Charge pulse to current conversion
I'm going to assume you're interested in the intensity of light (photons/sec) and not photon counting.

Multiplying the intensity of the light by your photodetector's output gain will get you a current.

I've included a schematic for the noninverting transimpedance amplifier below.  I wasn't sure how to hide the values, but the schematic is provided for topology purposes.  Assuming an ideal opamp, the output is R1*I1.  Using your photodetector as the current source, you should be able to get an output voltage that is proportional to the light intensity.

If you wanted to maintain single supply operation, you could use a different reference for the noninverting input than ground.

If you really were interested in photon counting you could convert this into an integrator by replacing R1 with a capacitor.  You'll have to do something about the dark current, but this goes beyond my experience.  My first attempt would be to calibrate it out with some sort of DAC current source.







simulate this circuit &ndash; Schematic created using CircuitLab