Frequently Asked Questions:
Frequently Asked Questions about Prescriptions:
How do I read my eyeglass prescription?
How do I know my prescription order will be right?
What is a PD (Pupilary Distance) Measurement?
What do I do if my prescription has expired?
Is an Eyeglass prescription the same as a Contact Lens prescription?
Do you Accept Vision Insurance Plans?
What happens if my doctor changes my un-expired prescription?
Do I Need a Prescription if I'm only ordering Readers?
Which Lens Coatings and Treatments do you offer?
How do I know my Progressive (Bi-Focal) Lenses order will be accurate?
What are the best lenses for my prescription?
Can you prescription these sunglasses?
Are there extra fee's for my prescription lens request?
How do I read my contact lens prescription?
How do I know if my prescription has expired?
Why do you ask for my Date of Birth?

How do I read my eyeglass prescription? TOP

It is not necessary to understand your eyeglass prescription, however can be helpful when ordering/selecting the right products for your order. We verify prescriptions through your eye doctors office before processing your order(s).

Please review the examples below to understand your prescription.


Examples Explained:

Example #1: Single vision prescription is shown here. There is astigmatism in the right eye only.

Example #2: Bi-Focal / Progressive prescription is shown here. The '+2.00' ADD power is for standard (lined) Bi-Focal's and the 'PAL' is only for Progressive Bi-Focal lenses. If there is no 'PAL' on the prescription, then in most cases the ADD power can be used for lined Bi-Focal's or Progressives.

Example #3: This prescription shows a prism is required. The prism is different for each eye. According to the prescription, it would be 1.0 diopters 'Base-Up' for the right eye and 2.0 diopters 'Base-Out' for the left eye.

Example #4: This example shows how a distance + bi-focal/progressive prescription can be translated into a near-vision only prescription, in case the customer would like reading-only glasses using the 'Near' prescription shown here.

Example #5: In some cases, the copy of the prescription will not have the grids laid out. If this is the case, this example shows how to read & co-relate the fields to the normalized prescription format.


O.D.: Right Eye

O.S.: Left Eye

O.U.: Both Eyes

D.S.: Diopters Sphere, meaning there is no Cylinder (CYL) power in the eye.

SPH.: Sphere; Is the prominent strength in an eyeglass prescription. Doctor's have a tendency to sometimes write the numbers/parameters a bit differently. In the particular example, the Sphere would be read & normalized as '-0.50' for both eyes. You may sometimes see 'SPH', 'PL' or 'PLANO' written in this field by the doctor, which would simply mean there is '0.00' power in that section.

CYL: Cylinder; The amount of astigmatism. In some cases the doctor will write 'DS' or 'SPH' in this section, which would simply mean to leave the field empty or have '0.00' power in that section.

AXIS: Comes hand in hand with the CYLINDER, If there is no Cylinder, then there should not be any Axis. It's a degree/angle, therefore, it would be a value of or between 1 to 180. The reading from the example shown to the left would be '145' for the Right Eye (O.D.) and '15' for the Left Eye (O.S.). When there is a Cylinder and no Axis, this means usually that it is a 0 value axis, which in this sense would be a 180 degree axis.

ADD: How much power gets added to the distance Rx, for your reading-only Rx or for the bottom half of your bifocals/progressives

PL or PLO: Plano; This is a placeholder for the number '0'. This may also be left empty.

PRISM: This field is rarely used, therefore, it is not shown on the website. However, if you do happen to have a Prism, we will notice it when we verify the prescription. There are two separate parts to a Prism, the first being the diopter strength ('1.5') and the second being the direction ('BU'). There are four different directions: Base-Up, Base-Down, Base-In and Base-Out, however, these are commonly abbreviated as BU, BD, BI and BO. Prism can be applied to any prescription lens for an additional fee of $10 per diopter.

BASE: Base is used for Prism's, however, most of the time the Base is included in the Prism section. Please see the Prism section above for a further explanation of 'BASE'

NV or NVO : Near-vision or Near-vision-only; your doctor is recommending "reading-only" glasses.

