The first thing most people look for when buying reading glasses -- is style. People want to look great, and reading glasses are a terrific accessory for that since others look you in the eyes first.
But there's more than fashion to consider when choosing reading glasses. Consider the quality of optics and the materials from which they're made.
Most eye care professionals recommend aspheric lenses. In 1990 aspheric lenses became one of the most popular and useful categories of lens. Conventional lenses have a front surface that's spherical, shaped like the surface of a ball. But aspheric lenses have a more complex front surface that gradually change it's curve from the center of the lens all the way out to the edge.
A basic principle of optics dictates that a slight distortion is created when wearers look away from the center of a conventional lens when the gaze is directed to the left or right, above or below. Aspheric lens designs eliminate those distortions. That's because, as the eye travels away from the center of the lens, the front curve changes, keeping optics crisp and clear.
Aspheric lenses are a lot like thin prescription high-index lenses. In a completely different way than high index, aspheric lenses also end up thinner than conventional lenses, even when made from conventional plastic. Aspheric lenses make your eyes look better to others, too. There's less "minification" of the eyes.
Another lens quality to be aware of is scratch resistance. Better reading glasses have scratch resistant lenses. Scratches on your lenses not only affect your vision, but can also affect the way you look.
A lot of people enjoy adjustable nose pads and spring temple hinges for comfort and fit.
Most popularly priced reading glasses have PVC (or ordinary plastic) lenses. There's nothing wrong with that but they don't provide the clearest vision possible. The best lenses for reading glasses are made of materials called C-39 or polycarbonate. They render the clearest vision. Unfortunately, they're more expensive than plastic.
Other items of which to be aware when buying reading glasses include the material from which the frames are constructed: Ordinary plastic is most affordable but lacks durability. Consider laminated acetate or Zyl.
Nickel-free Monel (hypo-allergenic) and stainless steel and are two of the best metals for the construction of reading glasses. They're durable and maintain their good looks as do laminated acetate and Zyl.If you're like most people, you'll want to make sure the reading glasses you select look great on your face. But make sure you choose the best quality reading glasses you can afford for clearer vision and a long term of use.
written by, Marc Levitt
Monday, July 21, 2008
Laser Vision Correction and Reading Glasses
Laser vision correction means you'll be able to drive and see TV without your glasses. But if you are over 40 years old, what about your reading vision?
Patients with good distance vision invariably become gradually more dependent on reading glasses around their mid forties. However if you are myopic (near sighted), you can read well without glasses, indeed you'll probably find yourself taking them off.
I often hear people tell me, "You mean I will still need glasses after the laser treatment, but now for reading? So what's the point?"
It does of course depend on the individual. For a taxi driver who just wants to be able to drive without glasses this is not a problem. But for a bank clerk who spends his entire day reading papers, suddenly requiring reading glasses for the first time will not be a welcome result after his laser treatment.
The solution to this problem is called Monovision. In Monovision we deliberately undercorrect one eye, the non-dominant eye, leaving it slightly myopic (near sighted), usually about -1.0 to -1.5. In this situation one eye, the fully corrected one, sees well for distance, and the other undercorrected eye sees well for near/reading.
In my experience about 75% of patients adapt well to this slight imbalance between the two eyes and no longer require glasses for distance or reading or any other daily activity. Pre-operative testing and counseling can select the best cases.
Farsighted candidates can also be helped with this technique although in their case they require an overcorrection (excess laser treatment) on one eye to make that eye deliberately slightly near sighted. Satisfaction in this group of patients is somewhat more difficult, but as far sighted people don`t see well either for near or for far, just giving them good distance vision is tremendously satisfying.
By Andrew Fink
Patients with good distance vision invariably become gradually more dependent on reading glasses around their mid forties. However if you are myopic (near sighted), you can read well without glasses, indeed you'll probably find yourself taking them off.
I often hear people tell me, "You mean I will still need glasses after the laser treatment, but now for reading? So what's the point?"
It does of course depend on the individual. For a taxi driver who just wants to be able to drive without glasses this is not a problem. But for a bank clerk who spends his entire day reading papers, suddenly requiring reading glasses for the first time will not be a welcome result after his laser treatment.
