A simple closed form solution was derived for the optimum weight design of a cylindrical sandwich mirror for a given self-weight deflection and mirror radius. This optimum solution is based on the generalized deflecti...
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ISBN:
(纸本)0819437387
A simple closed form solution was derived for the optimum weight design of a cylindrical sandwich mirror for a given self-weight deflection and mirror radius. This optimum solution is based on the generalized deflection equation for an axisymmetrically supported thick circular plate. This two parameter equation of deflection captures the deflection of the plate caused by bending and transverse shear. The solution yields the optimum facesheet thickness, core thickness, and core density. The derived optimum solution was used in a case study for the GLAS (Geoscience Laser Altimeter System) primary mirror. This Beryllium mirror is manufactured with an open back isogrid pattern. The objective of this study is to determine a lightweight mirror design using Aluminum sandwich construction that can meet the performances of the current mirror and reduce fabrication costs. With the optimum solution several first order approximations using Aluminum honeycomb or foam core were determined. The performance, 1 g deflection, and wave front error of these designs was determined from Finite Element Analysis. The results conclude that sandwich construction outperforms the isogrid design by significant margins on both weight and distortion if the same material is used. Because of its superior specific stiffness the Beryllium isogrid design still marginally outperforms the optimum Aluminum sandwich design. However, the Aluminum sandwich design should provide significant advantages on cost and ease of fabrication over Beryllium isogrid designs.
currentdevelopments in computer technology give rise to increasing data communication over relatively short distances at backplane- and inter MCM interconnect level. It is foreseen that electrical interconnect will n...
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ISBN:
(纸本)0819435554
currentdevelopments in computer technology give rise to increasing data communication over relatively short distances at backplane- and inter MCM interconnect level. It is foreseen that electrical interconnect will not be able to accommodate the necessary data traffic in advanced data processing systems in the future and hence a bottleneck will be created. A potential remedy for this interconnect problem is the use of parallel optical datalinks. In this paper we propose small diameter step index plastic optical fiber ribbons in combination with high efficient resonant cavity LED's as a cheap and feasible option for these optical links. A design for such an optical link is presented with special, attention for the optical pathway. Experimental results on the optical properties of the used POF are shown. We describe the development of RCLED's at 850 nm specially designed for efficient coupling into POF. We measured a RCLED to POF coupling efficiency up to 40%. Additionally we report on the technologies used for the fabrication and assembly of the optical pathways and finally some experiments were carried out on the first realized assemblies.
The productive and accurate ablation of microstructures demands the precise imaging of st mask pattern onto the substrate under work. The job can be done with high performance wide field lenses as a key component of a...
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ISBN:
(纸本)0819437387
The productive and accurate ablation of microstructures demands the precise imaging of st mask pattern onto the substrate under work. The job can be done with high performance wide field lenses as a key component of ablation equipment. The image field has dimensions of 20 to 30 mm. Typical dimensions and accuracy of the microstructures are in the order of some microns. On the other hand, the working depth of focus (DOF) has to be in the order of some 10 microns to be successful on drilling through 20 to 50 mum substrates. All these features have to be reached under the conditions of high power laser UV light Some design principles for such systems are applied, such as optimum number of elements, minimum tolerance sensitivity, material restrictions for the lens elements as well as mechanical parts (mounting), restrictions of possible power densities on lens surfaces (including ghosts), matched quality for the manufactured system. The special applications require appropriate performance criteria for theoretical calculation and measurements, which allow to conclude the performance of the application. The base is wave front calculation and measurement (using Shack-Hartmann sensor) in UV. Derived criteria are calculated and compared with application results.
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...
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ISBN:
(纸本)0819432652
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.
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 pr...
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ISBN:
(纸本)0819432652
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 Next Generation Sky Survey (NGSS) 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...
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ISBN:
(纸本)0819432652
The Next Generation Sky Survey (NGSS) 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 focussed by three refractive camera systems onto four detector arrays. The nominal opticaldesign exceeds the requirement of diffraction limited performance at 8 microns wavelength over the 1 degree by 0.5 degree field of regard.
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...
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ISBN:
(纸本)0819432652
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 systems including optical performance, seam placement and binocular rivalry.
A number of optical plastic materials are examined. The indices of refraction are measured in the visible and near-infrared spectral regions from 435.8 nm to 1052 mn. Some obtained data and Abbe constants are presente...
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ISBN:
(纸本)0819432652
A number of optical plastic materials are examined. The indices of refraction are measured in the visible and near-infrared spectral regions from 435.8 nm to 1052 mn. Some obtained data and Abbe constants are presented. The glass libraries of the opticaldesign software packages are updated. The spherochromatic aberration balancing is analyzed during the all-plastic doublet and tripler 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 opticaldesign are drawn.
Some results obtained in the realization of compact relay systems design are presented. Four optical configurations have been analyzed. Two symmetrical schemes were examined having field Smith's lenses for a image...
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ISBN:
(纸本)0819432652
Some results obtained in the realization of compact relay systems design are presented. Four optical configurations have been analyzed. Two symmetrical schemes were examined having field Smith's lenses for a image scaling of-ix. 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 results and the optical systems performance are illustrated.
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 o...
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ISBN:
(纸本)0819432652
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 unobscued 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.
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