A pinhole about 1/8 across in a piece of cardboard will project an image of the sun 15 to 20 feet behind the pinhole screen.
(A pinhole about 1/8 across in a piece of cardboard; will project; an image of the sun 15 to 20 feet behind the pinhole screen)
A pinhole about 1/8 across in a piece of cardboard
will project
an image of the sun 15 to 20 feet behind the pinhole screen