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Optical lens design is the process of designing a lens to meet a set of performance requirements and constraints, including cost and manufacturing limitations. Parameters include surface profile types (spherical, aspheric, holographic, diffractive, etc.), as well as radius of curvature, distance to the next surface, material type and optionally tilt and decenter.
This list covers optical lens designs grouped by tasks or overall type. The field of optical lens designing has many variables including the function the lens or group of lenses have to perform, the limits of optical glass because of the index of refraction and dispersion properties, and design constraints including realistic lens element center and edge thicknesses, minimum and maximum air ...
This is a documentation subpage for Template:3D glasses. It may contain usage information, categories and other content that is not part of the original template page. This template can be used in image captions to hint the reader about the anaglyphic nature of the image.
Different designs of progressive lenses have more or less of this distortion. Fitting: Progressive lenses require careful placement relative to the wearer's pupil centre for a distance-viewing reference position. Incorrect specification of the fitting location can cause problems for the wearer including (depending on the design of the lens ...
Hoya Corporation (Hoya株式会社, Hōya Kabushiki-gaisha) is a Japanese company manufacturing optical products such as photomasks, photomask blanks and hard disk drive platters, contact lenses and eyeglass lenses for the health-care market, [4] medical photonics, [5] lasers, photographic filters, medical flexible endoscopy equipment, and ...
Visual acuity with Near chart without correctors Visual acuity with eye chart at Near 15.7 inches (400 mm) and without (sc: Latin sine correctore) correctors (spectacles); Ncc is with (cc: Latin cum correctore) correctors. See Visual_acuity#Legal_definitions: VA OS Left visual acuity VA OD Right visual acuity VDU Visual display unit VF Visual field
Using a phoropter to determine a prescription for eyeglasses. An eyeglass prescription is an order written by an eyewear prescriber, such as an optometrist, that specifies the value of all parameters the prescriber has deemed necessary to construct and/or dispense corrective lenses appropriate for a patient.
For 6/6 = 1.0 acuity, the size of a letter on the Snellen chart or Landolt C chart is a visual angle of 5 arc minutes (1 arc min = 1/60 of a degree), which is a 43 point font at 20 feet. [10] By the design of a typical optotype (like a Snellen E or a Landolt C), the critical gap that needs to be resolved is 1/5 this value, i.e., 1 arc min.