The solution to this problem is called Monovision. In Monovision we deliberately undercorrect one eye, the non-dominant eye, leaving it slightly myopic (near sighted), usually about -1.0 to -1.5. In this situation one eye, the fully corrected one, sees well for distance, and the other undercorrected eye sees well for near/reading.
In my experience about 75% of patients adapt well to this slight imbalance between the two eyes and no longer require glasses for distance or reading or any other daily activity. Pre-operative testing and counseling can select the best cases.
Farsighted candidates can also be helped with this technique although in their case they require an overcorrection (excess laser treatment) on one eye to make that eye deliberately slightly near sighted. Satisfaction in this group of patients is somewhat more difficult, but as far sighted people don`t see well either for near or for far, just giving them good distance vision is tremendously satisfying.
By Andrew Fink
How to Buy a Pair of Reading Glasses
As people age, it may become more difficult to read smaller print. You can correct this problem with a pair of reading glasses. Single vision reading glasses are available at your local drugstore, while more complex pairs need an optometrist' s prescription.
Step1
Visit your optometrist first if you suspect you need reading glasses. If you find you have to hold a newspaper or magazine far from your face to make out the print, you need reading glasses. An optometrist will be able to assess how severe your problem is, and recommend the proper eyeglass strength.
Step2
Try on different pairs if purchasing reading glasses at a drugstore. Reading glasses range from plus one diopter to plus 3.5. Check the chart at the eyeglass stand, which will include an eye chart for testing various glasses. If you can read the chart comfortably, without straining, it's probably the right pair for you.
Step3
Consider computer reading glasses if you spend a lot of time in front of your monitor. This type of reading glasses is relatively new, so ask your optometrist where to purchase them.
Step4
Determine if you need bifocals, which contain magnification in the bottom half of the glasses. You can see over the top of the frames without straining when using bifocals.
Step5
Choose a stylish frame. Whether your buy your pair of reading glasses at a drugstore, from your optician or over the Internet, there are countless frame colors, styles and patterns available to fit your personality.
written by, eHow
Step1
Visit your optometrist first if you suspect you need reading glasses. If you find you have to hold a newspaper or magazine far from your face to make out the print, you need reading glasses. An optometrist will be able to assess how severe your problem is, and recommend the proper eyeglass strength.
Step2
Try on different pairs if purchasing reading glasses at a drugstore. Reading glasses range from plus one diopter to plus 3.5. Check the chart at the eyeglass stand, which will include an eye chart for testing various glasses. If you can read the chart comfortably, without straining, it's probably the right pair for you.
Step3
Consider computer reading glasses if you spend a lot of time in front of your monitor. This type of reading glasses is relatively new, so ask your optometrist where to purchase them.
Step4
Determine if you need bifocals, which contain magnification in the bottom half of the glasses. You can see over the top of the frames without straining when using bifocals.
Step5
Choose a stylish frame. Whether your buy your pair of reading glasses at a drugstore, from your optician or over the Internet, there are countless frame colors, styles and patterns available to fit your personality.
written by, eHow
Why Custom-Made Reading Glasses Are Usually Better Than Pre-Fabricated Ones
Reading glasses can be custom-made for each individual through an optical dispenser, or they can be purchased "ready-made" at a pharmacy or department store. Ready-made readers became popular in the 1990s: three times more pairs were purchased during that decade than ever before, at an estimated rate of 30 million pairs per year. They are less expensive than custom eyewear, allowing you to own several pairs for a small amount of money.
Ready-made reading glasses are available in lots of fun styles and colors, too, so you can experiment with fashion, purchasing a somewhat outrageous pair of glasses without risking a lot of money. If you don't like the style, you can always get another inexpensive pair with a more conservative look. Pre-made reading glasses also allow you to stash extra pairs in different rooms of the house, as well as in your car, office, briefcase, purse, boat, and so on.
