Light travelling through an optical fiber (n=1.44) reached the end of the fiber and exit into air. (a) If the incident angle at the end of the fiber is 30. What is the refraction angle outside the fiber? (b) What happen if the incident angle is 50? In non-metallic materials, absorption and transmission play an important role in their optical properties. a) What colours of light will be absorbed if the material has bandgap energy, Eg= 2.5 eV? b) What colours of light will be transmitted if the material has bandgap energy, Eg= 2.1 eV? c) What is the key principle that determine the absorption and transmission of a non- metallic materials? Consider a p-type Si sample doped with 105 acceptors atoms cm. The p-type Si has dimension of length L (1mm), width W (1mm) and depth D (0.1mm). The sample was illuminated with wavelength 2- 750 x 10 m at light intensity I= 100 W/m. The electron lifetime is 1 us. What is the photoconductivity of the p-type Si? Given that the hole mobility. = 450 x 10 mV's, electron mobility = 1300 x 10' m'V's'. quantum efficiency, n = 1.