All-sky photoelectric lightning detector apparatus

All-sky photoelectric apparatus for detecting and locating lightning discharges comprising:

• a pair of wafer-like planar detector members disposed horizontally with their vertical axes spaced apart a predetermined distance (D), said members each including means responsive to impinging optical radiations for producing XY quadrature electrical signal outputs corresponding in magnitude to the XY wafer location of the impinging radiation,
• optical means for imaging substantially the entire sky on the detectors whereby a lightning discharge radiation occurring at any sky location is optically imaged simultaneously at a related location on both of said detectors,
• data acquisition means, and
• circuit means coupling said quadrature signal outputs to said data acquisition means, said circuit means including background-filtering means for passing to said acquisition means signal information substantially wholly representative of the optical transients of the lightning discharges,
• said data acquisition means being responsive to said filtered information for providing in real time said lightning discharge location data.