Martin F. Krafft blogs about looking for advice on buying a “beamer“. He describes the word as meaning a projector in Germany (it also means the same in the Netherlands).
Since the time when I lived in the Netherlands I have been using the word in English, most people immediately understand what it means, and I believe it’s a better option than the word “projector“. The only possible confusion in this regard is the term Beamer is slang for a BMW car. But it’s pretty rare to talk about cars and computer display methods in the same sentence so this shouldn’t be a problem.