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  2. Microscopy with UV surface excitation - Wikipedia

    en.wikipedia.org/wiki/Microscopy_with_UV_surface...

    The microscope setup is based on an inverted microscope design. [ 2 ] [ 3 ] [ 4 ] An automated stage is used to record larger areas by mosaicing a series of single adjacent frames. The LED light is focused using a ball lens with a short focal length onto the sample surface in an oblique-angle cis-illumination scheme since standard microscopy ...

  3. 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).

  4. UV detectors - Wikipedia

    en.wikipedia.org/wiki/UV_detectors

    As can be seen in Figure 1, these detectors have a light source, a dispersion element that is a diffraction grating or prism, a flow cell, to where the sample arrives directly from the chromatographic column, an optical bench of lenses and mirrors, and a diode that receives the light coming from the optical system and translates it into a ...

  5. Ultraviolet–visible spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet–visible...

    A UV-Vis spectrophotometer is an analytical instrument that measures the amount of ultraviolet (UV) and visible light that is absorbed by a sample. It is a widely used technique in chemistry, biochemistry, and other fields, to identify and quantify compounds in a variety of samples.

  6. Dispersion staining - Wikipedia

    en.wikipedia.org/wiki/Dispersion_staining

    If the particle has a higher refractive index than the liquid surrounding it then it behaves as a convex lens and focuses a parallel beam of light on the side opposite the source of the light. Looking through the microscope this is seen as a bright ring of light, the Becke` Line, moving in from the edge as the particle is dropped out of focus ...

  7. Microscopy - Wikipedia

    en.wikipedia.org/wiki/Microscopy

    A two-photon microscope is also a laser-scanning microscope, but instead of UV, blue or green laser light, a pulsed infrared laser is used for excitation. Only in the tiny focus of the laser is the intensity high enough to generate fluorescence by two-photon excitation , which means that no out-of-focus fluorescence is generated, and no pinhole ...

  8. 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.

  9. Newton's rings - Wikipedia

    en.wikipedia.org/wiki/Newton's_rings

    Newton's rings observed through a microscope. The smallest increments on the superimposed scale are 100 μm. The illumination is from below, leading to a bright central region. Newton's rings interference pattern created by a plano-convex lens illuminated by 650 nm red laser light, photographed using a low-light microscope. The illumination is ...