Freshly scanned is this portrait of Dr. William Coolidge. Dr. Coolidge was an American physicist and engineer, who made major contributions to X-ray machines. He was the retired director of the General Electric Research Laboratory when he was photographed by Karsh.

In 1913 he invented the Coolidge tube, an X-ray tube with an improved cathode for use in X-ray machines that allowed for more intense visualization of deep-seated anatomy and tumors. The Coolidge tube, which also utilized a tungsten filament, was a major development in the then-nascent medical specialty of radiology. Its basic design is still in use. Read more (Wikipedia)