
This one also costed me the most unfortunately...
It's a Collimation D40.592 Optical Encoder keyboard

It was used on the Compucolor 8001 and Intecolor 8001
http://oldcomputers.net/compucolor-8001.html
Yep, yet another optical keyboard, except this one is more crazy than the Burroughs one. It uses 10 LED, photo resistor pairs (seems like the max configuration is 14) to determine which key is being pressed.
This is done by blocking a "unique" sequence of LEDs that identify the switch with a metal strip attached to the slider.
Somehow...haven't figured it out yet...it achieves 2KRO! (Don't even bother trying for NKRO on something like this

If I can manage to put it back together, I'll post a video later. Maybe even a video of the LEDs if the are visible light.











Keypress

Released


Extruded Aluminium side brackets






Light Sensors

LEDs






The smaller version of the keyboard on the Intecolor 8001

Patents
https://www.google.com/patents/US3818485
Flickr Album
http://www.flickr.com/photos/triplehaat ... 174490175/
Deskthority Wiki Link (still work in progress)
http://deskthority.net/wiki/Collimation_Optical_Encoder