P.D. or PD = pupilary distance (the distance in between your right pupil and your left pupil), in millimeters (mm). View more information about PD Measurements

Seg Height = This is the vertical measurement used for Bi-Focal / Progressive lenses. View more information about Seg Height Measurement & our in-house formula.


1. No Decimal Points?
If your prescription does not show decimal points, then it may be read as follows:
-100 = -1.00
+25 = +0.25

2. Blank Fields?
There may be blank fields in your prescription. In most cases there is not a mistake. Only fill-out the fields which are filled-out on the prescription and leave the rest blank.

Related Question(s):
Are there extra fee's for my prescription lens request?
How do I read my contact lens prescription?

How do I know my prescription order will be right? TOP
At, we handle each order with intensive care. All prescription orders are verified with your doctor's office prior to processing and inspected prior to shipping.
Related Question(s):
How can I submit my Prescription?
Will my information be kept private?

What is a PD (Pupilary Distance) Measurement? TOP
  Pupilary Distance is the measurement from the center of the left pupil to the center of the right pupil in millimeters and abbreviated "PD". A pupil would be most easily explained as the black dot in your eye. A prescription order may be initially placed without a PD measurement, however our lab cannot complete the order until the PD is submitted. PD measurements are required to ensure your lenses are properly installed in the frames to match your pupil.

Examples below:

In this example you will find that the person's PD measurement is 58 millimeters.

Types of PD's:

Binocular PD: The complete PD measurement.
Monocular PD: 2 numbers. A partial PD measurement, from the center of the face to the pupil. When the monocular PD's are added together, they should total up to the Binocular PD.
Near PD: The near PD is usually around 2-3 mm's less than the distance PD measurement. Considering the pupils will be usually closer since reading-only is for closer objects.

Examples of different types of PD measurements are below:

Did you know?

1 centimeter = 10 millimeters
1 inch = 25.4 millimeters

How can I get my PD Measured?
Below are tips on how to have your PD measurement obtained. PD information is not necessarily recorded on your prescription, and in most cases is available if eyewear was purchased through your doctors office.

1. Call the last place your prescription glasses were made/crafted. This information is usually kept on file at the store that previously filled your prescription glasses. You may choose to have us contact the store/office for you, please provide us with the telephone number after you place your order.

2. You can visit the prescribing eye doctors office and ask them to take this measurement for you.

3. You can visit a local optical store and ask them to take this measurement for you.

4. As a last option, and not recommended, have a friend measure it. Please do it a few times for a consistent reading.

What do I do if my prescription has expired? TOP
  We are not able to fill any prescriptions that have expired with a couple of exceptions: Your existing frames with lenses have broken, or your doctor gives you a prescription extension. We must verify these exceptions through your doctor.

Is an Eyeglass prescription the same as a Contact Lens prescription? TOP
  No. An eyeglass prescription is different than a contact lens prescription and cannot be used for a contact lens order and vice versa. If you do not have a prescription for one or the other please consult with your eye doctor.

Do you Accept Vision Insurance Plans? TOP
  No. However, an online receipt is provided upon order completion which may be submitted to your insurance company as an 'Out of Network' purchase. Please consult with your insurance provider for types of allowed reimbursements. Many vision insurance companies are now accepting 'Out of Network' purchases due to affordable prices found outside of optical shops.

What happens if my doctor changes my un-expired prescription? TOP

Your un-expired prescription may be corrected by your doctor if you are experiencing vision problems with your new lenses. You have 90 days from placing your order to have us re-do your lenses at no charge if an un-expired prescription update is required by your doctor. They must be the same lens material/brand used in your original order. Please see our Returns Section for more information.

