Presciption Eyeglasses Online

Prescription of Corrective Lenses

Corrective lenses are prescribed by an optometrist.

The prescription consists of all the specifications necessary to make the lens.

Prescriptions typically include the power specifications of each lens (for each eye).

Strengths are generally prescribed in quarter-diopter steps (0.25 D) because most people cannot generally distinguish between smaller increments (ex. eighth-diopter steps / 0.125 D).

A corrective lens is a lens worn in front of the, mainly used to treat myopia, hyperopia, astigmatism, and presbyopia .Glasses, or "spectacles" are worn on the face a short distance in front of the eye.

Contact lenses are worn directly on the surface of the eye.

Intraocular lenses are surgically implanted most commonly after cataract removal, but recently for after surgery or purely refractive purposes.

Myopia (near-sightedness) requires a divergent lens, whereas hyperopia (far-sightedness) requires convergent lens.

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Lens Type

Single Vision Lenses

Single vision has the same optical focal point or correction over the entire area of the lens.

They are prescribed when you need correction for one field of vision; for distance, or items up close.

We carry brand name single vision lenses. Trivex, Plastic, Polycarbonate, High Index, Photochromic.

Our selection include also Transition and polarized lenses.

DRIVEWEAR	ESSILOR	NIKON	SEIKO
GENTEX	HOYA	KBco	OPTIMA
PENTAX	RESOLUTION	TRANSITIONS	TRILOGY
XPERIO	ZEISS	NXT

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Bifocal

Bifocal the upper part of the lens is generally used for distance vision, while the lower part is used for near vision. Usually, a segment line separates the two.

Typically a person with myopia would have one section of a prescription lens that has a certain diverging power while another section of the lens would have a lower diverging power for close-up work.

Similarly a person with hyperopia would have one section of the lens with a certain converging power and another section with a greater power for close-up work.

Our bifocal selection include Trivex, Plastic, Polycarbonate, High Index, Photochromic, Transition and all other eyeglasses and sunglass bifoval lens options.

REGULAR PLASTIC

POLYCARBONATE

HIGH INDEX

PHOTOCHROMIC

TRANSITION

POLARIZED

SHAMIR LENS	YOUNGER OPTICS	KODAK	HOYA	SOLA
ESSILOR	VARILUX LENS	ZEISS

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Trifocal

Trifocal lenses are similar to bifocals, except that the two focal areas are separated by a third middle area with intermediate focus correction, used for intermediate vision, e.g. computer distance.

This lens type has two segment lines, dividing the three different correcting segments.

Trifocal lens Selection include:

REGULAR PLASTIC

POLYCARBONATE

HIGH INDEX

PHOTOCHROMATIC

TRANSITION

POLARIZED

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Progressive

Progressive, varifocal or no-line bifocals lens provide a smooth transition from distance correction to near correction, eliminating segment lines and allowing the viewing of all intermediate distances.

The lens have the gradual progressive corrective powers that do not cause eye strain and provide a more relaxed vision.

No one will ever know that you even need reading classes.

Attractive. Natural.

Call us for the brand name you are looking for.

Varilux Lenses

VARILUX	ZEISS	HOYA	ESSILOR
VARILUX LENS	SHAMIR LENS	RODENSTOCK	SEIKO

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Computer Lenses

If you are working long hours in front of a computer, these lens are just for you.

These lenses, having a larger intermediate zone then regular progressive lense, leave less space for distance making non suitable for driving or regular wear.

SHAMIR OFFICE LENS

HOYA

ZEISS

INTERVIEW

SOLA

ACCESS

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Sunglasses Lense

Replacement

We replace sunglasses lens.

PLASTIC

HIGH INDEX

POLARIZED

POLYCARBONATE

PHOTOCHROMATIC

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Aspheric

Aspheric lenses are typically designed to give a thinner lens, and also distort the viewer's eyes less as seen by other people, producing better aesthetic appearance.

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Over the Counter Correction

In some cases, mild farsightedness (hyperopia) can be treated with simple magnifying lenses or commodity reading glasses that can be purchased without a prescription. The magnifiers make the image of the object being viewed bigger so that it can be seen better. Over the counter readers are spherical corrective lenses of varying strengths (commonly +1.00D to +4.00D).

These treatments are not as tailored to the specific needs of the patient.

A difference in refractive error or presence of astigmatism will not be accounted for. The use of improper corrective lenses may not help or could even exacerbate binocular vision disorders.These treatments are not as tailored to the specific needs of the patient. A difference in refractive error or presence of astigmatism will not be accounted for. The use of improper corrective lenses may not help or could even exacerbate binocular vision disorders.

