Percy LeBaron Spencer (9 July 1894 – 8 September 1970) was an Americanengineer and inventor. He became known as the inventor of the microwave oven.

 

Spencer was born in Howland, Maine. His father died in 1897, and his mother left him a short time later. He lived with his aunt and uncle after that. He never graduated from grammar school, but went to work in a mill as an apprentice at age 12, before joining the U.S. Navy in 1912 to learn wireless telegraphy. He joined the Raytheon Company in the 1920s.
 

In 1941, magnetrons, which were used to generate the microwave radio signals that are the core mechanism of radar, were being made at the rate of 17 per day at Raytheon. While working there, Spencer developed a more efficient way to manufacture them, by punching out and soldering together magnetron parts, rather than using machined parts. His improvements were among those that increased magnetron production to 2,600 per day. For his work he was awarded the Distinguished Public Service Award by the U.S. Navy.
 

In 1945, while standing in front of an operating magnetron, a chocolate bar in his pocket melted. He then tested popcorn in front of the magnetron and it quickly popped all over the room. Development of the microwave oven grew out of these observations, and by 1947 a commercial oven was being sold by Raytheon. (Note: He received US patent 2,495,429 out of his invention of the microwave oven.)
 

He became Senior Vice President and a senior member of the Board of Directors at Raytheon. He received 300 patents during his career at Raytheon; a building there is named after him. Spencer was married and had three children, James, John, and George