1337_Padawan:
I picked the QTR-1RC to avoid a ADC
A question how far away from the eye do you want to put the sensor? The distance limits very much what you should actually use.
For myself i use HOA1405 sensors to detect rapid wire vibrations/resonance (from 40Hz to 1500Khz), the distance is like 5 to 10mm (using ADC though).