Goniometer
A goniometer is an instrument that either measures angles or allows an object to be rotated to a precise angular position.
There are many types, each specialised for its particular application.
The contact angle goniometer was invented by Dr. Zisman of the Bethesda Naval Lab and the first of this type of instrument was built by ramé-hart during the 1960's. Currently, ramé-hart instrument co. builds not only classic manual contact angle goniometers based on Dr. Zisman's design, but also automated instruments that use cameras and software and are used only only for contact angle and surface energy applications, but also surface tension using pendant drop, sessile drop, and myriad other techniques.
Goniometers are used in crystallography for measuring angles between crystal faces. They are also used in X-ray diffraction to rotate the samples. Other versions range from devices which measure human joint movement to ones which determine the angle of contact between a liquid droplet and a flat substrate.