Abstract: A readout circuit for IR sensing charge injection devices (CID) is disclosed, the CID comprising a two-dimensional array of dual-gate sensing sites on an InSb or HgCdTe substrate. The novel readout circuit, which operates in the charge sharing mode (CSM) in extracting image information, is modified to correct for the subtractive effect present when the CSM mode is used. The readout circuit includes a plurality of processors, one for each column, from which a single serial output may be obtained by a demultiplexer, and into which signals derived from successive pixel sites on the associated column are coupled. A first quantity representing the subtractive error is obtained without injection from each column line by double sampling during a first interval. A second quantity representing the signal corrected for subtractive error is obtained with injection from a pixel site by double sampling during a second interval, the samples being increased by the error quantity.