(under subclass 64.41) Subject matter wherein the determination is made by measuring or detecting the effect of the liquid on light.
SEE OR SEARCH CLASS
250, Radiant Energy, appropriate subclass, for a photocell,
per se, and
574+, for an optical or preoptical system having a liquid in the path thereof wherein the modification of or the emission of the radiant energy resulting from the irradiation of the liquid is tested.
356, Optics: Measuring and Testing,
436, for measuring visible light transmission or absorption of a liquid wherein the test involves no manipulation other than that involved in optical testing.
