Abstract :
The development of selenium photo cells, culminating in the modern single layer CdO cell, is described and the basic working principle of these cells discussed. Mention is made of a new process called ¿Reactive Sputtering¿ which has shed much light on these questions and made the production of single layer cells a practical proposition. Other applications of Reactive Sputtering are briefly described and a few examples are given for the use of CdO selenium cells and of recently developed infra-red sensitive selenium cells.
