enow.com Web Search

  1. Ad

    related to: how to measure fresnel prism area

Search results

  1. Results from the WOW.Com Content Network
  2. Fresnel equations - Wikipedia

    en.wikipedia.org/wiki/Fresnel_equations

    Since the Fresnel equations were developed for optics, they are usually given for non-magnetic materials. Dividing ( 4) by ( 5 )) yields. For non-magnetic media we can substitute the vacuum permeability μ0 for μ, so that that is, the admittances are simply proportional to the corresponding refractive indices.

  3. Fresnel lens - Wikipedia

    en.wikipedia.org/wiki/Fresnel_lens

    A Fresnel lens ( / ˈfreɪnɛl, - nəl / FRAY-nel, -⁠nəl; / ˈfrɛnɛl, - əl / FREN-el, -⁠əl; or / freɪˈnɛl / fray-NEL [1]) is a type of composite compact lens which reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections.

  4. Fresnel rhomb - Wikipedia

    en.wikipedia.org/wiki/Fresnel_rhomb

    A Fresnel rhomb is an optical prism that introduces a 90° phase difference between two perpendicular components of polarization, by means of two total internal reflections. If the incident beam is linearly polarized at 45° to the plane of incidence and reflection, the emerging beam is circularly polarized , and vice versa.

  5. Surface plasmon resonance - Wikipedia

    en.wikipedia.org/wiki/Surface_plasmon_resonance

    Surface plasmon resonance ( SPR) is a phenomenon that occurs where electrons in a thin metal sheet become excited by light that is directed to the sheet with a particular angle of incidence, and then travel parallel to the sheet. Assuming a constant light source wavelength and that the metal sheet is thin, the angle of incidence that triggers ...

  6. Fresnel number - Wikipedia

    en.wikipedia.org/wiki/Fresnel_number

    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. Essentially, if Fresnel number is small – less than roughly 1 – the beam is said to be in the far field.

  7. Fresnel zone - Wikipedia

    en.wikipedia.org/wiki/Fresnel_zone

    Fresnel zone: D is the distance between the transmitter and the receiver; r is the radius of the first Fresnel zone (n=1) at point P. P is d1 away from the transmitter, and d2 away from the receiver. The concept of Fresnel zone clearance may be used to analyze interference by obstacles near the path of a radio beam. The first zone must be kept ...

  8. Snell's law - Wikipedia

    en.wikipedia.org/wiki/Snell's_law

    Snell's law. Refraction of light at the interface between two media of different refractive indices, with n 2 > n 1. Since the velocity is lower in the second medium (v 2 < v 1 ), the angle of refraction θ 2 is less than the angle of incidence θ 1; that is, the ray in the higher-index medium is closer to the normal.

  9. Interferometry - Wikipedia

    en.wikipedia.org/wiki/Interferometry

    Figure 1. The light path through a Michelson interferometer.The two light rays with a common source combine at the half-silvered mirror to reach the detector. They may either interfere constructively (strengthening in intensity) if their light waves arrive in phase, or interfere destructively (weakening in intensity) if they arrive out of phase, depending on the exact distances between the ...

  10. Four prism dioptre reflex test - Wikipedia

    en.wikipedia.org/wiki/Four_prism_dioptre_reflex_test

    The Four Prism Dioptre Reflex Test (also known as the 4 PRT, or 4 Prism Dioptre Base-out Test) is an objective, non-dissociative test used to prove the alignment of both eyes (i.e. the presence of binocular single vision) by assessing motor fusion.

  11. Fresnel integral - Wikipedia

    en.wikipedia.org/wiki/Fresnel_integral

    From the definitions of Fresnel integrals, the infinitesimals dx and dy are thus: d x = C ′ ( t ) d t = cos ⁡ ( t 2 ) d t , d y = S ′ ( t ) d t = sin ⁡ ( t 2 ) d t . {\displaystyle {\begin{aligned}dx&=C'(t)\,dt=\cos \left(t^{2}\right)\,dt,\\dy&=S'(t)\,dt=\sin \left(t^{2}\right)\,dt.\end{aligned}}}