A photodiode (PD) array accurately measures incident optical power on each of the PDs in the array by eliminating the effect of crosstalk between the individual PDs. Crosstalk within the PD array is removed by measuring the current generated by each PD in the array and generating a corrected optical power value for each PD that is based on the measured current for each PD and on coupling coefficients associated with other PDs in the array. The coupling coefficients are determined during a previous calibration procedure.