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conference on current developments in lens design and optical engineering III

作者： Akram, MN Royal Inst Technol Dept Microelect & Informat Technol SE-16440 Stockholm Sweden

ISBN: (纸本)0819445347

In this paper, the design of a dual field-of-view optical system for 3-5 mum infra-red focal-plane arrays is described. Preliminary calculations are done to determine the first-order parameters of the narrow and the wide-field modes. To achieve a switchable dual field-of-view system, two different optical configurations, one based on the axial motion of a lens group and the other based on a rotate-in motion of two separated lens groups, are studied and compared. Diffractive and conic surfaces are used to control the color and the monochromatic aberrations with less number of total lenses used. Paraxial and real-ray modelling of the Narcissus effect is described. It is shown that the rotate-in scheme achieves better optical performance in both the narrow and the wide-field modes. The axial-motion scheme suffers from poor lateral color in the wide-angle mode. The final optical designs along with their aberrations curves and MTF plots are presented showing excellent performance.

关键词： lens design infrared optics diffractive optics dual field-of-view focal-plane-arrays (FPA)

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The impact of zonal irregularity on infrared lens performance 6

The impact of zonal irregularity on infrared lens performanc...

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current developments in optical design and engineering VI conference

作者： Sinclair, RL Wescam Inc 45 Innovation Drive Flamborough L9H 7L8 ON Canada

ISBN: (纸本)0819422517

High performance infrared optical designs require careful tolerancing to ensure that the as built performance meets the system requirements. Using modem optical design programs a wide variety of single element and group tolerances can be defined and statistical analysis employed to formulate a prediction of the as built performance. When the number of units being produced is small or near diffraction limited performance is required, then a worst case analysis is often employed to generate a more accurate prediction. However, in some situations, such as low F/number lenses, certain effects that may be important are not always adequately addressed by first order tolerance analysis. This paper reviews one such effect;zonal irregularity or slope errors. To quantify the impact of zonal irregularity on the MTF performance of an infrared lens, detailed comparisons are made between measured and predicted performance. Interferometric analysis of the lens element irregularity is incorporated within the design to predict the as built lens line spread function.

关键词： infrared lens optical tolerances interferograms

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F-sin(theta) lens system and applications

F-sin(theta) lens system and applications

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conference on current developments in lens design and optical engineering II

作者： Thibault, S INO Opt Engn Div St Foy PQ G1P 4S4 Canada

ISBN: (纸本)0819441554

Introducing the desired amount of distortion in an optical system is possible and relatively straight forward for optical designer. Known f-theta lenses used in laser scanner system is one of the most popular lenses of this type. With the development of DWDM system, compact spectrometer and various grating based devices, the interest in solving optical problems with innovative optical design has been a revival. On the other hand, it is possible to simplify considerably the task of the software by designing more sophisticated optical element. The F-sin(theta) lens is such a device which can be used in various grating based devices to improve the performance. This optical device is intended to provide a new lens or lens group which can be used with a diffraction grating to provide a linear output plane with the wavelength (lambda), but also with the order of diffraction (m), or with the grating spatial frequency, or with the inverse of the index of refraction (l/n). Based on theoretical consideration, we calculated which amount of distortion is desired to get linear output plane for a grating based device. We present singlet. achromatic doublet and mirror having this characteristic. These F-sin(theta) lenses present satisfactory distortion charateristic and have an improved correction for the curvature of image plane. F-sin(theta) lens will be also name F-lambda lens.

关键词： WDM DWDM distortion optical design aberration grating spectrometer

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Distortion controlled optical design using orthogonal surface polynomials 11

Distortion controlled optical design using orthogonal surfac...

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conference on current developments in lens design and optical engineering XXI

作者： Allain, Guillaume Thibault, Simon Ctr Opt Photon & Laser Quebec City PQ Canada Univ Laval Dept Phys Genie Phys & Opt Quebec City PQ Canada

ISBN: (数字)9781510637719

ISBN: (纸本)9781510637719

The design of high quality very wide-angle optical systems (FFOV > 100 degrees) relies on distortion to obtain a sufficient resolution at, usually, the center of the field of view. Using distortion shape as a parameter during optimization to reach a magnification target is a common technique to achieve optical foveation during the lens design process. This method allows resolution enhancement at selected parts of the field of view since less care is given to parts of the image that are deemed less important. However, accurate control of distortion can be a challenge during optical design since the standard aspherics polynomials don't correlate directly to image magnification. This may in fact slow down optimization since the merit function is much less optimized to approach a solution. In this paper, we address this problem by presenting a method to simplify distortion control during the optical design phase. To achieve this, the use of orthogonal polynomials is used for defining the optical surface shape and will then be used to compare the height of the image plane at a given field of view. We show that in the case of simple and paraxial system, this process is orthogonal and achieve a solution in a single optimization step. We will finally discuss the limits of this method and how it applies to modern lens design problems.

