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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)
Prism spectacles with a single prism perform a relative displacement of the two eyes, thereby correcting eso-, exo, hyper- or hypotropia. In contrast, spectacles with prisms of equal power for both eyes, called yoked prisms (also: conjugate prisms , ambient lenses or performance glasses ) shift the visual field of both eyes to the same extent.
The stereographic projection gives a way to represent a sphere by a plane. The metric induced by the inverse stereographic projection from the plane to the sphere defines a geodesic distance between points in the plane equal to the spherical distance between the spherical points they represent.
The formula for iseikonic lenses (without cylinder) is: = (()) where: t = center thickness (in metres); n = refractive index; P = front base curve (in 1/metres); h = vertex distance (in metres);
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
Bolometric correction. In astronomy, the bolometric correction is the correction made to the absolute magnitude of an object in order to convert its visible magnitude to its bolometric magnitude. It is large for stars which radiate most of their energy outside of the visible range.
A psychrometric chart is a graph of the thermodynamic parameters of moist air at a constant pressure, often equated to an elevation relative to sea level. The ASHRAE -style psychrometric chart, shown here, was pioneered by Willis Carrier in 1904. [9]
A Schmidt–Pechan prism is a type of optical prism used to rotate an image by 180°. These prisms are commonly used in binoculars as an image erecting system. The Schmidt–Pechan prism makes use of a roof prism section (from the German: "Dachkante", lit. roof edge).
The CRC Handbook of Chemistry and Physics defines specific rotation as: For an optically active substance, defined by [α] θ λ = α/γl, where α is the angle through which plane polarized light is rotated by a solution of mass concentration γ and path length l.
A Pellin–Broca prism is a type of constant-deviation dispersive prism similar to an Abbe prism. The prism is named for its inventors, the French instrument maker Ph. Pellin and professor of physiological optics André Broca .