Vol. IV, Memorandum Reports, nos. 28-32, 1949-07 - 1950-02

Work on infrared communication at Northwestern University's Department of Physics was transferred on November 30, 1945, from the Office of Scientific Research and Development Contract OEMsr 990 to the Navy Department, Bureau of Ships, Contract NObs 28373, with Walter S. Huxford, Professor of Physics, remaining as Director. The contract ended on June 30, 1950.

Volume 1, Monthly Progress Reports, contains brief accounts of the various projects carried out under this contract. The volume also includes several longer reports on specific materials, e.g., "Gross-Modulation in the 100 watt cesium lamp," (following the monthly report for December 15, 1946, to January 31, 1947), lists of tubes constructed, and graphs. Reports covering longer periods of time are irregularly included, e.g., 1946-1947, as the monthly report for January, 1948. Vol. 1 concludes with an eighteen page "Contractor's Final Report on Light Beam Communication Systems" covering the period December, 1945, to June, 1950.

Volumes 2-4 contain Memorandum Reports; Vol.5 contains Summary Reports. Vols. 2 and 5 respectively contain complete lists of the Memorandum Reports and the Summary Reports.