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Slide projector

A , the most common form of projector
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A carousel slide projector, the most common form of projector

A slide projector is an opto-mechanical device to view photographic slides. It has four main elements: a fan-cooled electric light bulb or other light source, a reflector and "condensing" lens to direct the light to the slide, a holder for the slide and a focusing lens. Light passes through the transparent slide and lens, and the resulting image is enlarged and projected onto a perpendicular flat screen so the audience can view its reflection. Alternatively the image may be projected onto a translucent "rear projection" screen, often used for continuous automatic display for close viewing.

The resolution and color brilliance of good quality 35mm slides (especially Kodachrome) projected onto a high quality screen far exceed that of modern in-home video.

Common in the 1950s and 1960s households as an alternate to television or movie entertainment, family members and friends would gather, darken the living room and show slides of recent holidays or vacations, an often boring affair that incited heckling, catcalls and sleep.

In-home photographic slides and slide projectors have largely been replaced by low cost paper prints, digital cameras, DVD media, video display monitors and digital projectors.

Types of projector

See also

External link



08-19-2006 15:59:36
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