In 1945, a radar engineer named Percy Spencer was working at Ratheon. He stepped in front of a magnetron, a device that powers radars. He noticed a chocolate bar in his pocket had melted. Later that year, he filed a patent for the first microwave oven
In 1945 engineer Percy Spencer was researching radar at the Raytheon company. He stopped for a minute in front of a magnetron, an electronic vacuum tube that generates high-frequency radio waves. Suddenly feeling a strange sensation, he noticed that the chocolate bar in his pocket was melting.
Intrigued, Spencer placed popcorn kernels near the magnetron; soon popcorn was popping out over the lab floor. Spencer then put a raw egg in a pot in front of the magnetron. The exploding egg splattered a nearby coworker, confirming that microwaves could cook food quickly and unconventionally.
Spencer and other Raytheon company engineers went on to develop the first microwave oven.
The first models (so-called radar ranges), marketed in 1947, weighed 750 pounds and stood almost 6 feet tall.
Early microwave ovens were used exclusively in restaurants, railroad cars, and ocean liners–places where large quantities of food had to be cooked quickly.
It was years before microwave ovens were small and practical enough for home use.
The first domestic microwave oven came on the market in 1955. It cost almost $1,300 and was too bulky to fit in the average kitchen. Thanks to the development in Japan of a smaller magnetron, the first compact and practical microwave oven was introduced in 1967 and cost $495.