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. Template:Pentax K-mount lens compatibility chart - Wikipedia

    en.wikipedia.org/wiki/Template:Pentax_K-mount...

    lens function compatibility. KAF2 digital SDM without aperture simulator and with ED-interface: K-70. After update of firmware: K-50, K-1, K-3, K-3II, K-S2, K-S1. 2 – K10D can be updated to change from Powerzoom-use to SDM-drive. On cameras with K AF /K AF2 -mount without aperture simulator during Av metering the aperture has to be adjusted ...

  5. 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.

  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. 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 ...

  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. List of Pentax products - Wikipedia

    en.wikipedia.org/wiki/List_of_Pentax_products

    A sixth lens and an adapter were announced in September, 2012. Pentax 01 Standard Prime (2011) — 47 mm equivalent; Pentax 02 Standard Zoom (2011) — 28–80 mm equivalent; Pentax 03 Fisheye (2011) — 17.5 mm equivalent; Pentax 04 Toy Lens Wide (2011) — 35 mm equivalent; Pentax 05 Toy Lens Telephoto (2011) — 100 mm equivalent