[26p-E301-1~12] 3.13 Semiconductor optical devices

[26p-E301-10] Light trapping for photovoltaic cells operating under monochromatic illumination (II)

〇Yasuhiko Takeda¹ (1.Toyota Central R&D Labs.)

Keywords:optical power transmission, optical filter, laser power converter

Multi-junction photovoltaic cells operating under laser illumination used for optical power transmission yield high output voltage required for driving devices. However, the conversion efficiency significantly lowers when the temperature and incident-light wavelength fluctuates, because the current matching among the subcells breaks. The light-trapping structure consisting of an anti-reflection coating or angular-selective filter on the front face and a diffuse reflector on the rear face makes the light-intensity distribution in the cell approximately uniform, and therefore suppresses the lowering in the efficiency.