Recent advances in axial gradient material fabrication via the diffusion of glass plates has opened the door to a wide variety of opticaldesign applications incorporating entire lenses of gradient index material. A p...
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ISBN:
(纸本)081941249X
Recent advances in axial gradient material fabrication via the diffusion of glass plates has opened the door to a wide variety of opticaldesign applications incorporating entire lenses of gradient index material. A proprietary software-driven process developed at LightPath Technologies Inc. creates gradient index glass by fusing together a stack of discrete glass plates, where each constituent plate has a distinctive composition and desired optical properties. LightPath's ability to prescribe large optical index changes (up to 0.47) throughout a glass substrate of virtually any diameter and thickness (macro gradient), invokes an interesting question: what are the properties of a solid gradient index lens and how can these properties be used most efficiently and effectively? This paper reports on a parametric study of third order spherical aberration vs. shape factor, for a macro gradient F/3 singlet lens whose index varies by ± 0.4 in linear, quadratic and cubic profiles.
Using the Lockheed in-house computer program OPTIMA for opticaldesign and analysis, a facility has been implemented which enables the opticaldesigner to target any performance parameter at any temperature in the ran...
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ISBN:
(纸本)081941249X
Using the Lockheed in-house computer program OPTIMA for opticaldesign and analysis, a facility has been implemented which enables the opticaldesigner to target any performance parameter at any temperature in the range of interest. A database with thermal properties of the optical materials was added to the program along with routines facilitating the evaluation of an optical system at arbitrary temperatures. In the optimization section of the program, alternate lens configurations are used to represent the lens at different temperatures. During the optimization the program automatically changes temperature and computes the requested performance parameters at the desired temperatures. Applications for this method include the design of high-performance camera objectives optimized for a large temperature range.
A photographic objective employing axial gradient-index (GRIN) elements is described and compared with a conventional double Gauss lens. Comparable imaging performance and increased relative illumination at the edge o...
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ISBN:
(纸本)081941249X
A photographic objective employing axial gradient-index (GRIN) elements is described and compared with a conventional double Gauss lens. Comparable imaging performance and increased relative illumination at the edge of field are realized in the GRIN design even though it has fewer optical elements.
The use of a standard aspheric profile to describe conventional optical elements in lensdesign programs has advantages such as independent verification of lens system performance by different individuals, ease of int...
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ISBN:
(纸本)081941249X
The use of a standard aspheric profile to describe conventional optical elements in lensdesign programs has advantages such as independent verification of lens system performance by different individuals, ease of interpretation by different manufacturers, etc. A model of diffractive optical element is proposed for consideration as a standard form to have similar benefits. Diffractive elements are characterized here by (1) the equation of the supporting surface (substrate), and (2) the phase function. The phase function itself consists of two terms: (a) the stigmatic phase term, and (b) the astigmatic phase term. The stigmatic phase term is a rotationally symmetric function and is related to the property of the diffraction element to image free from aberration one axial point onto another, as in holograms, at a specific (reference) wavelength. The astigmatic phase term is an arbitrary function of the space coordinates, it takes several forms: it can impart aspheric deformations (or corrections) to incident wave fronts or it can be used to model different types of gratings.
In the first part of this paper, we examine previously used methods for the assessment of the subjective performance of lenses coupled to the eye, we establish the need for a unified means of assessment in terms of vi...
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ISBN:
(纸本)081941249X
In the first part of this paper, we examine previously used methods for the assessment of the subjective performance of lenses coupled to the eye, we establish the need for a unified means of assessment in terms of visual tasks and targets, and we propose such a means. In the second part, we address some common aberration balancing questions, with a view to presenting concrete recommendations for opticaldesign. The balancing questions examined are: defocus and accommodation, accommodation and longitudinal color, spherical aberration and defocus, astigmatism and field curvature, field curvature and accommodation, transverse color and astigmatism, and coma and astigmatism.
For many illumination applications, it is desirable for a laser beam to have a uniform irradiance distribution across its diameter. Refractive and reflective systems for reshaping a laser beam profile have been propos...
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ISBN:
(纸本)081941249X
For many illumination applications, it is desirable for a laser beam to have a uniform irradiance distribution across its diameter. Refractive and reflective systems for reshaping a laser beam profile have been proposed and discussed for many years. One of the refractive systems consisting of two plano-aspherical lenses operates with high efficiency. Recently, a prototype of this two aspherical lens reshaping system has been made from CaF2. The performance of the prototype is presented in this paper. The opticaldesign and analysis of this system also are discussed.
Phase measuring interferometry is well established as the premier measurement technology in support of optical component fabrication. Commercial instruments are available that provide surface measurements over a range...
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ISBN:
(纸本)081941249X
Phase measuring interferometry is well established as the premier measurement technology in support of optical component fabrication. Commercial instruments are available that provide surface measurements over a range of radii and diameters. However, microlithographic lenses have increased in complexity and scale to the point that most commercial instruments fail to provide adequate surface coverage. Most severe is the ability to measure large diameter, convex surfaces. Anticipating the demands of today's microlithographic lens production, Tropel began design and construction of a new class of phase measuring interferometers in 1990. As a catadioptric design, these instruments feature a large spherical mirror to accomplish their purpose. This paper reviews the opticaldesign of the large aperture reflective interferometer (LARI), and various considerations in their construction.
The new Intense Point Source (IPS) consists of the regular linear Xenon flash tube mounted in a newly patented Orthogonal Parabolic Reflector (OPR) (Patent No. 5,037,191). The system integrates the radiation for the l...
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ISBN:
(纸本)081941249X
The new Intense Point Source (IPS) consists of the regular linear Xenon flash tube mounted in a newly patented Orthogonal Parabolic Reflector (OPR) (Patent No. 5,037,191). The system integrates the radiation for the long linear lamp into a very small point on the order of 3 to 6 millimeters in diameter, with a 90° divergent angle. A diffuser and lens systems are employed to provide either a narrow beam of a few degrees for long range photography or a diffused light for close-up photography to provide softened, penetrating lighting. Light intensity distribution data for the new flash system as compared to that of the original Vivitar 285 flash lamp as measured in the Vivitar lab, are presented.
Axial gradient index lens blanks with values of Δn up to 0.5, thicknesses and diameters up to 25 and 200 mm, respectively, have been produced by fusing together thin layers of glasses of progressively different indic...
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ISBN:
(纸本)081941249X
Axial gradient index lens blanks with values of Δn up to 0.5, thicknesses and diameters up to 25 and 200 mm, respectively, have been produced by fusing together thin layers of glasses of progressively different indices of refraction. Smooth, step-free gradients are formed by controlled diffusion within and across the layers. Computer software has been developed to prescribe the gradient index profile and to control the diffusion process. Linear, quadratic, cubic, and a variety of other gradient index profiles can be produced by this method over a wide refractive index range. This paper discusses the diffusion software, process and metrology for a gradient blank currently in process to be used in a varifocal slide projector prototype.
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