Channel apparatus for focusing a fluid flow

A focusing channel device which focuses fluid containing micro particles to flow through only a predetermined area so that the micro particles flow in a line, the focusing channel device comprising:

• a nozzle formed by a left wall and a right wall each of which comprises an inclination surface,
• the cross sectional area of the nozzle in vertical direction decreases from the entrance of the nozzle toward the exit of the nozzle, and
• the cross sectional view of the channel in horizontal direction has a shape that is asymmetric for the central line in the length direction,
• wherein the inclination surface of one of the left wall or the right wall, which forms the nozzle, is placed on the entrance of the channel device and the inclination surface of the other wall is placed at a distance L from the entrance of the channel device, wherein the distance L is set by a factor of a diameter of the micro particle.