Sizing projection screens for video projection

The correct size of projection screen used for video images (that will increasingly include text carried on the web), is determined by the distance that the furthest viewer is from the screen.

In my experience of attending meetings in various situations, the screens are almost invariably too small to read web text (assuming corrected vision) if you are at the back of the room. This condition is of course determined by the multimedia designer, and the presenter can do little more than say "Move forward if you have trouble reading the text."

Avoid this problem!

Here is a table showing typical screen sizes for various room lengths.

Also see the related page Determining the throw distance for LCD projectors

Width of screen required vs. the distance to the furthest viewer

16 ft. requires a 50x50 screen (Monitors can often be used in this small-sized room)

20ft. requires a 60x60 screen (actual image: 60in. wide x 45in. tall)

24ft. requires a 70x70 screen (actual image: 70in. wide x 52in. tall)

28ft. requires an 84x84 screen (actual image: 84in. wide x 63in. tall)

32ft. requires an 8ft.x8ft.screen (actual image: 8ft. wide x 6ft. tall)

36ft. requires a 9ft.x9ft. screen (actual image: 9ft. wide x 7ft. tall)

40ft. requires a 10ft.x10ft.screen (actual image:10ft. wide x 7.5ft. tall)

44ft. requires an 11ft.x 11ft. screen (actual image: 11ft. wide x 8ft. tall)

48ft. requires a 12ft.x12ft.screen (actual image 12ft. wide x 9ft. tall)


So that everyone can see the entire video image, always have the bottom edge of the image at least 6ft. above the floor.

The reason for showing the screen size as square, above, when the image is actually rectangular, is to utilize standard transparency projector sizes from screen manufacturers. You just don't need to pull the screen down all the way for video images.

As "16x9 proportion" images become more popular, the sizes above will not apply.

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