Evaluation of the spatial distribution of series and shunt resistance of a solar cell using dark lock-in thermography

A theoretical approach of using dark lock-in thermography (DLIT) to resolve series and shunt resistance spatial distribution of a solar cell is derived. The resistance distribution can be represented as a simple function of DLIT temperature amplitude and phase distribution under small signal approximation. DLIT experiment using different solar cells was performed and obtained the temperature amplitude and phase images along with the corresponding resistance images.