One drawback to purchasing ready-made ("drugstore") reading glasses is that they are essentially "one-size-fits-all" items. The prescription is the same in both lenses, and the location of the optical center of the lenses is not customized for each wearer. Most people do not have exactly the same prescription in both eyes, and almost everyone has at least a small amount of astigmatism correction in their prescriptions. Headaches, eyestrain, and even nausea can result from wearing reading glasses that are too far off from your actual prescription or that have optical centers too far away from the center of your pupils. If you experience these problems, visit your eye doctor for a customized reading glasses prescription.
Also, don't confuse reading glasses with computer eyewear. If you're using reading glasses to try to view your computer screen, it's probably not working very well. For one thing, reading printed matter is done at a closer range than reading text on a computer screen. Also, if your reading glasses are the type that force you to lean your head back in order to view your monitor, you're placing unnecessary strain on your neck muscles. Computer users really should invest in prescription computer eyeglasses.
When choosing ready-made reading glasses, always examine the lenses for little bubbles, waves, or other defects. Insist on the best quality, and if you can't find it in ready-made readers, buy a custom-made pair, which many eye care practitioners offer at special prices.
written by, Liz DeFranco
Ready-made reading glasses are available in lots of fun styles and colors, too, so you can experiment with fashion, purchasing a somewhat outrageous pair of glasses without risking a lot of money. If you don't like the style, you can always get another inexpensive pair with a more conservative look. Pre-made reading glasses also allow you to stash extra pairs in different rooms of the house, as well as in your car, office, briefcase, purse, boat, and so on.
One drawback to purchasing ready-made ("drugstore") reading glasses is that they are essentially "one-size-fits-all" items. The prescription is the same in both lenses, and the location of the optical center of the lenses is not customized for each wearer. Most people do not have exactly the same prescription in both eyes, and almost everyone has at least a small amount of astigmatism correction in their prescriptions. Headaches, eyestrain, and even nausea can result from wearing reading glasses that are too far off from your actual prescription or that have optical centers too far away from the center of your pupils. If you experience these problems, visit your eye doctor for a customized reading glasses prescription.
Also, don't confuse reading glasses with computer eyewear. If you're using reading glasses to try to view your computer screen, it's probably not working very well. For one thing, reading printed matter is done at a closer range than reading text on a computer screen. Also, if your reading glasses are the type that force you to lean your head back in order to view your monitor, you're placing unnecessary strain on your neck muscles. Computer users really should invest in prescription computer eyeglasses.
When choosing ready-made reading glasses, always examine the lenses for little bubbles, waves, or other defects. Insist on the best quality, and if you can't find it in ready-made readers, buy a custom-made pair, which many eye care practitioners offer at special prices.
written by, Liz DeFranco
Saturday, July 12, 2008
History of glasses
Precursors
The earliest historical reference to magnification dates back to ancient Egyptian hieroglyphs in the 8th century BC, which depict "simple glass meniscal lenses". The earliest written record of magnification dates back to the 1st century AD, when Seneca the Younger, a tutor of Emperor Nero, wrote: "Letters, however small and indistinct, are seen enlarged and more clearly through a globe of glass filled with water". Emperor Nero is also said to have watched the gladiatorial games using an emerald as a corrective lens.
Corrective lenses were said to be used by Abbas Ibn Firnas in the 9th century, who had devised a way to finish sand into glass. These glasses could be shaped and polished into round rocks used for viewing and were known as reading stones. The earliest evidence of "a magnifying device, a convex lens forming a magnified image," dates back the Book of Optics published by Alhazen in 1021. Its translation into Latin in the 12th century was instrumental to the invention of eyeglasses in 13th century Italy.
Sunglasses, in the form of flat panes of smoky quartz, protected the eyes from glare and were used in China in the 12th century or possibly earlier. However, they did not offer any corrective powers.
Invention of eyeglasses
Around 1284 in Italy, Salvino D'Armate is credited with inventing the first wearable eye glasses.The earliest pictorial evidence for the use of eyeglasses, however, is Tomaso da Modena's 1352 portrait of the cardinal Hugh de Provence reading in a scriptorium. Another early example would be a depiction of eyeglasses found north of the Alpes in an altarpiece of the church of Bad Wildungen, Germany, in 1403.
