The controller 19A sets the correction values C1 to C12 to the respective twelve correctors 19B (step S7). Accordingly, the twelve correctors 19B output operation commands CiMV (i is 1 to 12) multiplied by the correction values C1 to C12. As a result, the light amounts of the LED arrays 400 (1) to (12) are corrected, and the amounts of heat by which the electronic device 500 is heated by the respective LED arrays 400 are corrected. Such correction values may be calculated and set, for example, when the inspection apparatus 10 is shipped from a factory or when maintenance of the inspection apparatus 10 is performed.

As described above, under the condition in which the target temperature represented by the temperature setting signal SV is set, the first thermal images are obtained while the electronic device 500 is heated by lighting (individually) the twelve LED arrays 400 one by one in the area 401. Then, the second thermal image representing the sum of the temperatures for each pixel in the area 401A of the twelve first thermal images is obtained. The second thermal image represents the temperature distribution in a state in which the twelve LED arrays 400 are lighted to heat the electronic device 500. Then, by performing the optimization calculation according to the equation (2) using the temperature T_Total obtained for each pixel in the area 401A in the second thermal image, under the condition in which the target temperature represented by the temperature setting signal SV is set, the combination of the correction values C1 to C12 at which the temperature difference T2 is minimized is obtained and set to the twelve correctors 19B.