Do I Need a Prescription if I'm only ordering Readers? TOP
  You may order readers that function the same as "over the counter" readers without a prescription. Please follow the steps below for instructions on how to order a pair of readers that function like "over the counter" readers:

1. Click 'ADD LENSES TO THESE FRAMES' on the order page of the frame which is desired. Click here fore more help with this step.
2. Select 'Single Vision' lenses as the lens type on 'STEP 1' of the lens ordering section.
3. Select the lens which you would like.
4. As the Patient's Name you must enter 'Readers' and the PD (Pupilary Distance) field must be left blank, as it will be manufactured like 'over the counter' readers.
5. The 'SPH' field is the only field required for this request. A plus (+) power is required and both eyes must have the same value.
6. All other prescription fields may be left blank.

Which Lens Coatings and Treatments do you offer? TOP

Many of the lenses purchased will include the common lens treatments, such as UV Protection and Scratch Guard.  If they do not, the prices for the treatments are additional, as follows:

General Coatings:

  • Scratch Guard: $7 additional
    Scratch guard helps prevent minor scratches.

  • UV Protection: $7 additional
    Protect your eyes against the suns harmful rays with 100% UVA / UVB protection.

Anti-Glare Coatings:

  • Generic: $29 additional
    Stock coating from the lab.  Great value.

  • Zeiss Carat®: $49 additional
    Advantage coating takes ease of cleaning to the new levels. In addition to the anti-reflective and scratch protection properties of traditional Carat®, the new hydrophobic finish makes lenses more smudge resistant and easier to clean than ever before.

  • Crizal®: $69 additional
    Crizal lenses are designed with two-sided scratch resistance, making them tough, durable and long-lasting. Dramatically reduce distracting double images and wear on your eyes created by headlights from other vehicles and streetlights. Advanced hydrophobic property that makes cleaning a breeze.

  • Crizal Alizé®: $79 additional
    Lenses resist dirt and smudges for even clearer vision. Scratching is reduced because lenses require less cleaning. Dirt and other contaminants wipe off effortlessly. The amazing properties fill in and smooth out the microscopic pores on the lens surface. Grime, dirt and oil essentially slide right off, making Crizal Alizé lenses ten times easier to clean than standard anti-reflective lenses.

Color Tinting:

Note: Additional tinting cannot be applied to polarized or sun-sensitive lenses (Transitions, etc.)


TINT DARKNESS: (80% is the maximum and is standard in most sunglasses)


  • Solid Color: $7 additional
    The entire lens will be one solid color of your choice.

  • Gradient: $15 additional
    The Lens will fade from top of the lens with the color of your choice and faded downwards to clear.

  • Double Gradient: $25 additional
    Two colors will be selected, the top color will fade into the lens from the top and the bottom color will fade into the lens from the bottom.

How do I know my Progressive (Bi-Focal) Lenses order will be accurate? TOP
  Our lab has over 40 years of optical experience with crafting progressive lenses. We use an advanced progressive formula which is precisely calculated to the frames you select in your order. The measurement generally used when making progressive/bi-focal lenses is the Seg. Height measurement, which is the vertical measurement of where the different powers will meet and/or graduate.

The Seg. Height (vertical measurement) of the lens is calculated by a formula which is for bi-focal, tri-focal and progressive lens requests. If a Seg. Height measurement is available that you would like for us to use, then you can provide this information in the 'Comments Section' of your order during check-out, and we will process this for you accordingly. Please ensure that if you are providing a Seg. Height measurement, then it must be the same measurement used for the same exact eyeglass frames (same size as well) that you're purchasing from us, since the Seg. Height measurement is dependant on the frame size. If a Seg. height measurement is not provided by the customer or their eye care provider(s), then we will use our in-house formula for making the progressive lenses in your order. Our in-house formula is accurate in most cases.

If you feel the progressive/bi-focal lenses and seg height was improperly made, then we can remake the lenses one-time at no cost to you. If a seg height re-do is requested, then the you must either provide the new seg height measurement to be used or mark on the lens where your eye (pupil) see's through the lens using a marker (permanent is ok), so our lab can remake them at the proper seg height for you.

Please review our Returns Section for more information on re-do requests.

