Glasses (चश्मा), also known as eyeglasses or spectacles, are devices consisting of glass or hard plastic lenses mounted in a frame that holds them in front of a person’s eyes, typically using a bridge over the nose and arms which rest over the ears. Glasses are typically used for vision correction, such as with reading glasses and glasses used for nearsightedness. People are more likely to need glasses the older they get with 93% of people between the ages of 60 and 75 wearing corrective lenses. Most of us do not know much about the glasses we use, hence Siddha Spirituality of Swami Hardas Life System makes us aware of our valuable readers. So read the article thoroughly and know the facts about glasses for wellbeing.
Visual risk factors (नजर की जोखिम)
Poor vision reduces postural stability and significantly increases the risk of falls and fractures in older people. Most studies have found that poor visual acuity increases the risk of falls. However, studies that have included multiple visual measures have found that reduced contrast sensitivity and depth perception are the most important visual risk factors for falls.
Multifocal glasses may add to this risk because their near-vision lenses impair distance contrast sensitivity and depth perception in the lower visual field. This reduces the ability of an older person to detect environmental hazards. There is now evidence that maximizing vision through cataract surgery is an effective strategy for preventing falls.
Glasses for eyes (आँखों के लिए चश्मा)
Glasses can be marked or found by their primary function, but also appear in combinations such as prescription sunglasses or safety glasses with enhanced magnification.
Corrective lenses (सुधारात्मक लेंस)
Corrective lenses are used to correct refractive errors by bending the light entering the eye in order to alleviate the effects of conditions such as nearsightedness, farsightedness or astigmatism. The ability of one’s eyes to accommodate their focus to near and distant focus alters over time. A common condition in people over forty years old is presbyopia, which is caused by the eye’s crystalline lens losing elasticity, progressively reducing the ability of the lens to accommodate i.e. to focus on objects close to the eye. Few people have a pair of eyes that show exactly equal refractive characteristics; one eye may need a “stronger” lens than the other.
Corrective lenses bring the image back into focus on the retina. They are made to conform to the prescription of an ophthalmologist or optometrist. A lensmeter can be used to verify the specifications of an existing pair of glasses. Corrective eyeglasses can significantly improve the life quality of the wearer. Not only do they enhance the wearer’s visual experience, but they can also reduce problems that result from eye strain, such as headaches or squinting.
Safety glasses (सुरक्षा का चश्मा)
Safety glasses are worn to protect the eyes in various situations. They are made with break-proof plastic lenses to protect the eye from flying debris or other matter. Construction workers, factory workers, machinists, and lab technicians are often required to wear safety glasses to shield the eyes from flying debris or hazardous splatters such as blood or chemicals.
Sunglasses (धूप का चश्मा)
Sunglasses provide more comfort and protection against bright light and often against ultraviolet (UV) light. To properly protect the eyes from the dangers of UV light, sunglasses should have a UV-400 blocker to provide good coverage against the entire light spectrum that poses a danger. Photochromic lenses, which are photosensitive, darken when struck by UV light. The dark tint of the lenses in a pair of sunglasses blocks the transmission of light through the lens.
Sunglasses may also have corrective lenses, which require a prescription. Clip-on sunglasses or sunglass clips can be attached to another pair of glasses. Some wrap-around sunglasses are large enough to be worn over top of another pair of glasses. Otherwise, many people opt to wear contact lenses to correct their vision so that standard sunglasses can be used.
The mixed double frame (मिश्रित डबल फ्रेम)
The double frame uplifting glasses have one moving frame with one pair of lenses and the basic fixed frame with another pair of lenses, that are connected by four-bar linkage. For example, sun lenses could be easily lifted up and down while mixed with myopia lenses that always stay on. Presbyopia lenses could be also combined and easily removed from the field of view if needed without taking off glasses.
