Signal readout circuit having a two-dimensional focal plane cell array capable of reading out signals with improved resolution

摘要

A focal plane array having unit cells 1 is arranged in two-dimensional array in the directions of rows and columns. Each of the unit cells 1 has a photo detection element 3 and a column selection transistor 4. A plurality of signal readout lines 5 run across the unit cells in the direction of rows. A column selection line 6 runs across the unit cells in the direction of columns to control a conductivity state of the column selection transistor 4. A first shift register 7 is connected with the column selection line 6. A charge integration capacitor 9 and a row selection transistor 11 are connected with the signal readout line 5 through a direct injection gate transistor 8. A second shift register 12 controls a conductivity state of the row selection transistor 11. A reset transistor 14 charges the charge integration capacitor 9. Exchange switches 10 switch by time division the plurality of the signal readout lines 5 to a signal output line 13 for external output.