Over the counter readers may not work for patients with significant refractive errors requiring distance correction (unless they are used in combination with contact lenses that correct distance vision). Eyecare professionals (optometrists and ophthalmologists) are trained to determine the specific corrective lenses that will provide the clearest, most comfortable and most efficient vision, avoiding double vision and maximizing binocularity. They can tell patients if over the counter corrective lenses are appropriate.

Adjustable Focus

Adjustable or variable focus dynamically adjusts focal length to allow clear vision at any distance. It is especially useful for treating the loss of accommodation common in presbyopia.

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Cosmetics and Weight

Reducing Lens Thickness

Note that the greatest cosmetic improvement on lens thickness (and weight) is had from choosing a frame which holds physically small lenses.

The curves on the front and back of a lens are ideally formed with the specific radius of a sphere.

This radius is set by the lens designer based on the prescription and cosmetic consideration.

Selecting a smaller lens will mean less of this sphere surface is represented by the lens surface, meaning the lens will have a thinner edge (myopia) or center (hyperopia).

Index can improve the lens thinness, but at a point no more improvement will be realized. For example, if an index and lens size is selected with center to edge thickness difference of 1 mm then changing index can only improve thickness by a fraction of this. This is also true with aspheric design lenses. The lens's minimum thickness can also be varied.

The FDA ball drop test sets the minimum thickness of materials. Glass or CR-39 requires 2.0 mm, but some newer materials only require 1.5 mm or even 1.0 mm minimum thickness.

Weight

Material density typically increases as lens thickness is reduced by increasing index.

There is also a minimum lens thickness required to support the lens shape.

These factors results in a thinner lens which is not lighter than the original. There are lens materials with lower density at higher index which can result in a truly lighter lens. These materials can be found a material property table. Reducing frame lens size will give the most noticeable improvement in weight for a given material.

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Facial Distortion and Social Stigma

Eyeglasses for a high-diopter nearsighted or farsighted person cause a visible distortion of their face as seen by other people, in the apparent size of the eyes and facial features visible through the eyeglasses.

For extreme nearsightedness the eyes appear small and sunken into the face, and the sides of the skull can be visible through the lens.

This gives the wearer the appearance of having a very large or fat head in contrast with their eyes.

For extreme farsightedness the eyes appear very large on the face, making the wearer's head seem too small.

Either situation can result in social stigma for children and adults due to apparent unattractiveness or uglyness of the wearer caused by these facial distortions.

This can result in low self-esteem of the eyeglass wearer and lead to difficulty in making friends and developing relationships.

People with very high power corrective lenses can benefit socially from contact lenses because these distortions are minimized and their facial appearance to others is normal.

Aspheric/atoric eyeglass design can also reduce minification and magnification of the eye for observers at some angles.

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Lens Coating

Anti-reflective

Anti-reflective coatings help to make the eye behind the lens more visible.

They also help lessen back reflections of the white of the eye as well as bright objects behind the eyeglasses wearer (e.g., windows, lamps).

Such reduction of back reflections increases the apparent contrast of surroundings.

At night, anti-reflective coatings help to reduce headlight glare from oncoming cars, street lamps and heavily lit or neon signs.

One problem with anti-reflective coatings is that historically they have been very easy to scratch.

Newer coatings, such as Crizal Alizé with its 5.0 rating and Hoya's Super HiVision with its 10.9 rating on the COLTS Bayer Abrasion Test (glass averages 12-14), try to address this problem by combining scratch resistance with the anti-reflective coating.

They also offer a measure of dirt and smudge resistance, due to their hydrophobic properties (110° water drop contact angle for Super HiVision and 112° for Crizal Alizé).

Ultra Violet Protection

A UV coating is used to reduce the transmission of light in the ultraviolet spectrum.A UV coating is used to reduce the transmission of light in the ultraviolet spectrum.

UV-B radiation increases the likelihood of cataracts, while long term exposure to UV-A radiation can damage the retina.

DNA damage from UV light is cumulative and irreversible.

Some materials, such as Trivex and Polycarbonate naturally block most UV light and do not benefit from the application of a UV coating UV-B radiation increases the likelihood of cataracts, while long term exposure to UV-A radiation can damage the retina.

DNA damage from UV light is cumulative and irreversible. Some materials, such as Trivex and Polycarbonate naturally block most UV light and do not benefit from the application of a UV coating.

We deal with several companies who offer the best products.

CRIZAL	CRIZAL ALIZE	CRIZAL AVANCE	TEFLON CLEARCOAT
ZEISS SUPER ET	SHAMIR LENS	ZEISS CARAT	EVE

Scratch Resistance

Highly recommended, especially for polycarbonate and softer materials, to make lenses last longer.

This is done automatically by many labs for polycarbonate and high index lenses.