Y O U R   P R E S C R I P T I O N

YOUR PRESCRIPTION

Common abbreviations for various portions of your prescription:

OD & OS  

OD (Oculus Dexter) is right eye, OS (Oculus Sinister) is left eye, both in Latin.

 

SPH 

The Spherical (Sph) number is the refractive correction for near (-) or far (+) sightedness.  If  PL or Plano is written here, it means Zero.

 

CYL & Axis 

The Cylinder (Cyl) and Axis define the correction for an astigmatism, which is a slightly oblong condition of the eye.   

 

The Cylinder (Cyl) is the extent of the oblongedness while the Axis is the angle, from 1 to 180 degrees of the astigmatism.  If the optometrist wrote "DS" or "Sph" or "Spherical" in the Cylinder space, it indicates no correction and should be entered as 0 on the order form. This means that  the eyeball is spherical and has no oblongedness, and consequently has no Cylinder or Axis values.

 

Axis – Axis refers to the angle of the correction for the astigmatism in the eye (if one exists) from 1 to 180. The Axis value is usually written as 3 digits, which means if your Axis value is 5, it is often written as 005. This Axis value is still 5, regardless of how it is displayed.

 

ADD
The Add is the correction for bifocal reading/near-vision.  This must be entered when ordering Bifocals or Progressives. 

If you have a prescription for multifocal glasses but want to order single-vision,  just leave the Add number off when filling out the order form. 

 

TYPES OF LENSES

• Single-Vision
  Single-Vision
  

  Single Vision lenses are the standard eyeglass prescription. These glasses are for one field of vision across the entire lens, whether specifically for distance vision, near-vision reading glasses or somewhere in-between such as computer-distance glasses.

  
  
• Bifocal

   BIFOCAL
  

   

  A lens with two fields of vision seperated by a line. Generally the top is designated for distance-vision or computer-distance and the bottom for near-vision work such as reading. 

   

  The total lens height for a Bifocal lens must be 30mm or greater. We recommend a taller lens for more comfortable wear, but 30mm is the minimum height for a bifocal lens. If the frame chosen has a lens height smaller than 30mm, a different frame must be chosen for Bifocal lenses.

   

  In a Bifocal lens, the two fields of vision are specifically differentiated by a visible line. The bottom reading area is 25mm wide and is positioned just below the centerline of the lens. The physical position of the bi-focal area will be affected by the physical height of the lens chosen.

   

   

• Progressive
  Progressive

   

  Progressive lens design includes three fields of vision, without lines, and is sometimes referred to as a "no-line bifocal". 

   

  In a Progressive lens, the shape of the corrected part of the lens is approximately that of a funnel or a mushroom, with the top portion for distance-vision, narrowing to the lower middle for mid-range (corridor), finally to the bottom portion for the near-vision or reading. The reading area is approximately the lower quarter, central third of the lens. The height of the progressive corridor can be short, medium or long, and is dependent on the height of the lens: the taller the lens, the longer the corridor. The corridor begins just above the centerline of the lens.

  
  
  
  The total lens height for any Progressive lens must be 30mm or greater.

   

  
  
• Photochromic

  Photochromic Lenses
  Photochromic lenses progressively darken outside in sunlight to become sunglasses. Our Photochromic lenses darken according to the amount of sunlight the lenses are exposed to. The shade of the lenses is slightly lighter than regular sunglasses and take a minute or two to transition to the darkened shade. Likewise, when moved out of the sun, the lenses take a minute or two to return to clear lenses.

  
  

  For dark, 80% prescription sunglasses you might consider one of our magnetic sunlens snap-on models, or a dark sunglass tint on one of our regular prescription eyeglasses for + $4.95. Either option might provide a far cheaper and often a better solution than a photochromic lens.
  

