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. This image also available on FigShare.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1">[1]</a></sup>
<a href="//commons.wikimedia.org/wiki/User:Skoch3" title="User:Skoch3">Skoch3</a>
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>