CASI stands for “complete angle scatter instrument” because it measures right through the specular beam instead of blocking it from the measurement. The instrument was developed in the late 1980’s by a team of engineers led by John Stover as a way to inspect optics for the Stars Wars Program. It then became a product and a number of units were sold around the world. In 1995 TMA was purchased by Schmitt Industries, who sells an improved version of the CASI sporting Windows software and over a dozen wavelengths.
Above is a “marketing version” of the CASI. Notice that you can see the laser beam through the sample even though it does not pass through it.
The recent purchase of Schmitt’s scatter measurement equipment and products includes the right to sell and manufacture CASI and Microscan instruments.