Nowadays, the development of the space apparatus with high optical characteristics still stays the important task. The simplest systems which can provide the required characteristics for remote monitoring from the spa...
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ISBN:
(数字)9781510620629
ISBN:
(纸本)9781510620629
Nowadays, the development of the space apparatus with high optical characteristics still stays the important task. The simplest systems which can provide the required characteristics for remote monitoring from the space are the three-mirror systems. It can be shown that in many cases, classical three-mirror systems have critical value of obscuration that leads to decreasing of resolution. Using off-axis field of view in the systems provides the way to avoid the obscuration influence. We present a technique for designing the three-mirror telescope objectives based on the systems with axial symmetry with an off-axis field of view.
The geometrical and diffraction point-spread functions of an optical imaging system have been reviewed and compared in the past [V. N. Mahajan, "Comparison of geometrical and diffraction point-spread functions,&q...
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ISBN:
(纸本)9781628417449
The geometrical and diffraction point-spread functions of an optical imaging system have been reviewed and compared in the past [V. N. Mahajan, "Comparison of geometrical and diffraction point-spread functions," SPIE Proc. 3729, 434-445 (1999)]. In this paper, we review and compare its corresponding optical transfer functions. While the truth lies with the diffraction OTF, it is considered easier and quicker to calculate the geometrical Oil, especially for large aberrations. We briefly describe the theory of the two OTFs, and explore the range of spatial frequencies and the magnitude of the primary aberrations over which the geometrical OTF may provide a reasonable approximation of the diffraction OTF.
Recently, the display device was developed to apply to the transparency display device(TDD), but the TDD was no brightness. The purpose of this paper was introduced a double layer optical film to improve luminance of ...
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ISBN:
(数字)9781510602861
ISBN:
(纸本)9781510602854;9781510602861
Recently, the display device was developed to apply to the transparency display device(TDD), but the TDD was no brightness. The purpose of this paper was introduced a double layer optical film to improve luminance of the TDD. The film was doped micro metal oxide particles to increase the effect of scattering and refraction, and the micro structure was fabricated between the top and bottom film to enhance the light into the TDD. This research provided a transparent double layer optical film. The transparency of the film was achieved to 70 %, and the brightness efficiency up to 60 %.
optical system design is undergoing a transformational change with the increases in computational horsepower, cutting-edge algorithmic developments, and the advent of new nanofabrication technologies. Among the most e...
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ISBN:
(纸本)9781510654198;9781510654181
optical system design is undergoing a transformational change with the increases in computational horsepower, cutting-edge algorithmic developments, and the advent of new nanofabrication technologies. Among the most exciting advances in recent memory are optical metasurfaces, which are patterned surfaces commonly realized through nanofabrication that can imbue optical engineers with expanded degrees of design freedom due to their ability to exploit the generalized form of Snell's law. Through intelligent optimization and design, metasurfaces can be constructed which achieve arbitrary chromatic dispersion behaviors and unprecedented control over polarization that simply cannot be realized with conventional optical elements. However, designing high-performance metasurfaces requires the use of full-wave simulation tools and numerical optimization techniques which necessitate considerable computational resources. Moreover, while optical metasurfaces are moving towards millimeter and centimeter scale diameter lenses with advances in nanofabrication techniques, it is computationally infeasible to employ full-wave simulation tools directly to model optical systems that use such large size elements. Nevertheless, the size, weight, and power (SWaP) advantages afforded by optical metasurfaces make them a compelling choice for designers to consider in a number of applications, which are currently limited by bulky conventional optical solutions. Therefore, techniques that can rapidly model metasurfaces in conjunction with conventional optical elements such as lenses, mirrors, and prisms are highly desirable. In this presentation, we highlight a toolkit of custom solvers, design procedures, and powerful optimization algorithms that simplify and accelerate the development of hybrid optical systems with arbitrary combinations of conventional and metasurface elements.
We study the formation of caustic produced by smooth arbitrary surfaces considering a plane wavefront propagating parallel to the optical axis and impinging on the refracting surface. We have already seen that the sha...
