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  2. Fresnel lens - Wikipedia

    en.wikipedia.org/wiki/Fresnel_lens

    The Fresnel lens reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections. An ideal Fresnel lens would have an infinite number of sections. In each section, the overall thickness is decreased compared to an equivalent simple lens.

  3. Fresnel number - Wikipedia

    en.wikipedia.org/wiki/Fresnel_number

    The Fresnel number is a useful concept in physical optics. The Fresnel number establishes a coarse criterion to define the near and far field approximations. Essentially, if Fresnel number is small – less than roughly 1 – the beam is said to be in the far field. If Fresnel number is larger than 1, the beam is said to be near field.

  4. Biology in fiction - Wikipedia

    en.wikipedia.org/wiki/Biology_in_fiction

    Boris Karloff in James Whale's 1931 film Frankenstein, based on Mary Shelley's 1818 novel.The monster is created by an unorthodox biology experiment.. Biology appears in fiction, especially but not only in science fiction, both in the shape of real aspects of the science, used as themes or plot devices, and in the form of fictional elements, whether fictional extensions or applications of ...

  5. Fresnel diffraction - Wikipedia

    en.wikipedia.org/wiki/Fresnel_diffraction

    Fresnel diffraction of circular aperture, plotted with Lommel functions. This is the Fresnel diffraction integral; it means that, if the Fresnel approximation is valid, the propagating field is a spherical wave, originating at the aperture and moving along z. The integral modulates the amplitude and phase of the spherical wave.

  6. Fresnel equations - Wikipedia

    en.wikipedia.org/wiki/Fresnel_equations

    Fresnel equations. Partial transmission and reflection of a pulse travelling from a low to a high refractive index medium. At near-grazing incidence, media interfaces appear mirror-like especially due to reflection of the s polarization, despite being poor reflectors at normal incidence. Polarized sunglasses block the s polarization, greatly ...

  7. Fresnel integral - Wikipedia

    en.wikipedia.org/wiki/Fresnel_integral

    The sector contour used to calculate the limits of the Fresnel integrals. This can be derived with any one of several methods. One of them [5] uses a contour integral of the function around the boundary of the sector-shaped region in the complex plane formed by the positive x-axis, the bisector of the first quadrant y = x with x ≥ 0, and a circular arc of radius R centered at the origin.

  8. Catadioptric system - Wikipedia

    en.wikipedia.org/wiki/Catadioptric_system

    A catadioptric optical system is one where refraction and reflection are combined in an optical system, usually via lenses ( dioptrics) and curved mirrors ( catoptrics ). Catadioptric combinations are used in focusing systems such as searchlights, headlamps, early lighthouse focusing systems, optical telescopes, microscopes, and telephoto lenses.

  9. The 50 Best Science Fiction Books to Give You the ... - AOL

    www.aol.com/40-best-science-fiction-books...

    Dune by Frank Herbert. Dune is epic sci-fi. Operatic sci-fi. It’s the sci-fi of world (nay, universe) building, and in that sense it shares much with the fantasy genre—those works inspired by ...