| 摘要 |
PROBLEM TO BE SOLVED: To suppress errors in approximation generated by a change in wavelength characteristics in company with a change in temperature of an object to be measured by calculating temperature of the object to be measured with use of a specified equa tion from a detection signal corresponding to a radiation quantity of light. SOLUTION: An optical detecting means 1 detects a radiation quantity of light from the object to be measured and outputs a detection signal V. A calculating means 2 calculates temperature T of the object to be measured from the detection signal V supplied by the optical detecting means 1 based on an approximate equation in which the detection signal V is shown as a function of T to the ath power (0<a<1), wherein the function has temperature of the object to be measured as a base. In an equation [1] of Planck's law of thermal radiation, Wλ=C1÷λ<5> exp(C2 /λT)-1 (wherein W is a spectral emmisivity,λis a wavelength, T is temperature, and C1 and C2 are constants) errors are suppressed in such a manner that an influence of a change inλby temperature is absorbed by temperature as a variable, corresponding to fixing ofλ. A relation between V and T is set by making a partλT of the equation [1] corresponding to a term which expresses a function which has an upward concavity, that is, an exponential term having temperature T as a base (an exponent a3 is 0<a3 <1).
|