3D glasses (3 डी चश्मा)
The illusion of three dimensions on a two-dimensional surface can be created by providing each eye with different visual information. 3D glasses create the illusion of three dimensions by filtering a signal containing information for both eyes. The signal, often light reflected off a movie screen or emitted from an electronic display, is filtered so that each eye receives a slightly different image. The filters only work for the type of signal they were designed for.
Magnification glasses (आवर्धन चश्मा)
Glasses can also provide magnification that is useful for people with vision impairments or specific occupational demands. An example would be bioptics or bioptic telescopes that have small telescopes mounted on, in, or behind their regular lenses. Newer designs use smaller lightweight telescopes, which can be embedded into the corrective glass and improve aesthetic appearance. They may take the form of self-contained glasses that resemble goggles or binoculars or may be attached to existing glasses.
Yellow-tinted glasses (पीला-रंगा हुआ चश्मा)
Yellow tinted glasses are a type of glasses with a minor yellow tint. They perform minor color correction, on top of reducing eyestrain due to lack of blinking. They may also be considered minor corrective unprescribed glasses. Depending on the company, these computers or gaming glasses can also filter out high energy blue and ultra-violet light from LCD screens, fluorescent lighting, and other sources of light. This allows for reduced eye-strain.
Anti-glare protection glasses (विरोधी चमक संरक्षण चश्मा)
Anti-glare protection glasses, or blue-light glasses, can reduce the reflection of light that enters our eyes. The lenses are given an anti-glare coating to prevent reflections of light under different lighting conditions. By reducing the amount of glare on your eyes, vision can be improved.
Glasses Frames (चश्मा की फ्रेम)
The ophthalmic frame is the part of a pair of glasses that are designed to hold the lenses in the proper position. Ophthalmic frames come in a variety of styles, sizes, materials, shapes, and colors.
Frame Parts (फ्रेम के पूर्जे)
- Pair of eye wires or rims surrounding and holding the lenses in place
- The bridge which connects the two eye wires
- Chassis, the combination of the eye wires and the bridge
- Top bar or brow bar, a bar just above the bridge providing structural support and/or style enhancement
- Brows or caps, plastic or metal caps that fit over the top of the eye wires for style enhancement and to provide additional support for the lenses
- Nose pads that allow a comfortable resting of the eye wires on the nose
- Pad arms connect the nose pads to the eye wires
- Temples (earpieces) on either side of the skull
- Pair of temple tips at the ends of the temples
- End pieces connect the eye wires via the hinges to the temples
- Frame-front end pieces
- Hinges connect the end pieces to the temples, allowing a swivel movement
Temple types (टेम्पल के प्रकार)
- Skull temples: bend down behind the ears, follow the contour of the skull and rest evenly against the skull
- Library temples: generally straight and do not bend down behind the ears. Hold the glasses primarily through light pressure against the side of the skull
- Convertible temples: used either as library or skull temples depending on the bent
- Riding bow temples: curve around the ear and extend down to the level of the ear lobe. Used mostly on athletic, children’s, and industrial safety frames
- Comfort cable temples: similar to the riding bow, but made from a springy cable of coiled metal, sometimes inside a plastic or silicone sleeve
Glasses Materials (चश्मा की सामग्री)
Plastic and polymer (प्लास्टिक और बहुलक)
- Cellulose acetate
- Optyl, a type of hypoallergenic material made especially for eyeglass frames
- Cellulose propionate, a molded, durable plastic
- 3D-printed plastic using super-fine polyamide powder and Selective Laser Sintering processes
Various metals and alloys may be used to make glasses such as gold, silver, aluminum, beryllium, stainless steel, titanium, and nickel-titanium.
Natural material (प्राकृतिक सामग्री)
Also, natural materials may be used such as wood, bone, ivory, leather and semi-precious or precious stones.
