Search results
Results from the WOW.Com Content Network
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)
The formula for iseikonic lenses (without cylinder) is: Magnification = 1 ( 1 − ( t n ) P ) ⋅ 1 ( 1 − h F ) {\displaystyle {\textrm {Magnification}}={\frac {1}{(1-({\frac {t}{n}})P)}}\cdot {\frac {1}{(1-hF)}}}
In geophysics, the free-air gravity anomaly, often simply called the free-air anomaly, is the measured gravity anomaly after a free-air correction is applied to account for the elevation at which a measurement is made.
Where appropriate, prismatic correction can be used, either temporarily or permanently, to relieve symptoms of double vision. In specific cases, and primarily in adult patients, botulinum toxin can be used either as a permanent therapeutic approach, or as a temporary measure to prevent contracture of muscles prior to surgery
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.
If the patient saw a red line to the right and white light to the left, they are said to have esotropia or esophoria (uncrossed diplopia) in which base out (BO) prisms of increasing strength are used until the lines are superimposed.
Numbers and arrows should be seen clearly. Relaxation of accommodation can result in an increase in exophoria and a decrease in esophoria, leading to an inaccurate result; The examiner should check the function of the Maddox Wing Instrument before use; the septa can be easily bent, leading to the septa not covering the intended view.
K correction converts measurements of astronomical objects into their respective rest frames. The correction acts on that object's observed magnitude (or equivalently, its flux).
Vincenty's formulae are two related iterative methods used in geodesy to calculate the distance between two points on the surface of a spheroid, developed by Thaddeus Vincenty (1975a).
The normal gravity. The normal gravity accounts for the bulk gravitation of the entire Earth, corrected for its idealized shape and rotation. It is given by the formula: where = 9.780 327 m⋅s−2; = 5.302 44 × 10−3; and = −5.8 × 10−6. This is accurate to 0.1 mgal at any latitude .