Results 201 to 210 of about 6,788 (257)
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Focusing by a high-power, low-Fresnel-number lens: the fly facet lens
Journal of the Optical Society of America A, 1991Diffraction by fly facet lenses has been investigated by photographing the diffraction patterns at various distances from a facet lens whose power was estimated to be 2.03 x 10(4) D. We studied three different aperture diameters with Fresnel numbers of the order of unity. A large focal shift was prominent at the lower Fresnel number.
Stavenga, D.G., Hateren, J.H. van
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Narrowing effect of focused polychromatic laser with small Fresnel number
Optics Communications, 2011Abstract Starting from Huygens–Fresnel diffraction integral, the field representation of focused polychromatic laser beams is derived. Intensity distributions of the focused polychromatic laser are investigated with different Fresnel number and bandwidth at focal plane.
Runwu Peng +4 more
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Structure of focused fields in systems with large Fresnel numbers
Journal of the Optical Society of America A, 1995A new and simple formula valid within the framework of the Debye theory is derived for determining the structure of focused fields in diffraction-limited systems. It is first applied to study the field behavior in the focal region, and the results are compared with those of the classic theory of Lommel.
Weijian Wang, Ari T. Friberg, Emil Wolf
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The Fabry‐Perot Interferometer with a Large Fresnel Number
Annalen der Physik, 1965AbstractThe Fabry‐Perot Interferometer is investigated on the basis of the Huygens‐Fresnel Principle. An integral equation is derived which describes its features when used as a laser resonator. An asymptotic expansion is given for a large Fresnel Number. The first‐order approximation describes the waves resonating between the mirrors.
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Imaging at low Fresnel number: some challenges and applications
SPIE Proceedings, 2006A brief review of the main effects associated with low Fresnel number N in optical system with circular and elliptical pupil shape under uniform and Gaussian illumination is given. The attention is drawn more specifically on the focal shift and its impact on static resolution and depth-of-focus.
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Effective Fresnel number and the focal shifts of focused partially coherent beams
Journal of the Optical Society of America A, 2007We define the effective Fresnel number of the cylindrical lens illuminated by a plane wave or Schell-model beams. On the basis of the concept of the effective Fresnel number, the focusing properties of the cylindrical lens illuminated by the Schell-model beam are investigated in a simple way.
Meimei, Dong, Jixiong, Pu
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Fresnel's original interpretation of complex numbers in 19th century optics
American Journal of Physics, 2018In 1823, Fresnel published an original (physical) interpretation of complex numbers in his investigations of refraction and reflection of polarized light. This is arguably the first time that complex numbers were given a physical interpretation, which led to a better understanding of elliptical and circular polarizations. This rather unknown episode of
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Cancer treatment and survivorship statistics, 2022
Ca-A Cancer Journal for Clinicians, 2022Kimberly D Miller +2 more
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Fourier ptychographic microscopy using Fresnel propagation with reduced number of images
, 2020 Mojde Hasanzade +4 more
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Imaging properties of an extreme ultraviolet microscope objective with reduced Fresnel number
, 2017 Mitsunori Toyoda +2 more
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