enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Numerical aperture - Wikipedia

    en.wikipedia.org/wiki/Numerical_aperture

    Due to Snell's law, the numerical aperture remains the same: NA = n 1 sin θ 1 = n 2 sin θ 2. In optics, the numerical aperture (NA) of an optical system is a dimensionless number that characterizes the range of angles over which the system can accept or emit light.

  3. f-number - Wikipedia

    en.wikipedia.org/wiki/F-number

    A lower f-number means a larger relative aperture and more light entering the system, while a higher f-number means a smaller relative aperture and less light entering the system. The f-number is related to the numerical aperture (NA) of the system, which measures the range of angles over which light can enter or exit the system.

  4. Angular aperture - Wikipedia

    en.wikipedia.org/wiki/Angular_aperture

    The angular aperture of a thin lens with focal point at F and an aperture of diameter . The angular aperture of a lens is the angular size of the lens aperture as seen from the focal point: = ⁡ (/) = ⁡ where

  5. Airy disk - Wikipedia

    en.wikipedia.org/wiki/Airy_disk

    A real Airy disk created by passing a red laser beam through a 90-micrometre pinhole aperture with 27 orders of diffraction Airy disk captured by 2000 mm camera lens at f/25 aperture. Image size: 1×1 mm. In optics, the Airy disk (or Airy disc) and Airy pattern are descriptions of the best-focused spot of light that a perfect lens with a ...

  6. Fresnel number - Wikipedia

    en.wikipedia.org/wiki/Fresnel_number

    Aperture real amplitude as estimated at focus of a half inch perfect lens having Fresnel number equal to 0.01. Adopted wavelength for propagation is 1 μm. 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.

  7. Angular resolution - Wikipedia

    en.wikipedia.org/wiki/Angular_resolution

    where θ is the angular resolution , λ is the wavelength of light, and D is the diameter of the lens' aperture. The factor 1.22 is derived from a calculation of the position of the first dark circular ring surrounding the central Airy disc of the diffraction pattern. This number is more precisely 1.21966989...

  8. Aperture - Wikipedia

    en.wikipedia.org/wiki/Aperture

    In digital photography, the 35mm-equivalent aperture range is sometimes considered to be more important than the actual f-number. Equivalent aperture is the f-number adjusted to correspond to the f-number of the same size absolute aperture diameter on a lens with a 35mm equivalent focal length. Smaller equivalent f-numbers are expected to lead ...

  9. Pupil function - Wikipedia

    en.wikipedia.org/wiki/Pupil_function

    The pupil function or aperture function describes how a light wave is affected upon transmission through an optical imaging system such as a camera, microscope, or the human eye. More specifically, it is a complex function of the position in the pupil [ 1 ] or aperture (often an iris ) that indicates the relative change in amplitude and phase ...