Ads
related to: contact lenses priceswarbyparker.com has been visited by 10K+ users in the past month
Search results
Results from the WOW.Com Content Network
A Fresnel lens (/ ˈ f r eɪ n ɛ l,-n əl / FRAY-nel, -nəl; / ˈ f r ɛ n ɛ l,-əl / FREN-el, -əl; or / f r eɪ ˈ n ɛ l / fray-NEL [1]) is a type of composite compact lens which reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections.
In the 2017 fiscal year, such lenses accounted for 74.9% of all sales. [1] Interchangeable lenses for digital and conventional SLR cameras, including compact high-ratio zoom lenses of which Tamron was the pioneer in 1992 when it released the 28–200 mm. [3] The most-current lens of this type is the AF 16–300 mm F/3.5-6.3 Di II VC PZD MACRO ...
Contact Lens Precision Laboratories (CLPL), was founded in Cambridge in 1967. J. Keith Lomas, who was the company's managing director between 1996 and 2017, oversaw the acquisition of UltraVision in July 2003. [ 1 ]
The lens had a unique bayonet mount optics, "jumping" diaphragm and 13 aperture blades. The aperture control ring was placed on the back of the lens and switched in steps. The workmanship was of a very high standard. The second Helios-44 served as a standard lens for Zenit-3 SLR cameras in 1960-62.
A phakic intraocular lens (PIOL) is an intraocular lens that is implanted surgically into the eye to correct refractive errors without removing the natural lens (also known as "phakos", hence the term). Intraocular lenses that are implanted into eyes after the eye's natural lens has been removed during cataract surgery are known as pseudophakic.
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.
Ads
related to: contact lenses priceswarbyparker.com has been visited by 10K+ users in the past month