Patent ID: 6888631

Claim:
Apparatus for use in monitoring particles in a liquid flow, comprising: a duct in the form of a pipe section for receiving the liquid flow; light generating means adjacent the pipe section for transmitting light into the liquid flow via a first at least partially light-transmissive part of the pipe section; light-responsive detection means adjacent a second at least partially light-transmissive part of the pipe section for receiving light from the light generating means which light has passed through the liquid flow; processing means for location remotely from said pipe section; means for coupling the processing means with the detection means, the processing means being adapted for processing signals therefrom to provide data relating to particles in the liquid flow; wherein inside said pipe section, each of said first and second at least partially light-transmissive parts has a non-stick coating; the surface of said first at least partially light-transmissive part inside said pipe section is uneven for reducing deposit build-up on said surface.