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  2. Depth of field - Wikipedia

    en.wikipedia.org/wiki/Depth_of_field

    As distance or the size of the acceptable circle of confusion increases, the depth of field increases; however, increasing the size of the aperture (i.e., reducing f-number) or increasing the focal length reduces the depth of field. Depth of field changes linearly with f-number and circle of confusion, but changes in proportion to the square of ...

  3. Numerical aperture - Wikipedia

    en.wikipedia.org/wiki/Numerical_aperture

    As a pencil of light goes through a flat plane of glass, its half-angle changes to θ 2. 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 ...

  4. Aperture - Wikipedia

    en.wikipedia.org/wiki/Aperture

    Reducing the aperture size (increasing the f-number) provides less light to sensor and also increases the depth of field (by limiting the angle of cone of image light reaching the sensor), which describes the extent to which subject matter lying closer than or farther from the actual plane of focus appears to be in focus. In general, the ...

  5. 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

  6. Diffraction-limited system - Wikipedia

    en.wikipedia.org/wiki/Diffraction-limited_system

    Memorial in Jena, Germany to Ernst Karl Abbe, who approximated the diffraction limit of a microscope as = ⁡, where d is the resolvable feature size, λ is the wavelength of light, n is the index of refraction of the medium being imaged in, and θ (depicted as α in the inscription) is the half-angle subtended by the optical objective lens (representing the numerical aperture).

  7. Oil immersion - Wikipedia

    en.wikipedia.org/wiki/Oil_immersion

    In light microscopy, oil immersion is a technique used to increase the resolving power of a microscope. This is achieved by immersing both the objective lens and the specimen in a transparent oil of high refractive index , thereby increasing the numerical aperture of the objective lens.

  8. 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 ...

  9. Light field microscopy - Wikipedia

    en.wikipedia.org/wiki/Light_field_microscopy

    Light field microscopy (LFM) is a scanning-free 3-dimensional (3D) microscopic imaging method based on the theory of light field.This technique allows sub-second (~10 Hz) large volumetric imaging ([~0.1 to 1 mm] 3) with ~1 μm spatial resolution in the condition of weak scattering and semi-transparence, which has never been achieved by other methods.