1 Optical applications of organic photochromic polymer systems.- 1.1 Introduction.- 1.2 Potential for erasable optical storage in photochromic polymer systems.- 1.3 Photochromic imaging in ordered systems or in systems exploiting ordering effects.- 1.4 Applications in optical signal processing and in integrated optics.- 1.5 Conclusions.- References.- 2 Spiroxazines and their use in photochromic lenses.- 2.1 Introduction.- 2.2 Chemistry of spiroxazines,...