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Systems that require multiple coordinated sensors (including sensor fusion) used for ISR, navigation in degraded environments, or infrared countermeasures are constantly trying to increase throughput to carry higher resolution images and video in real-time and with low latency. The need for ever higher throughput challenges system designers on every level, including the physical interface. Simply moving video efficiently from point to point or within a network in itself is a challenge. ARINC 818, the Avionics Digital Video Bus continues to expand into real-time video applications because of its low latency, robustness, and high throughput capabilities.

With the highlights of the high transmission rate, large capacity, strong anti-interference and anti-capture ability, good security and small light, space laser communication becomes an important hotspot. At present, the focus of research of the laser communication system is point to point communication structure. However, from the application point of view, both the realization of space laser communication among multiple points and the establishment of the information transmission network can really have the practical value. Aiming at the problem of space laser communication network, this article puts forward the general idea about optical antenna to achieve multiple tracking goals at the same time. Through the analysis of the optical antenna, and the comparing of the current commonly used mirror driving mechanism, a new mirror driving mechanism is designed. The azimuth motion, containing circular grating feedback, is driven by torque motor，voice coil motor of fan produces pitch motion that has fan-shaped grating feedback, so that compression of the structure size to improve the efficiency of the reflector assembly. Through the establishment of the driving mechanism and the kinematic model of 3D entity, the relationship between the single drive azimuth and pitch angle following the angle of incident light is explained. The biggest ideal view area affecting the optical antenna is obtained by the simulation analysis of the kinematics model using MATLAB. The several factors of field overlap area and blind area offers a theoretical basis for structure optimization and control system for the subsequent optical antenna design.

An effective multi-layer occlusion algorithm is put forward, which is composed of basic point to point occlusion detecting algorithm, status combining algorithm, effective feature point detecting algorithm and continuity optimizing algorithm. The status combining algorithm is designed to increase occlusion detecting algorithm's robustness according to the property that the display status of adjacent points is spatio-temporal piecewise-constant. By selecting virtual edge points with obvious feature on mesh contour to do status detecting and combining computation, higher occlusion detecting accuracy can be gained. By applying continuity optimizing algorithm on virtual points' display statuses, the rendering quality can be improved much. Experiment result proved that this algorithm can realize reliable multi-layer occlusion detection in augmented reality system.

This paper describes a new opto-mechanical scanner that is hopeful for terahertz imaging in security applications. The target of using this scanner is portal screening of personnel for high-resolution imaging of concealed threat objects. It is not only applied to active terahertz imaging but also applied to passive Terahertz imaging. Terahertz wave can penetrate many materials that are opaque to visible and infrared light, such as plastics, cardboard, textiles and so on. So the terahertz imaging technology has a potential to be applicable in security inspection at airports, stations and other public place. Now, the most terahertz imaging system works at point to point mechanical scan pattern. The speed of this raster scan is too slow to apply in practical field. 2-D terahertz array detector can be applied to real time imaging. But at present their cost is prohibitively high. Fortunately low cost, high performance, opto-mechanically scanner is able to meet the current requirements. An opto-mechanical scanner should be able to rapidly scan a 2-D image of the scene. It also should have high optical efficiency so that an image system can achieve the required thermal sensitivity with the minimum number of receivers. These ensure that it can easily operate at any wavelength, and be active or passive. The opto-mechanically scanning can meets these requirements and is being developed into a high performance, low-cost prototype system that will meet the future needs for terahertz security.

ASON (Automatic Switch Optical Network), which provides fast and dynamic connection from point to point, is the typical representation of the next generation intelligent optical network. There are two main kinds of resource reservation protocols in RSVP-TE (Resource Reservation Protocol-Traffic Engineering), the most widely applied signaling in ASON, which are FRP (forward reservation protocol) and BRP (backward reservation protocol). Both of them are used to apply in single-domain optical network, however, when they are used in multi-domain optical network, there are apparent drawbacks. On base of FRP and BRP, we propose a reservation protocol-IDRPBP, which is based on priority in multi-domain optical network with wavelength converter at border nodes. Through analysis and simulation, we find it can achieve the trade-off between blocking probability and connection setup time.

