Measurement setups for reflection measurements with an integrating sphere. Figure 3a shows the setup used to measure the total (diffuse + specular) reflection. The sample is tilted by 4° so that the specularly reflected light hits the surface of the integrating sphere, is scattered and detected. Light scattered at the solar cell surface and light emitted by the solar cell is detected as well. Figure 3b shows the setup for a measurement of diffuse light. The sample is not tilted and the specularly reflected light leaves the integrating sphere through the entrance opening undetected.