We are working on a new design that improves upon versions 0.9 and 1.0:

• It will have rear-facing LEDs to allow easy readout from both sides of the detector.
• Instead of using a Darlington arrangement as the frontend, we are investigating whether it is possible to directly use a really good operational amplifier. This should have better linearity, temperature stability, and maybe allow calibration.
• Also, it will use an SMD buzzer to further facilitate pick-and-place assembly.

For the frontend amplifier, we are using the µCurrent by EEVblog as a reference.

Do you have any ideas on how to improve the design? Please share them in the comments!