Microwave oven

Abstract

A microwave oven comprising a magnetron for emitting microwaves; a heating chamber body for holding food being heated by microwaves from the magnetron; an infrared ray transmitting section provided in the top wall of the heating chamber body for transmitting infrared rays emitted from the food; an infrared ray detecting device disposed over the infrared ray transmitting section and comprising a horn member and an infrared ray detecting element, the horn member being made of material capable of cutting off microwaves and having a hollow extending toward the heating chamber body into which infrared rays are applied from the food and the infrared ray detecting element being so positioned as to detect infrared rays condensed by the hollow, the hollow having a diameter increasing toward the heating chamber body and a minimum opening size smaller than the wavelength of microwaves and having a spread angle so set that only infrared rays emitted from the food may be allowed to reach the infrared ray detecting element and that infrared rays emitted from other regions than the food may be returned after repeated reflection within said hollow without being applied to the infrared ray detecting element; and a processing circuit for calculating the temperature of the food on the basis of a detection signal from the infrared ray detecting device.

Dependencies are inferred from the claim text.