Optical device for measuring the turbidity of a liquid

摘要

A turbidimeter having an elongate fluid conducting body with an access opening at one end and spaced fluid inlet and outlet openings with means to connect the body between sections of a fluid conducting line, a plug-like service unit releasably engaged with and normally closing the body, a light emitter, a conducting light pipe conducting light from the emitter to the end of the body remote from the unit and directing light back towards the unit, a first photo cell carried by the unit and receiving light directed by the light pipe, a second photo cell matched with the first photo cell heat sink means to equalize the temperatures of the cells, power supply and signal transmitting means for the emitter and for the cells, said signal transmitting means including means comparing the signals from the cells.