The present invention relates to a method for the assessment of quantity and quality parameters of biological particles in a liquid analyte material. The method comprises applying a volume of a liquid sample to an exposing domain from which exposing domain electromagnetic signals from the sample in the domain can pass to the exterior, and exposing, onto an array of active detection elements such as CCD-elements, a spatial representation of electromagnetic signals having passed from the domain, the representation being detectable as an intensity by individual active detection elements, under conditions permitting processing of the intensities detected by the array of detection elements during the exposure in such a manner that representation of electromagnetic signals from the biological particles are identified as distinct from representations of electromagnetic signals from background signals. The exposing domain has an average interior thickness of between 20 μm and 200 μm.