Optical computer

Nonlinear optical properties are of interest due to their potential usefulness for unique optical devices. Some of these applications are frequency-doubling devices, optical signal processing, and optical computers. 

Since 1970 the subject of amoiphous semiconductors, in particular silicon, has progressed from obscurity to product commercialisation such as flat-panel hquid crystal displays, linear sensor arrays for facsimile machines, inexpensive solar panels, electrophotography, etc. Many other appHcations are at the developmental stage such as nuclear particle detectors, medical imaging, spatial light modulators for optical computing, and switches in neural networks (1,2). 

A number of areas in which plastics are used in electrical and electronic design have been covered there are many more. Examples include fiber optics, computer hardware and software, radomes for radar transmitters, sound transmitters, and appliances. Reviewed were the basic use and behavior for plastics as an insulator or as a dielectric material and applying design parameters. The effect of field intensity, frequency, environmental effects, temperature, and time were reviewed as part of the design process. Several special applications for plastics based on intrinsic properties of plastics materials were also reviewed. 

Reimann OA, Kosonocky WF (1965) Progress in optical computer research. IEEE Spectrum 2 181... 

Optical Computing Digital and Symbolic, edited by Raymond Arrathoon... 

Optical computation, 6 67-68 Optical configuration, amino acids, 2 564-565... 

Whilst trae 3D photonic band gap materials operating in the microwave and millimetre range have been produced, those operating in the visible region of the spectrum are still awaited. When this eventually happens the optical computer will no longer be a pipe dream. 

G. A. Johnson, M. Dewhirst, Three-dimensional imaging of xenograft tumors using optical computed and emission tomography, Med. Phys. 33 (2006) 3193-3202. 

William Nunley and J. Scott Bechtel Integrated Optical Circuits and Components Design and Applications, edited by Lynn D. Hutcheson Flandbook of Molecular Lasers, edited by Peter K. Cheo Flandbook of Optical Fibers and Cables, Hiroshi Murata Acousto-Optics, Adrian Korpel Procedures in Applied Optics, John Strong Flandbook of Solid-State Lasers, edited by Peter K. Cheo Optical Computing Digital and Symbolic, edited by Raymond Arrathoon... 

Dramatic improvements in instrumentation (lasers, detectors, optics, computers, and so on) have during recent years raised the Raman spectroscopy technique to a level where it can be used for species specific quantitative chemical analysis. Although not as sensitive as, for example IR absorption, the Raman technique has the advantage that it can directly measure samples inside ampoules and other kinds of closed vials because of the transparency of many window materials. Furthermore, with the use of polarization techniques, one can derive molecular information that cannot be obtained from IR spectra. Good starting references dealing with Raman spectroscopy instruments and lasers are perhaps [34-38]. 

The low stability of the magnesium porphyrins has precluded most potential applications. Other metallotetrapyrroles have found industrial uses for oil desulfurization, as photoconducting agents in photocopiers, deodorants, germicides, optical computer disks, semiconductor devices, photovoltaic cells, optical and electrochemical sensing, and molecular electronic materials. A few scattered examples of the use of Mg porphyrins in nonlinear optical studies have appeared" and magnesium phthalocyanines have been used in a few studies as semiconductor or photovoltaic materials" " One of the few... 

Laser Microminiaturization—Target Optical Computer. For many years, scientists have accepted the fact that optical computers would not become a reality until optical components of micro size and exceptional performance equivalent to the already existing electronic switches and circuits could be developed. Thus, the optical compuicr became a major driving force toward the development of optical component. The problem was extraordinarily complex because size reductions of several orders of magnitude were mandalory. 

Rapid and continued developments in electronics, optics, computing, instrumentation, spectroscopy, and other branches of science and technology led to considerable improvements in various methodologies. Due to this revolution in methodology, we are now able to solve problems which were thought to be extremely difficult to solve a few years ago. The new methods enabled us to better characterize foods and enriched our understanding of foods. 

---