This is a picture of the diffraction patter of a He-Ne laser after traveling through an acousto-optic deflector (AOD) made from TeO2 crystal. The AOD was designed for 1064 nm wavelength laser, so the He-Ne was not the appropriate wavelength, but I think these similar patterns were visible with the IR laser (1064 nm), though to a lesser extent. I used the He-Ne to make it visible with naked eye. At the time in 1999, I did not have a digital camera, so this picture is a digitized image from an analog video camera. That's why it's crappy. I didn't crop it so that the electrical outlet is visible to lend some scale.
See also: stub article on wikipedia: http://en.wikipedia.org/wiki/Schaefer%E2%80%93Bergmann_diffraction
original photo upload on wikimedia commons: http://commons.wikimedia.org/wiki/File:AOD_Loops_Schaefer-Bergmann.png