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current developments in Lens design and optical engineering VIII

作者： Thibault, Simon Optics Division/Principal Optical Designer ImmerVision 2020 University Montreal QC H3A 2A5 Canada

ISBN: (纸本)9780819468154

During the last few years, innovative optical design strategies to generate and control image mapping have been successful in producing high-resolution digital imagers. This success has, in turn, increased the interest in the high-resolution camera and absolute measurement with high-resolution wide-angle lenses. This new generation of panoramic lenses includes catadioptric panoramic lenses, panoramic annular lenses, visible/IR fisheye lenses, anamorphic wide-angle attachments, and visible/IR panomorph lenses. Given that a wide-angle lens images a large field of view on a limited number of pixels, a systematic pixel-to-angle mapping will help the efficient use of each pixel in the field of view. In this study, the various relevant tradeoffs will be detailed and the advantages and disadvantages of panoramic lenses will be discussed. Of particular concern in the optical design of a panoramic imager is the uniformity of the image quality;because two hemispherical images can be stitched together digitally to form a complete 360-degrees X 360-degrees image, the performance of the lens at 90 degrees (preferably more than 90 degrees) is just as important as at the centre. Lateral colour, edge compression (distortion) and severe drop-off of the relative illumination can also present significant image defects and may cause seams in the immersive image. Finally, we will present various current scenarios where a high-resolution panoramic imager will be most advantageous.

关键词： optical instrument lenses

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Vision multiplexing: an optical engineering concept for low-vision aids

Vision multiplexing: an optical engineering concept for low-...

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Conference on current developments in Lens design and optical engineering VIII

作者： Peli, Eli Harvard Univ Sch Med Dept Ophthalmol Schepens Eye Res Inst Boston MA 02115 USA

ISBN: (纸本)9780819468154

The normal visual system provides a wide field of view apparently at high resolution. The wide field is continuously monitored at low resolution for navigation and detection of objects of interest. These objects are sampled using the high-resolution fovea, applying a temporal multiplexing scheme. Most vision impairments that cause low vision impact upon only one of the components;the peripheral low-resolution wide field or the central high-resolution fovea. The loss of one of these components prevents the interplay of central and peripheral vision needed for normal function and causes disability. Traditional low-vision aids improve the impacted component, but usually at a cost of a significant loss in the surviving component. For example, magnifying devices increase resolution but reduce the field of view, while minifying devices increase the field of view but reduce resolution. A general optical engineering approach - vision multiplexing - is presented. Vision multiplexing seeks to provide both the wide field of view and the high-resolution information in ways that could be accessed and interpreted by the visual system. The use of various optical and electro-optical methods in the development of a number of new visual aids, all of which apply vision multiplexing to restore the interplay of high-resolution and wide-angle vision using eye movements in a natural way, will be described. Vision-multiplexing devices at various stages of development and testing illustrate the successes and difficulties in applying this approach for patients with tunnel vision, hemianopia (half blindness), and visual acuity loss (usually due to central retinal disease).

关键词： bioptic telescope in-the-lens telescope IOL macular degeneration peripheral prisms retinitis pigmentosa

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Large-format telecentric lens

Large-format telecentric lens

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Conference on current developments in Lens design and optical engineering VIII

作者： Bai, Hanxiang Sadoulet, Samuel P. Edmund Opt Inc 101 E Gloucester Pike Barrington NJ 08007 USA

ISBN: (纸本)9780819468154

Research and development efforts to improve the performance of telecentric lens design for large-format cameras are driven by the ever-increasing deployment of these types of systems into the industrial Imaging arena. These lens designs typically have stringent requirements for contrast and resolution (> 30% at 1001p/mm) across large sensor sizes (up to 90mm) while maintaining both object- and image-space 91 telecentricity (0.1 degrees object-space, 0.2 degrees image-space). This paper explores various characteristics related to large-format telecentric lens designs and performance. In particular, details around advantages of afocal finite-conjugate imaging, mathematic expression for chromatic telecentricity, and desensitization of working distance variance are discussed with reference to geometric optics and aberration theory. Improvement of chromatic telecentricity and relief of requirement on image-distance accuracy are shown with graphics and MTF plots. Product parameter performance data is provided as an example.

关键词： large-format telecentric lens double telecentric lens telecentric lens large format machine vision lens telecentricity chromatic telecentricity afocal optical system desensitization

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Bi-centenary of successes of Fourier theorem: Its power and limitations in optical system designs

Bi-centenary of successes of Fourier theorem: Its power and ...