PRESCRIPTION AND LENS TYPE

• 1.57 Mid-Index Single-Vision, No Charge

  1.57 Mid Index

  
  

  A mid-index lens, which is thinner and lighter than the commonly used low-index lens, and is appropriate for most low- and mid-strength prescriptions. "Index" refers to the refractive quality of the lens, or the degree to which the lens bends light passing through it.

  
  
  
• 1.50 Standard Single-Vision, No Charge

  1.50 Standard Single Vision

  
  

  A commonly used lens appropriate for most prescriptions.

  
  
  
• 1.59 PC(Polycarbonate)Single-Vision

  1.59 PC(Polycarbonate)Single-Vision

  
  

  A lightweight and extremely impact-resistant lens. AR coating is strongly recommended with Polycarbonate lenses for glare reduction and better night-vision.

  
  
  
  
• 1.61 High-Index Single-Vision - Appropriate For Strong Prescriptions: Beyond -4 or +3 (Producing A Thinner Lighter Lens)

  1.61 High-Index Single-Vision

  
  
  

  A thinner, lighter lens than low- or mid- index, for use with strong prescriptions, generally with prescriptions equal to, or stronger than -4.00 or +3.00. High index lenses are those above our lower-index lenses, and are made with special lens materials that bend light more efficiently than lower index lenses. "Index" refers to the refractive quality of the lens, or the degree to which the lens bends light passing through it.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  
• 1.67 Very High-Index Single-Vision - Appropriate For Strong Prescriptions: Beyond -4 or +3 (Producing A Thinner Lighter Lens)

  1.67 High-Index Single-Vision

  
  
  

  A thinner, lighter lens than low- or mid- index, for use with strong prescriptions, generally those equal to, or stronger than -4.00 or +3.00. High index lenses are those above our standard index lens, and are made with special lens materials that bend light more efficiently than lower index lenses. "Index" refers to the refractive quality of the lens, or the degree to which the lens bends light passing through it.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  
• 1.74 Ultra High-Index Single-Vision - Appropriate For Strong Prescriptions: Beyond -5 or +4 (Producing A Thinner Lighter Lens)

  1.74 High-Index Single-Vision

  
  
  

  The highest index lens we sell, this is a very thin and lightweight lens for use only with very strong prescriptions, generally those equal to, or stronger than -5.00 or +4.00. High index lenses are those above our standard index lens, and are made with special lens materials that bend light more efficiently than lower index lenses. "Index" refers to the refractive quality of the lens, or the degree to which the lens bends light passing through it.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  
• 1.57 Photochromic + Single Vision

  1.57 Photochromic + Single-Vision

  
  

  A mid-index lens is thinner and lighter than the commonly used low-index lens and is appropriate for most low- and mid-strength prescriptions. "Index" refers to the refractive quality of the lens, or the degree to which the lens bends light passing through it.

  
  

  Photochromic lenses gradually darken outside in sunlight to become sunglasses. The shade in the lenses is determined by the amount of sunlight hitting the lens, and when moved indoors out of the sunlight, the lens returns to clear. 
  

• 1.61 Transitions® VI Photochromic Single Vision - Grey

  1.61 Transitions® Photochromic Single-Vision - Grey

  
  
  

  This high-index lens is a thinner, lighter lens than low- or mid- index, for use with strong prescriptions, generally those equal to, or stronger than -4.00 or +3.00. High index lenses are those above our standard index lens, and are made with special lens materials that bend light more efficiently than lower index lenses. "Index" refers to the refractive quality of the lens, or the degree to which the lens bends light passing through it.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  
  

  Transitions® lenses contain patented photochromic dyes which cause the lens to activate - or darken - when exposed to ultraviolet (UV) rays from sunlight. When the UV light diminishes, the lenses fade back to clear. As outdoor light conditions change, the level of darkness adjusts, creating just the right level of tint and allowing just the right amount of light to enter the eyes at any given time. This action allows Transitions® lenses to help protect your eyes from the light you can see - reducing glare, diminishing eye strain and fatigue and enabling you to distinguish contrast more easily.