What are the best lenses for my prescription? TOP
  The 'Best' lenses for you depend upon your needs. Standard recommendations* are listed below:

Lens / Coating For Who/What? Why?
Polycarbonate Children Impact Resistant, Light-Weight
Polycarbonate Activity / Sports Impact Resistant, Light-Weight
Polarized Sunglass Lenses Removes Glare off of Surfaces & Objects
Transitions Sun-Sensitive Lenses Versatile. Clear indoors and tinted outdoors.
Varilux Progressives Progressive Lenses Low Distortion. Better Vision.
Hi-Index 1.56 Prescriptions no greater than +/- 2.00 Thin
Hi-Index 1.60 Prescriptions no greater than +/- 4.00 Thin
Hi-Index 1.67 Prescriptions no greater than +/- 6.00 Thin
Hi-Index 1.70 Prescriptions +/- 5.00 to +/- 8.00 Thin
Hi-Index 1.74 Prescriptions +/- 5.00 to Any Thin as Possible
CR-39 Plastic Color Tinting & Gradient Tinting for Sunglass or Fashion lenses. Easiest material to tint
Anti-Glare Coating Progressive lenses or Strong Prescriptions (over +/- 2.00) Helps reduce distortion caused by light radiance.
10% Rose Color Tint For Reading / Near Vision / Computer lenses Helps eyes when reading.

*Recommendations are general and not recommended for everyone. For the best lens recommendations please consult with your eye doctor.

Can you prescription these sunglasses? TOP
  If the 'ADD LENSES TO YOUR FRAMES' button appears on the order page, then the frames can most likely accept your prescription lens request.

Prescriptions over +/- 2.00 are not recommended for curved or wrap-around styles. A flatter frame style is suggested for stronger prescriptions to help avoid distortion and vision warping (coke-bottle effect). You may find the following examples helpful when selecting frames:

Are there extra fee's for my prescription lens request? TOP
  Not all frames are the same and may require a custom lens. Custom lenses may require additional fees due to materials and/or labor. While reviewing your order we may determine that a custom lens order is required. If this happens, we will inform you immediately of any additional fees and you will have the option to confirm or cancel your order. Not all lens requests are guaranteed. We have the right to reject orders if we feel that the fit will be inaccurate.

How do I read my contact lens prescription? TOP
Contact Lens Prescription help

The contact lens prescription will include the lens brand along with the paremeters, such as power, base curve and diameter and any additional fields, such as Cylinder, Axis and Add power. cannot alter a patient's prescription with-out the prior written consent from the eye doctor's office. There may only the circumstance of altering the lens brand of a contact lens due to 'Signature & Private' label, which is explained below.

Signature & Private Brands
Sometimes lens manufacturers sell a particular lens under multiple brand names: for example, they may create private-label brands for large eye care practices or specific optical chains only. If your prescription calls for a private-label lens, we will change the order to the alternate brand name which will have the same lens, just different packaging.

Incomplete Prescriptions
Many times the doctor does not write out the entire contact lens prescription, such as the base curve and diameter. However, the online contact lens order form will guide you to the available options in which the lens is manufactured in. Most of the time each type of lens is made in 1 base curve and diameter.

Non-Matching Base Curve & Diameter
Many times the doctor does not write the correct base curve and/or diameter of a particular lens brand on the patient's prescription. The lens brand is manufactured in one particular range of these measurements only, therefore, this may confuse customers/patient's. In any case, the prescription will be verified prior to processing, therefore, you may rest assured that the proper contacts will be sent to you.
Related Question(s):
How do I know my prescription order will be right?
How do I read my eyeglass prescription?

How do I know if my prescription has expired? TOP
  Most prescriptions have an expiration date of 1-2 years. Expiration dates should be stated on your original prescription. If there is no date stated on your prescription, please contact the prescribing doctor for validity. We verify all prescriptions.

Why do you ask for my Date of Birth? TOP
  In order to verify your prescription we require your date of birth. We are required to verify all prescriptions by law.
Related Question(s):
Will my information be kept private?
What are your security standards?

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