TURBIDIMETER

PURPOSE:To provide a turbidimeter using an integrating sphere type photoelectric light intensity method capable of measuring exact turbidity of an object to be measured without any influence of humidity of the air. CONSTITUTION:When a parallel beam transmitted from a light source lamp 1 is passed through a liquid layer in a specimen cell 6, its beam is divided into the parallel and dispersion ones on the basis of turbidity of the liquid, enters an integrating sphere 8 and only a diffusion transmission light quantity (dispersion light quantity) Td reaches a light receiver D1 of a light dispersion side attached to the integrating sphere 8 regardless of the light incident direction to the integrating sphere 8. In addition, a parallel transmission light quantity Tp of a light receiver D2 of a light transmission side receiving transmission light transmitted from the integrating sphere 8 is caught. The parallel transmission light quantity Tp and the dispersion light quantity Td are measured simultaneously and the degree of turbidity T is calculated as their light ratio from the following formula. T=K(Td/Tp). At this time, when dry gas is allowed to flow in a measuring chamber 7 housed in the specimen cell 6, turbidity can be exactly measured from the dry gas without clouding of the specimen cell 6 even in the case where humidity is high in the atmosphere.