Re: detector circuit
Since you the are one to design the optical sensor, then i believe you should already have in ur mind what is the specification u like to design for and for what application. The basic design of front Optical system will have Transimpedance Amplifier (TIA) + Limiting Amplifier (LA) + Output Buffer. I would suggest that, you do a preliminary reserch on the photodiode detector, so that you will have some basic idea on what to do in your design. There are many journals/papers available on photodiode detector design.