A high resolution and nondestructive optical characterization technique called laser beam induced current (LBIC) was utilized to detect electrically active defects in HgCdTe wafers. It was also used to study the opto electronic properties in photovoltaic detector elements for focal plane array without the requirement of any electrical contacts to individual detector elements. The LBIC was detected in HgCdTe wafers. The periodic distribution of LBIC was observed in photovoltaic detector with P N junction array. The uniformity for the performance of the diodes in an array can then be assessed by examining qualitatively the LBIC image and by analyzing quantitatively the profile of LBIC signal corresponding to individual diodes