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Cool It, Hot Rod: Improving Early Lasers

Merritt Birky in white shirt and tie leaning over and measuring laser rod distortion

Merritt Birky measuring laser rod distortion at NIST in 1969.

Credit: NIST Digital Collections

In the first decade after the invention of the laser one challenge to improving laser quality was the distortion of a laser’s rod due to absorption of heat during lasing. The heat absorption distorted the rod’s optical characteristics, which reduced the quality of a laser’s beam. In 1969 NIST’s Merritt Birky developed a technique to measure the internal stresses on laser rods during lasing, leading to a better understanding of complex active laser characteristics and to improved laser rod construction.

Released May 1, 2017, Updated May 2, 2017