Calvin Quate was an American electrical engineer who was best known for his many contributions to microscopy. Notably, Calvin developed the scanning acoustic microscope, which uses sound waves to reveal the internal structure of objects.
He also helped to develop the atomic force microscope, an instrument that creates a three-dimensional, nanoscale profile of a surface. The microscope works by measuring the forces between a tiny probe and the surface being analysed. Calvin also made valuable contributions in the field of electron beam devices, and in the development of the acoustic wave correlator.