Throw (projector)

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In film terminology, throw is the distance between a movie projector lens and its screen. It is the distance the image is thrown onto the screen, and it has a large effect on screen size.[ further explanation needed ] Home theatre installations may often have an incorrect[ further explanation needed ] throw distance in the room but this can be corrected by use of a short throw lens. There are also "long throw" lenses available.

Movie projector opto-mechanical device for displaying motion picture film by projecting it onto a screen

A movie projector is an opto-mechanical device for displaying motion picture film by projecting it onto a screen. Most of the optical and mechanical elements, except for the illumination and sound devices, are present in movie cameras.

Home cinema Systematic reproduction of theater surroundings in a home

Home cinema, also called a home theater, a home theatre, and a theater room, are home entertainment audio-visual systems that seek to reproduce a movie theater experience and mood using consumer electronics-grade video and audio equipment that is set up in a room or backyard of a private home. In the 1980s, home cinemas typically consisted of a movie pre-recorded on a LaserDisc or VHS tape; a LaserDisc or VHS player; and a heavy, bulky large-screen cathode ray tube TV set. In the 2000s, technological innovations in sound systems, video player equipment and TV screens and video projectors have changed the equipment used in home theatre set-ups and enabled home users to experience a higher-resolution screen image, improved sound quality and components that offer users more options. The development of Internet-based subscription services means that 2016-era home theatre users do not have to commute to a video rental store as was common in the 1980s and 1990s.

A related measurement, throw ratio, is the ratio of the distance from the lens to the screen (throw) to the screen width. A larger throw ratio corresponds to a more tightly focused optical system.

Throw Ratio = D / W Projector Screen Geometry Throw Ratio.png

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