关键词： optical design Foveated imaging Distortion Control Orthogonal polynomials Shape specification

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Linear wavelength spectrometer

Linear wavelength spectrometer

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conference on current developments in lens design and optical engineering II

作者： Thibault, S INO Opt Engn Div St Foy PQ G1P 4S4 Canada

ISBN: (纸本)0819441554

Generally, a spectrometer uses a diffraction grating to spread the spectral components of a light incident on the diffraction grating on a one-dimensional detector. The detector is composed of pixels linearly distributed along a line. However, the diffracted light is not spread linearly on the detector which means that the Wavelength on pixel I is not linearly correlated with the wavelength on pixel 2. The resolution is therefore not constant for all the spectral range of the spectrometer. To know which pixel corresponds to which wavelength, a nonlinear calibration process must be applied to get a linear relation between the diffracted light position and the wavelength of this light. The new spectrometer that we present uses a special lens configuration name F-sin(theta) lens to provide a linear relation in the image plane between the pixel position and the wavelength of the light. The f-sin(theta) characteristic is defined as the difference in percent between the design position of the wavelength in the image plane and its ideal position, if the lens is perfect. The characteristic of the lens used in the spectrometer is better than 0.1%. The concept can also be used for WDM and DWDM applications.

关键词： spectrometer WDM DWDM distortion optical design guided optics

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A novel approach for structural synthesis of zoom systems

A novel approach for structural synthesis of zoom systems

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conference on current developments in lens design and optical engineering XI - and Advances in Thin Film Coatings VI

作者： Hazra, L. N. Pal, S. Univ Calcutta Dept Appl Opt & Photon Kolkata India

ISBN: (纸本)9780819482822

A new approach for 'ab initio' synthesis of thin lens structure of zoom lenses is reported. This is accomplished by an implementation of evolutionary programming, based on Genetic Algorithm, which explores the available configuration space formed by powers of individual components and inter-component separations. Normalization of the variables is carried out to get an insight on the optimum structures. The method has been successfully used to get thin lens structures of mechanically compensated, optically compensated, and linearly compensated zoom lens systems by suitable formulation of merit function of optimization. Investigations have been carried out on three component and four component zoom lens structures. Illustrative numerical results are presented.

关键词： optically compensated zoom lenses mechanically compensated zoom lenses evolutionary programming genetic algorithm thin lens design

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Barium Fluoride and glass combinations for short-wave infrared designs

Barium Fluoride and glass combinations for short-wave infrar...

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conference on current developments in lens design and optical engineering XI - and Advances in Thin Film Coatings VI

作者： Warren, D. W. Aerosp Corp Visible & Infrared Sensor Syst Dept Los Angeles CA 90009 USA

ISBN: (纸本)9780819482822

Achromatic doublet theory is recast for the 1-2.5 mu m short-wavelength infrared band, suggesting the desirability of combining barium fluoride with specific high index optical glasses having large differences in primary SWIR dispersion and small differences in partial SWIR dispersion. Candidate combinations of materials are screened empirically using the performance of optimized f/3 airspaced achromatic doublets employing barium fluoride as the positive element. Polychromatic RMS geometric image spot sizes appear to increase quadratically with difference in partial SWIR dispersion between barium fluoride and the complementary glasses. Examples of complex (fast, wide field) systems demonstrate the utility of the most promising combinations.

关键词： lens design infrared barium fluoride achromatic astronomy

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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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Optimization and fabrication of micro diffractive lens arrays for biochip application

Optimization and fabrication of micro diffractive lens array...

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conference on current developments in lens design and optical Systems engineering

作者： Yang, R Pang, L Wu, MX Jin, GF Tsing Hua Univ Dept Precis Instrument State Key Lab Precis Measurement Technol & Instru Beijing 100084 Peoples R China

ISBN: (纸本)0819437387

In the latest ten years, great efforts have been taken to miniaturize the biochemical and chemical analysis systems, and many kinds of biochips with functions of biology sample preparing, chemical assay reacting and result detecting, or mixture of some of these functions have been reported. An aspherical micro lens array with large numerous aperture is developed for a biosensor to achieve high fluorescence collection and high sensitivity. The optimized design and fabrication with new organic-inorganic sol-gel materials of micro lens arrays are discussed in this paper. Because of merits of micro size, low cost, facility to reproduce, flexibility to design and multi-channels detection, these elements are suitable to form a compact, multi-channel fluorescence biosensor that can address multiple biology samples simultaneously without loss in detection sensitivity. Packaging and alignment strategies for a sensor consist of micro lens arrays detecting fluorescence labeled DNA assay arrays are also presented, which is promising to be integrated into a micro total analysis system (u-TAS).

关键词： micro lens arrays organic-inorganic sol-gel biosensor u-TAS

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Development and Experimental Verification of an Intraocular Scattering Model

Development and Experimental Verification of an Intraocular ...

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conference on current developments in lens design and optical engineering XII/Advances in Thin Film Coatings VII

作者： Jiang, Chong-Jhih Jhong, Tian-Siang Chen, Yi-Chun Sun, Ching-Cherng Natl Cent Univ Dept Opt & Photon Jhongli 320 Taiwan

ISBN: (纸本)9780819487384

An intraocular scattering model was constructed in human eye model and experimentally verified. According to the biometric data, the volumetric scattering in crystalline lens and diffusion at retina fundus were developed. The scattering parameters of cornea, including particle size and obscuration ratio, were varied to make the veiling luminance of the eye model matching the CIE disability glare general formula. By replacing the transparent lens with a cataractous lens, the disability glare curve of cataracts was generated and compared with that of transparent lenses. The MTF of the intraocular scattering model showed nice correspondence with the data measured by a double-pass experiment.

关键词： intraocular scattering volumetric scattering veiling luminance disability glare cataractous lens double pass

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