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ISBN:
(纸本)9781628412192
We study the formation of caustic produced by smooth arbitrary surfaces considering a plane wavefront propagating parallel to the optical axis and impinging on the refracting surface. We have already seen that the shape of the caustic surface can represent the monochromatic aberrations that we call image errors, furthermore the shape of the caustic can be modified by changing the parameters of the lens in such a way that if the caustic surfaces is vanished the optical system produces a perfect image, on the other hand for a caustic possessing a large area it could be applied to design no-imaging optical systems. The shape of the caustic depends only on the indices of refraction involved in the process of refraction, the refracting surface which is formed by smooth arbitrary plano-convex lens. We provide an analytic equation for the caustic surface after refraction of a plane wave from every rotationally symmetric surface.
developments of an optical-fibre-based sensor system for monitoring residual chlorine in water are discussed. The system, based on differential absorption spectroscopy, utilizes a novel miniature monolithic diode arra...
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developments of an optical-fibre-based sensor system for monitoring residual chlorine in water are discussed. The system, based on differential absorption spectroscopy, utilizes a novel miniature monolithic diode array spectrometer operating in the ultraviolet and visible (UV-Vis) region of the spectrum in combination with an optical flow-through cell of length 430 mm and a computer-controlled deuterium lamp source. The sensor, having a detection limit of 0.2 mg l(-1) of free chlorine in water, relies on the fact that the OCl- ion, in which form dissolved chlorine exists at high pH (> 9), strongly absorbs light at 290 nm. This paper describes the systematic approach that is used in the modelling and design of this sensor system. It also outlines the construction of the device and gives an evaluation of the performance in the laboratory environment.
This paper proposes the design of an anastigmatic three-mirror telescope using freeform surfaces for the correction of spherical aberration, coma, astigmatism, and field curvature, allowing a wide field of view (FOV) ...
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ISBN:
(数字)9781510637719
ISBN:
(纸本)9781510637719
This paper proposes the design of an anastigmatic three-mirror telescope using freeform surfaces for the correction of spherical aberration, coma, astigmatism, and field curvature, allowing a wide field of view (FOV) and high resolution. For the structure of this telescope, it is proposed to use only two optical elements where the primary and tertiary mirrors are integrated into an only optical element and the secondary mirror in the other, thus achieving a considerable reduction in the difficulty of alignment and assembly. To achieve a high performance of the telescope, the system was decentered (off-axis design), avoiding the loss of energy due to the obscuration of the M-2 in the on-axis system. In addition, to solve the difficult access to the focus.
作者:
Huegele, VBNASA
George C Marshall Space Flight Ctr SOMTC Huntsville AL 35812 USA
A segmented array of mirrors was designed for a solar concentrator test stand at MSFC for firing solar thermal propulsion engines. The 144 mirrors each have a spherical surface to approximate a parabolic concentrator ...
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ISBN:
(纸本)0819437387
A segmented array of mirrors was designed for a solar concentrator test stand at MSFC for firing solar thermal propulsion engines. The 144 mirrors each have a spherical surface to approximate a parabolic concentrator when combined into the entire 17-foot diameter array. The mirror segments are aluminum hexagons that had the surface diamond turned and quartz coated. The array focuses sunlight reflected from a heliostat to a 4 inch diameter spot containing 8 kilowatts of power at the 15 foot focal point. The derivation of the surface figure for the respective mirror elements is shown. The alignment process of the array is discussed and test results of the system's performance are given.
An optical system application required a high speed laser scanning subsystem that produced high quality extended images focused at 32 discrete separated positions along a line, rather than continuously varying positio...
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ISBN:
(纸本)9780819472809
An optical system application required a high speed laser scanning subsystem that produced high quality extended images focused at 32 discrete separated positions along a line, rather than continuously varying positions along the line as in more familiar scanning systems. This paper describes the opticaldesign trades and selection of a grating-based scan element that produces this unusual type of scan, and the opticaldesign methods that corrected aberrations produced by the scan element. A variety of different grating-based scan element designs were explored, in a flat disk geometry, but these produced excessive aberrations, both in the absolute level and in the magnitude of variation with scan. A ring-shaped scan element geometry was identified, which greatly minimized the scan-varying aberrations and brought them to near acceptable levels. Additional cylindrical corrector elements were added near the ring scan element to reduce the astigmatism of the ring substrate, and cylindrical lenslets were placed near the focus to provide further independent correction of astigmatism in each scan position. The resulting design achieved diffraction limited wavefront quality across the scan range.
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