Expansion   This article needs some major expansion on numerous fronts  Techniques that should be added or expanded stereoscopic piv dualplane stereoscopic piv micropiv scanning piv holographic piv  Equipment should be expanded on to include some mention of the optics and lasers utilized  Software and analysis techniques should also be mentioned to complete the entry  I do have experience in the field but havent done large edits before  So if you see a formatting error please point it out