  PLEASE NOTE: Photochromic lenses cannot be tinted.

  
  
  
• 1.67 Transitions® VI Photochromic Single Vision - Grey

  1.67 Transitions® Photochromic Single-Vision - Grey

  
  
  

  This high-index lens is a thinner, lighter lens than low- or mid- index, for use with strong prescriptions. High index lenses are those above our standard index lens, and are made with special lens materials that bend light more efficiently than lower index lenses.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  
  

  Transitions® lenses contain patented photochromic dyes which cause the lens to activate - or darken - when exposed to ultraviolet (UV) rays from sunlight. When the UV light diminishes, the lenses fade back to clear. As outdoor light conditions change, the level of darkness adjusts, creating just the right level of tint and allowing just the right amount of light to enter the eyes at any given time. This action allows Transitions® lenses to help protect your eyes from the light you can see - reducing glare, diminishing eye strain and fatigue and enabling you to distinguish contrast more easily.

  PLEASE NOTE: Photochromic lenses cannot be tinted.

  
  
  
• 1.50 Bifocal (with a line)

  1.50 Bifocal(with a line)

  
  

  A low-index lightweight lens, commonly used for the majority of glasses made. "Index" refers to the refractive quality of the lens, or the degree to which the lens bends light passing through it. The 1.50 index lens has good impact-resistance and is appropriate for most prescriptions.

  
  

   

  Bifocal lenses contain two fields of vision seperated by a line, generally with the top for distance or computer-distance, and the bottom for near-vision work such as reading. The reading area is 25mm wide and is positioned just below the centerline of the lens. The physical height of the bifocal area will be affected by the height of the lens chosen.

   

  The total lens height for a Bifocal lens must be 30mm or greater. We recommend a taller lens for more comfortable wear, but 30 mm is the minimum height for a bifocal lens. If the frame chosen has a lens height smaller than 30mm, a different frame must be chosen for bifocal lenses.

   

   

• 1.50 Progressive (No-line Multi-Focal)

  1.50 Progressive (No-line multi-focal)

  
  

  The 1.50 index lens is appropriate for most prescriptions.

  
  

  Progressive lenses include three fields of vision, without lines, and are sometimes referred to as no-line bifocals. The top portion of the lens corrects for distance-vision, narrowing to the lower middle for mid-range, finally to the bottom portion for the near-vision or reading.

  
  

  The lens height for any Progressive lens must be 30mm or greater

  .
  
  
• 1.57 Progressive (No-line Multi-Focal)

  1.57 Progressive (No-line multi-focal)

  
  

  A mid-index lens is thinner and lighter than the commonly used low-index lens, and is appropriate for most low- and mid-strength prescriptions.

  
  

  Progressive lenses include three fields of vision, without lines, and are sometimes referred to as a "no-line bifocal". 

   

  In a progressive lens, the top portion corrects for distance-vision, narrowing to the lower middle for mid-range vision, finally to the bottom portion for near-vision or reading.

  
  

  The lens height for any Progressive lens must be 30mm or greater.

   

  
  

   

  
  
• 1.59 PC (Polycarbonate - High Impact Lens For Additional Safety Protection) Progressive (No-line Multi-Focal)

  1.59 PC (Polycarbonate)Progressive (no-line multifocal)

  
  

  A lightweight and extremely impact-resistant lens. AR coating is strongly recommended with Polycarbonate lenses for glare reduction and better night-vision.

  
  

  Progressive lenses includes three fields of vision, without lines, and are sometimes referred to as a "no-line bifocal". 

   

  In Progressive lenses, the top portion corrects for distance-vision, narrowing to the lower middle for mid-range vision, finally to the bottom portion for near-vision or reading.

  
  
  
  

  The lens height for any Progressive lens must be 30mm or greater.

