stop processing the badges in the second preferred embodiment of this invention the control unit 15 further comprises a heat controller to control heat energy output from the lamp 12 the second embodiment of this invention includes all of the mechanical and electrical elements of the first embodiment therefore the explanations given with respect to the first embodiment are all applicable to the second embodiment the second embodiment further includes a heating rate data stored in the control unit 15 the heating rate data represents the average slope of the temperature curve in fig3 b observed during time period t 0 t 1 while heating the element 7 the control unit 15 calculates an average increase rate of the temperatures it calculated during time period t 0 t 1 the control unit 6 then compares the calculated increase rate with the stored heating rate if the increase rate is lower than the stored heating rate the lamp 12 is outputting less heat energy than it is supposed to be if the increase rate is higher than the stored heating rate the lamp 12 is outputting more heat energy than it is supposed to be therefore if it is determined that the increase rate is lower than the stored heating rate the control unit 15 instructs the power supply 14 during the next heat treatment cycle to raise the heights of the three pulse sent to the lamp 12 the heat energy output from the lamp 12 increases accordingly conversely if it is determined that the increase rate is higher than the stored heating rate the control unit 15 instructs the power supply 14.