Abstract: A particle characterization apparatus and corresponding method is disclosed. The apparatus comprises a sample cell (14). The sample cell includes: an input opening (26) for receiving a fluid that carries particles flowing along a flow axis, a central acquisition channel (32) hydraulically responsive to the input opening (26) for receiving a first subset of the fluid, a pair of lateral bypass channels (32, 34) hydraulically responsive to the input opening (26) and disposed on either side of the central acquisition channel (32) for receiving second and third subsets of the fluid, a window (36) in the central acquisition channel (32) for illuminating the first subset of the fluid in the central acquisition channel (32),an illumination source (18) positioned to illuminate the fluid in the central acquisition channel (32) through the window (36), and a detector (20) positioned to receive light from the fluid in the central acquisition channel (32) after it has interacted with the fluid.