books.google.comhttp://books.google.com/books/about/Strained_InGaAs_AlGaAs_Quantum_Well_Infr.html?id=rrIhcgAACAAJ&utm_source=gb-gplus-shareStrained InGaAs/AlGaAs Quantum Well Infrared Photodetectors for the Detection of Multiple Colour and Normal Incidence Infrared Radiation