Portable RCPCD Apparatus

Richard K. Ahrenkiel and Donald J. Dunlavy, U. S. Patent 8,581,613 issued 11/12/2013, " Transmission-Modulated Photoconductive Decay Measurement System".

S. W. Johnston, and R. K. Ahrenkiel, U. S. Patent 6,369,603 issued on 4/9/02. "Radio Frequency Coupling Apparatus and Method for Measuring Minority Carrier Lifetimes in Semiconductor Materials."

R. K. Ahrenkiel, U. S. Patent 5,929,652 issued 7/27/99. "Apparatus for Measuring Minority Carrier Lifetime in Semiconductor Materials."

R. K. Ahrenkiel and S. W.Johnston, U. S. Patent 6,275,060 issued 0 8/14/01. "Apparatus and Method for Measuring Carrier Lifetimes in Semiconductor Materials."

D. H. Levi, A. J. Nelson, and R. K. Ahrenkiel, U. S Patent 5,541,118 issued 7/30/96. "Process for Producing Cadmium Sulfide on a Cadmium Telluride surface."

R. K. Ahrenkiel, U.S. Patent 4,165,471(1979), "Optical Sensor Apparatus."

R.K. Ahrenkiel and T.J. Coburn U.S. Patent 3,928,870(1975), "Processes and Elements Providing Giant Magneto-Optical Effects."