The design of UV/IR cut-off filter for silicon solar cell

Abstract

In order to increase the reflection of incidence light which its wavelength is less than 350nm and higher than 1120nm (&#955;<350nm and &#955;>1120nm) on the surface of silicon solar cell and show no influence on the transmission of the light in spectral response range (350nm<&#955;<1120nm) of silicon, the IR/UV cut-off filter on encapsulation glass of silicon solar cell was designed. It can make silicon solar cell absorb the incidence light with selectivity. According to the theory of optical film, a computer program was designed. The IR cut-off filter of A[1.05(LMHML)]⁶[1.15(LMHML)]1.15LG on the top surface of encapsulation glass for solar cell was obtained. The transmission curve was plotted for IR cut-off filter. The curve shows: the IR cut-off filter has good selective transmission, most of the light (&#955;>1120nm) is reflected and all of the light (350nm<&#955;<1120nm) is almost transmitted to the solar cell. In the range between 350nm and 1120nm, the weighted transmission coefficient of light is 98.17%. Similarly, the UV cut-off filter of G ^H/₂ L ^H/₂⁷ S on the rear of encapsulation glass for solar cell was obtained. The transmission curve was also plotted. The curve shows: the UV cut-off filter has good selective transmission, the most of light (&#955;<350nm) is reflected and all of the light (350nm<&#955;<1120nm) is almost transmitted to the solar cell. The weighted transmission coefficient of light (350nm<&#955;<1120nm) is 98.65%. The whole coating that combined IR and UV cut-off filter has the best selective transmission, the most of light (both &#955;<350nm and &#955;>1120nm) is reflected and all of the light (350nm<&#955;<1120nm) is almost transmitted to the solar cell. By calculation, we gained the weighted transmission coefficient, T_W=97.49% (350nm<&#955;<1120nm).