Research News: Organic nonlinear optical (NLO) materials offer and alternative approach to a blue laser to the inorganic materials described by Ouwerkerk (this issue). The criteria for efficient organic NLO materials which are transparent at both 820 nm, the emmission frequency of GaAs/AlGaAs diode lasers, and 410 nm, the frequency of the frequency‐doubled blue light are discussed with special reference to compounds studied at Philips (e.g. see Figure).magnified image