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We report on progress at the Northrop Grumman Aerospace Systems (NGAS) starshade testbed. The starshade testbed is a 42.8 m, vacuum chamber designed to replicate the Fresnel number of an equivalent full-scale starshade mission, namely the flagship New Worlds Observer (NWO) configuration. Subscale starshades manufactured by the NGAS foundry have shown 10 -7 starlight suppression at an equivalent full-mission inner working angle of 85 milliarseconds. In this paper, we present an overview of the experimental set up, scaling relationships to an equivalent full-scale mission, and preliminary results from the testbed. We also discuss potential limitations of the current generation of starshades and improvements for the future.

Fluorescent proteins are the most common and versatile class of genetically encoded optical probes. While structure-guided rational design and directed evolution approaches have largely overcome early problems such as oligomerization, poor folding at physiological temperatures, and availability of wavelengths suitable for multi-color imaging, nearly all fluorescent proteins have yet to be fully optimized. We have developed novel methods for evaluating the current generation of fluorescent proteins and improving their remaining suboptimal properties. Little is yet known about the mechanisms responsible for photobleaching of fluorescent proteins, and inadequate photostability is a chief complaint among end users. In order to compare the performance of fluorescent proteins across the visual spectrum, we have standardized a method used to measure photostability in live cells under both widefield and confocal laser illumination. This method has allowed us to evaluate a large number of commonly used fluorescent proteins, and has uncovered surprisingly complex and unpredictable behaviors in many of these proteins. We have also developed novel methods for selecting explicitly for high photostability during the directed evolution process, leading to the development of highly improved monomeric orange and red fluorescent proteins. These proteins, most notably our photostable derivative of TagRFP, have remarkably high photostability and have proven useful as fusion tags for long-term imaging. Our methods should be applicable to any of the large number of fluorescent proteins still in need of improved photostability.

Effects-based operations (EBO) are proving to be a vital part of current concepts of operations in military missions and consequently need to be an integral part of current generation wargames. EBO focuses on the producing effects from military activities, as opposed to the direct result of attacking targets. Alternatively, the emphasis of conventional wargames is focused on attrition-based modeling and is incapable of assessing effects and their contribution to the overall mission objectives. For wargames to be effective, they must allow users to evaluate multiple ways to accomplish the same goal with a combination of direct, indirect and cascading events (actions). The focus of this paper is to describe the development of a methodology for the implementation of EBO concepts into modern wargames. The design approach was to develop a generic methodology and demonstrate how simulation objects can incorporate EBO capabilities. The authors will illustrate the application of the methodology utilizing an EBO scenario example, which was developed to test the system.

The challenge of delivering acceptable semiconductor products to customers in timely fashion becomes more difficult as design complexity increases. The requirements of current generation designs tax OPC engineers greater than ever before since the readiness of high-quality OPC models can delay new process qualifications or lead to respins, which add to the upward-spiraling costs of new reticle sets, extend time-to-market, and disappoint customers. In their efforts to extend the printability of new designs, OPC engineers generally focus on the data-to-wafer path, ignoring data-to-mask effects almost entirely. However, it is unknown whether reticle makers' disparate processes truly yield comparable reticles, even with identical tools. This approach raises the question of whether a single OPC model is applicable to all reticle vendors. LSI Logic has developed a methodology for quantifying vendor-to-vendor reticle manufacturing differences and adapting OPC models for use at several reticle vendors. This approach allows LSI Logic to easily adapt existing OPC models for use with several reticle vendors and obviates the generation of unnecessary models, allowing OPC engineers to focus their efforts on the most critical layers.

This paper examines the Navy's current electro-optical systems involved in mine countermeasures to establish a baseline for critical environmental parameters which affect their performance. Having established this baseline of system-related parameters, we examine the current generation of environmental measuring capabilities to determine what further developments are needed to cover the shortfall in capability. A suite of measurements is then proposed, which will allow the Navy a performance-predictive capability to assess the expected operation of the sensors.

The ever-increasing demand on circuit performance necessitates rapid deployment of optical lithographic as well as early production next generation lithographic tools. Successful execution of the multitude of development programs involved requires careful consideration and implementation of system architecture with special emphasis on program synergy and modularity. This paper presents performance data and system budgeting and allocation for current generation lithographic tools, and building from that basis, discusses evolutionary approaches for critical performance areas and modules. Supporting analytical results regarding performance of these modules are also discussed.

Every new generation of fighter aircraft presents new challenges for the various design disciplines that are involved in their development; the current generation of fighters — Eurofighter, Rafale, and F22 — are no different in this respect. We look to using new structural material, advanced flight control systems, and ever better and more comprehensive sensors to extend the system's overall performance and capability. This paper looks at the area of cockpit design — the “how de we keep the pilot in real control of his tasks” part of the total package of the aircraft and weapons system desing.

