  In this paper we will report an experimental approach for directly
determining the photogenerated current at individual junctions within the
triple junction solar cell. The method is based on the measurement of different
current-voltage curves; one with the usual illumination system, normally AM0 or
AM1.5G, and the other curves with a light source, having a different spectral
emission. The fitting of all current-voltage curves simultaneously, not
individually, permit us to determine the photogenerated current of three
junctions. It is necessary to have three characteristics or more. An example,
with experimental current-voltage data points, is shown in this work. The main
advantage of this new technique is its simplicity and its easy implementation
at any laboratory with an electrical characterization solar cell system and a
solar simulator. The method has been tested over a large quantity of TJ solar
cells.

Materials Science;Statistical Mechanics