Results 181 to 190 of about 1,870,110 (224)
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Diffractive Bifocal Intraocular Lens
SPIE Proceedings, 1989A bifocal intraocular lens is described which has been surgically implanted in a number of patients in the United States and Europe with promising results. The posterior surface of this lens includes a blazed phase zone plate which directs most of the light to two diffractive orders.
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Modeling diffraction efficiency effects when designing hybrid diffractive lens systems
Applied Optics, 1992We investigated the design of two broadband hybrid diffractive-refractive optical systems, a landscape lens, and a Schmidt telescope. The systems were achromatized by using the characteristically large negative dispersion of kinoforms. In the scalar wave regime kinoforms can approach 100% efficiency but only for one object point and wavelength.
C, Londoño, P P, Clark
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Dermatologic Surgery, 2019
BACKGROUND The diffractive lens of the picosecond laser is relatively new, and there are few reports on its efficacy in treating atrophic acne scars, especially in Asian populations. OBJECTIVE Evaluating the efficacy of diffractive lens 755-nm picosecond
Ching-Hsin Huang +3 more
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BACKGROUND The diffractive lens of the picosecond laser is relatively new, and there are few reports on its efficacy in treating atrophic acne scars, especially in Asian populations. OBJECTIVE Evaluating the efficacy of diffractive lens 755-nm picosecond
Ching-Hsin Huang +3 more
semanticscholar +1 more source
Understanding the Diffractive Bifocal Contact Lens
Optometry and Vision Science, 1993How a diffractive bifocal contact lens works is not intuitively obvious. This is because the diffractive bifocal operates by an unusual blend of refraction and interference. The present article seeks to clarify how it achieves its two focal powers. Most of this article, however, is devoted to the conceptually simpler case of diffraction gratings in ...
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Journal of Optics, 1994
In the paper diffraction theory is applied to obtain the field received by an aperture in the parallel-plate region of a Rotman lens when the outer arc of the lens is excited with arbitrary phase and amplitude distributions. It has been found that the receiving aperture does not detect the maximum power when it is located upon the nominal focus, it is ...
J L Cruz, B Gimeno, E A Navarro, V Such
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In the paper diffraction theory is applied to obtain the field received by an aperture in the parallel-plate region of a Rotman lens when the outer arc of the lens is excited with arbitrary phase and amplitude distributions. It has been found that the receiving aperture does not detect the maximum power when it is located upon the nominal focus, it is ...
J L Cruz, B Gimeno, E A Navarro, V Such
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Diffractive multifocal intraocular lens image quality
Applied Optics, 1992The diffractive multifocal intraocular lens is implanted in the eye to replace a cataractous crystalline lens. Axially separated images from two diffraction orders provide near and distance vision. Overall image quality is affected by both the quality of the in-focus component and the energy distribution between images. Modulation transfer function and
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Journal of cataract and refractive surgery, 2018
PURPOSE To compare the visual outcomes of 2 diffractive intraocular lenses (IOLs), a panfocal model and a trifocal model, after femtosecond laser-assisted lens surgery.
Myriam Böhm +6 more
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PURPOSE To compare the visual outcomes of 2 diffractive intraocular lenses (IOLs), a panfocal model and a trifocal model, after femtosecond laser-assisted lens surgery.
Myriam Böhm +6 more
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Hybrid refractive-diffractive superachromatic lens
Annual Meeting Optical Society of America, 1989The design, manufacture, and applications over wide spectral bands of hybrid refractive-diffractive lenses have been addressed recently by several authors.1,2 Although it is fairly easy to design an achromatic hybrid lens, its optical performance is often limited by secondary color and spherochromatism.
R. I. Mercado, L. D. Foo, S. P. Clark
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High-efficiency switchable diffractive lens
SPIE Proceedings, 2006We demonstrate that, by using circular array of electrode pattern and applying multi-level phase modulation in each zone, a high-efficiency switchable electro-optic diffractive lens using liquid crystal as the active medium can be produced as a switchable eyewear. The lens is flat and the thickness of the liquid crystal is 5 μm.
Guoqiang Li +10 more
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Diffractive optics: the gradial zone lens
Optics Letters, 1994A gradial zone lens has the diffractive component within the bulk lens rather than as a surface-relief profile. It is constructed by spin molding annular zones from microliter volumes of monomers injected into a rotating mold. Plastic lenses have micrometer width zones with dimensions that give a phase difference of modulo 2pi. A gradial lens made with
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