Researchers at the National Institute of Standards and Technology (NIST) have demonstrated a novel method for measuring laser power by reflecting the light off a mirrored scale, which behaves as a force detector.

Although it may sound odd, the technique is promising as a simpler, faster, less costly, and more portable alternative to conventional methods of calibrating high-power lasers used in manufacturing, the military, and research.

Optical power has traditionally been measured by comparing it to electrical units. Researchers aim a laser at a coated detector, measure the detector's temperature change, and then determine the electrical power needed to generate an equivalent amount of heat. This method is extremely accurate but difficult with high-power lasers because it requires slow heating and cooling of massive absorbers. Most absorbers cannot withstand the destructive powers of lasers used for cutting and melting.

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