Eugene Wilson Caldwell

Eugene Wilson Caldwell (1870–1918) was an American engineer, radiographer, and physician who conducted early work on the medical uses of X-rays. A native of Missouri, Caldwell studied engineering at the University of Kansas. After working as an engineer for five years, Caldwell became interested in X-rays in 1897, opening what may have been the first X-ray clinic in New York City.

He taught radiography at University and Bellevue Hospital Medical College and later graduated with a medical degree from that institution. Caldwell was president of the American Roentgen Ray Society (ARRS) in 1907, invented the first portable X-ray machine for use at a patient's bedside, and devised a positioning technique known as Caldwell's view that allowed for X-ray visualization of the sinuses.

He also enhanced X-ray technology to reduce the exposure time required to obtain an image, created a stereoscopic device for X-rays so that they could show depth, and modified an existing stereoscopic fluoroscope for wartime use. In 1917, Caldwell was named chief of the new roentgen ray department at Columbia University, making him one of the first radiology professors in the United States. Like many of those who performed early work with X-rays, Caldwell experienced serious health problems from radiation exposure.

After developing radiation burns and radiation-related cancer, he underwent numerous surgeries, including an arm amputation, shortly before his death. He had been a captain in the Medical Reserve Corps, and he was promoted to major shortly before he died.