Corrective lens shape (सुधारात्मक लेंस का आकार)
Corrective lenses can be produced in many different shapes from a circular lens called a lens blank. Lens blanks are cut to fit the shape of the frame that will hold them. Frame styles vary and fashion trends change over time, resulting in a multitude of lens shapes. For lower power lenses, there are few restrictions that allow for many trendy and fashionable shapes. Higher power lenses can cause distortion of peripheral vision and may become thick and heavy if a large lens shape is used. However, if the lens becomes too small, the field of view can be drastically reduced.
Bifocal, trifocal, and progressive lenses generally require a taller lens shape to leave room for the different segments while preserving an adequate field of view through each segment. Frames with rounded edges are the most efficient for correcting myopic prescriptions, with perfectly round frames being the most efficient.
Glasses Invention (चश्मा आविष्कार)
The first eyeglasses were made in Northern Italy, most likely in Pisa, by about 1290. In a sermon delivered on 23 February 1306, the Dominican friar Giordano da Pisa wrote “It is not yet twenty years since there was found the art of making eyeglasses, which make for good vision and it is so short a time that this new art, never before extant, was discovered.
Developments of glasses (चश्मे का विकास)
The American scientist Benjamin Franklin, who suffered from both myopia and presbyopia, invented bifocals. Serious historians have from time to time produced evidence to suggest that others may have preceded him in the invention; however, correspondence between George Whatley and John Fenno, editor of The Gazette of the United States, suggested that Franklin had indeed invented bifocals, and perhaps 50 years earlier than had been originally thought. The first lenses for correcting astigmatism were designed by the British astronomer George Airy in 1825.
In the early 20th century, Moritz von Rohr and Zeiss developed the Zeiss Punktal spherical point-focus lenses that dominated the eyeglass lens field for many years.
In 2008, Joshua Silver designed eyewear with adjustable corrective glasses. They work by silicone liquid, a syringe, and a pressure mechanism.
Glasses in fashion (फैशन में चश्मा)
In the 1930s, “spectacles” were described as “medical appliances.” Wearing spectacles was sometimes considered socially humiliating. In the 1970s, fashionable glasses started to become available through manufacturers, and governments also recognized the demand for stylized eyewear.
Graham Pullin describes how devices for disability, like glasses, have traditionally been designed to camouflage against the skin and restore ability without being visible. In the past, design for disability has “been less about projecting a positive image as about trying not to project an image at all.”
Pullin uses the example of spectacles, traditionally categorized as a medical device for “patients”, and outlines how they are now described as eyewear: a fashionable accessory. Much like other fashion designs and accessories, eyewear is created by designers, has reputable labels, and comes in collections, by season and designer.
Glasses Styles (चश्मे की शैलियाँ)
In the 20th century, eyeglasses came to be considered a component of fashion; as such, various different styles have come in and out of popularity. Most are still in regular use, albeit with varying degrees of frequency.
- Aviator sunglasses
- Browline glasses
- Bug-eye glasses
- Cat eyeglasses
- GI glasses
- Horn-rimmed glasses
- Lensless glasses
- Rimless glasses
Glasses online (चश्मा ऑनलाइन)
The number of websites that sellhas proliferated over the past few years. More and more people are figuring out the same thing about that they learned about books 25 years ago. It’s not only easy to buy eyeglasses and contact lenses online, but it’s a whole lot cheaper, too as in hundreds of dollars in savings.
To that end, there are plenty of best online glasses vendors. However, before we dive in, note the following caveats, tips and prerequisites:
- You’ll need to know your prescription and pupillary distance before you use any of the sites, so make sure you get a hard copy the next time you get your eyes checked by an eye doctor. Once you have that, most of these sites will let you upload a picture of the prescription from your smartphone the first time you make a purchase.
- Most of the sites offer some sort of discount for first-time customers. That means the first time you buy glasses can be the best deal, so it can pay to try several online retailers before buying glasses online.
