Calculation of Axial Polychromatic Optical Transfer Function
TL;DR: In this article, a computer program has been developed and calculated results are compared with measurements, and the formulae necessary to extend from the monochromatic to the polychromatic OTF are developed for the axial case.
Abstract: Polychromatic or white-light OTF is put forward as a criterion of image quality for systems under actual working conditions. The formulae necessary to extend from the monochromatic to the polychromatic OTF are developed for the axial case. A computer programme has been developed and calculated results are compared with measurements.
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TL;DR: This work begins with a conceptual framework including the formulation of a psychophysical linking hypothesis that underlies the utility of image quality metrics based on the polychromatic point-spread function, and outlines strategies for computing polychrome point- spread functions of the eye when monochromatic aberrations are known for only a single wavelength.
Abstract: Although the retinal image is typically polychromatic, few studies have examined polychromatic image quality in the human eye. We begin with a conceptual framework including the formulation of a psychophysical linking hypothesis that underlies the utility of image quality metrics based on the polychromatic point-spread function. We then outline strategies for computing polychromatic point-spread functions of the eye when monochromatic aberrations are known for only a single wavelength. Implementation problems and solutions for this strategy are described. Polychromatic image quality is largely unaffected by wavelength-dependent diffraction and higher-order chromatic aberration. However, accuracy is found to depend critically upon spectral sampling. Using typical aberrations from the Indiana Aberration Study, we assessed through-focus image quality for model eyes with and without chromatic aberrations using a polychromatic metric called the visual Strehl ratio. In the presence of typical levels of monochromatic aberrations, the effect of longitudinal chromatic aberration is greatly reduced. The effect of typical levels of transverse chromatic aberration is virtually eliminated in the presence of longitudinal chromatic aberration and monochromatic aberrations. Clinical value and limitations of the method are discussed.
81 citations
TL;DR: In this paper, the theory of optical transfer functions in 3D imaging is presented, with a focus on suitable methods for the establishment of calibration standards for 3D images and surface topography measurements.
Abstract: A significant number of areal surface topography measuring instruments, largely based on optical techniques, are commercially available. However,implementation of optical instrumentation into production is currently difficult dueto the lack of understanding of the complex interaction between the light and the component surface. Studying the optical transfer function of the instrument can help address this issue. Herea review is given of techniques for the measurement of optical transfer functions. Starting from the basis of a spatially coherent, monochromatic confocal scanning imaging system, the theory of optical transfer functions in three-dimensional (3D) imaging is presented. Further generalizations are reviewed allowing the extension of the theory to the description of conventional and interferometric 3D imaging systems. Polychromatic transfer functions and surface topography measurements are also discussed. Following presentation of theoretical results, experimental methods to measure the optical transfer function of each class of system are presented, with a focus on suitable methods for the establishment of calibration standards in 3D imaging and surface topography measurements.
79 citations
Cites background from "Calculation of Axial Polychromatic ..."
...Considering the basic imaging equations it can be seen that polychromatic shift invariance will not hold if the magnification of the imaging system is strongly wavelength dependent [80]....
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TL;DR: It is shown that the assumption of conventional spectacle lens design techniques is generally valid, and it is possible that the use of complex aspheric surfaces, particularly for high powered lenses, may produce considerable lens coma with detrimental effects on foveal image quality of the rotating eye.
Abstract: This paper investigates whether or not the application of modern methods of optical design assessment to the field of spectacle lens design will recommend new designs and/or new principles for design of single vision spectacle lenses. The aspects of the assumption of conventional spectacle lens design techniques, which is that the finite size of the stop can be ignored, are discussed. The tools for the investigation, raytracing and polychromatic optical transfer function schemas, are also discussed. Using examples, it is shown that the assumption of conventional spectacle lens design techniques is generally valid. In general, the application of modern methods of optical lens design assessment to the field of spectacle lens design does not recommend designs or principles for design other than those already recommended by conventional spectacle lens design techniques. However, it is possible that the use of complex aspheric surfaces, particularly for high powered lenses, may produce considerable lens coma w...
33 citations
TL;DR: The model presented here provides a technique for estimating retinal image quality for the S, M and L cones for any stimulus presented to the eye and is applied to some informative examples.
21 citations
Cites background from "Calculation of Axial Polychromatic ..."
...With broadband light, the retinal image is determined by decomposing the point of light into its spectral components; the PSF is applied separately at each wavelength (Barnden, 1974; Ravikumar, Thibos, & Bradley, 2008)....
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...…spectral homogeneity where every point in the image emits the same relative radiance spectrum, or when the full spectral distribution is uniquely determined by the trichromatic specification; Barnden, 1974; Ravikumar, Thibos, & Bradley, 2008), these conditions rarely occur in the natural world....
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...…a,b,⇑ a Psychology, University of Chicago, 940 E. 57th Street, Chicago, IL 60637, USA b Ophthalmology & Visual Science and Institute for Mind & Biology, University of Chicago, 940 E. 57th Street, Chicago, IL 60637, USA c Ecole Polytechnique de l’Université de Nantes, IRCCyN, Rue Ch. Pauc, La…...
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TL;DR: In this article, the ambiguity function of the generalized pupil function of an optical system is a display of all the monochromatic OTFs with the longitudinal chromatic aberration as variable.
15 citations
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TL;DR: In previous OTF computer programs, various geometrical optical aspects of image formation appear often to have been ignored, leading to considerable errors in the computed values of the transfer function, particularly for high-aperture or wide-angle systems.
Abstract: In previous OTF computer programs, various geometrical optical aspects of image formation appear often to have been ignored. The neglect of factors associated with anamorphotic imagery, pupil aberrations and vignetting, and a shift of focal plane can lead to considerable errors in the computed values of the transfer function, particularly for high-aperture or wide-angle systems. In addition, the numerical integration processes employed have not always been entirely satisfactory in terms of efficiency, generality, and convenience.
36 citations
TL;DR: A general study of the design of lenses of double Gauss type and derivatives of these has been carried out, with the lenses optimized at an aperture of f/2 and a field angle of +/-20 degrees.
Abstract: A general study of the design of lenses of double Gauss type and derivatives of these has been carried out, with the lenses optimized at an aperture of f/2 and a field angle of ±20°. The results indicate that the number of optimized designs is small for all of the constructions that were investigated. Numerical examples for several designs are given.
13 citations
8 citations