When utilized in a flow imaging instrument, calibration beads provide a known data source that can be employed in various self-diagnostic, calibration and quality metric applications for the both the optical system of the flow imaging instrument, as well as the flow cell of the flow imaging instrument....http://www.google.de/patents/US6906792?utm_source=gb-gplus-sharePatent US6906792 - Methods of calibrating an imaging system using calibration beads
