| 摘要 |
PURPOSE:To enable the accurate measurement of turbidity in a wide range from low turbidity to high turbidity by one measuring instrument, by selectively outputting of the division value of scattered light receiving output and transmitted light receiving output and the transmitted light receiving output by using predetermined turbidity as a boundary. CONSTITUTION:Light, transmitted through a liquid 12 to be measured, in the irradiated light from a lamp 13 and light scattered by the liquid are respectively received by light receivers 15, 16 and light receiving outputs are respectively supplied to head amplifiers 17, 18 while a signal corresponding to a division value obtained by dividing scattered light receiving output by transmitted light receiving output is generated through a divider 19 and a converter circuit 21 and the signal corresponding to the transmitted light receiving output is generated through the converter circuit 20. On the other hand, when transmitted light receiving output reaches the set value of the transmitted light receiving output at a boundary A where scattered light receiving output changes from increase to decrease along with turbidity, a switch 22 is changed over through a control circuit 23. In this case, the division output from the circuit 21 is selected in a low turbidity range S while transmitted light receiving output from the circuit 21 is selected in a high turbidity range T and turbidity in a wide range from low turbidity to high turbidity can be accurately measured by one measuring instrument. |
