| 摘要 |
PURPOSE:To make it possible to perform highly accurate temperature measurement, by measuring the afterglow characteristic, with a changing point of the intensity of the emitted light of photoluminescence itself as a reference. CONSTITUTION:A light emitting device 1 generates excited light pulses E. The intensity of the excited light of the pulses E suddenly changes stepwise in the middle. The pulses are irradiated on a phosphorescent and fluorescent body 4 through an optical system 3. The fluorescent body 4 generates the photoluminescence F, and its intensity responses the sudden change of the excited light intensity and changes stepwise. A time point P' of said change corresponds to a time point P of the change of the pulse E. A constant difference in steps in the intensity of the emitted light is formed with said time point P' as a boundary. Said time point P' is imparted to a control circuit 2 through an optical system 5 and a light receiving device 6 and detected. Then the stable intensity of the emitted light Io is obtained. With the decrease in the intensity Io after the stop of the excitation, a time point Q at 90% of the intensity Io and a time point R at 10% are detected. Then with the time point P' as time reference, delay time t1 and attenuation time t2 are obtained, and the afterglow characteristic is obtained. |