Many theories abound for who should be credited for the invention of traditional eyeglasses. In 1676, Francesco Redi, a professor of medicine at the University of Pisa, wrote that he possessed a 1289 manuscript whose author complains that he would be unable to read or write were it not for the recent invention of glasses. He also produced a record of a sermon given in 1305, in which the speaker, a Dominican monk named Fra Giordano da Rivalto, remarked that glasses had been invented less than twenty years previously, and that he had met the inventor. Based on this evidence, Redi credited another Dominican monk, Fra Alessandro da Spina of Pisa, with the re-invention of glasses after their original inventor kept them a secret, a claim contained in da Spina's obituary record.
Other stories, possibly legendary, credit Roger Bacon with the invention. Bacon is known to have made one of the first recorded references to the magnifying properties of lenses in 1262,though this was predated by Alhazen's Book of Optics in 1021. Bacon's treatise De iride ("On the Rainbow"), which was written while he was a student of Robert Grosseteste, no later than 1235, mentions using optics to "read the smallest letters at incredible distances". While the exact date and inventor may be forever disputed, it is almost certainly clear that spectacles were invented between 1280 and 1300 in Italy.
These early spectacles had convex lenses that could correct both hyperopia (farsightedness), and the presbyopia that commonly develops as a symptom of aging. Nicholas of Cusa is believed to have discovered the benefits of concave lens in the treatment of myopia (nearsightedness).
However, it was not until 1604 that Johannes Kepler published in his treatise on optics and astronomy, the first correct explanation as to why convex and concave lenses could correct presbyopia and myopia.
Later developments
The American scientist Benjamin Franklin, who suffered from both myopia and presbyopia, invented bifocals in 1784 to avoid having to regularly switch between two pairs of glasses.The first lenses for correcting astigmatism were constructed by the British astronomer George Airy in 1825.
Over time, the construction of spectacle frames also evolved. Early eyepieces were designed to be either held in place by hand or by exerting pressure on the nose (pince-nez). Girolamo Savonarola suggested that eyepieces could be held in place by a ribbon passed over the wearer's head, this in turn secured by the weight of a hat. The modern style of glasses, held by temples passing over the ears, was developed in 1727 by the British optician Edward Scarlett. These designs were not immediately successful, however, and various styles with attached handles such as "scissors-glasses" and lorgnettes remained fashionable throughout the 18th and into the early 19th century.
In the early 20th century, Moritz von Rohr at Zeiss (with the assistance of H. Boegehold and A. Sonnefeld), developed the Zeiss Punktal spherical point-focus lenses that dominated the eyeglass lens field for many years.
Despite the increasing popularity of contact lenses and laser corrective eye surgery, glasses remain very common as their technology has improved. For instance, it is now possible to purchase frames made of special memory metal alloys that return to their correct shape after being bent. Other frames have spring-loaded hinges. Either of these designs offers dramatically better ability to withstand the stresses of daily wear and the occasional accident. Modern frames are also often made from strong, light-weight materials such as titanium alloys, which were not available in earlier times.
On May 1, 1992 the United States Federal Trade Commission declared (section 456.2) that optometrists be required to provide the patient with a complete prescription immediately following an eye exam, effectively giving the patient the choice of where to purchase their glasses. The result was greater competition between the glasses manufacturers and thus lower prices for consumers. This trend has been accelerated by the proliferation of Internet technology, giving consumers the chance to bypass traditional distribution channels and buy glasses directly from the manufacturers.
Article source From Wikipedia, the free encyclopedia
The earliest historical reference to magnification dates back to ancient Egyptian hieroglyphs in the 8th century BC, which depict "simple glass meniscal lenses". The earliest written record of magnification dates back to the 1st century AD, when Seneca the Younger, a tutor of Emperor Nero, wrote: "Letters, however small and indistinct, are seen enlarged and more clearly through a globe of glass filled with water". Emperor Nero is also said to have watched the gladiatorial games using an emerald as a corrective lens.
