| 摘要 |
PURPOSE:To make it possible to perform highly accurate measurement, by providing a constitution so that a sensitivity coefficient is corrected by using the value of a ratio between the measured value and the value after a smoothing process. CONSTITUTION:A bare lamp (secondary standard lamp), whose spectral distribution is regarded as the same as that of a sample lamp, is lit, and a luminous intensity value Ii is obtained with said lamp as a sample. The smoothing of the measured value is performed by a computing circuit 10, and the data Ii after the smoothing is stored in a memory circuit 11. For example, Ii' is obtained by an expression I. By obtaining the ratio between Ii and Ii', the correcting value for the error of the spectral sensitivity of each light receiving element is obtained. For this purpose, the computation of an expression II is performed by a computing circuit 12, a calibrating coefficient Ki is corrected, and a new calibrating coefficient Ki' is obtained and stored again in a memory circuit 6. Since the luminous intensity value Ii is computed by the computation of an expression III for the next measurement, the error due to the dispersion in the spectral sensitivity of the light receiving device can be eliminated with respect to the same kind of the sample as the secondary standard sample. |