   

  
  
• 1.61 Progressive (No-line Multi-Focal)

  1.61 Progressive (No-line multi-focal)

  
  
  

  This high-index lens is a thinner, lighter lens than low- or mid- index, for use with strong prescriptions.. High-index lenses are those above our lower-index lenses, and are made with special lens materials that bend light more efficiently than lower index lenses.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  

  Progressive lens design includes three fields of vision, without lines, and is sometimes referred to as a "no-line bifocal". 

   

  In a progressive lens, the top portion corrects for distance-vision, narrowing to the lower middle for mid-range vision, finally to the bottom portion for near-vision or reading.

  
  
  

  The lens height for any Progressive lens must be 30mm or greater.

  
  
  
  
  
• 1.67 Progressive (No-line Multi-Focal)

  1.67 Progressive (No-line multi-focal)

  
  
  

  This high-index lens is a thinner, lighter lens than low- or mid- index, for use with strong prescriptions. High index lenses are those above our standard index lens, and are made with special lens materials that bend light more efficiently than lower index lenses.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  

  Progressive lens design includes three fields of vision, without lines, and is sometimes referred to as a "no-line bifocal". 

   

  In a progressive lens, the top portion corrects for distance-vision, narrowing to the lower middle for mid-range vision, finally to the bottom portion for near-vision or reading.

  
  
  

  The lens height for any Progressive lens must be 30mm or greater.

  
  
  
• 1.57 Photochromic + Progressive - Grey

  1.57 Photochromic + Progressive - Grey

  
  

  A 1.57 mid-index lens is thin and light, and is appropriate for most low- and mid-strength prescriptions.

  
  

  Photochromic lenses gradually darken outside in sunlight to become sunglasses. The lenses darken according to the amount of sunlight hitting the lens, and when moved indoors out of the sunlight, the lens returns to clear. 
  
  

  Progressive multifocal lenses include three fields of vision, without lines, and are sometimes referred to as "no-line bifocals". 

   

  In a Progressive lens, the top portion corrects for distance-vision, narrowing to the lower middle for mid-range vision, finally to the bottom portion for the near-vision or reading.

  
  

  The lens height for any Progressive lens must be 30mm or greater.

  
  
  
• 1.61 Transitions® Photochromic + Progressive - Grey

  1.61 Transitions® Photochromic + Progressive – Grey

  
  
  

  A thinner, lighter lens than low- or mid- index, for use with strong prescriptions. High index lenses are those above our standard index lens, and are made with special lens materials that bend light more efficiently than lower index lenses.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  
  

  Transitions® lenses contain patented photochromic dyes which cause the lens to activate - or darken - when exposed to ultraviolet (UV) rays from sunlight. When the UV light diminishes, the lenses fade back to clear. As outdoor light conditions change, the level of darkness adjusts, creating just the right level of tint and allowing just the right amount of light to enter the eyes at any given time. This action allows Transitions® lenses to help protect your eyes from the light you can see - reducing glare, diminishing eye strain and fatigue and enabling you to distinguish contrast more easily.

  
  
  

  Progressive lens design includes three fields of vision, without lines, and is sometimes referred to as a "no-line bifocal". 

   

  In a progressive lens, the top portion corrects for distance-vision, narrowing to the lower middle for mid-range vision, finally to the bottom portion for near-vision or reading.

   

  The lens height for any Progressive lens must be 30mm or greater.

  
  
  

  PLEASE NOTE: Photochromic lenses cannot be tinted.

  
  
  
• 1.67 Transitions® Photochromic + Progressive - Grey

  1.67 Transitions® Photochromic + Progressive - Grey

  
  
  

  A thinner, lighter lens than low- or mid- index, for use with strong prescriptions. High index lenses are those above our standard index lens, and are made with special lens materials that bend light more efficiently than lower index lenses.

  
  

  Your eyeglass prescription determines if a high-index lens is appropriate for your glasses and what type is best.