Corrective lenses were said to be used by Abbas Ibn Firnas in the 9th century, who had devised a way to finish sand into glass. These glasses could be shaped and polished into round rocks used for viewing and were known as reading stones. The earliest evidence of "a magnifying device, a convex lens forming a magnified image," dates back the Book of Optics published by Alhazen in 1021. Its translation into Latin in the 12th century was instrumental to the invention of eyeglasses in 13th century Italy.
Sunglasses, in the form of flat panes of smoky quartz, protected the eyes from glare and were used in China in the 12th century or possibly earlier. However, they did not offer any corrective powers.
Invention of eyeglasses
Around 1284 in Italy, Salvino D'Armate is credited with inventing the first wearable eye glasses.The earliest pictorial evidence for the use of eyeglasses, however, is Tomaso da Modena's 1352 portrait of the cardinal Hugh de Provence reading in a scriptorium. Another early example would be a depiction of eyeglasses found north of the Alpes in an altarpiece of the church of Bad Wildungen, Germany, in 1403.
Many theories abound for who should be credited for the invention of traditional eyeglasses. In 1676, Francesco Redi, a professor of medicine at the University of Pisa, wrote that he possessed a 1289 manuscript whose author complains that he would be unable to read or write were it not for the recent invention of glasses. He also produced a record of a sermon given in 1305, in which the speaker, a Dominican monk named Fra Giordano da Rivalto, remarked that glasses had been invented less than twenty years previously, and that he had met the inventor. Based on this evidence, Redi credited another Dominican monk, Fra Alessandro da Spina of Pisa, with the re-invention of glasses after their original inventor kept them a secret, a claim contained in da Spina's obituary record.
Other stories, possibly legendary, credit Roger Bacon with the invention. Bacon is known to have made one of the first recorded references to the magnifying properties of lenses in 1262,though this was predated by Alhazen's Book of Optics in 1021. Bacon's treatise De iride ("On the Rainbow"), which was written while he was a student of Robert Grosseteste, no later than 1235, mentions using optics to "read the smallest letters at incredible distances". While the exact date and inventor may be forever disputed, it is almost certainly clear that spectacles were invented between 1280 and 1300 in Italy.
These early spectacles had convex lenses that could correct both hyperopia (farsightedness), and the presbyopia that commonly develops as a symptom of aging. Nicholas of Cusa is believed to have discovered the benefits of concave lens in the treatment of myopia (nearsightedness).
However, it was not until 1604 that Johannes Kepler published in his treatise on optics and astronomy, the first correct explanation as to why convex and concave lenses could correct presbyopia and myopia.
Later developments
The American scientist Benjamin Franklin, who suffered from both myopia and presbyopia, invented bifocals in 1784 to avoid having to regularly switch between two pairs of glasses.The first lenses for correcting astigmatism were constructed by the British astronomer George Airy in 1825.
Over time, the construction of spectacle frames also evolved. Early eyepieces were designed to be either held in place by hand or by exerting pressure on the nose (pince-nez). Girolamo Savonarola suggested that eyepieces could be held in place by a ribbon passed over the wearer's head, this in turn secured by the weight of a hat. The modern style of glasses, held by temples passing over the ears, was developed in 1727 by the British optician Edward Scarlett. These designs were not immediately successful, however, and various styles with attached handles such as "scissors-glasses" and lorgnettes remained fashionable throughout the 18th and into the early 19th century.
In the early 20th century, Moritz von Rohr at Zeiss (with the assistance of H. Boegehold and A. Sonnefeld), developed the Zeiss Punktal spherical point-focus lenses that dominated the eyeglass lens field for many years.
Despite the increasing popularity of contact lenses and laser corrective eye surgery, glasses remain very common as their technology has improved. For instance, it is now possible to purchase frames made of special memory metal alloys that return to their correct shape after being bent. Other frames have spring-loaded hinges. Either of these designs offers dramatically better ability to withstand the stresses of daily wear and the occasional accident. Modern frames are also often made from strong, light-weight materials such as titanium alloys, which were not available in earlier times.
