Patent ID: 8054452

Claim:
A device for measuring stray light in liquids comprising: a casing having at least one flat surface; a light-transmissive flexible tube for transporting a liquid, said flexible tube having a tube wall and being fitted within the casing such that at least one portion of the tube wall is pressed against the at least one flat surface and is thereby flattened; a light emitter having a first optical axis, wherein the first optical axis is substantially perpendicular to the at least one flattened portion of the tube wall; and a light detector having a second optical axis, wherein the first optical axis and the second optical axis form an angle of less than about 90°, wherein the at least one flattened portion of the tube wall comprises a first wall adjacent to the light emitter and the light detector, and a second wall spaced away from the light emitter and the light detector, the first wall and the second wall being parallel to each other, and wherein the second wall further comprises a reflective surface facing the light emitter and the light detector.