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Information on Magnification Glasses
Almost everyone has used a magnification glass at some point, whether it’s to examine an object in science class or to make it easier to read the fine print of a document. And almost everyone has them lying around, these powerful devices that can make research and reading not just easier. For some, a magnifying glass makes it possible.
The Lens
The most important part of a magnification glass is the lens. The lens is the piece of glass that enlarges the image, by using a combination of light and refraction. While there are different types of lenses, the type used for magnification is a convex lens (meaning that the surface of the glass curves outward rather than inward).The curve of the lens must have complete axial symmetry to be effective—meaning that the curve of the lens is the same around the circle. When the light strikes the lens, it is refracted through the glass and makes anything viewed through the lens seem larger.
The First Magnifying Glass
The first magnifying glass was developed in approximately 1021 by Alhazen, an Arab/Persian scientist and mathematician. Alhazen was fascinated by the wonders of the human eye and how we perceive the world around us. He’s often been credited with being the father of optical science and was also one of the first to experiment with optical illusions. He was the first to examine and calculate the magnifying principles of the lens, documented what is perhaps one of his most famous works, The Book of Optics. It was in this book that the details and constants of magnification, mirrors and refraction were first outlined.The magnifying glass became popular in Europe in the 12th and 13th centuries—after Alhazen’s book was translated into Latin.
Focal Distance
Since the lens of the magnification glass is curved, the distance that the light must travel from the object, through the lens and into the eye of the person viewing it is different. This is why, when viewing an object through a magnification glass, the center of the object might be in sharp focus and become blurry near the edges. This is also why the viewer may find that moving the glass closer to or farther from the object will bring objects into sharper focus. Different people viewing the same object need to hold the glass at different distances to get the same effect. Each human eye is unique, and each individual must find the proper distances to get the desired effect, much like adjusting the field of a microscope.
Considerations
The amount that an object is magnified is also relative to an individual. While a glass might be rated at 2x (indicating that it will magnify the object two times), a person with poor eyesight might gain a more noticeable benefit from it. A magnifying glass typically works by bringing it closer to the eye in order to find what is called the near point—the point at which the image looks the clearest. In older individuals, the near point can be up to several meters away, making it seem as though the image is magnified much more than it would be to a younger person with a closer near point.
Limits
While magnification increases the size of the object and the detail that is visible, there is a limit to how much something can be magnified. The detail of an object can only be increased until it reaches the limit that the human eye can discern. Most hand-held magnifying glasses magnify an image about two times, or doubling the size and the amount of detail that can be seen.
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Get more and more varieties of magnifying glass with light here
LED Light with Reading Lens Glasses Magnifier
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Authentic Models Discovery Glass Magnifier $24.95 Examining maps, coins and other wonders couldn’t be easier with this Discovery Glass magnifier by Authentic Models. The piece is designed with an antique style brass finish that makes this collectible a must have for anyone with old world charm tastes…. |
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Authentic Models AC099 Magnifying Glass – AC099, $38.95 Magnifying Glass – AC099… |
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CellularFactory: Home & decor Home & Decor 30 x 21mm Eye Magnifier Glass Jeweler Loupe $1.00 The 30 x 21mm Jewelry Loupe Magnifier is made of high quality optical glass and in chrome plated coat. Very convenient to inspect tiny objects such as jewelry, stamps, coins and watch. Portable and easy to carryFEATURES: Round swing-away chrome plated case The lens of Eye Loupe Magnifier is made of optical glass for extra sharpness and clarity 30 times magnification power for extra sharpness and c… |
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Helping Hands with Magnifying Glass $1.56 Quality helping hands with solid heavy duty cast iron base, great for soldering and working with small items. Useful tool for electrician, engineers, jewelers and more. Helping hand comes with 2-1/2″ glass lens mangifier and 2 alligator clips mounted on 4 way swivels…. |
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Lightwedge Lighted Pocket Magnifier, Black $8.52 Slide open to activate the powerful LED light. The square lens provides strong 3x magnification, perfect for: crafts projects, menus, instruction manuals, maps, and more! This deluxe lighted magnifier is a great gift for crafters and readers. Slim and lightweight, fits easily into: pocket, purse, briefcase, glove compartment, and more. 5.75″H x 1.9″W x.5″D, 1.5″H x.38″W viewing window. Includes 2 … |
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Apex Bifocal Safety Glasses UV400 Magnifying Reading Eyewear 2.00 Magnifier $7.99 * Available in a variety of magnifications including 1.50,2.00,2.50… |
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Game Boy Advance Light Magnifier colors may vary $0.43 MAGNIFIES SCREEN FOR IMPROVED VIEWINGUPC : 738012138175Shipping Dimensions : 8.00in X 5.50in X 1.75inEstimated Shipping Weight : 0.4639… |
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Light and Magnifier for GameBoy Color $5.95 Game Boy Color owners have long complained about poor low-light performance and a small screen. This device, from Mad Catz, attempts to solve both problems. The compact unit clips onto the top of the Game Boy Color. A squared magnifying lens effectively enlarges the screen 150 percent, and two lights, one on either side of the lens, provide much-needed illumination. The only downside is that t… |
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Game Boy Advance SP Screen Magnifier $6.99 Enlarge Images For A Completely Immersive Gaming Experience. Features A Unique Compact Foldable Design. Quick & Easy Snap-on Fit…. |
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Fisherman Eyewear Slim Vision DDE10SV Magnifier + 2.50 Power Reading Glasses … |