With the current generation of x-ray astronomy observatories either in orbit (ASCA, ROSAT) or well on the road to completion (Spectrum-X(gamma) , XMM, AXAF), plans are being developed for what is being classed as the next generation of x-ray observatories for launch by the space agencies of Europe, USA and Japan. In all of these mission concepts, together with many smaller mission concepts, the charge coupled device (CCD) is seen as playing a key detector role, building upon its successful use in current missions where it is used for both dispersive, and imaging, x-ray spectroscopy applications. This paper reviews the goals of the concept observatories and discusses near-term CCD developments which are needed to meet the future instrument requirements. In addition, since future observatories will have larger collecting areas, a concept design is proposed for a high throughput x-ray imaging/spectroscopy camera as a progression beyond that of the EPIC MOS camera on XMM.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Real-time infrared (IR) scene generation from HardWare-in- the-Loop (HWIL) testing of IR seeker systems is a complex problem due to the required frame rates and image fidelity. High frame rates are required for current generation seeker systems to perform designation, discrimination, identification, tracking, and aimpoint selection tasks. Computational requirements for IR signature phenomenology and sensor effects have been difficult to perform in real- time to support HWIL testing. Commercial scene generation hardware is rapidly improving and is becoming a viable solution for HWIL testing activities being conducted at the Kinetic Kill Vehicle Hardware-in-the-Loop Simulator facility at Eglin AFB, Florida. This paper presents computational techniques performed to overcome IR scene rendering errors incurred with commercially available hardware and software for real-time scene generation in support of HWIL testing. These techniques provide an acceptable solution to real-time IR scene generation that strikes a balance between physical accuracy and image framing rates. The results of these techniques are investigated as they pertain to rendering accuracy and speed for target objects which begin as a point source during acquisition and develop into an extended source representation during aimpoint selection.

The tremendous growth in the building of large 8 m and 10 m telescopes, which give substantial gains in sensitivity over the current 4 m telescopes, presents a significant challenge to the builder of a future 21st Centrum groundbased telescope. To try and explore the possible scientific motivations that may drive a future groundbased facility, I have chosen a current observational project whose completion is beyond the capabilities of our new generation of telescopes. By examining what is required of a groundbased facility to undertake spectroscopy on the majority of the objects in the Hubble deep field (HDF), it becomes apparent this project will need a very large imaging infrared array (VLIA) or a 50 m telescope. The main conclusion of this comparison is that any groundbased facility capable of undertaking this project is likely to cost at least one billion dollars. The choice between the two differing approaches should therefore be driven by the scientific aspirations of the 21st century community of astronomers. Superficially, the 'scientific edge' probably belongs to the VLIA facility, with its ability to probe structures at infrared wavelengths down to the milli-arcsecond scale. The more profound issue is whether it is time for groundbased astronomers to begin looking to space for the placement of their next 21st Century telescope.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Exploiting instrument platforms like the current generation of 8 - 10 m class telescopes represents a new era in instrument design, construction, handling, and use. Gemini's instruments are no exception to this revolution. For example, since at least 50% of Gemini's observing time will be queue scheduled, Cassegrain-mounted instruments will effectively remain on- line, ready to be called into service for typically months at a time with minimal delay to match observing programs with changing conditions. Furthermore, effective instrument emissivities of less than 1% will be needed to take advantage of the very low emissivity of the telescopes. Here we report on the technical status of the phase I instruments, describe attention being given to the total system performance of the telescopes and instruments, and list some of the considerations going into the phase II instrument program.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Hard x-ray (> 10 keV) concentrators are of key importance to overcome the sensitivity limitations of the current generation of (imaging and non imaging) direct viewing telescopes for hard x-ray astronomy. We studied the feasibility of a hard (> 10 keV) x-ray concentrator based on the Bragg diffraction technique. Apart from its unprecedented sensitivity in the band from 10 to approximately 100 keV, this concentrator has an intrinsic capability to measure the polarization of x rays in the low energy part of its operative range. In this report we discuss this property and the expected sensitivity of the instrument as a polarimeter.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Automatic alignment has been offered by most manufacturers of alignment tools in recent years, and is regarded as essential in acheiving the overlay accuracy required to produce the current generation of fine-line integrated circuits. However, problems associated with the automatic alignment technologies themselves can offset the gains achieved and can, in worst case, actually degrade overall registration performance. Two important problems which must be overcome are: Autoalignment offsets which can cause alignment accuracy to deviate by more than a micron, even though precision is quarter micron or better. 2. Process-dependent variations- causing changes in the topographical and optical characteristics of the alignment keys which can change or degrade the signal produced by the key.

Laser beam directors have grown from centimeter size to near two meters in the last 20 years. As the size increased, they began to adopt the appearance of large astronomical telescopes, while retaining the operational features of high speed tracking mounts. This paper describes the current generation of beam directors and discusses design requirements for larger mounts.