an eyepiece. Diascopes are the most numer

Figure 1. Optical diagram of a diascopic projector: (1) light source, (2) condenser, (3) diapositive, (4) lens, (5) screen

ous and varied type of projectors: there are diascopes for the printing of photographs, viewing diapositives, reading microfilms, and processing aerial photographs. In many modern diascopes, the focusing and changing of the diapositives is accomplished automatically, and the projector may be equipped for sound reproduction.

An episcopic projector (see Figure 2) forms an image of an opaque object on a screen by means of light rays that are reflected and scattered from the object. This category includes instruments for copying topographic maps and projecting illustrations.

Epidiascopic projectors use a combination of the diascopic and episcopic systems and can project images of both transparent and opaque objects.

Figure 2. Optical diagram of an episcopic projector: (1) light source, (2) reflector, (3) object to be projected, (4) lens, (5) mirror, (6) screen

A projector has both mechanical and optical components. The mechanical components provide for proper positioning of objects relative to the optical system, for changing the objects, and for controlling projection times. The optical components perform the projection process and consist of a lighting system with a light source and condenser and a projection lens.


Volosov, D. S., and M. V. Tsivkin. Teoriia i raschet svetoopticheskikh sistem proektsionnykh priborov. Moscow, 1960.
[Ivanov, A. M.] Zarubezhnye liubitel’skie kadroproektory i diaskopy. Moscow, 1968.



(engineering acoustics)
A horn designed to project sound chiefly in one direction from a loudspeaker.
An underwater acoustic transmitter.
One of the lines or rays in a central projection.
Any apparatus for launching a projectile, such as a gun or rocket launcher.
Smooth-bore-type barrel or other unrifled weapon from which pyrotechnic signals, grenades, and certain mortar projectiles are fired.
A rack for launching target rockets.
Special type of gun for projecting antisubmarine projectiles.


1. A lighting unit which concentrates the light within a limited solid angle by means of mirrors and lenses; provides a high value of luminous intensity in one direction.
2. A line dropped perpendicularly from a point to a plane surface.
References in periodicals archive ?
The almost complete absence of camera movement and editing and the minimal movement of the subjects mean that the pulse of the films comes from the flicker of the film projector, which effectively lays down a beat--sixteen per second--that organizes the movement of the grain from frame to frame.
McClure has spoken of wanting to challenge the "hegemony" of the filmstrip in favor of the projector itself, and by his reading, Cage rethinks the film projector as a versatile instrument, situating it as the center of the performance.
Last year the company introduced the cheaper and more compact version of its large-format film projector for the smaller multiplex theater market.
O Cinema Proibido (Ou a Forma de Manipular Memoria Atraves de um Processo de Ausencia) (The Forbidden Cinema [Or the Form of Manipulating Memory Through a Process of Absence]) is similar, but in this case Barateiro makes use of a 16-mm film projector that does not play a film but simply lights a structure on which he has engraved a list of movies censored by the conservative Portuguese regime between the 1930s and the '70s.
Fittingly, Duchampian bicycle wheels, one of which served as the reel of a film projector, punctuated the show.
This imposed pictorial framework has its auditory equivalent in the repetitive rattle of the 16-mm film projector and the train cars.
Debord achieves this remarkable effect by splicing optical track (which gives the white screen and audio) to what appeared to Assayas to be blank perforated magnetic tape--used at the time for sound editing--which is utterly opaque when passing through the gate of a film projector and utterly silent when passing through the optical sound head of a film projector.