We introduce a novel approach to interconnect multiple chips together with a silicon photonic WDM point-to-point network enabled by optical proximity communications to act as a single large piece of logical silicon much larger than a single reticle limit. We call this structure a macrochip. This non-blocking network provides all-to-all low-latency connectivity while maximizing bisection bandwidth, making it ideal for multi-core and multi-processor interconnections. We envision bisection bandwidth up to TBps for an 8x8 macrochip design. And a 5-6x improvement in latency can be achieved when compared to a purely electronic implementation. We also observe better overall performance over other optical network architectures.

Most of Micro-fabrication technologies are one complex process. The final machining precision and forming quality of the 3D microstructures are decided not only by the movement and control performance of the machining system, but also by various outside condition factors. Through real-time monitoring the machining process and eliminating the technical error, the fabricating successful rate and completing rate will be improved. In this paper, one process monitoring system based on Machine Vision is presented to be used in one Femtosecond laser micro-fabrication system. According to the technic characteristic, point to point and layer to layer molding, two monitoring strategies are put forwarded respectively to different machining process. Single cell point image is used to judge the laser solidified result through the Support Vector Machine and the machining precision can be promised. The layer image is used to be compared with the design locus and the forming quality of the 3D microstructure can be gained. Whole vision monitoring system is built with the Virtual Instrument development condition, Labview. The image obtaining and process are both realized by software, this decreases the system developing cost. The strategy of the vision monitoring system is also applicable for other micro-fabrication system.

We evaluate a novel method for fully automated rigid registration of 2D manifolds in 3D space based on distance maps, the Gibbs sampler and Iterated Conditional Modes (ICM). The method is tested against the ICP considered as the gold standard for automated rigid registration. Furthermore, the influence of different norms and sampling point densities is evaluated. The performance of the two methods has been evaluated on data consisting of 178 scanned ear impressions taken from the right ear. To quantify the difference of the two methods we calculate the registration cost and the mean point to point distance. T-test for common mean are used to determine the performance of the two methods (supported by a Wilcoxon signed rank test). The performance influence of sampling density, sampling quantity, and norms is analyzed using a similar method.

D-Lightsys considers free space optical links for intermediate communication distances ranging from a few centimeters to one or two meters. In this paper, we present the initial simulations and the first experimental characterizations of a VCSEL-based point-to-point free space interconnect on distances ranging from 16cm to 40cm targeting bit rates up to 2.5Gbps.

A conceptual analysis of contemporary technological approaches for Free Space Optical (FSO) systems is presented, with cost drivers and installation requirements outlined. Major cost and installation drawbacks for typically packaged FSO systems include the number of opto-electronic (OE) interfaces needed to establish a link, rooftop or outdoor power utility requirements, and the mounting structures required to overcome wind loading and system weight. The paper describes an alternative to the traditional approach through the use of fiber coupled transceivers that separate the electronic packages away from the outdoor optical antenna. In this approach, weight and wind loading are minimized, the number of OE interfaces are reduced and special outdoor power utility requirements are eliminated. The fiber-coupled system is inherently low-maintenance and simple to upgrade and provides the low-cost core technology for a metropolitan area network deployment of point-to-multipoint FSO.

Discontinuities and manufacturing flaws affect system performance. The accurate location of flaws and defects is sometimes more important than its precise characterization. For mechanical structures, similarly sized flaws in certain locations are more critical than at other locations. Non- contact microwave inspection systems offer many advantages relative to traditional NDE techniques complex and nonplanar samples as well as composite or anisotropic materials, except where transmission through a metallic object is required. Using spot focused horn antennas, it is possible to detect, locate and identify the inhomogeneities inside dielectric materials with local resolution approaching one wavelength. The system can be completely automated under computer control. Inspection can be done purely in the reflect mode using only one antenna or in the transmission mode using two antennas. The antennas can move on a robotic arm or the system under inspection can move or rotate under the antenna. Surface profiling, shape profiling, and accurate non-contact thickness measurements can be performed in addition to locating flaws and delaminations. Inspection can be done in situ even in high temperature environments since this a non-contact method. Several different examples are presented to illustrate the efficacy of the method as an attractive, user friendly NDE tool.

