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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 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 ...

  4. Zone plate - Wikipedia

    en.wikipedia.org/wiki/Zone_plate

    A zone plate is a device used to focus light or other things exhibiting wave character. [ 1] Unlike lenses or curved mirrors, zone plates use diffraction instead of refraction or reflection. Based on analysis by French physicist Augustin-Jean Fresnel, they are sometimes called Fresnel zone plates in his honor.

  5. Optical landing system - Wikipedia

    en.wikipedia.org/wiki/Optical_landing_system

    Optical landing system. The fresnel lens optical landing system of Charles de Gaulle. An optical landing system ( OLS) (nicknamed "meatball" or simply "ball") is used to give glidepath information to pilots in the terminal phase of landing on an aircraft carrier. [ 1]

  6. Overhead projector - Wikipedia

    en.wikipedia.org/wiki/Overhead_projector

    Overhead projector. An overhead projector (often abbreviated to OHP ), like a film or slide projector, uses light to project an enlarged image on a screen, allowing the view of a small document or picture to be shared with a large audience. In the overhead projector, the source of the image is a page-sized sheet of transparent plastic film ...

  7. Magnifying glass - Wikipedia

    en.wikipedia.org/wiki/Magnifying_glass

    A magnifying glass is a convex lens that is used to produce a magnified image of an object. The lens is usually mounted in a frame with a handle. Beyond its primary function of magnification, this simple yet ingenious tool serves a variety of purposes. It can be employed to focus sunlight, harnessing the Sun's rays to create a concentrated hot ...

  8. Traffic light - Wikipedia

    en.wikipedia.org/wiki/Traffic_light

    The Fresnel lens collimates the light output created by the lamp and creates a uniform display of light for the lane in which it is intended. In addition to being positioned and mounted for desired visibility for their respective traffic, some traffic lights are also aimed, louvered, or shaded to minimize misinterpretation from other lanes.

  9. 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.