What is an ultra-short-throw projector, and why would you want one?
An ultra-short-throw projector or UST is one that needs very little space between it and the projection surface to cast a large format image. This is achieved via ultra-wide lenses and light source and lens arrangement that can be quite challenging to pull off. Generally a projector needs to have a throw ratio of less than 0.4:1 to qualify as UST.
This kind of setup is desirable for a number of reasons. First, there is the question of space. With a traditional projector, you need a pretty big room to get a decent size…