Hmmmm I'm going to try dc's approach on a similar sensor I also liberated from a printer. Iirc, I did manage to read a part number and even find a data sheet and still didn't get it to work.... Assuming I didn't release magic smoke during my testing (read as: blundering about with wires and batteries) I might actually get it to work. Then all I have to do is find a use for it.
(Always assuming I can still find the darn thing....)