Ultra short throw projector

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Introduction

A projector with ultra short throw capabilities allows positioning the project and a connected laptop very close to the screen rather than somewhere back or in the middle of the audience.

Throw ratio is defined as defined as distance from screen divided by the diagonal.

  • Ultrashort throw can be as low as 0.25 : 1
  • Short throw is about 0.4 tp : 1
  • Normal projects are about 1.2 : 1

Let's look at an example:

  • You need to project on a width of 200cm (79), i.e. for a meeting in your office
  • The diagonal of a 16:9 project (what most modern computer screen have) is 229cm (about 90.3). Its height would be 112.5cm
  • 229 * 0.25 means that the projector should sit 57cm away. That is really close, i.e. would probably work from a desk sitting against a wall (80cm width).

Other distances with a ratio of 0.25

  • 300cm (344 diagonal and 168 height): min. distance is 86cm
  • 500cm (574 diagonal and 280 height): distance is 140cm.

Use in poster exhibition spaces:

  • A1 landscape width, 84.1cm: distance is 24cm.
  • A0 landscape width, 118.9cm: distance is 34cm.

However, a minimal distance of 30cm (12) is needed for projectors. Some models may require 45cm (18).

Use

Short throw projectors have the following advantages:

  • fairly easy transportation
  • Have wireless interfaces
  • People can not trip over wires
  • The presenter will not experience the project light in her/his eyes