AbstractThis paper presents a proposal for infrared ray emission computed tomography (IRECT). This is a method for visualizing the two‐dimensional physical quantum distributions (e.g., temperature, concentration) on an arbitrary transaxial layer of an object by calculating the infrared radiation intensity emitted from the object as the projection data. To verify the usefulness of this method, an experimental system with pyroelectric detector is developed for measuring flame temperature distribution and this system is applied to a Bunsen flame. The experiments yield good images of thermic intensity distribution in the cross section of the flame. In addition, the usefulness of this method in measuring temperature distribution is confirmed by comparing the results with thermocouple probe measurement.