Gramaldi (April 2, 1618 - Dec. 28, 1663) was an Italian mathematician and physicist who studied the diffraction of light. He observed the image on a screen in a darkened room of a tiny beam of sunlight after it passed pass through a fine screen (or a slit, edge of a screen, wire, hair, fabric or bird feather). The image had iridescent fringes, and deviated from a normal geometrical shadow.
This provided evidence for later physicists to support the wave theory of light.
With Riccioli, he investigated the object in free fall (1640-50), and found that distance of fall was proportional to the square of the time taken. link