Abstract: Disclosed is a method for measuring and calculating a current-voltage curve and a current mismatch between junctions of a tandem solar cell, including at least two solar subcells, the method being performed under simulated solar irradiance according to the international standard illumination AM1.5. The method implies the illumination by a first broad-spectral band light source S1 and includes steps for calculating the necessary light intensities of narrow-band second and the third light sources. The steps of the method achieve to determine adapted gains for second and the third light sources, so that the combination of the light sources S21 and S22 provide the same test results of the solar cell as when illuminated with the first light source S1 only. Also disclosed is a solar cell test apparatus configured to realize the method of the invention.

Abstract: Disclosed is a method for measuring and calculating a current-voltage curve and a current mismatch between junctions of a tandem solar cell, including at least two solar subcells, the method being performed under simulated solar irradiance according to the international standard illumination AM1.5. The method implies the illumination by a first broad-spectral band light source S1 and includes steps for calculating the necessary light intensities of narrow-band second and the third light sources. The steps of the method achieve to determine adapted gains for second and the third light sources, so that the combination of the light sources S21 and S22 provide the same test results of the solar cell as when illuminated with the first light source S1 only. Also disclosed is a solar cell test apparatus configured to realize the method of the invention.