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2. Corrective lens - Wikipedia

   en.wikipedia.org/wiki/Corrective_lens

   Corrective lens. A corrective lens is a transmissive optical device that is worn on the eye to improve visual perception. The most common use is to treat refractive errors: myopia, hypermetropia, astigmatism, and presbyopia. Glasses or "spectacles" are worn on the face a short distance in front of the eye.

3. Diffraction-limited system - Wikipedia

   en.wikipedia.org/wiki/Diffraction-limited_system

   An optical instrument is said to be diffraction-limited if it has reached this limit of resolution performance. Other factors may affect an optical system's performance, such as lens imperfections or aberrations, but these are caused by errors in the manufacture or calculation of a lens, whereas the diffraction limit is the maximum resolution ...

4. Abbe number - Wikipedia

   en.wikipedia.org/wiki/Abbe_number

   Abbe number. In optics and lens design, the Abbe number, also known as the V-number or constringence of a transparent material, is an approximate measure of the material's dispersion (change of refractive index versus wavelength), with high values of V indicating low dispersion. It is named after Ernst Abbe (1840–1905), the German physicist ...

5. Optical aberration - Wikipedia

   en.wikipedia.org/wiki/Optical_aberration

   1: Imaging by a lens with chromatic aberration. 2: A lens with less chromatic aberration. In optics, aberration is a property of optical systems, such as lenses, that causes light to be spread out over some region of space rather than focused to a point. [ 1] Aberrations cause the image formed by a lens to be blurred or distorted, with the ...

6. Vertex distance - Wikipedia

   en.wikipedia.org/wiki/Vertex_distance

   Vertex distance is the distance between the back surface of a corrective lens, i.e. glasses (spectacles) or contact lenses, and the front of the cornea. Increasing or decreasing the vertex distance changes the optical properties of the system, by moving the focal point forward or backward, effectively changing the power of the lens relative to ...

7. Subjective refraction - Wikipedia

   en.wikipedia.org/wiki/Subjective_refraction

   Subjective refraction. Subjective Refraction is a technique to determine the combination of lenses that will provide the best corrected visual acuity (BCVA). [1] It is a clinical examination used by orthoptists, optometrists and ophthalmologists to determine a patient's need for refractive correction, in the form of glasses or contact lenses.

8. Chromatic aberration - Wikipedia

   en.wikipedia.org/wiki/Chromatic_aberration

   Chromatic aberration. Focal length of lens varies with the color of light. In optics, chromatic aberration ( CA ), also called chromatic distortion, color aberration, color fringing, or purple fringing, is a failure of a lens to focus all colors to the same point. [ 1][ 2] It is caused by dispersion: the refractive index of the lens elements ...

9. Category:Corrective lenses - Wikipedia

   en.wikipedia.org/wiki/Category:Corrective_lenses

   A corrective lens is a lens worn on or before the eye. They are used to treat myopia , hypermetropia , astigmatism , and presbyopia . The main article for this category is Corrective lens .