Physics Photo of the Week

April 2, 2004

Donald F. Collins

Diffraction from a single slit.  Laser lignt shines through a single narrow vertical slit, but instead of the image of the slit, the image shows a central maximum flanked by alternating light and dark fringes.  This phenomenon can only be explained by treating light as waves.  If light were made of tiny particles, we would see the geometric outline of the slit, with sharp edges and no fringes.
Photo by Elli Bonnett.

At right is the light intensity profile of the diffraction pattern for  an image similar to the one above.  The profile is obtained by means of projecting the image on a CCD camera and plotting the pixel value as a function of position.  This is a project from Physics II, (Phy 252) at Warren Wilson College.