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  2. Dispersive prism - Wikipedia

    en.wikipedia.org/wiki/Dispersive_prism

    Crown glasses such as BK7 have a relatively small dispersion (and can be used roughly between 330 and 2500 nm), while flint glasses have a much stronger dispersion for visible light and hence are more suitable for use as dispersive prisms, but their absorption sets on already around 390 nm.

  3. Prism (optics) - Wikipedia

    en.wikipedia.org/wiki/Prism_(optics)

    Not all optical prisms are geometric prisms, and not all geometric prisms would count as an optical prism. Prisms can be made from any material that is transparent to the wavelengths for which they are designed. Typical materials include glass, acrylic and fluorite .

  4. Optical coating - Wikipedia

    en.wikipedia.org/wiki/Optical_coating

    Optical coating. An optical coating is one or more thin layers of material deposited on an optical component such as a lens, prism or mirror, which alters the way in which the optic reflects and transmits light. These coatings have become a key technology in the field of optics. One type of optical coating is an anti-reflective coating, which ...

  5. Prism correction - Wikipedia

    en.wikipedia.org/wiki/Prism_correction

    Prism correction. Prism lenses (here unusually thick) are used for pre-operative prism adaptation. Eye care professionals use prism correction as a component of some eyeglass prescriptions. A lens which includes some amount of prism correction will displace the viewed image horizontally, vertically, or a combination of both directions.

  6. Lens - Wikipedia

    en.wikipedia.org/wiki/Lens

    A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses ( elements ), usually arranged along a common axis. Lenses are made from materials such as glass or plastic and are ground, polished, or molded to the required shape. A ...

  7. Optical glass - Wikipedia

    en.wikipedia.org/wiki/Optical_glass

    Optical glass refers to a quality of glass suitable for the manufacture of optical systems such as optical lenses, prisms or mirrors. Unlike window glass or crystal, whose formula is adapted to the desired aesthetic effect, optical glass contains additives designed to modify certain optical or mechanical properties of the glass: refractive index, dispersion, transmittance, thermal expansion ...

  8. Corrective lens - Wikipedia

    en.wikipedia.org/wiki/Corrective_lens

    A corrective lens is a transmissive optical device that is worn on the eye to improve visual perception. The most common use is to treat refractive errors: myopia, hypermetropia, astigmatism, and presbyopia. Glasses or "spectacles" are worn on the face a short distance in front of the eye. Contact lenses are worn directly on the surface of the eye. Intraocular lenses are surgically implanted ...

  9. Progressive lens - Wikipedia

    en.wikipedia.org/wiki/Progressive_lens

    Progressive lenses are corrective lenses used in eyeglasses to correct presbyopia and other disorders of accommodation. They are characterised by a gradient of increasing lens power, added to the wearer's correction for the other refractive errors. The gradient starts at the wearer's distance prescription at the top of the lens and reaches a ...

  10. Chromatic aberration - Wikipedia

    en.wikipedia.org/wiki/Chromatic_aberration

    In optics, chromatic aberration ( CA ), also called chromatic distortion and spherochromatism, is a failure of a lens to focus all colors to the same point. [1] It is caused by dispersion: the refractive index of the lens elements varies with the wavelength of light. The refractive index of most transparent materials decreases with increasing wavelength. [2] Since the focal length of a lens ...

  11. Polarizer - Wikipedia

    en.wikipedia.org/wiki/Polarizer

    The Sénarmont prism is air spaced, unlike the Wollaston and Rochon prisms. These prisms truly split the beam into two fully polarized beams with perpendicular polarizations. The Nomarski prism is a variant of the Wollaston prism, which is widely used in differential interference contrast microscopy .