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Conference on current developments in Lens design and optical engineering VIII

作者： Roychoudhuri, Chandrasekhar U Connecticut & Femto Macro Continuum Storrs Dept Phys Photon Lab Storrs CT USA

ISBN: (纸本)9780819468154

We celebrate the two hundred years of successful use of the Fourier theorem in optics. However, there is a great enigma associated with the Fourier transform integral. It is one of the most pervasively productive and useful tool of physics and optics because its foundation is based on the superposition of harmonic functions and yet we have never declared it as a principle of physics for valid reasons. And, yet there are a good number of situations where we pretend it to be equivalent to the superposition principle of physics, creating epistemological problems of enormous magnitude. The purpose of the paper is to elucidate the problems while underscoring the successes and the elegance of the Fourier theorem, which are not explicitly discussed in the literature. We will make our point by taking six major engineering fields of optics and show in each case why it works and under what restricted conditions by bringing in the relevant physics principles. The fields are (i) optical signal processing, (ii) Fourier transform spectrometry, (iii) classical spectrometry of pulsed light, (iv) coherence theory, (v) laser mode locking and (vi) pulse broadening. We underscore that mathematical Fourier frequencies, not being physical frequencies, cannot generate real physical effects on our detectors. Appreciation of this fundamental issue will open up ways to be innovative in many new optical instrument designs. We underscore the importance of always validating our design platforms based on valid physics principles (actual processes undergoing in nature) captured by an appropriate hypothesis based on diverse observations. This paper is a comprehensive view of the power and limitations of Fourier Transform by summarizing a series of SPIE conference papers presented during 2003-2007.

关键词： Fourier transforms Spectroscopy Superposition Sensors Transform theory Physics Diffraction Time-frequency analysis Visibility

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Polarization dependent proximity effects

Polarization dependent proximity effects

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Conference on optical Microlithography XX

作者： Tyminski, Jacek. K. Matsuyama, Tomoyuki Nakashima, Tashiharu Schmoeller, Thomas Lewellen, John Nikon Precis Inc 1399 Shoreway Rd Belmont CA 94002 USA Synopsys Inc D-81737 Munich Germany Nikon Inc Kumagaya Saitama 3608559 Japan Synopsys Inc Mountain View CA 94043 USA

ISBN: (纸本)9780819466396

To meet the imaging resolution requirements, driven by the evolution of IC design rules, leading-edge scanners incorporate projection lenses with hyper-NAs. Moreover, immersion scanners are being introduced into IC manufacture. Both dry and immersion tools explore the lens design regimes of unprecedented complexity. The need to predict, to analyze and to control the IC pattern CDs is met by various photolithography simulators. The continuing demand for simulation accuracy is reflected by the requirement to quantify the scanner projection lens fingerprints, i.e. projection lens infinitesimal excursions from the ideal performance. The scanner engineering community has been relying on photolithography simulators to analyze the impact of the projection lens fingerprints on the imaging characteristics. However small, these excursions are always present in the projection tools and they control important imaging characteristics such as overlay, CD uniformity, across-field exposure latitude, to name but a few. Customarily, phase front aberrations and lens pupil apodization signatures have been used to predict the scanners imaging responses. Of course, the need to design, to manufacture and to deploy scanners of ever improving quality resulted in dramatic reductions of these non-ideal imaging excursions. The evolution of IC designs and imaging tools complexity escalate the requirements for imaging simulation accuracy. Simultaneously, predicting scanner imaging response has become a key mission in the Deign For Manufacture arena. In view of these developments, it necessary to pose a question if the conventional equipment engineering and imaging simulation methodologies predict scanner imaging responses with the accuracy required by the IC design rules. Differently put, the question is: what is necessary to provide simulation accuracy required by the current IC design rules? This report attempts to address these questions.

关键词： projection lens model vectorization wavefront aberrations optical proximity effects

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A design of real time image capturing and processing system using Texas instrument's processor

A design of real time image capturing and processing system ...

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Multimedia Systems and Applications X

作者： Wee, Toon-Joo Chaisorn, Lekha Rahardja, Susanto Gan, Woon-Seng Institute for Infocomm Research Singapore 119613 Singapore School of EEE Nanyang Technology University Singapore 639798 Singapore

