"Air hockey" sorting table

The idea behind this is simple: only objects with a low mass/surface area ratio will be suspended, the rest will simply sit still. A table with thousands of tiny holes on say .1" spacing will act to levitate IC's. The table is inclined, so these IC's "float" their way to the end for collection. The other items will sit still once loaded onto the table (from a conveyor), and can be pulled off periodically by a wiper that reciprocates every 5-10 seconds to prevent excessive build up.

Notice further that very small objects (smaller than hole center spacing) will likely also not move. Thus, one could then do an immediate separation on stationary objects based on size quite easily.

An extension of this idea is to have variable spacing of holes to allow sorting by surface area. Thus, you will get a gradient of parts according to surface area by having a small inter-hole spacing at the beginning, and progressively large hole spacing going forward.

The best way to load such a table is likely with a gentle vibratory feed platen that is separated from the table itself by a small gap, spanned by a plastic apron/bridge.