Fibre-optic liq. refractometer e.g. for soln. concn. monitoring

摘要

In a liq. refractometer for measuring the refractive index of a test liq. by evaluating the optical transmission of a light guide which is immersed in the test liq. to form an interface, at which total reflection occurs in an amt. dependent on the refractive index of the test liq., the novelty is that the optical medium of the light guide (2) is a reference liq. (2.2) pref. having a refractive index corresp. to the upper limit of the desired refractive index measurement range.