feb 1, 1950 - OHP (projector)
Description:
An overhead projector is a machine that has a light inside it and makes the writing or pictures on a sheet of plastic appear on a screen or wall.All of us have seen overhead projectors in person and used it more than once during our elementary days. This type of projector can still be found in the university and in some pubic or private schools.
Added to timeline:
Date:
feb 1, 1950
Now
~ 75 years ago