enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Speckle (interference) - Wikipedia

    en.wikipedia.org/wiki/Speckle_(interference)

    Speckle imaging and eye testing using speckle also use the speckle effect. Speckle is the chief limitation of coherent lidar and coherent imaging in optical heterodyne detection. In the case of near field speckles, the statistical properties depend on the light scattering distribution of a given sample.

  3. Electronic speckle pattern interferometry - Wikipedia

    en.wikipedia.org/wiki/Electronic_speckle_pattern...

    Electronic speckle pattern interferometry (ESPI), [1] also known as TV holography, is a technique that uses laser light, together with video detection, recording and processing, to visualise static and dynamic displacements of components with optically rough surfaces. The visualisation is in the form of fringes on the image, where each fringe ...

  4. Laser speckle contrast imaging - Wikipedia

    en.wikipedia.org/wiki/Laser_speckle_contrast_imaging

    The size of each speckle pattern should smaller than the photodetector's pixel size to avoid the decrease of contrast. The minimum speckle diameter for an LSCI system depends on the wavelength of light, imaging system magnification, and imaging system f-number: d min ≈ 1.2 ( 1 + M ) λ f / # {\displaystyle d_{\min }\thickapprox 1.2(1+M ...

  5. Electro-optics - Wikipedia

    en.wikipedia.org/wiki/Electro-optics

    Electro–optics is a branch of electrical engineering, electronic engineering, materials science, and material physics involving components, electronic devices such as lasers, laser diodes, LEDs, waveguides, etc. which operate by the propagation and interaction of light with various tailored materials.

  6. Speckle variance optical coherence tomography - Wikipedia

    en.wikipedia.org/wiki/Speckle_variance_optical...

    Optical coherence tomography is an imaging modality that uses low-coherence interferometry to obtain high resolution, depth-resolved volumetric images. OCT can be used to capture functional images of blood flow, a technique known as optical coherence tomography angiography (OCT-A). SV-OCT is one method for OCT-A that uses the variance of ...

  7. Dynamic speckle - Wikipedia

    en.wikipedia.org/wiki/Dynamic_speckle

    Figure 1 shows a sequence of speckle patterns in a corn seed in the start of its germination process where the dynamic effect is higher in the areas where the scattering centers are expected to be more active as is the case of the embryo and in a break in the endosperm region of the seed. The embryo is in the lower left side and the break is a ...

  8. Optoelectronics - Wikipedia

    en.wikipedia.org/wiki/Optoelectronics

    Optoelectronics (or optronics) is the study and application of electronic devices and systems that find, detect and control light, usually considered a sub-field of photonics. In this context, light often includes invisible forms of radiation such as gamma rays , X-rays , ultraviolet and infrared , in addition to visible light.

  9. Eye testing using speckle - Wikipedia

    en.wikipedia.org/wiki/Eye_testing_using_speckle

    When a surface is illuminated by a laser beam and is viewed by an observer, a speckle pattern is formed on the retina. [ 2 ] [ 3 ] If the observer has perfect vision, the image of the surface is also formed on the retina, and movement of the head will result in the speckle pattern and the surface moving together so that the speckle pattern ...