| 摘要 |
PURPOSE:To improve measurement accuracy and simplify construction by so constituting the device that the light emitted from a single light source is alternately passed through a visible ray filter and an ultraviolet ray filter and is directed to sample water and photodetectors. CONSTITUTION:In measuring the org. polluting components (expressed as DOC herenunder) in the sample water contg. DOC and suspended solid components (expressed as SS hereunder) by an ultraviolet ray absorption method, the light emitted from a light source L is irradiated to the sample water W by being transmitted through a visible ray filter 10 which allows the transmission of the light component having sensitivity only to the SS components, thereafter the output current ratio I1 of photodetectors D1, D2 differing in optical path length is determined. Thence, the light is changed over by a rotary chopper 8 to an ultraviolet ray filter 9 which allows the transmission of the light having sensitivity to both of the SS components and DOC components. The light transmitted through the filter 9 is irradiated to the sample water W, and the output current ratio I2 of both detectors D1, D2 is determined. From the values of I1, I2, DOC is determined by electronic circuits. |
