ABSTRACT
Generally speaking the research and development of photoreceptor materials can, in retrospect, be seen to have occurred in a chronological sequence. For if selenium and its alloys, discussed in Chapter 9, emerged in the 1950s and 1960s (Felty, 1967), then the organic, polymeric-based photoreceptors (Mehl and Wolff, 1964; Gill, 1973; Mort and
Pfister, 1979), discussed in Chapter 10, were created during the 1960s and 1970s. More recently, plasma-deposited amorphous silicon (a-Si:H) and related materials have been developed (Mort et al., 1980; Shimizu et al., 1980; Yamamoto et al., 1981).
