| 摘要 |
The object temperature (Tobj) is taken from a table of values corresponding to the values (U1,U2) for the values (Tobj) according to a two dimensional mapping. Tolerance compensation is started to determine a corrected value (T'obj) from (Tobj) from the following formula: T'obj = A /* Tobj + B, A and B correspond to correction terms for gain and zero shift memorized at the calibration stage of the thermopile fabrication. In a preferred realization of the device it includes: (a) a bridge divider for polarizing a terminal, of the thermopile assembly, connected to a terminal of the thermistance which produces the voltage (U2) and; (b) an operational amplifier to amplify the voltage at the terminals of the thermopile assembly and producing as output the voltage (U1). Measurement method for thermal compensation of a thermopile assembly fitted in a sensor housing including a thermopile and a thermistance: (a) a thermopile voltage (U1) is generated which is a function of the object temperature (Tobj) and of a temperature (Tth) for the sensor housing and of a second voltage (U2) of the thermistance which is proportional to the temperature (Tth); analogue - numeric conversion of the two voltages (U1,U2); calculation of the object temperature (Tobj) from the numerical voltages (U1,U2), where Tobj is taken from the following formula: U1 = K1 // (Tobj)<3> /* Integral( lambda min to lambda max)((C1 /* lambda )(-5) // exp(C2 // ( lambda /* Tobj) - 1) d lambda . K3 is a constant, C1 and C2 are Planck constants, lambda is the wavelength of electromagnetic radiation, /=Lmin and lambda max are the terminals of the sensors ultra-red filter.
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