The inventor of the microwave oven in 1945 was Spencer of the United States. In 1946, Raytheon Company of the United States and Spencer Spencer jointly developed a microwave oven specifically for cooking, and obtained a patent application for using microwaves to cook physical objects. The first microwave oven patent was obtained the following year. In 1947, the world's first household microwave oven was launched. It had a 1700W water-cooled magnetron, weighed more than 340 kilograms, and was fully 6 meters high. When the finished product was inspected, it could only be placed in the Boston Hotel. Its price It is also very expensive - US$3,000. Because its invention came from the inspiration of radar devices, it was first called a "radar wave" stove, and later was renamed a "microwave oven."