ISBN: (纸本)9780819469373

In this work, we developed and implemented an image capturing and processing system that equipped with capability of capturing images from an input video in real time. The input video can be a video from a PC, video camcorder or DVD player. We developed two modes of operation in the system. In the first mode, an input image from the PC is processed on the processing board (development platform with a digital signal processor) and is displayed on the PC. In the second mode, current captured image from the video camcorder (or from DVD player) is processed on the board but is displayed on the LCD monitor. The major difference between our system and other existing conventional systems is that image-processing functions are performed on the board instead of the PC (so that the functions can be used for further developments on the board). The user can control the operations of the board through the Graphic User Interface (GUI) provided on the PC. In order to have a smooth image data transfer between the PC and the board, we employed Real Time Data Transfer (RTDX™) technology to create a link between them. For image processing functions, we developed three main groups of function: (1) Point Processing;(2) Filtering and;(3) 'Others'. Point Processing includes rotation, negation and mirroring. Filter category provides median, adaptive, smooth and sharpen filtering in the time domain. In 'Others' category, auto-contrast adjustment, edge detection, segmentation and sepia color are provided, these functions either add effect on the image or enhance the image. We have developed and implemented our system using C/C# programming language on TMS320DM642 (or DM642) board from Texas Instruments (TI). The system was showcased in College of engineering (CoE) exhibition 2006 at Nanyang Technological University (NTU) and have more than 40 users tried our system. It is demonstrated that our system is adequate for real time image capturing. Our system can be used or applied for application

关键词： Real time systems

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Proceedings of SPIE: current developments in Lens design and optical engineering VI

Proceedings of SPIE: Current Developments in Lens Design and...

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current developments in Lens design and optical engineering VI

The proceedings contain 27 papers. The topics discussed include: using multi-function components to solve optical design challenges for DUV microlithographic applications;automated synthesis of both the topology and numerical parameters for seven patented optical lens systems using genetic programming;advances in lenticular lens arrays for visual display;wide field-of-view imaging system using a liquid crystal spatial light modulator;design tools for freeform optics;designing and specifying aspheres for manufacturability;infrared hybrid optics with high broadband efficiency;removing challenges in microlithographic optical design;laser beam filtering by refractive or diffractive microstructures;and a hybrid athermal CCD camera.

关键词： optical design

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Balancing detector effects with aberrations in the design of wide-field grazing incidence x-ray telescopes

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optical engineering 2006年第6期45卷 063003-1-063003页

作者： Harvey, James E. Atanassova, Martina Krywonos, Andrey Univ Cent Florida CREOL Orlando FL 32826 USA

Most imaging systems today include a mosaic detector array in the focal plane. optical designers of astronomical telescopes typically produce a design that yields a superb on-axis aerial image in the focal plane, and detector effects are included only in the analysis of the final system performance. Aplanatic optical designs (corrected for spherical aberration and coma) are widely considered to be superior to nonaplanatic designs. However, there is little merit in an aplanatic design for wide-field applications because one needs to optimize some field-weighted-average measure of resolution over the desired operational field of view (OFOV). Furthermore, when used with a mosaic detector array in the focal plane, detector effects eliminate the advantage of the aplanatic design even at small field angles. For wide fields of view, the focal plane is frequently despaced to balance field curvature with defocus thus obtaining better overall performance. We will demonstrate that including detector effects in the optical design process results in a different optimal (nonaplanatic) design for each OFOV that is even superior to an optimally despaced aplanatic design. (c) 2006 Society of Photo-optical Instrumentation Engineers.

关键词： detector effects wide-field imaging systems grazing incidence x-ray telescopes

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Stabilization of the line of sight of a cryogenic optical system

Stabilization of the line of sight of a cryogenic optical sy...

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Conference on current developments in Lens design and optical engineering VII

作者： Ren, Qifeng Shen, Mangzuo Tan, Shuliang Liao, Sheng Chinese Acad Sci Inst Opt & Elect 4-9 Renminnan Rd Chengdu 610041 Peoples R China

ISBN: (纸本)0819463671

Cryogenic optical systems are often mounted in vacuum cryostat. An interesting concern in the mechanical design is how to maintain the stability of the line of sight (LOS) of the cryogenic optical system when it is cooled down to very low temperature. To investigate this problem an experimental cryogenic optical system, its mounting structure, and a cryostat were designed and fabricated. After assembling them together, a test experiment for measuring the LOS drift was carried out. Finally, the test results will be presented in this paper.

关键词： cryogenic optical system line of sight optomechanical design optical test

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An easy way to relate optical element motion to system pointing stability - art. no. 62880I

An easy way to relate optical element motion to system point...

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Conference on current developments in Lens design and optical engineering VII

作者： Burge, J. H. Univ Arizona Coll Opt Sci Tucson AZ 85721 USA

ISBN: (纸本)0819463671

The optomechanical engineering for mounting lenses and mirrors in imaging systems is frequently driven by the pointing or jitter requirements for the system. A simple set of rules was developed that allow the engineer to quickly determine the coupling between motion of an optical element and a change in the system line of sight. Examples are shown for cases of lenses, mirrors, and optical subsystems. The derivation of the stationary point for rotation is also provided. Small rotation of the system about this point does not cause image motion.

关键词： optical alignment optomechanics pointing stability geometrical optics

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