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Wave-front analysis using Fresnel lens arrays
Optics Letters, 1995A compact wave-front sensor is implemented by an array of two-beam common path inversion interferometers. Each element of the array consists of two Fresnel lenses in a confocal configuration. The wave-front data can be extracted from a superposition of the zero-order undiffracted wave and the twice-diffracted first-order wave.
B, Spektor, J, Shamir
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SPIE Proceedings, 1985
A description is given of the use of the Fresnel zone plate as a focusing or a frequency-filtering device at millimeter wavelengths. Sample design data are given, as well as references to prior results. A newer type of zone plate is discussed which employs two dielectrics of equal thickness to produce a flat zone plate.
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A description is given of the use of the Fresnel zone plate as a focusing or a frequency-filtering device at millimeter wavelengths. Sample design data are given, as well as references to prior results. A newer type of zone plate is discussed which employs two dielectrics of equal thickness to produce a flat zone plate.
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Switchable Fresnel lens based on micropatterned alignment
Optics Letters, 2013In this Letter we disclose a method to fabricate a liquid crystal (LC) Fresnel zone lens (FZL) with higher efficiency. The LCFZL, based on alternate twisted nematic (TN) and planar aligned (PA) regions, has been prepared by means of a two-step photo-alignment process.
Wang, Xiaoqian +3 more
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Nine-sector three-stage Fresnel lens concentrator
Applied Optics, 2018In this paper, we design a three-stage Fresnel lens concentrator with a low f number. The proposed concentrator consists of a primary optical element (POE) and a second optical element (SOE). The nine-sector three-stage Fresnel lens is composed of three types of triangular prisms: the refractive triangular prism, single total internal reflection ...
Yong-Da, Chen +4 more
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International Journal of Ambient Energy, 2019
The shortage of drinking water has become one of the biggest problems in the world. Water pollution has increased considerably because of factors such as population growth, industrialisation and urbanisation.
V. Sriram +6 more
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The shortage of drinking water has become one of the biggest problems in the world. Water pollution has increased considerably because of factors such as population growth, industrialisation and urbanisation.
V. Sriram +6 more
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Reflections from a Fresnel lens
Physics Education, 2004Reflection of light by a convex Fresnel lens gives rise to two distinct images. A highly convex inverted real reflective image forms on the object side of the lens, while an upright virtual reflective image forms on the opposite side of the lens. I describe here a set of laser experiments performed upon a Fresnel lens.
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ZnS micro-Fresnel lens and its uses
Applied Optics, 1990A micro-Fresnel lens replication method by inorganic material deposition has been developed. A ZnS micro-Fresnel lens and a completely flat micro-Fresnel lens have been made by this method. The ZnS microFresnel lens stability characteristics are improved for temperature, humidity, and focusing.
H, Hosokawa, T, Yamashita
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Fresnel lens analysis for solar energy applications
Applied Optics, 1981In this paper we analyze an arbitrarily shaped lineal Fresnel lens acting either as sole concentration stage or as the first stage of a two-stage concentration system in which the second stage considers the first as a Lambertian source. We determine the gain and position of the lens for all possible configurations, and we demonstrate that a curved lens
E, Lorenzo, A, Luque
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