| 摘要 |
PURPOSE:To prevent the fluctuation of the reproduction level and thus increase the measuring accuracy of the temperature of the measured substance, by increasing the holding time of the peak value of the reference signal in the video signal via the peak holding circuit. CONSTITUTION:The video signal obtained by giving the AC amplification to the output of the infrared ray detector is supplied to input terminal 14 of peak holding circuit 11. This video signal includes the electric signal derived from the infrared rays supplied from the measured substance and the reference black body emerging fixed period. On the other hand, the 1st synchronous signal synchronized with the reference signal is supplied to circuit 11 via terminal 15, and thus the peak value of the reference signal in the video signal is held for the period in accordance with the synchronous signal. At the same time, the 2nd synchronous signal synchronized with the 1st synchronous signal sent from terminal 17 is applied to electronic switch 13. As a result, switch 13 is turned on, and capacitor C is charged by reference power source 19. Thus the reference signal is held at reference voltage Ec within the period of the peak value, and accordingly the DC component is piled on the measured substance signal to perform the DC reproduction. |