The point to point telecommunication in the atmosphere with laser signals using the existing optoelectronic technology is an option of the modern communications design. An optical link is strong depending on the optoelectronic hardware parameters and to the topology or to the environment of the applications area. Many laser-links are already fabricated for use in military or in commercial applications. Main advantages are the freedom from licenses, the RFI-EMI immunity, the wide bandwidth and the information security. Main disadvantages are the atmospheric steady and variable attenuation, the radiation hazards and in some cases the material cost. Based on this know-how we describe in this paper the more important broadcasting parameters of radio- TV-teletext programs with laser beams, starting from the atmospheric transmission influence, continuing with a laser selection guide and with some broadcasting electronic techniques and ending with the proposed modification of a coherent laser-link to a new active receiver system which fulfill normal or special laser broadcasting options. Possible applications of our study may be the point to multi-point optical communications for local pay TV, the allocation of optical bands for broadcasting, the radii of cellular laser broadcasting, the simulcasting with laser and RF carriers, the implementations of an interactive Radio and TV, etc.

communication networks [1 ,2]. Like the long haul point to point links these networks are alsoto be optically transparent and their end to end size can be several thousand kilometres. In bothcases optical transparency (that is, the absence of 3R regenerators, usually less than 100kmapart) results in dispersion and non-linear effects accumulating over the entire length of a link.Dispersion shifted (DS) fibres, together with dispersion management schemes, have nowessentially overcome the chromatic dispersion problem. These schemes can also keep thepenalties due to non-linear effects to within acceptable limits [3]. However, polarisation modedispersion (PMD) still remains as a significant and now the main dispersion mechanism whichlimits the maximum attainable bit rate times distance product for these links. This limitationdue to PMD applies not just to the new generation of links and networks using DS fibre. Theyalso apply, again as a highly significant limitation now, to upgrading the transmission bit rate

The communication overhead in many multiprocessor computing platform is a critical factor over performance. In this paper we present communication performance of a large processing array built with TI 320C40 DSPs. Inter-processor communication is provided by message passing which is a common method used in multiprocessors systems. The system is developed for image processing therefore transmission of large data blocks and various forms of communication are required frequently. The processor used in this system has six built in communication links. They are 8-bit, bi-directional links with a speed of 20 Mbytes/sec. A processing array built with these processors employs MIMD paradigm and static interconnection. In this paper, the communication performance of such DSP network is investigated and performance results are presented. The communication functions include broadcasting, scattering, gathering and point to point transmission of messages.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Smart Skin Array Technology is a technology that has been developed and patented by PageAutomated Telecommunications Systems, Inc. It is based on a new fabrication methodologywhich allows highly dense fiber optic parallel pathways to be manufactured in a repeatablemanner with up to 100 fiber optics per inch, in widths of up to 12 feet and long lengthsmany meters > 500, the anticipation is with correct adjustment > 1000 meters. The technology allows for customization of fiber type, spacing between fibers and density fromone upward. The ability to control spacing between fibers enables the base material tointerface with various types of optoelectronic arrays and in diverse interconnect scenarios.Such a capability lends itself to be a repeatable and controllable, point to point,optoelectronic interface. In such a highly parallel system, performance need not bedegraded. In this paper, we will describe some of those attributes which provide for thebenefits achievable with this technology. It is these benefits which will provide for viableFly by Light systems. The flash program will incorporate these in the development of thephysical cable plant.1. SMART SKIN ARRAY TECHNOLOGYWe have fabricated a woven material in which optical fibers are positioned and held in thecomposite material in a manner to maximize optical efficiency. The woven grid-like mat ismanufactured using conventional equipment which positions both the optical fibers and thecomposite fibers. This robust material can then be coated with a further protective material,i.e. an elastomer which enables it to form a flexible sheet or it can be laminated or epoxyencased for rigid structures. This material can be used to provide sensing, imaging,communications. It can be utilized for optical backplanes, for optical cabling, ribbons,interconnect in optoelectronic systems. It can be housed in facilities, i.e. in walls, conduits,under rugs, car doors, in aircraft structures, etc. Due to its flexible protection material, itcan be molded to fit in hard-to-get places