  
  
  

  Transitions® lenses contain patented photochromic dyes which cause the lens to activate - or darken - when exposed to ultraviolet (UV) rays from sunlight. When the UV light diminishes, the lenses fade back to clear. As outdoor light conditions change, the level of darkness adjusts, creating just the right level of tint and allowing just the right amount of light to enter the eyes at any given time. This action allows Transitions® lenses to help protect your eyes from the light you can see - reducing glare, diminishing eye strain and fatigue and enabling you to distinguish contrast more easily.

  
  
  

  Progressive lens design includes three fields of vision, without lines, and is sometimes referred to as a "no-line bifocal". 

   

  In a progressive lens, the top portion corrects for distance-vision, narrowing to the lower middle for mid-range vision, finally to the bottom portion for near-vision or reading.

  
  

  The lens height for any Progressive lens must be 30mm or greater.

   

  
  
  

  PLEASE NOTE: Photochromic lenses cannot be tinted.

  
  
  

PUPILLARY DISTANCE

The PD or Pupillary Distance is the distance between the pupils of the eyes, center to center, in Millimeters.(1 inch= 25.4mm). Unfortunately many optometrists leave this quite necessary measurement off of prescriptions, but it can be measured at home.

The best way to have a PD measured is by an optometrist, but you can have a friend measure it for you by holding a ruler just under your eyes and measuring the distance from the center of one pupil to the center of the other. You should be looking straight forward, fixing your focus on a distant object and not on the person measuring you. Repeat the measurement a few times for consistency.

Most people have a PD measurement that falls within the 54mm to 74mm range. If you are coming up with a number outside of this range consider that you might be making a measurement mistake. Do NOT just guess, and DO NOT try to measure your old glasses to determine this number. The PD is NOT measured from the geometric center of the lens and is not a visible spot on the lens.

Sometimes a prescription lists two numbers, written as PD 65/62 for example. 65 is the distance-vision PD, and the one to be entered on our forms.  The second number, 62 is the "reading" or "near-vision" PD, to be used ONLY if you are ordering single-vision reading glasses.

Occasionally a PD is written as for example, 32/34.5 which are the mesurements from the center of the nose to either eye. The PD is the sum of the two, 32+34.5=66.5 One can enter this as 66 or 67; either is appropriate.

You should also be able to get your PD from your previous eyeglass supplier. This figure does not expire with age, and they must give it to you as it is part of your full prescription. It is your property.

Extra Strength Charges

Extra strength means the prescription entered contains values stronger than the standard limits for that lens. For production of these lenses, the glasses must go to our Custom Lab for special processing and can take approximately five days longer to deliver.  There is an additional fee for these special lenses, the amount of which varies according to the type of lens and/or the strength of the prescription.

ANTI REFLECTIVE COATING

Anti Reflective (AR) coating improves both the vision and the appearance of the glasses. It is a layered metal oxide coating applied to both sides of the lens that greatly reduces both the internal and external the reflections on the lens surface while allowing more light through the lens.

Internal reflections appear as rings that can make lenses look thicker while external reflections mask the eyes from others looking at you. Conversely the AR coating will make the lenses appear thinner while the greatly reduced reflections will make the eyes look natural and allow the lenses to disappear.

At night AR coatings are especially effective by considerably reducing the annoying glare, reflections and halos around lights, making it much more comfortable and safer for driving at night.

This is a permanent tint on the lens, not to be confused with the Photochromic lens which changes shade according to the amount of sunlight.

An 80% tint is a dark sunglass tint for bright outdoor conditions. We recommend the 80% Gray tint for most sunglass applications. 

A  50% tint is a medium-light sunglass tint that is not too dark to make it unusable indoors, while giving some medium/light sunshade protection outdoors.

A 10% tint is a very light cosmetic /fashion tint barely noticeable to the wearer, but provides a slight hint of color to people looking at the wearer.

All of our eyeglass lenses, tinted or clear, have full 100% UV protection built-in to protect the eyes from harmful sunrays.