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lens
lens
lens A transparent biconvex structure in the eyes or analogous organs of many animals, responsible for directing light onto light-sensitive cells. In vertebrates it is a flexible structure centred behind the iris and attached by
suspensory ligaments to the
ciliary body. In terrestrial species its main function is to focus images onto the retina. To focus on near objects, the circular muscles in the ciliary body contract and the lens becomes more convex; contraction of the radial muscles in the ciliary body flattens the lens for focusing on distant objects (see also
accommodation).
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Lens stem cells may reside outside the lens capsule: an hypothesis.(Commentary)(Clinical report)
Magazine article from: Theoretical Biology and Medical Modelling; 6/8/2007; ; 700+ words
; ...corresponding author) [1]; Rita A Meyer [2] Background Lens background The vertebrate lens is a transparent cellular structure, specialized to focus and transmit light. The lens is composed of two cell types - epithelial cells...
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LENSES INTO FOCUS -- How lenses work and how to choose them.(Statistical Data Included)
Magazine article from: Digital Video Magazine; 4/1/2002; ; 700+ words
; ...the more wide angle the lens. All prime lenses have a fixed focal length...operators to consider prime lenses. With a zoom lens, users can increase and...the more expensive the lens. Adapters and extenders Lenses for all types of cameras...
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Camera lenses.
Magazine article from: PSA Journal; 1/1/1991; ; 700+ words
; ...needed in a fine lens. f) In reality, most of today's lenses are capable of producing...above. Normal Lens Before taking up...and "accessory lenses," let's define...point behind the lens so clearance is achieved.) These normal lenses have a focal length...
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 "The Daily Mail (London, England)")
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Lenses to boost your sight while you sleep.
Newspaper article from: The Daily Mail (London, England); 6/24/2008; 700+ words
; ...seem fuzzy. Overnight lenses are made from a special hard type of plastic lens, called gaspermeable...already available as day lenses, but most people wear...of the cornea, the lens will be more effective.'Overnight lenses are not suitable for...
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 "Rocky Mountain News (Denver, CO)")
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LENSES FIX PATIENTS' LOOKS CONTACTS CORRECT APPEARANCE OF EYES DAMAGED BY INJURY.(Business)
Newspaper article from: Rocky Mountain News (Denver, CO); 2/17/1997; ; 700+ words
; ...in Colors also paints lenses for Halloween, such as cat eyes and an all-white lens that Harper thinks looks...The company even crafts lenses for people with dyslexia...FILE:EYEWEAR - CONTACT LENSES CAPTION: Artist Annalise...hand-painted contact lens. By Steve Groer / Rocky...
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Lenses for Every Eye.
Magazine article from: U.S. News & World Report; 3/5/2007; ; 700+ words
; ...silicone hydrogel lenses, an improved version of the soft lens introduced in 1971...permeable rigid lenses. That's important...you're getting a lens that breathes better...Association's contact lens and cornea section...silicone hydrogel lenses increased 50 percent...
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Lens solution makers need to account for 'human factors'.
Newspaper article from: Medical Device Daily; 6/12/2008; 700+ words
; ...state that makers of contact lens solutions should come up...proof way to ensure that lenses are sterile, the subtext...the efficacy of contact lens solutions on lenses is complicated by the wide range of lens types on the market...
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Lens hoods.
Magazine article from: PSA Journal; 8/1/1995; ; 700+ words
; ...precision cameras and lenses advise the use of a lens hood. This is sufficient...sizes for different lenses. Also, besides...hood protects the lens from rain and fingerprints...no wider than the lens mount are essential...manufacturers of such lenses include a threaded...
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Lens material is a triple jump in technology
Magazine article from: Ophthalmology Times; 3/15/2006; ; 700+ words
; ...and casting for lens production. Its...properties allow lenses made from Trivex...depending on the lens design. As a result, lenses made from the material...tension to which a lens material can respond...without breaking. Lenses made from Trivex...
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Contact Lenses-a New Way to See
Newspaper article from: The Washington Post; 5/22/1990; ; 700+ words
; ...forced under the lens. Even so, it...people who wear hard lenses to take them out...careful. For contact lens wearers, that means...and care for the lenses. Lenses must be...on them. Contact lens wearers can't take...taking care of their lenses. Wearing dirty lenses...
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contact lenses
Book article from: The Oxford Companion to the Body
contact lenses The contact lens provides a good example...for reusable, hard lenses is banished. Contact lens fitting has always been...features of the contact lens itself. Making specially shaped contact lenses to reduce their rotation...
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lens
Book article from: The Columbia Encyclopedia, Sixth Edition
...known as a crystalline lens. Classification of Lenses All rays of light...and Production of Lenses Generally each curved surface of a lens is made as a portion...focal length of the lens. It varies with different lenses, according to the...
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Eyeglass Lens
Book article from: How Products Are Made
Eyeglass Lens Background Eyeglass lenses are glass or plastic optical...virtually replaced by glass lenses. The convex lens was the first optical lens...but other corrective lenses followed, including the concave lens for the correction of near...
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Camera Lens
Book article from: How Products Are Made
...replacing a simple lens with a group of lenses called lens elements, which are lenses of different shapes and distances of separation...disposable cameras are equipped with panoramic lenses. A fish-eye lens is also a special kind of wide-angle lens...
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Contact Lens
Book article from: How Products Are Made
...prefer contact lenses over glasses for...prefer contact lens because of the...a-day contact lenses are gaining popularity among lens wearers. These...of any contact lens may differ depending...Process Contact lenses may be produced...
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