| 摘要 |
PURPOSE:To measure accurately the optical radiation power, by feeding back the differential signal between the output of a thermosensitive element and a reference power source voltage to a light absorber to heat the light absorber and squaring the differential signal and taking out the result. CONSTITUTION:A differential voltage (e) between an output E1 of a thermosensitive element 11 such as a thermistor arranged on the rear face of a light absorber 10 and a reference power source voltage ES is amplified by an amplifier 12 to obtain a signal I, and this signal is not only squared in a circuit 13 but also fed back to the light absorber 10 to heat it. A squared output signal I<2> has a linear relation to an incident light energy W1, and the influence of each factor of the system including the light absorber and the thermosensitive element is eliminated, thus making the accurate measurement possible. |
