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  2. Prism correction - Wikipedia

    en.wikipedia.org/wiki/Prism_correction

    Prentice's rule, named so after the optician Charles F. Prentice, is a formula used to determine the amount of induced prism in a lens: = where: P is the amount of prism correction (in prism dioptres) c is decentration (the distance between the pupil centre and the lens's optical centre, in millimetres)

  3. Esophoria - Wikipedia

    en.wikipedia.org/wiki/Esophoria

    Esophoria is an eye condition involving inward deviation of the eye, usually due to extra-ocular muscle imbalance. It is a type of heterophoria. Cause. Causes include: Refractive errors; Divergence insufficiency; Convergence excess; this can be due to nerve, muscle, congenital or mechanical anomalies.

  4. Eötvös effect - Wikipedia

    en.wikipedia.org/wiki/Eötvös_effect

    The force of gravity and the normal force. The resultant force acts as the required centripetal force. The mathematical derivation for the Eötvös effect for motion along the Equator explains the factor 2 in the first term of the Eötvös correction formula. What remains to be explained is the cosine factor.

  5. Free-air gravity anomaly - Wikipedia

    en.wikipedia.org/wiki/Free-air_gravity_anomaly

    The free-air correction is the amount that must be added to a measurement at height to correct it to the reference level: δ g F = 2 g R × h {\displaystyle \delta g_{F}={\frac {2g}{R}}\times h} Here we have assumed that measurements are made relatively close to the surface so that R does not vary significantly.

  6. Anisometropia - Wikipedia

    en.wikipedia.org/wiki/Anisometropia

    Amblyopia. Anisometropia is a condition in which a person's eyes have substantially differing refractive power. [1] Generally, a difference in power of one diopter (1D) is the threshold for diagnosis of the condition . [2] [3] Patients may have up to 3D of anisometropia before the condition becomes clinically significant due to headache, eye ...

  7. 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.

  8. Bolometric correction - Wikipedia

    en.wikipedia.org/wiki/Bolometric_correction

    Mathematically, such a calculation could be expressed: B C K = M bol − M k {\displaystyle BC_{K}=M_{\text{bol}}-M_{k}} Where M K is the absolute magnitude value and BC K is the bolometric correction value in the K-band.

  9. Pressure-correction method - Wikipedia

    en.wikipedia.org/wiki/Pressure-correction_method

    The correction for the velocity that is obtained from the second equation one has with incompressible flow, the non-divergence criterion or continuity equation. is computed by first calculating a residual value , resulting from spurious mass flux, then using this mass imbalance to get a new pressure value. The pressure value that is attempted ...

  10. Darcy friction factor formulae - Wikipedia

    en.wikipedia.org/wiki/Darcy_friction_factor_formulae

    If more than one formula is applicable in the flow regime under consideration, the choice of formula may be influenced by one or more of the following: Required accuracy; Speed of computation required; Available computational technology: calculator (minimize keystrokes) spreadsheet (single-cell formula) programming/scripting language (subroutine).

  11. Atmospheric correction - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_correction

    Atmospheric correction is the process of removing the scattering and absorption effects of the atmosphere on the reflectance values of images taken by satellite or airborne sensors. [1] [2] Atmospheric effects in optical remote sensing are significant and complex, dramatically altering the spectral nature of the radiation reaching the remote ...