Wednesday, September 12, 2012

The speckle-free laser is coming!


Laser speckle is a royal pain in the behind for anyone trying to do 3D imaging by laser triangulation. As I showed in my post back on July 1st, (“Fixes for laser speckle”) a laser line is far from homogenous. The only way to get a solid line is to crank up the exposure – basically to saturate the image – although motion is the low-cost fix.

Speckle reducers are available, at a price, but surely the answer is to have a speckle-free laser. Until now saying that made it sound as though I don’t understand how a laser works, but a team a Yale University is working to make it a reality.

A summary of their work is given in a brief blogspot posting, “Speckle-free laser imaging using random laser illumination” and there’s a link given to the full paper on the nature.com website. Unfortunately I couldn’t get this link to work, but I did track it down on the Yale website: you’ll find it here: http://www.eng.yale.edu/caolab/papers/nphoton12.pdf .

From my brief scan of the very technical paper it’s apparent that this is just a proof-of-concept: actual random laser products are a long way off. But it’s encouraging that such work is happening. The days of dealing with laser speckle may be limited.

No comments: