enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. 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 ...

  3. Köhler illumination - Wikipedia

    en.wikipedia.org/wiki/Köhler_illumination

    Köhler illumination is a method of specimen illumination used for transmitted and reflected light (trans- and epi-illuminated) optical microscopy.Köhler illumination acts to generate an even illumination of the sample and ensures that an image of the illumination source (for example a halogen lamp filament) is not visible in the resulting image.

  4. Optical transfer function - Wikipedia

    en.wikipedia.org/wiki/Optical_transfer_function

    As an example, the figure on the right shows the 3D point-spread function in object space of a wide-field microscope (a) alongside that of a confocal microscope (c). Although the same microscope objective with a numerical aperture of 1.49 is used, it is clear that the confocal point spread function is more compact both in the lateral dimensions ...

  5. Oil immersion - Wikipedia

    en.wikipedia.org/wiki/Oil_immersion

    where α 0 is half the angle spanned by the objective lens seen from the sample, and n is the refractive index of the medium between the lens and specimen (≈1 for air). State-of-the-art objectives can have numerical apertures of up to 0.95. Because sin α 0 ≤ 1, the numerical aperture can never be greater than unity for an objective lens in ...

  6. Light sheet fluorescence microscopy - Wikipedia

    en.wikipedia.org/wiki/Light_sheet_fluorescence...

    Most light sheet fluorescence microscopes are used to produce 3D images of the sample by moving the sample through the image plane. If the sample is larger than the field of view of the image sensor, the sample also has to be shifted laterally. An alternative approach is to move the image plane through the sample to create the image stack. [32]

  7. Exit pupil - Wikipedia

    en.wikipedia.org/wiki/Exit_pupil

    In optics, the exit pupil is a virtual aperture in an optical system. Only rays which pass through this virtual aperture can exit the system. The exit pupil is the image of the aperture stop in the optics that follow it. In a telescope or compound microscope, this image is the image of the objective element(s) as produced by the eyepiece. The ...

  8. Optical aberration - Wikipedia

    en.wikipedia.org/wiki/Optical_aberration

    Each of the four coordinates ξ', η', x', y' are functions of ξ, η, x, y; and if it be assumed that the field of view and the aperture be infinitely small, then ξ, η, x, y are of the same order of infinitesimals; consequently by expanding ξ', η', x', y' in ascending powers of ξ, η, x, y, series are obtained in which it is only ...

  9. Optical sectioning - Wikipedia

    en.wikipedia.org/wiki/Optical_sectioning

    With no modification to the microscope, i.e. with a simple wide field light microscope, the quality of optical sectioning is governed by the same physics as the depth of field effect in photography. For a high numerical aperture lens, equivalent to a wide aperture, the depth of field is small (shallow focus) and gives