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  2. Eyeglass prescription - Wikipedia

    en.wikipedia.org/wiki/Eyeglass_prescription

    PL is an abbreviation for plano or plain, meaning no prescription; PD or IPD Pupillary Distance or Interpupillary Distance, respectively. It is the distance between pupil centers. BVD Back vertex distance is the distance between the back of the spectacle lens and the front of the cornea (the front surface of the eye). This is significant in ...

  3. List of optometric abbreviations - Wikipedia

    en.wikipedia.org/wiki/List_of_optometric...

    Optical centres Occ. Occupation OD oculus dexter (right eye) OH Ocular history OMB Oculo motor balance ONH Optic nerve head Oph Ophthalmoscopy OS oculus sinister (left eye) OU oculus uterque (both eyes) PD Pupillary distance PERRLA Pupils equal, round, reactive to light and accommodation PH Pinhole

  4. Cardinal point (optics) - Wikipedia

    en.wikipedia.org/wiki/Cardinal_point_(optics)

    Optical systems can be folded using plane mirrors; the system is still considered to be rotationally symmetric if it possesses rotational symmetry when unfolded. Any point on the optical axis (in any space) is an axial point. Rotational symmetry greatly simplifies the analysis of optical systems, which otherwise must be analyzed in three ...

  5. Lens - Wikipedia

    en.wikipedia.org/wiki/Lens

    A burning apparatus consisting of two biconvex lens. A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction.A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (elements), usually arranged along a common axis.

  6. Sagitta (optics) - Wikipedia

    en.wikipedia.org/wiki/Sagitta_(optics)

    where R is the radius of curvature of the optical surface. The sag S ( r ) is the displacement along the optic axis of the surface from the vertex, at distance r {\displaystyle r} from the axis. A good explanation both of this approximate formula and the exact formula can be found here .

  7. Corrective lens - Wikipedia

    en.wikipedia.org/wiki/Corrective_lens

    Higher-quality optical-grade glass materials exist (e.g. Borosilicate crown glasses such as BK7 ( n d = 1.51680 , V d = 64.17 , D = 2.51 g/cm³ ), which is commonly used in telescopes and binoculars, and fluorite crown glasses such as the best optical quality low dispersion glass currently in production, N-FK58 made by the German company Schott ...

  8. Fisheye lens - Wikipedia

    en.wikipedia.org/wiki/Fisheye_lens

    The term fisheye was ... The Pleon had a focal length of approximately 72.5 mm with a maximum aperture of f /8 and used a plano ... the former head of optical ...

  9. Radius of curvature (optics) - Wikipedia

    en.wikipedia.org/wiki/Radius_of_curvature_(optics)

    Radius of curvature sign convention for optical design. Radius of curvature (ROC) has specific meaning and sign convention in optical design.A spherical lens or mirror surface has a center of curvature located either along or decentered from the system local optical axis.