Choose best suiting glasses (फायदेमंद चश्मा चुनें)
For the most comfortable, durable and best-looking glasses, the following lens treatments should be considered essential:
Anti-scratch coating (खरोंच विरोधी परत)
All lightweight eyeglass lens materials have surfaces that are significantly softer and more prone to scratches and abrasions than glass lenses.
The softest eyeglass lens is also one of the most impact-resistant: polycarbonate. But all-plastic and high-index plastic lenses require a factory-applied anti-scratch coating for adequate lens durability.
Most of today’s modern anti-scratch coatings (also called scratch coats or hard coats) can make your eyeglass lenses nearly as scratch-resistant as glass. But if you’re not careful with your glasses or you’re buying eyeglasses for your kids, ask about lenses that include a warranty against scratches for a specific period of time.
Anti-reflective coating (परावर्तक – विरोधी लेप)
An anti-reflective coating makes all eyeglass lenses better. AR coatings eliminate reflections in lenses that reduce contrast and clarity, especially at night. They also make your lenses nearly invisible, so you can make better eye contact and others aren’t distracted by reflections in your lenses. AR-coated lenses are also much less likely to have glare spots in photographs.
Anti-reflective coating is especially important if you choose high-index lenses, because the higher the refractive index of lens material, the lighter the lenses reflect. In fact, high-index lenses can reflect up to 50 percent more light than CR-39 lenses, causing significantly more glare, unless AR coating is applied.
UV-blocking treatment (यूवी-अवरुद्ध उपचार)
Cumulative exposure to the sun’s harmful ultraviolet (UV) radiation over a person’s lifetime has been associated with age-related eye problems including cataracts and macular degeneration.
For this reason, people should protect their eyes from UV rays from early childhood. Thankfully, polycarbonate and nearly all high-index plastic lenses have 100 percent UV protection built-in, due to absorptive characteristics of the lens material.
But if you choose CR-39 plastic lenses, be aware that these lenses need an added coating to provide equal UV protection afforded by other lens materials.
Photochromic treatment (फोटोक्रोमिक उपचार)
This lens treatment enables eyeglass lenses to darken automatically in the sun’s UV and high-energy visible (HEV) light rays, and turn to clear (or nearly clear) when indoors.
Depending on the type of lenses and lens treatments you choose and the lens design you need, your eyeglass lenses can easily cost more than the frames you choose — even if you choose the latest designer frames.
Effects of not using glasses (चश्मे का उपयोग न करने के प्रभाव)
As a fashion statement, glasses are more popular than ever. But even with their newfound fame, some people who need glasses still aren’t wearing them. Whatever the reason may be, not wearing your glasses can have serious short-term and long-term effects.
Squinting, headaches, and fatigue (स्क्वाटिंग, सिरदर्द और थकान)
Risk of injury (घायल होने का खतरा)
Almost 90 percent of a person’s reaction ability while driving relies on sight, when someone gets behind the wheel without wearing glasses, they put themselves and others at a greater risk of injury.
Long-term effects (दीर्घकालिक प्रभाव)
More long-term effects of not wearing glasses may include incomplete development of the eyes.
People who have nearsightedness (also known as myopia) have difficulty seeing objects that are far away and can only focus on objects up close. An eyeglass prescription for someone who is nearsighted will contain a minus sign because power needs to be taken away from the eye to allow it to see at a distance.
When someone who is farsighted doesn’t wear glasses, the eyes have to work harder to focus, often leading to headaches and fatigue.
Wearing the right glasses (सही चश्मा पहने)
Wearing glasses that are too strong for near vision tasks can be just as problematic as not wearing corrective lenses. Reading glasses that are too strong will require the wearer to hold things closer to their face. Also, glasses with too strong of a prescription can cause headaches and fatigue.
Personalization is extremely important when it comes to optimizing performance with modern-day corrective lenses. Several factors like the position of the eyes, the angle and position of the frame, and the distance between pupils make prescription glasses unique for each wearer.
Prescription glasses should never be shared, even if the prescription value is assumed to be similar.