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Barriers to commercialization of optical correlators include the complexity and cost of their manufacture, their large size compared to typical electronic processors, and the cost of their components. Using sub-micron CMOS VLSI fabrication processes it is possible to build the two SLMs and photodetector array of a Vander Lugt correlator on a single silicon die. The correlator's lenses can be fabricated on a single piece of glass using diffractive optics technology and then attached to the CMOS die to form a monolithic assembly. This approach greatly reduces the mechanical degrees of freedom that must be controlled by the correlator's housing thus lowering cost, reducing size, and improving reliability. Here we report on the design and performance of a prototype.

Smart-pixel spatial light modulators (SLMs) with optical inputs and outputs can offer a powerful combination of optical and electronic processing functions. Here we report on work in progress on an experimental FLC-VLSI SLM intended for use in the first Fourier plane of a joint transform correlator (JTC). The JTC SLM is designed to eliminate the unwanted autocorrelation term that normally exists in the JTC's output. One of the JTC's input images is modulated in phase or amplitude causing a modulation term to occur in the intensity of their joint transform. The smart-pixel SLM selectivley responds to the modulation term and displays the result as an image that will pass through the second and final Fourier transform lens (each pixel contains both a photodetector and an optical modulator).

Due to advances in spatial light modulator technology and high-speed imagers, optical correlators are becoming viable for a variety of high-speed image processing applications. However, conventional approaches to assembling correlators produce systems which are costly to manufacture, and which are too large for some uses. We are investigating approaches to the construction of compact, highly integrated correlators that combine ferroelectric liquid-crystal-on- VLSI spatial light modulators, a CMOS imager, and diffractive optical elements.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We report prototype active-matrix liquid crystal spatial light modulators using ordinary silicon integrated-circuit backplanes and incorporating a fast-switching ferroelectric liquid crystal light modulating layer at the backplane's surface. Backplanes reported here utilize a fully- planarized three-metal CMOS process for improved optical throughput, contrast, and light tolerance. We report a 256 X 256 device with 15 micrometers SRAM pixels having 87% fill- factor, optical throughput of 36 - 45%, contrast ratio of 80:1, and electrical rise/fall times of 85 microsecond(s) . We also report DRAM arrays with pixel pitches of 7.5 micrometers and 5.7 micrometers , with fill factors of 75% and 69%, respectively.

The author's stated aim is to teach the principles and techniques of oculoplastic surgery that can be used in daily practice. He has based it on a book that he wrote in 2001, appropriately updated and revised. It is accompanied by a DVD with a running time of approximately 2 hours 10 minutes. The book is well produced and illustrated. It is written in a conversational style as if the author is standing at the reader's side, which may not be to everyone's taste. There is thus some longwindedness but this is compensated for by the detail given, particularly when describing specific operations. Throughout the text there are boxes that usefully summarise key aspects such as operative details and post-operative management, with at the end of each chapter a box listing the key points and a reading list that does include some references to British texts. The book consists of 16 chapters. The first is on basic surgical techniques and although it would undoubtedly be useful for medical students and trainees in the foundation and core surgical training years, surgeons interested in oculoplastic surgery will find it too basic. More useful is the second chapter on surgical anatomy of the orbit, periorbital area and the face, which links well the anatomy with clinical aspects. The other 14 chapters describe the diagnosis and treatment of commonly encountered conditions Some chapters are weaker in content than others. The chapter on the diagnosis of lid lesions is superficial, with little about pathology, and includes advice to use an incisional rather than an excisional biopsy for the diagnosis of malignant melanoma; the chapter on eyelid reconstruction does not give enough detail about commonly used flaps or, crucially, their planning. The DVD shows 20 operations. These are clearly described and are a very useful adjunct to the book. Overall the book would be useful reading for a UK higher surgical trainee studying for the FRCS examination in a relevant specialty and would be an asset in a departmental library.

The Thanetian Stage in the type area is composed of the Thanet Formation, the Woolwich Bottom Bed and the Oldhaven Beds. The Thanet Formation at the stratotype localities in southeastern England contains calcareous nannoplankton Zones NP 6/7 and NP 8. The Woolwich Bottom Bed and Oldhaven Beds are not zonable in the type area. The marine “Bottom Bed” of the Woolwich and Reading Beds is, however, assignable to Zone NP 9 outside the type area (at Clarendon Hill in Wiltshire).

An analogue of LHRH containing an extension of Gly-Cys at the carboxyl-terminus has been designed to permit reproducible coupling to a suitably modified carrier via a thioether bond. Potential energy calculations indicated that this analogue adopted a conformation in solution virtually identical to the type II′ turn around Gly-6—Leu-7 predicted for native LHRH. Intradermal administration of a conjugate of this analogue with purified protein derivative of tuberculin to male rats previously primed with BCG vaccine rapidly led to complete testicular regression. This adjuvant-free immunisation protocol may represent an alternative to castration for the veterinary control of reproductive function.

A litter bag weight-loss method was used to determine the loss in weight of field-grown Avena sativa shoots and roots. Shoot and root bags were placed in eight quarter-acre paired plots just prior to being sprayed with a 2 lb/acre concentration of Sevin. Litter bag samples were taken at monthly intervals, oven-dried, weighed, and the per cent of remaining material calculated. The results showed a significant decrease in weight loss from bags of shoots in pesticide-treated fields as compared to those in nontreated fields at 41 days after spraying. This difference was no longer significant at 114 days. The root bags showed a significant difference in their weight losses at 71 days after spraying; the difference was no longer significant by 114 days. Dried root and shoot material was digested in 30% hydrogen peroxide and the mineral content (Mg, Fe, K, Ca, Cu) was determined using atomic absorption spectrophotometry. Phosphorus content was determined by the sodium molybdate technique, nitrate nitrogen by specific ion electrode methods, and organic carbon was reported in Walkley-Black values. In most cases the pesticide appli- cation inhibited the release of the minerals analyzed. Those minerals affected returned to a normal level or showed signs of normalcy by 114 days after spraying. The only exception to this was the magnesium in the shoot material. The magnesium ions in this material were immobi- lized to a great degree and showed no signs of recovering by 114 days after spraying.