On May 1, 1992 the United States Federal Trade Commission declared (section 456.2) that optometrists be required to provide the patient with a complete prescription immediately following an eye exam, effectively giving the patient the choice of where to purchase their glasses. The result was greater competition between the glasses manufacturers and thus lower prices for consumers. This trend has been accelerated by the proliferation of Internet technology, giving consumers the chance to bypass traditional distribution channels and buy glasses directly from the manufacturers.
Article source From Wikipedia, the free encyclopedia
What Are Glasses For Reading?
People who have trouble with their near or close-up vision, usually keep reading material at arms length or try and squint to make out the words. Such people have compromised near vision and require glasses for reading.
Reading glasses have a kind of magnifying lens, which magnifies the words on a page so that you can see and read them better. Glasses for reading are mostly useful for reading as well as concentrating on things and items close to you. If you try to see in the distance with your reading glasses, then you will not be able to see things clearly as everything will appear blurry. Thus, eyeglasses for reading are not the same as the regular kind of eye glasses for distance vision correction.
Article source from All-About-Eyeglasses.com
Reading glasses have a kind of magnifying lens, which magnifies the words on a page so that you can see and read them better. Glasses for reading are mostly useful for reading as well as concentrating on things and items close to you. If you try to see in the distance with your reading glasses, then you will not be able to see things clearly as everything will appear blurry. Thus, eyeglasses for reading are not the same as the regular kind of eye glasses for distance vision correction.
Article source from All-About-Eyeglasses.com
An Introduction To Reading Glasses
Do you often have difficulty reading things or seeing things close to you but have no problem with your far away vision? Do you often find yourself keeping a book or any reading material a little further away from yourself, in order to see better? If so, then you may need reading glasses.
When you reach the point of not being able to read up close without stretching your arms to the limit, you may need to consider single-vision reading glasses. Reading glasses come in two main styles: full frames, in which the entire lens is made in the reading prescription, and half-eyes, the smaller "Ben Franklin" style glasses that sit lower down on the nose.
Full reading glasses are suitable for people who spend a great deal of time concentrating on material close-up. If you try to look up and across the room through the reading lenses, everything appears blurry.
In contrast, half-eye reading glasses allow you to look down and through the lenses for near work, and up and over them to see in the distance. Generally, people who have never needed glasses in the past will start out with a pair of reading glasses rather than bifocals or no-line progressive lenses (which are usually a better choice if you have a need for distance as well as near correction).
Handy accessories for temporary use, such as an evening in a dimly lit restaurant, include tiny foldable readers that fit in pen-sized cases and magnifiers that hang around your neck like a pendant. You may have even seen plastic lenses mounted in credit card-sized holders that slip easily in a wallet — horrible for reading a book, but fine for those moments of desperation when you just want to know if the menu says "filet de boeuf" or "foie gras."
Also available are tinted reading glasses with UV protection for wearing outdoors in the sun; a popular type is the sunglass bifocal, with a nonprescription upper half for looking far away and a reading prescription in the lower half for close up.
When you reach the point of not being able to read up close without stretching your arms to the limit, you may need to consider single-vision reading glasses. Reading glasses come in two main styles: full frames, in which the entire lens is made in the reading prescription, and half-eyes, the smaller "Ben Franklin" style glasses that sit lower down on the nose.
Full reading glasses are suitable for people who spend a great deal of time concentrating on material close-up. If you try to look up and across the room through the reading lenses, everything appears blurry.
In contrast, half-eye reading glasses allow you to look down and through the lenses for near work, and up and over them to see in the distance. Generally, people who have never needed glasses in the past will start out with a pair of reading glasses rather than bifocals or no-line progressive lenses (which are usually a better choice if you have a need for distance as well as near correction).
Handy accessories for temporary use, such as an evening in a dimly lit restaurant, include tiny foldable readers that fit in pen-sized cases and magnifiers that hang around your neck like a pendant. You may have even seen plastic lenses mounted in credit card-sized holders that slip easily in a wallet — horrible for reading a book, but fine for those moments of desperation when you just want to know if the menu says "filet de boeuf" or "foie gras."
Also available are tinted reading glasses with UV protection for wearing outdoors in the sun; a popular type is the sunglass bifocal, with a nonprescription upper half for looking far away and a reading prescription in the lower half for close up.
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