At the behest of the opticshe lens it’s a object normally made of glass, transparent, whose faces are not flat but are curved and as a consequence of the phenomenon of refraction, the rays of light that fall on one of the faces will be diverted and will appear on the other. It is normally used in various elements used in optics.
Meanwhile, the lens can be convergent or convexthat is, it has a greater thickness in the center than at the ends, or failing that, it can be divergent or concavehaving greater thickness at the ends than in the central part.
Lenses are generally used for correct vision difficulties of human beings and are also present in instruments such as: magnifying glasses, cameras, image projectors, telescopes and microscopesthe latter two used in scientific research contexts.
It should be noted that the first telescope to make astronomical appreciations was created by Galileo Galileiusing both a converging or positive lens and a diverging or negative lens.
On the other hand, the lenses that are used to correct vision problems, also known as glasses, spectacles, and bifocals, consist of two crystals that are attached through a frame. These lenses have different powers and are used especially in cases of presbyopia, myopia or farsightedness.
Other types of lens are: contact lens (They are lenses that are concave on one side and convex on the other, which are placed in the eye, more precisely in the cornea, for cosmetic purposes, to change the original color of the eyes, or to reduce vision problems) and intraocular lens (This is a type of lens that can be made of silicone or acrylic and is surgically implanted in the patient’s eye with the intention of improving a condition in the lens or in the shape of the cornea.)
On the other hand, those lenses that are used with the intention of protecting the eyesight from the sun’s rays are also called sun glasses.
The aforementioned terms of glasses and glasses are the ones that are mostly used as synonyms with this term.
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