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Contents: Molecular Beam Epitaxy, Semiconductor Materials and Devices, Quantum Electronics, Semiconductor Physics, Thin Film Physics, Microwave Acoustics, Surface Studies, Electromagnetic Communication, Radiation and Scattering, Plasma Physics, Rarefied Gas Dynamics, Computational Gas Dynamics, Fault-Tolerant Systems and Computer Architecture, Display, Memory, and Computer Terminal research, Applied Computation Theory, Advanced Automation, Information Retrieval Research, Communications, Analog and Digital Circuits, Decision and Control, and Population/Food/Weather Studies.

Contents: Physical Electronics; Computer and Information Systems; and Communication and Control Systems.

Contents: Semiconductor Physics; Thin Film Physics; Microwave Acoustics; Surface Studies; Millimeter Wave Integrated Circuits; Electromagnetic Radiation and Scattering; Plasma Physics; Rarefied Gas Dynamics; Computational Gas Dynamics; Fault-Tolerant Systems and Computer Architecture; Display, Memory, and Computer Terminal Research; Applied Computation Theory; Advanced Automation; Information Retrieval Research; Communications Systems and Signal Processing; Analog and Digital Circuits; and Decision and Control.

Contents: Physical Electronics; Computer and Information Systems; and Communication and Control Systems.

The purpose of this research is to study the problems associated with an experimental read-write, random access optical memory and to demonstrate its feasibility. The memory element employed is the (M sub A) color center in KCl:NaCl. The fact that it is extremely well studied and that the writing wavelength is in the visible range determined its choice for this study. Topics discussed in the report include the following: Color center physics; Diffraction limited focusing and heating effects; Crystal preparation; Thermo electric cooling; Polarization control; Deflection systems; Memory controller; Computer interface; Experimental results.

Contents: Physical Electronics; Computer and Information Systems; and Communication and Control Systems.

Contents: Surface studies; Surface acoustic waves; Plasma physics; Rarefied gas dynamics; Computational gas dynamics; Semiconductor physics; Display, memory, and computer terminal system research; Photodichroic memory for computer applications; Information science; Advanced automation; Information retrieval research; Networks; Control systems; Digital systems; Population dynamics; Thin films., Sponsored in part by Contract N00014-67-A-0305-0021, and Grant NSF-GK-36276. See also report dated Aug 73, AD-765 960.

Work during this quarter includes measurements of memory crystal properties, electron coloration of KCl:NaCl, new system development, and improvement of existing system components., See also AD-750 408.

The maximum information packing density on the memory crystal is determined by the f number and quality of the optical system. The optical system is a multi-element system including lenses, a polarization control cell, and a beam deflector. Each of these elements can cause aberration and distortion of the beam cross section. During this quarter, a study was made of the optical system to determine where the most severe resolution limitations occur.

Research was directed toward the development of a high speed, high density, random access, read-write optical memory system. The memory system is based upon the stable yet optically reversible changes in the polarizing properties of M sub A color centers in Potassium Chloride crystals. The accomplishments reported for this initial one year period are classified into the following three main categories: (1) The perfection of techniques for preparing M sub A centers in the crystals, (2) The design and construction of an experimental random access memory system, and (3) The development of a reliable read-out technique that provides an output signal with a good signal to noise ratio. (Author), See also Quarterly progress report dated Jan 71, AD-718 392.

The document is a quarterly report which reviews the practicality of using color centers in KC1 Crystals as a high speed, memory. This was demonstrated and the design and testing of circuity used in the control system of working model of the memory was carried out. (Author)