1940

1941 — Speed of light measured using Kerr cell

WC Anderson

Measured the speed of light using a Kerr cell (glass cell filled with a liquid that changes the way light refracts in it when an electric field is applied) which modulated a light beam that then passed through a Michelson interferometer.

1946 — Work on the basis for the Magnetic Resonance Imagine (MRI) machine

Nicolaas Bloembergen

Work on proton spin relaxation times under the guidance of his PhD thesis advisor, Edward Purcell, known as Nuclear Magnetic Resonance (NMR). This later became the basis for Magnetic Resonance Imaging MRI.

1947 — Discovery of the Lamb Shift

Willis Lamb

Discovery of the "Lamb shift," a small shift of energy in two energy levels of the hydrogen atom. Awarded the Nobel Prize in Physics in 1955.

1947 — Research into coherent radiation of electroncs begins

Aleksandr M. Prokharov

Began his research into the coherent radiation of electrons, followed by pioneering work in the field of radio-frequency spectroscopy. Shared the 1964 Nobel Prize in Physics with N. G. Basov and C. H. Townes.

1947 — Instant camera first demostrated

Edwin H. Land

Instant Camera first demonstrated at a meeting of the Optical Society of America in February 1947.

1948 — Paper published on holography

Dennis Gabor

Publishes papers on holography.  Awarded the Nobel Prize in Physics in 1971.

1949 — Formulation of a theory that not all atomic nuclei are spherical

James Rainwater

Experimentally proven in 1953. Jointly awarded the 1975 Nobel Prize for Physics.

1949 — Investigated image transmission through bundles of parallel glass fibers.

Holger Moller Hansen and Abraham C. S. Van Heel

1949 — The first patent for a bar code and system needed to read the code.

Joseph Woodland and Bernard Silver