The Digital Imaging and Communications in Medicine (DICOM) 3.0 Standard is a multi-part document which defines point to point and network-based communication. The standard is modular in design to allow individual parts to change independently and to allow new parts to be added as needed. Part 8 of the standard specifies how DICOM applications can be layered on top of an Upper Layer Protocol defined for TCP/IP or on top of ISO network profiles.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The American College of Radiology (ACR) and the National Electrical Manufacturers Association (NEMA) are defining the Digital Imaging and Communications in Medicine (DICOM) V3.0 Standard. Previous authors have investigated the performance of the ACR- NEMA V1.0 and V2.0 Standards in point to point and network applications. This paper describes an early implementation of a subset of the DICOM V3.0 Standard and presents performance results for a combination of workstation types and network technologies.

Historically, image quality issues involved with matching the `look' of an image on a modality monitor, such as CT, MRI, or Ultrasound, with the `look' at either a remote viewing station or on printed film could be dealt with by adjusting the individual components on an ad hoc basis. As medical imaging moves away from point to point connections and into a networked environment, a standard is needed that insures image integrity with respect to tonescale and guarantees that the look of the image at various imaging systems and printers can match the original modality monitor look. A standard way of describing image presentation using look- up tables is proposed. This provides a `standard' network that each manufacturer can connect to and provides consistent image quality with respect to tonescale. This method expands upon the current ACR-NEMA implementation, which already provides some information that allows for consistent image presentation.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Future communications networks will be required to provide the switching of very broad-band digita'' channels (typically 155. 52 Mb/s or higher) for as many as 60 customers. Power consumption and cable management are a major factor in the systems level design considerations. It is shown that through the use of ultra-low threshold laser diode arrays optical fiber ribbon cables and a thoughtful packaging strategy significant electrical power advantage can be accrued over conventional electrical interconnection approaches. 1_a© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A 'many points in one point' multiaccess laser system has been examined, and results are reported which indicating the feasibility of optical communications multiaccess communications is feasible and that the resultant terminal size and with savings are very substantial compared to the dedicated optical terminals or RF multiaccess approaches. A preliminary design has been accomplished of a package that can weigh less than 150 pounds and which uses a 10-in. effective diameter fixed telescope and requires less than 100 W of regulated power and less than 8 cu ft of space.

Fiber optic networks in the telecommunications and Local Area Network (LAN) applications are typically active networks (point to point fiber optic links interconnected using active devices). Short distance automotive networks have a sufficient flux budget to allow passive optical distribution. This paper reviews the differences between Telecommunications, LAN, and automotive network applications. The benefits of a passive star architecture will be described and a passive star implementation, based on large diameter plastic fibers, will be described.

The benefits of fiber optics for telecommunications and Local Area Networks (LANs) are well documented. The benefits to passenger car applications are not as clearly defined. This paper examines the differences between Telecommunications, LAN, and automotive point to point and network applications. Current production automotive applications of optics and fiber optics, automotive data communications trends, and both functional and non-functional requirements and constraints will be described.

Fibre optic technology is now being exploited in many diverse applications including long haul and local network communications, using both direct detection and coherent techniques, sensor systems, microwave optical links and for signal processing. These applications demand active optoelectronic terminal devices such as sources, detectors and integrated components with performance parameters suitable for the application as well as costs (or cost projections) low enough to catalyse the development of the systems. Single frequency distributed feedback (DFB) lasers are now becoming widely available and are suitable for high speed (>2Gb/s) direct detection and for FSK cohefent systems. DFB lasers in combination with external or integrated passive cavities offer reduced linewidth and rapid electronic tuning, opening the way to multichannel subscriber networks. Optoelectronic components capable of microwave bandwidths (10-30 GHz) are also being reported; such components will find applications in microwave bandwidth point to point links, radar remoting and optical signal processing. Critical components here include the laser source, which may be directly modulated or followed by a high speed guided wave modulator and the detector/receiver. In this presentation developments in such active components for single mode fibre systems were reviewed.