METHOD OF MONITORING LIGHT SIGNALS FROM LIQUID MEDIUM

摘要

In processes for detection and measuring a substance or condition in a fluid medium by the effect of the substance or condition on a light emitting substance, such as luminous microorganisms, disposed in the medium, a method and apparatus is provided for determining the effect of the medium on the light signal due to the medium absorbancy or other factor which is independent of the effect of the substance or condition on the light emitting substance. This is accomplished by deriving from the transmittance of the fluid medium using an external light source the expected transmittance of the fluid medium containing the light emitting substance according to the expression $where\; A\; is\; the\; absorbancy\; of\; the\; fluid,\; c\; is\; the\; concentration\; of\; the\; absorbing\; substance\; and\; D\; is\; the\; mean\; absorbtion\; path\; length\; of\; the\; photons\; emitted.\; The\; expected\; transmittancy\; is\; applied\; to\; the\; observed\; transmittancy\; of\; the\; test\; sample\; to\; obtain\; the\; transmittancy\; of\; the\; test\; sample\; independently\; of\; the\; optical\; effects\; of\; the\; medium.\; A\; cell\; design\; is\; disclosed\; for\; determining\; the\; absorbancy\; of\; the\; fluid\; medium\; using\; a\; single\; instrument.$