Frerichs received his Ph.D. in physics from the University of Bonn in 1924. He came to Northwestern in 1947 to work as a research investigator in the Department of Physics. In 1952 he joined Professor Huxford's project in the same department. In 1956 Frerichs was appointed to the faculty as a professor of electrical engineering in the Technological Institute. In 1969 he became emeritus. His interests have dealt with ultraviolet research, new light sources, the development of the cadmium-sulfide photoconductive cell, the discovery of infrared-transmitting arsenic-trisulfide glass, low-pressure xenon arc tubes, and the production of superconducting films.