Classifying device and method of classification

A method of classifying particles, the method comprising:

• flowing a particles-dispersed liquid into a first tubular channel of a classifying device to classify particles using a centrifugal force,
• wherein the classifying device comprises:
• a microchannel that includes a curved portion including the first tubular channel and a second tubular channel;
• and
• a diaphragm that is provided within the curved portion, and that is located at a position between the first tubular channel and the second tubular channel;
• and
• wherein
• the diaphragm has at least a first apertured group formed in a central region of the diaphragm and a second apertured group formed in a first end region and a second end region of the diaphragm, the central region being sandwiched between the first end region and the second end region,
• the first apertured group and the second apertured group communicate the first tubular channel with the second tubular channel along a direction of the centrifugal force,
• the first apertured group has a mesh, and
• the second apertured group has a mesh that is different in size from the mesh of the first apertured group.