Circuit 50 comprises a photodiode 52 with {TAIL ~ anode} 54 and {HEAD ~ cathode} 56 and photodiode 58 with anode 60 and cathode 62 
Circuit 50 comprises a photodiode 52 with { TAIL ~ anode } 54 and { HEAD ~ cathode } 56 and photodiode 58 with anode 60 and cathode 62
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH