The Hobby-Eberly Telescope uses a 11-meter diameter F/1.45 segmented spherical primary mirror. A spherical mirror of this size generates large amounts of spherical aberration. To be used successfully in a tilted optical Arecibo type telescope, the spherical aberration needs to be corrected. This means that tracking of astronomical targets is achieved through moving a tracker optical package which imposes somewhat severe packaging constraints. Given these packaging constraints, novel methods must be employed to correct the aberrations with the Spherical Aberration COrrector contained in the moving tracker optical package. The paper reviews the pertinent requirements, constraints and the resultant design of the Hobby-Eberly Telescope Four Mirror Spherical Aberration Corrector.

The Next Generation Sky Survey Telescope is a spaceborne cryogenic optical telescope with four channels covering the wavelength range 3.5 to 23 microns. The 0.5 m aperture telescope is based on a modified three mirror afocal design, with a scan mirror at the exit pupil compensating for the spacecraft motion. After the scan mirror, the light is spectrally split and focused by three refractive camera systems onto four detector arrays. The nominal optical design exceeds the requirement of diffraction limited performance at 8 microns wavelength over the 1 degree by 0.5 degree field of regard.

The QuickBird telescope represents a significant accomplishment as the first large-aperture, high-resolution, totally unobscured optical system developed as a fixed-price commercial product. The telescope was aligned and tested in a dedicated facility at Ball Aerospace and Technologies Corp. specially developed to reduce the total process time of building and testing complex optical systems. This presentation summarizes design features, mirror- manufacturing results, telescope alignment, and test results.

The Laser Interferometry Space Antenna for the detection of Gravitational Waves is a very long baseline interferometer that will measure the changes in the distance of a five million kilometer arm to pico meter accuracies. Knowledge of the phase deviations from a spherical wave and what causes these deviations are needed considerations in the design of the telescope and in determining pointing requirements. Here we present the far field phase deviations from a spherical wave for given Zernike aberrations and obscurations of the exit pupil.

We describe the features of the optical system for Terrestrial Planet Finder, a space-based, cryogenic interferometer for direct detection of Earth-type planets around nearby stars. Destructive interference in a stellar interferometer suppresses stellar glare by a factor of several thousand or more, and phase chopping distinguishes planet light from symmetric backgrounds. The mid-IR is favorable for detecting planetary emission relative to that from the star, and this spectral region also offers important molecular signatures indicative of key atmospheric gases.

This paper describes the design of a camera system capable of acquiring stars during both the day and night cycles of a high altitude balloon flight. The camera system will be filtered to operate in the R and I bands, and simulations have been run using MODTRAN atmospheric code to determine the worse case sky brightness at 35k. With a worse case daytime sky brightness of 2 X 10^-5/sr/micrometers at 600nm, the sensitivity of the camera system will allow acquisition of at least 1-2 stars/degrees² at star magnitude limits of 7.8-8.1. The system will have an F2.8, 64.3mm diameter lens and a 1340 X 1037 CCD digitized to 12 bits. The CCD is comprised of 6.8micrometers X 6.8micrometers pixels with a well depth of 45,000 electrons and quantum efficiency of 0.54 at 700nm. The camera's field-of-view will be 6.33 degrees² and provide attitude knowledge to 8 arcsec or better. A test flight of the system is scheduled for fall 1999.

We describe the theoretical design and experimental fabrication of high power 0.98 micrometers strained quantum well lasers employing broad waveguide structure and novel hybrid material system of Al-free InGaAs/InGaAsP active region and AlGaAs cladding layers. The use of AlGaAs cladding, instead of InGaP, provides advantages in flexibility of laser structure design, simple epitaxial growth, improvement of surface morphology and laser performance. In addition to the theoretical study of the new structure, we successfully demonstrate the design by obtaining high performance laser devices. The as-grown InGaAs/InGaAsP/AlGaAs laser material exhibits very high quality with low threshold current density of 200 A/cm², high internal quantum efficiency of approximately 93 percent, and low internal loss of 1.2 cm^-1. For 100 micrometers -wide stripe lasers with cavity length of 800 micrometers , a high slope efficiency of 1.03 W/A, low vertical beam divergence of 36 degrees, high output power of 3.65 W, and very high characteristic temperature coefficient of 250 K are achieved.

We report new observations of optical spatio-temporal structures formed in a naturally isotropic solid-state material. The phenomenon is due to laser-induced anisotropy. In fact, a part of the optical power is absorbed by the material which leads to the sample heating,the refractive index of the medium becomes laser power dependent under strong beam intensity excitation. This refractive index variation modifies in turn the optical polarization of the beam. As a consequence of polarization pattern is induced. If the material is placed near the laser beam focus, usually the induced depolarization is strong due to the high beam intensity. We observed however, that the induced depolarization is reduced sharply near the focus. This phenomenon was not observed up to now. We have developed a model which shows that both the index variations in transverse and longitudinal directions contribute to the phase shift, and are responsible for the depolarization. As a result, the competition between these two contributions plays a key role in the polarization changes near focus. Our observation is accounted for by a transient nonlinear refractive index model. Good agreement with the theoretical description of the pattern formation is obtained. We found that in some appropriated experimental configurations, these spatio-temporal structures present advantages in the applications, e.g. in conceiving a 2D vectorial optical sensor.

Laser encoders overcome the fundamental resolution limit of geometrical optical encoders by cleverly converting the diffraction limit to phase coded information so as to facilitate nanometer displacement measurement. As positioning information was coded within the optical wavefront of laser encoders, interferometry principles thus must be adopted within the design of the laser encoders. This effect has posed a very strong alignment tolerance among various components of the whole laser encoder, which in turn impose a serious user adaptation bottleneck. Out of all alignment tolerance, the head-to-scale alignment tolerance represents the most important hindrance for wider applications. Improving the IBM laser optical encoder design by taking into the consideration of manufacturing tolerance of various optical components, an innovative linear laser encoder with very high head-to-scale tolerance is presented in this article. Efficiency of the TE/TM incident light beams on the grating scale used are examined theoretically and verified experimentally so as to provide design optimizations of the grating scale. Effect of various grating scale, quartz master or polymer-based grating replicate, is also detailed. Signal processing used to decoded the quadrature based positioning optical signal is also studied. Experimental results that verify the resolutions of the tabletop laser encoder prototype by comparing the decoded quadrature signal and a HP laser interferometer output signal is also presented.

A 2D FDTD analysis of a microcavity distributed Bragg reflector (DBR) surface emitting laser (SEL) is carried out in this paper. The reflectivity of the DBR, mode structure and light output versus pumping current curve of the microcavity DBR SEL are calculated and presented.

In this work, modeling along with associate experiments of the broad-area laser with an external optical cavity which employs a mode-selecting mirror has been conducted to study the effects of optical feedback on the filamentation and mode control of broad-area semiconductor lasers. By using split-step FFT algorithm in a propagation mode, mode profiles of the broad-area lasers with a spherical cavity are simulated in detail, the simulation results agree very well with experimental measurements and verify the validity of the simulation model. Mode control of broad-area semiconductor lasers has also been studies through employing the same simulation model and associates experiments have also been conducted. The results will be presented in this paper.

Injection control of pulsed laser has been studied with polarization seeding in a copper vapor laser chain by ways of numerical simulation and experiment. The control effect of the injection signal is detected by measuring the output laser beam's polarization degree. Related parameters as pulse width, delay time and output beam's polarization degree stability are considered.

TO utilize the mother lines to be perpendicular to each other in front and rear groups of cylindrical lenses, diffusing beam 44 degrees X 13 degrees from the window of semiconductor laser are compressed as 'parallel rays' to emerge into +/- 0.0025 rad. The sizes of the laser window are 0.1285 mm X 3.239 mm. The front focal points of cylindrical lenses in two groups are superimposed on the center of the window, and its types of second surfaces are hyperbolic and oval.

Steward Observatory is completing the manufacture of a deformable f/15 secondary mirror for the 6.5m Multiple Mirror Telescope conversion that will, along with the wavefront sensing system, compensate for atmospheric turbulence. A potential difficulty of an adaptive secondary mirror is the ability to verify the commanded mirror shapes of a large convex deformable surface. An optical design is presently being implemented to test the deformable mirror's closed loop control system by optically projecting an artificial star to simulate starlight in the actual telescope. The test system has been designed to verify the control system by fitting into both a laboratory test structure as well as the telescope support structure itself. The optical design relies on two wavelength computer generated holograms used to remove spherical aberration as well as aid in the alignment of the test system optics by projecting alignment patterns.

Recent developments in the field of high transmitting beam shaping optics for material processing are presented. Central parts of these optics are non-rotationally symmetric optical elements (NOEs). Advanced design principles for NOEs are presented. An optical setup containing a NOE and a system for the adaptation of the spatial coherence properties of excimer lasers to the processing requirements are presented together with beam diagnosis and material processing results. In comparison to results obtained earlier a largely increased beam shaping performance is demonstrated.

The dual use, signaling and communication, of LED traffic signal system is described and analyzed. The primary function of a traffic light system is to give traffic and pedestrian signals. A prototype of LED traffic signal head is developed to perform a secondary function: communication. A wireless communication link is set up using the LED traffic signal head as the transmitter. The LEDs are modulated to transmit information-carrying light. The receiver uses a silicon photodiode to detect the transmitted radiation. Using visible light as the transmission medium, a 1 Mbit/s wireless data link is obtained.

This paper gives a brief introduction into the background, application, and design of Wavefront Coding imaging systems. Wavefront Coding is a general technique of using generalized aspheric optics and digital signal processing to greatly increase the performance and/or reduce the cost of imaging systems. The type of aspheric optics employed results in optical imaging characteristics that are very insensitive to misfocus related aberrations. A sharp and clear image is not directly produced from the optics, however, digital signal processing applied to the sampled image produces a sharp and clear final image that is also insensitive to misfocus related aberrations. This paper gives an overview of Wavefront Coding and example images related to the two applications of machine vision/label reading and biometric imaging. Design techniques of Wavefront Coding are unique from that of traditional imaging system design since both the optics and digital processing characteristics of the system are jointly optimized for optimum system performance.

The design of a wide field-of-view head-mounted display (HMD) is very challenging. Unfortunately, traditional design methods produce low-resolution imagery that is unacceptable for some tasks. One method of addressing this challenge is to optically tile several smaller field-of-view displays to form a single, wide field-of-view, high-resolution image. This paper will address design issues specific to optically tiled system including otpical performance, seam placement and binocular rivalry.

This paper presents the results given by the nominal design and tolerance analysis of a narrow-field-of-view camera lens equipped with a rotating prism scanning system. The first aspects taken into consideration have been the compensation of the chromatic aberration, distortion reduction, and the correlation between depth-of-field and lens resolution. Then, a rigorous approach to determine the relationship between the field-of-regard direction and the prism orientations is discussed. Finally, the tolerance analysis results give the predictable pointing direction precision as function of the system tolerances.

The double expansion of the wavefront deformation in Zernike polynomials over the pupil and the field-of-view coordinates is a powerful tool for lens design, testing, and alignment. It provides a compact description of the wavefront deformation of perturbed and unobscured optical systems over the field-of-view. The integral of the mean-square wavefront deformation over the field-of-view is simply the sum of the products of the norms of the polynomials and the squared global coefficients. Eight or ten global coefficients can provide a comprehensive centered system description. Only fourteen main additional global coefficients is sufficient for the description of perturbed and unobscured optical systems.

Abstract not available.

Bi-AGRIN cemented doublets, super corrected for zero axial color, spherical aberration and sphero-chromatism can show polychromatic performance in the range of 0.004 waves PV or better at the red and blue wavelengths for speeds up to F/2. These doublets are comprised of two elements of axial gradient index glass. The crown and flint elements are each designed with separate and distinct gradient glass lines, giving each element an axial gradient in refractive index and dispersion. This paper examines one design and its performance sensitivity to dispersion modeling via the Buchdahl and Sellmeier dispersion equations.

A number of optical plastic materials are examined. The indices of refraction are measured in the visible and near- IR spectral regions from 435.8 nm to 1052 nm. Some obtained data and Abbe constants are presented. The glass libraries of the optical design software packages are updated. The spherochromatic aberration balancing is analyzed during the all-plastic doublet and triplet synthesis for a working wavelengths interval from 600 nm to 900 nm. Two achromatic triplets are designed intended for NIR region. Three all- plastic 3X magnifiers are developed for NV goggles. The optical configurations are given. The aberration corrections are evaluated. The obtained optical performance is illustrated. Some conclusions for the trends in all-plastic optical design are drawn.

We have examined the main constraints on the design of single-channel, high-capacity soliton communication systems. In the average soliton regime, the Gordon-Haus timing jitter limits the bit rate to less than 7 Gb/s for transoceanic fiber links, while for shorter transmission distances the main limitation is fiber perturbations arising from discrete in-line amplification. The use of dispersion-decreasing fibers and of periodic optical phase conjugation for jitter control can increase significantly the capacity of soliton communication systems. We found that the third-order dispersion assumes a prominent role in this case. Reducing this effect sufficiently, the main constraint becomes the soliton-soliton interactions and bit rates superior to 110 Gb/s can be achieved for amplifier spacings less than 80 km. For higher amplifier spacings the bit rate is limited by the Raman induced timing jitter.

In the use of ball bearings as retro-reflectors for testing optical systems in a double pass configurations, care must be taken when choosing the radius of the ball bearing. Using too small a radius can adversely effect the wavefront error as presented by the interferometer. The wavefront error, being a function of wavelength, can be significantly altered due to this ball bearing error, particularly in long wavelength IR systems tested with a visible light interferometer. This paper is the result of research towards understanding and modeling this error in the presence of spherical aberration.

We present the design of a compact, low-cost finger imager, to be used for enrolling and recognizing individuals based upon their finger ridge patterns. The optical system employs viewing beyond the critical angle and darkfield illumination for maximum image contrast. The optical system is afocal and telecentric, achieving corrected distortion with oblique viewing.

Modern CCD cameras that are typically produced in high volume for consumer and machine vision applications can be used as precisely calibrated image sensors. New CCD chips with on-chip micro lens arrays, however, have some characteristics that limit design choices where precise illumination uniformity is required. The micro lenses cause vignetting and limit the angular aperture of each pixel. This paper measures vignetting and consequent shading for a typical micro lensed CCD chip. Nevertheless, when properly designed, camera system employed these advanced CCd chips can be precisely calibrated with respect to face plate irradiance.

The international DVD standard, ECMA-267, for compact discs with improved storage capacity is based on a semi- transmitting mirror. This coating provides a top memory layer that permits reading an opaque second mirror layer underneath. According to the standard, the top layer should have a reflectance in the interval 18-30 percent and simultaneously sufficient transmittance to permit a reflectance in the same interval from the bottom mirror layer, all at the reading wavelength 650 nm. The standard also includes the optical effects of the 550 micrometers polycarbonate disc and the 55 micrometers spacer layer used for protection.

Some results obtained in the realization of compact relay system design are presented. Four optical configurations have been analyzed. Two symmetrical schemes were examined having field Smith's lenses for an image scaling of -1x. The achieved numerical aperture is up to 0.35 and the MTFs curves are at 40 cycles1/mm for a contrast ratio of 0.2. The third design has a large field of 40 mm but its F-number is about F/4.5. The last relay system is unsymmetrical. The scaling is 2x and the image field exceeds 50 mm. The aberration balancing result and the optical systems performance are illustrated.

Steward Observatory is building a deformable f/15 secondary mirror that will compensate for atmospheric turbulence for the 6.5m Multiple Mirror Telescope conversion. With the proposed adaptive optics system, this new telescope is expected to resolve diffraction limited images, approximately an order of magnitude better than present seeing. This improved visibility with a larger light collecting area and low thermal background requires a new science instrument, diffraction limited for the 1 to 5 micrometers region. This science instrument, presently in its early manufacturing stages, consists of four cameras, low resolution spectroscopy with grisms, high resolution spectroscopy with a cross-dispersed Echelle grating and an atmospheric dispersion corrector. The cameras will provide simultaneous slit viewing, differential imaging and two pixel sampling over the full wavelength band. Each camera will operate with a 1024 X 1024 HgCdTe array optimized for the spectral region of the camera. An IR tip/tilt sensor is also incorporated into the instrument that will relay natural guide star motion to the adaptive secondary in a closed-loop approach. This paper is an optical design instrument overview.

DNA-based fluorescent microarrays are fast becoming the preferred tool for studying a variety of complex biochemical phenomena ranging from multiplex mutation detection, to gene mapping and expression monitoring, and high throughput screening for new drug candidates. Fluorescence is a low energy phenomenon. The need for rapid, high resolution, wide field imaging of fluorescent microarrays calls for a specialized microscope architecture. We now describe the design of a 'Flying Objective' epi-fluorescence microscope that is ideally suited to this application, and compare the performance of this novel instrument with two other commercial epi-fluorescence microscopes designed to read DNA microarrays.

The double monochromator is a system of two single monochromators, in which the exit slit of the first monochromator is the entrance slit of the second one. We can use the double monochromator if we want to decrease the scattering light level or increase the dispersion of the spectral device. In the adding dispersion double monochromator all aberrations add. The traditional way of optimization of the double monochromator parameters is the two concave diffraction gratings, in which the second single monochromator particularly compensates the defocusing, the meridional coma and the first order astigmatism of the first one. Calculation of this monochromator have been done using numerical methods. More compete optimization of the optical mounting of spectroscopic device consists of two diffraction gratings can be done using light path function consideration. Geometric theory of two - steps recorded grating have been developed for holographic gratings recording. In this paper this theory is expanded for the case of double monochromator. The developed theory gives possibility for more complete aberration compensation, which allows to increase the spectral and the spatial resolution as well. Improvement of spectral and the spatial resolution is actual for different types of spectroscopic deices, for example, for the plasma diagnostic spectrometers.

Experiments such as CHORUS at CERN require the inspection of a large amount of nuclear emulsion plates exposed to particle beams. Rare events need to be found, measured and analyzed. Their features are stored as grains in microscopic dimensions in a 3D stack of plates. A new, fully automatic immersion microscope system was developed for this purpose. It features high resolution, small depth of focus, large working distance, large field of view and synchronization of illumination and detector. An additional requirement is given by variations in the refraction index and in the relative thickness of immersion oil and emulsion. The approach used here is an imaging system based on a various objective lens with extreme numerical aperture, large working distance and wide field, combined with a matched high-aperture Koehler illuminator. The light source is a mercury arc lamp, combined with a filter package for the g- line. It includes liquid crystal elements for synchronized shuttering and variable attenuation. The theoretical resolution is less than 1 micron in x, y, z within a volume of 0.5mm diameter times 1 mm scanning depth in all situations within a predefined index range. Three identical pieces of the system have been built. The identical pieces of the system have been built. The experimentally measured resolution confirms the expectations and is better than 1 micron in all three dimensions. This is the result of a complex process of system design and manufacturing, unifying optical, opto-mechanical and opto-electronical contributions. This process spans from the early stages of feasibility and manufacturing up to the test and adjustment procedures. The three prototypes are operational since the fall of 1998 in the frame of the CHORUS project. Practical experience and application results are presented.

Volume phase (VP) gratings are now available and being applied to the applications of astronomical spectroscopy, Raman spectroscopy, ultrafast lasers, and wavelength division multiplexers. A volume phase grating results from the recording of an interferometric pattern within the volume of a material which, when suitably processed, becomes a modulation of the material's index of refraction. When a VP grating is substantially illuminated, the light interacts with the material due tot he recorded pattern. Light propagates within and out of the VP grating according to Bragg diffraction. Definitions of various VP gratings designed and fabricated to study performance are provided as relating to the applications listed above. Performance parameters include diffraction efficiency, spectral coverage, and angular coverage. Descriptions of the test methods are given. Performance data is provided and compared to the respective design.

We have designed a new kind of 3D image capture system based on a new 3D ring lens. In this paper we represent a calibration procedure for this kind of system using the information from the surrounding environment. It is mainly based on motion in one direction with known value and establishing the correspondence between the successive views to derive system parameters. The main differences between calibration of the traditional stereo system and the new one are also discussed.

Correlation between computational models and corresponding experimental data of stray light produced by unwanted diffraction orders of diffractive lenses is described. It is shown that the attractive scalar model under Fresnel approximation does not agree with experimental data. The validity of Fresnel approximation for multi-order focusing optics is derived to ex[plain the limitation of the scalar approach. Geometrical models with both coherent and incoherent summation of each diffraction orders coupled with efficiency estimation is used with success. The model takes into account the local diffraction efficiency and also of the number of diffraction orders supported locally by the structure. This geometrical optics model can be used in standard optical design software. Therefore it may be recommended as an additional tool for stray light analysis at the design stage of hybrid refractive/diffractive optical systems. In a second part, the impact of unwanted diffraction orders when diffractive optics is used in visible imaging system is discussed. Several experimental observations about the use of plastic/diffractive lens in relation to different fabrication process used to build the lens are also discussed. From those observations, we recommend an approach to reduce the stray light produced by the diffractive lens. In conclusion, a serious stray light analysis is mandatory in the design of visible imaging systems using diffractive lenses.

Veiling glare occurs in an imaging system when non-image forming flux strikes the focal surface. This light tends to reduce image contrast and can be caused by surface defects, dust, or anything else that might cause light to deviate from its intended imaging path. Fresnel lenses contain many such non-image forming structures as a result of their faceted and discontinuous nature. Sample optical systems for an extensive air shower observatory have been designed that consist of multiple Fresnel lenses. Veiling glare is expected to be significant in these systems, and it is desired to quantify its extent and ramifications. To this end, a series of test has been performed on the Fresnel lens systems using non-imaging optical analysis software . A method for obtaining veiling glare information efficiently has been developed based upon the manner in which it is measured in real optical systems. By using computer software, the effects that several different parameters have on the veiling glare are analyzed independently without the use of expensive prototypes. It is shown that the amount of veiling glare is highly dependent upon the system configuration and that generalized conclusions regarding veiling glare and the number of Fresnel surface sin a system are not possible. The analysis methods developed here, however, can be used to efficiently analyze the stray light in any system.

Ball Aerospace is building the Cryogenic Telescope Assembly (CTA) for the Space IR Telescope Facility (SIRTF) project and stray light control is a critical part of this effort. The heliocentric orbit where the Sun is never allowed to illuminate the CTA and the Earth is relatively far away is a key feature for stray light control. Mirror and paint BRDFs were measured at various SIRTF wavelength sin order to provide inputs for the stray light models. Stray light from telescope self emission, a distant point source, and the galaxy were analyzed. The design ensures that stray light will be less than 21 percent of the celestial background at all SIRTF wavelengths.

Many illumination situations involve a flat surface and an oblique luminaire placement. Today's commercially available luminaires give very uneven illumination here. A novel injection-moldable segmented lens is presented that will uniformly illuminate a rectangular zone, such as a stair- step or a picture on a wall. Its design is a development of prior methods of lens-surface generation that derived the array of surface normal vectors required to match a source with a particular illumination prescription. This matching is done via grids on the unit sphere: one for the source and one for the prescription. The cells of these two grids are sized so that they have the same flux of lumens, according to the source intensity and the prescribed illumination, respectively. The first development is the use of an equi- flux polar grid for the target rectangle, because most light sources have circular symmetry. The second development is the radial segmentation of the lens surface in order to approximate the non-irrotational array of surface normal vectors derived from the two grids. Designs are presented for step-lighting by LEDs and fiber-optic billboard lighting.

Surface scatter effects are a dominant image degradation mechanism for very short X-ray wavelengths, even for state- of-the-art optical surfaces. And the severe off-axis aberrations of the classical Wolter Type I grazing incidence X-ray telescope consisting of a confocal paraboloid and hyperboloid severely limit the useful angular field that can be imaged onto a flat detector. A new family of alternative designs based on two hyperboloids has been developed that improves the wide-field imaging performance by aberration balancing and a compete optical systems engineering analysis. A particular member of this family, designed as H- T number 17, has been selected for use in the Solar X-ray Imager (SXI) instrument to be integrated into the NOA GOES satellite. The development of the SXI optical prescription and its defining parameters are first presented, then detailed image quality predictions, as degraded by diffraction effects, geometrical aberrations, surface scatter effects, and all other residual errors in the mirror manufacturers error budget tree are presented. This new optimized design yields an 80 percent increase in the number of spatial resolution elements over the full solar disc when compared to the classical Wolter Type I design that was the SXI baseline design.

The performance of an optical system can be degraded by the intrusion of stray light form sources both inside and outside of the system field of view. Stray light, or 'veiling glare,' can be particularly distracting in visual systems such as Helmet Mounted Display (HMD) systems. This paper describes techniques used by the authors to map stray light sources positions in the far field for HMD systems and to quantitatively define their impact. The mapping can be performed over 4(pi) steradians both inside and outside the system field of view. Monte-Carlo ray tracing algorithms are utilized for determining that separates the veiling glare component from the desired optical signal components. Once the major veiling glare source positions are identified, methods to reduce veiling glare can be determined. A technique for reducing noise in the calculation due to the statistical nature of the Monte Carlo ray trace is also discussed.

For staring, wide-field applications, such as a solar x-ray imager, the severe off-axis aberrations of the classical Wolter Type-I grazing incidence x-ray telescope design drastically limits the 'resolution' near the solar limb. A specification upon on-axis fractional encircled energy is thus not an appropriate image quality criterion for such wide-angle applications. A more meaningful image quality criterion would be a field-weighted-average measure of 'resolution.' Since surface scattering effects from residual optical fabrication errors are always substantial at these very short wavelengths, the field-weighted-average half- power radius is a far more appropriate measure of aerial resolution. If an ideal mosaic detector array is being used in the focal plane, the finite pixel size provides a practical limit to this system performance. Thus, the total number of aerial resolution elements enclosed by the operational field-of-view, expressed as a percentage of the n umber of ideal detector pixels, is a further improved image quality criterion. In this paper we describe the development of an image quality criterion for wide-field applications of grazing incidence x-ray telescopes which leads to a new class of grazing incidence designs described in a following companion paper.

The ROBS tracking telescope was invented and developed at TTC to provide a high acceleration,k large aperture beam steering system for rapid pointing to multiple objects. The optical system consists of a fast, oversized spherical primary mirror with the 50 cm aperture stop at the center of curvature of the primary mirror (CCP). A lightweight secondary mirror selects the instantaneous field of view by scanning over the petzval image surface of the primary mirror. The secondary mirror is gimbaled about the CCP on a rigid, lightweight mast. The system's symmetry about the CCP simplifies the optical and mechanical design and provides very rapid retargeting over a 30 degree field of regard for multiple target tracking. Field corrector and pupil relay optics inside the support tube collimate the light through coude' optics to passive sensor and laser radar optics. The 2-sphere, 2-asphere aplanatic, anastigmat all-reflective design corrects the 9.1 mr of spherical aberration from the F/1 primary and provides 10 microradian resolution over a 5 mr field of view. The system incorporates near field focus adjustment to provide high resolution imaging and laser ranging over a large volume of space. Two 50 cm systems have been built and demonstrated tracking multiple targets in the field. This paper describes the opto-mechanical design and demonstrated system capabilities.

Non-imaging integrator which can be used for laser beam homogenization in material processing with excimer laser radiation are analyzed with regards to geometrical and statistical optics. A model for the transversal degree of coherence of the laser radiation are analyzed with regards to geometrical and statistical optics. A model of the transversal degree of coherence of the laser radiation is presented in order to estimate the performance of the integrating devices for the partially coherent excimer laser radiation. This is necessary for a more relevant design of those elements than a design by geometric optical means only. The concept of non-imaging integrators is enhanced by separating the multifaceted element from the focusing lens. This separation provides more flexibility in the processing distance of the optical system. A further enhancement is the combination of such a system with an imaging lens in order to create a system which produces a top hat fluence distribution with variable size for materials processing applications.

A number of preliminary optical designs for a new generation of 4 meter astronomical survey telescopes have been investigated. These have large fields of view and operate in both the visible and near IR astronomical wavebands. Typical requirements for dual band systems of this type are presented. Two designs for prime focus refractive field corrector systems are presented, with and without aspheric surfaces. The use of aspheric surfaces on the field corrector lenses is shown to allow a large field of view to be achieved. A design for a three mirror reflective system is presented which also allows a 2 degree field to be achieved. An IR imager, based on a modified Schmidt camera, is presented which allows a 1 degree field of view to be achieved. Additionally, a modified Ritchey-Chretien telescope, incorporating refracting field corrector lenses is presented. This design provides a large field of view over both the visible and IR wavebands. The mechanical constraints of combining these systems into dual channel systems are also discussed.

This paper presents an approach for correcting conformal missile domes with a non-rotationally symmetric optical element called an arch. A parametric study in terms of aerodynamics, fineness ratio, maximum seeker look angle and dome index of refraction will demonstrate its capabilities for correcting conformal domes. A nomograph for trading optical performance versus relative missile range will also be presented.