Efforts were continued on a program to investigate the physical and structural properties of photoemitting materials, to study and develop processing procedures for producing improved photocathodes, and to investigate the possibilities of field induced photoemitters. Sbfilms evaporated from PtSb-beads have higher conductivity and lower light transmission than films evaporated from pure Sb-beads. They also can be oxidized. S-20 cathodes formed on oxidized Sb-films and subjected to a Na-Sb alternation at 220 C have shown higher infrared response than any earlier cathodes. Attempts to produce S-20 cathodes by simultaneous deposition from molecular beam sources yielded a multialkali cathode of low sensitivity. Preliminary experiments on improved molecular beam sources and a control circuit were made. The modified reflection electron diffraction tube was successfully tested using gold as a sample material.