Keyword: Polar graph
- Hubeňák J.: Modern Photometry – Using a Phototransistor And a Multimeter, Fair 8, České Budějovice 2003A guide on how to make a simple probe for measuring light intensity using a phototransistor. Procedure for measuring the angular dependence of light bulb and LED light intensity (the outcomes are plotted in polar graphs) and a calculation of a quantum efficiency of LED. Making of a polarizing filter from a mobile phone display, a measurement of light bulb and LED light polarization.