Patent ID: 7638339

Claim:
A method comprising: introducing a process flow into a focusing manifold through a micro-fluidic inlet channel; introducing at least three focusing flows into the focusing manifold through at least three micro-fluidic focusing channels; and focusing the process flow by contacting the process from at least three directions with the at least three focusing flows in the focusing manifold to form a focused process flow that exits the focusing manifold through a micro-fluidic outlet channel; providing an interrogation signal to the process flow after focusing, wherein said focusing comprises focusing the process flow so that all dimensions of a cross section of the focused process flow are not greater than a cross section of the interrogation signal, and wherein the cross section of the focused process flow is tilted away from a first wall of the micro-fluidic outlet channel and is tilted towards a second wall of the micro-fluidic outlet channel, the second wall opposite the first wall.