On a sunny day (Tue, 22 Mar 2005 01:20:17 GMT) it happened "Marc Reinig"
wrote in :

Babcock's proposed (1953) Eidophor used a mirror covered with a film of oil
scanned by an electron beam to change the local slope.

It was never implemented, however.
We had an Eidophor TV projector in the TV studio, BIG machine, BW, sixties.