The subject of this paper relates to the ocular optical design and vision analysis of refractive correction of the eye. After the purpose statement and the assumption list, the concept of the schematic eye matching a particular (measured) wavefront is introduced. This concept is based on the fact that the ocular wavefront, together with the corneal topography, can be seen as the mathematical global representation of the eye working in monochromatic light and having a foveal vision. The discussed design technique, including an iterative optimization method, could be applied in any ocular correction that utilizes cornea topography and/or ocular wavefront, e.g. contact lens or intra-corneal implant. However, the application this paper refers to is the ocular refractive correction by a procedure using the LADARVISION. It consists of surgical removal and subsequent replacement of a corneal flap on a stromal surface whose shape has been changed by laser ablation of the tissue. Subsequent sections of this paper are dedicated to establishing the limits of possible refractive correction, the influences of the flap and corneal topography into the refractive correction calculation. Finally a realistic evaluation of the results and a list of possible developments of this new optical design method are discussed.
As part of the Infrared Eye project, this article describes the design of large-deviation, achromatic Risley prisms scanning systems operating in the 0.5 - 0.92 and 8 - 9.5 μm spectral regions. Designing these systems is challenging due to the large deviation required (zero - 25 degrees), the large spectral bandwidth and the mechanical constraints imposed by the need to rotate the prisms to any position in 1/30 second. A design approach making extensive use of the versatility of optical design softwares is described. Designs consisting of different pairs of optical materials are shown in order to illustrate the trade-off between chromatic aberration, mass and vignetting. Control of chromatic aberration and reasonable prism shape is obtained over 8 - 9.5 μm with zinc sulfide and germanium. The design is more difficult for the 0.5 - 0.92 μm band. Trade-offs consist in using sapphire with Cleartran® over a reduced bandwidth (0.75 - 0.9 μm ) or acrylic singlets with the Infrared Eye in active mode (0.85 - 0.86 μm). Non-sequential ray-tracing is used to study the effects of fresnelizing one element of the achromat to reduce its mass, and to evaluate detector narcissus in the 8 - 9.5 μm region.
In this paper we discuss the results given by the nominal design, tolerance analysis, and tests of aspheric CGH null. The optical testing configuration has been used contained a Zygo interferometer, a self-alignment CGH null and a convex aspheric surface under test with revolution symmetry. The CGH null design has been carried out while taking into consideration the parameters of the test surface such as focal ratio, axial coordinates of the test surface normal as function of radial height, as well as the diffractive technology limits. The worst case generated by Monte Carlo analysis of the tolerance has been used to determine the photolithography tolerances. Finally the CGH null testing results are compared with the nominal design and tolerance analysis predictions.
This paper presents the results given by the nominal design and tolerance analysis of a narrow-field-of-view camera lens equipped with a rotating prism scanning system. The first aspects taken into consideration have been the compensation of the chromatic aberration, distortion reduction, and the correlation between depth-of-field and lens resolution. Then, a rigorous approach to determine the relationship between the field-of-regard direction and the prism orientations is discussed. Finally, the tolerance analysis results give the predictable pointing direction precision as function of the system tolerances.
This paper treats three aspects of construction and use of deformable mirror devices developed at National Optics Institute: technology, optics configuration (functional equations), and diffraction (Fourier analysis).
Hughes ELCAN has developed a family of video projector zoom lenses. These lenses cover a large range of optical parameters, i.e. zoom ratio, F number, projection distance, LCD size. Most configurations use only two moving groups accomplishing zoom, compensation, and focus functions. This particular architecture allows the design of a well corrected compact zoom lens. This paper presents the procedures for initial design, using the paraxial optics equations, and the final system design using the Code V.
The paper proposes an optical arrangement for the control in real-time of the laser spot position in lithography techniques. The arrangement is adequately for the small installation, especially used in research or teaching activities.
This paper proposes two systems of Fresnel Zone Plates which could focus two parallel monochromatic and coherent beams (with different wavelengths), eliminating the wellknown chromatical aberrations of the classical construction.
A GEC-Marconi optically addressed spatial light modulator was used in a nonlinear joint transform correlator to demonstrate an application in speckle metrology. A particular input architecture used in this correlator potentially allows the design of a more compact correlator architecture.
A radial stretching of the phase only filter depending on the energy angular distribution of the target spectrum is used to perform shift and scale invariant pattern recognition. The complex conjugate of a basic size target Fourier transform and the cumulative energy angular distribution are calculated. Then the radially stretched filter providing the same energy contribution to the correlation peak independent on the target size is prepared and used in a conventional correlator, with spherical-wave illumination. The maximum scale ratio of recognizable objects equals 1:1.5. Computer simulations and experimental results, showing the performance of the filter are presented.
This paper tries to achieve two goals: studying the influence of certain parameters in Optical Computing, and then finding out the possibilities to improve the computation accuracy in Optical Information Processing Systems. A Computer Generated Complex Filter design, taking admissible error of Fourier Transform into account, has been demonstrated as an application of this study.
Technological realities are a severe limiting factor for the expected general use of optical cor- relation. This is a particularly crucial issue in view of the importance of the information co- ding on the signal to noise ratio. A current trade-off between phase and amplitude coding makes use of liquid cristals light valves (LCLV). This proposal describes an optical processor where the LCLV is addressed by a filtered image as writing beam and, in contrast with the usual plane wave, the Fourier transform of a modu- lated beam as read-out beam. This operating mode enables non standard use of available technologies ; in particular, due to double correlation, signal dynamics in the Fourier plane is a less stringent factor.
From lasers to spectrophotometers, reflecting microscope objectives are today finding a wealth of applications: reflecting objectives are widely used in the UV microlithography as well as in FTIR spectrophotometry, as part of the delivery system to focus the beam to precisely controlled spot sizes (e.g., for excimer laser beams--submicron size). Because of achromatism these objectives can be used simultaneously for aligning and viewing the targets. In the 'classical' layout the smaller mirror obstructs the central portion of the incident beam. The current paper describes a new solution to reduce the central obstruction by incorporating refracting components in the objective construction. We will discuss the conditions for aberrations correction and diffraction limitation as a function of both the focal length and aperture. Some examples of reflecting/refracting objectives (RRO) will be presented.
Matrices of optical components (like LEDs, microlenses, microzone plates, microspatial filters) are used in some arrangements to obtain the optical transformation from an area of a frontal plane to a point and vice versa. By use of these matrices the following arrangement are established: a matrix optical relay-system, a multichannel optoelectronic hybrid computer, an optical system for pattern recognition by spatial multichannel filtering, and uniform illumination system. The established relationships are applied to calculate the positions, the component sizes, and the system performance. Matrix configuration is shown to be advantageous for maximizing the performance for plane-point correlation and, also, for a miniature solution.
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