This is the objective lens assembly ONLY from Sony KES-400A Blu-ray optical pickups.  It includes a precision aspheric lens with a focal length of a couple mm on a X-Z voice coil actuator for focus and tracking in the original Sony PS3 Blu-Ray player.  There's also a zone plate beneath the lens (which can be removed).

The graphics show the top view, top closeup of lens itself, bottom view, bottom closeup of zone plate. and schematic of zone plate.

There must be a use for these things.  People have built really nifty microscopes and other types of scanners from Blu-ray parts.

But there is one simple use: As a beam expander for narrow-beam lasers like HeNes.  In a test with a 1 mm beam, the expansion factor was between 25X and 50X if mated with a convex lens having a 100 mm focal length.

At the very least, there are a couple of tiny really powerful magnets in each one. ;-)  Or just ask your friends to identify what they are. ;-)

Buy-It-Now is for a lot of two (2) objective lens assemblies.

To repeat, these are ONLY the objective lens assembly as pictured, NOT the entire KES-400A optical pickup.  Other parts from KES-400As are available - ask.

Thanks for looking,

--- sam