Abstract: An optical flow cell is disclosed that includes a flow cell body having an inlet and an outlet with a flow opening therebetween to allow a fluid to pass therethrough. A light entry fixture and a light imaging fixture are transversely carried by the flow cell body to allow viewing of the flow opening, wherein the light entry fixture is positioned at one side of the body and the light imaging fixture is positioned at an opposite side of the body. The fixtures are made from at least some materials different than then flow cell body but having a thermal rate of expansion that matches a thermal rate of the body so as to maintain a predetermined size of the flow opening during temperature fluctuations.

Abstract: An optical flow is disclosed having a shell with a first portion and a second portion. The first portion provides a light entry aperture, and the second portion provides an imaging aperture. An inlet tube and an outlet tube are retained between the first portion and the second portion. A viewing assembly is retained between the first portion and the second portion. The viewing assembly includes a reference plate and a flow channel. The flow channel fluidly communicates with the inlet tube and the outlet tube. The reference plate extends from the shell to serve as a repeatable reference point for properly positioning the optical flow cell.

Abstract: A tribological debris analysis system alternately including a general purpose computer used in conjunction with an imaging device and an illumination delivery system, or a circuit board integrating an embedded processor with the imaging device used in conjunction with the illumination delivery system. The circuit board can be mounted on or coupled to an individual machine. The illumination delivery system includes a bypass conduit connected to the machine under evaluation, an optical flow cell, a pump for pumping a fluid through the optical flow cell connected to the bypass conduit, and a laser for illuminating the fluid flowing through the optical flow cell. The imaging device detects any debris in the fluid illuminated by the laser, and sends information representative of the debris to the general purpose computer or the embedded processor for analysis.