Video projectors are one of the most important tools for creators of interactive installations. The information for projectors is available on various websites, but this 2 part guide will focus on their use in production and interactive environments. Part 1 will focus on the projector as hardware(lenses, lumens, surfaces etc), and part 2 will go into more details on the software and calibration considerations. This will gather some of that disparate knowledge into the important bits you need to make informed decisions about creating a high quality experience. They vary in scale from pocket-sized (or smaller) pico's to refrigerator sized large-venue projectors. They vary in price from a couple hundred dollars, to a couple hundred thousand dollars. In the end, however, essentially all projectors can be described as little more than a bright light element, imaging elements, and a lens. There is something technical about projectors that seems to mystify some people, but it is really important to remember that they are just a flashlight that shoots a square shaped image.

Read more at http://www.creativeapplications.net/tutorials/guide-to-projectors-for-interactive-installations/