Dr. Jackson started to conduct successful experiments in theoretical physics and then started to use her knowledge in physics to start making advances in telecommunications while working at Bell Laboratories. These inventions include developments in the portable fax, touch tone telephone, solar cell, and the fiber optic cables used to provide clarity in overseas telephone calls. She has also helped make possible Caller ID and Call Waiting.

Cited: http://www.black-inventor.com/Dr-Shirley-Jackson.a