enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Abbe number - Wikipedia

    en.wikipedia.org/wiki/Abbe_number

    Abbe number. In optics and lens design, the Abbe number, also known as the V-number or constringence of a transparent material, is an approximate measure of the material's dispersion (change of refractive index versus wavelength), with high values of V indicating low dispersion. It is named after Ernst Abbe (1840–1905), the German physicist ...

  3. Diffraction-limited system - Wikipedia

    en.wikipedia.org/wiki/Diffraction-limited_system

    An optical instrument is said to be diffraction-limited if it has reached this limit of resolution performance. Other factors may affect an optical system's performance, such as lens imperfections or aberrations, but these are caused by errors in the manufacture or calculation of a lens, whereas the diffraction limit is the maximum resolution ...

  4. Corrective lens - Wikipedia

    en.wikipedia.org/wiki/Corrective_lens

    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.

  5. Chromatic aberration - Wikipedia

    en.wikipedia.org/wiki/Chromatic_aberration

    Chromatic aberration. Focal length of lens varies with the color of light. In optics, chromatic aberration ( CA ), also called chromatic distortion, color aberration, color fringing, or purple fringing, is a failure of a lens to focus all colors to the same point. [ 1][ 2] It is caused by dispersion: the refractive index of the lens elements ...

  6. Abbe sine condition - Wikipedia

    en.wikipedia.org/wiki/Abbe_sine_condition

    In optics, the Abbe sine condition is a condition that must be fulfilled by a lens or other optical system in order for it to produce sharp images of off-axis as well as on-axis objects. It was formulated by Ernst Abbe in the context of microscopes. [ 1] The Abbe sine condition says that. the sine of the object-space angle should be ...

  7. Optical transfer function - Wikipedia

    en.wikipedia.org/wiki/Optical_transfer_function

    The line-spread function is directly proportional to the vertical integration of the point-spread image. The optical-transfer function (OTF) is defined as the Fourier transform of the point-spread function and is thus generally a two-dimensional complex function. Typically only a one-dimensional slice is shown (c), corresponding to the Fourier ...

  8. Numerical aperture - Wikipedia

    en.wikipedia.org/wiki/Numerical_aperture

    In microscopy, NA is important because it indicates the resolving power of a lens. The size of the finest detail that can be resolved (the resolution) is proportional to ⁠ λ / 2NA ⁠, where λ is the wavelength of the light. A lens with a larger numerical aperture will be able to visualize finer details than a lens with a smaller numerical ...

  9. AOL Mail

    mail.aol.com/?rp=webmail-std/en-us/basic

    Absolutely! It's quick and easy to sign up for a free AOL account. With your AOL account you get features like AOL Mail, news, and weather for free!