I recently dismantled a small microplate reader and rather than just scrapping the science element of it i thought i'd offer it here in case someone could re-purpose or reuse it as it's a self-contained unit and is functional.
There is a motorised tray which loads the microplate into the system, a halogen light source passes through a selection of filters. The light then passes to the underside of the microplate through optical fibers, the light from a microplate is then collected by a series of photodiodes in an array. The control board, LCD screen and keyboard control the operation. It connects to a PC through RS232 where a small DOS app controls it entirely through serial commands. I will include the original software on 3.5" floppy disk.
looking for £25 including shipping in the UK or you can collect it from south Manchester for £20