Part of my independant investigation requires me to carry out an experiment, which when I graph results, would confirm Malus' Law. I plan on using a bulb as my ambient source and two polarizing lenses. I will then measure the intensity of the light after polarization. Hopefully, if i graph the angle of the analyzing polarizer against intensity I will get a Cosine curve. However, I am not quite sure on how to measure the intensity of the light after polarization. Thanks in Advance Any help/advice would be much appreciated. P.S My lecturer has suggested using a irradiance detector which measures in LUX but I am not sure how to convert a value in LUX to a value in W/m^2.