What do these numbers mean?

How to Enter my Glasses Prescription

This article will help you understand how to enter your glasses prescription when buying Specs Addict glasses online at www.specsaddict.com

SPHERE, CYL, AXIS, ADD, PD:

Enter the numbers from your prescription into the same fields shown on the prescription screen. Make sure you copy the “+” or “-” signs exactly as in the prescription.

If there is nothing entered in your glasses prescription under CYL, AXIS, or ADD then enter these fields as “0.”.

AXIS: This is a number between 0 and 180 representing an angle in degrees. Axis does not have a “+” or “-” sign in front of it.

If you do not see the words “SPHERE”, “CYL” or “AXIS” in your glasses prescription, please see the examples below to understand how to interpret the prescription.

ADD: If there is only one “ADD” on the prescription then it usually applies to both eyes, so write the same ADD into right and left eyes. (Sometimes this is written on your prescription as “Addition” or “Reading Addition”.)

“pl” or “plano”: This needs to be entered as 0.00 into the SPHERE field when ordering glasses. Handwritten glasses prescriptions usually use the word plano instead of the number 0. Plano means that you do not require a corrective lens in your glasses.

BAL: If you see the word “Bal” or “Balance” in the glasses prescription for one eye, then enter BAL as the sphere power for that eye. The word “Balance” or “Bal” is used to show that the prescription in that eye is not important, as the eye has no useful vision. When balance is entered then a lens of similar power to the good eye is used for the balance lens, this makes the glasses look “balanced”.

PD (Pupillary Distance): Enter into the fields of PD what is written on your prescription. PD is the distance between your pupils, from which we measure your lenses.

To find out more about PD and for information on how to determine your PD, see our What is PD section.

To measure your PD online using our specially developed free application, please click here.

If your PD is given separately for right and left eyes then add the right and left PD together to give the total PD. If the prescription gives only one number for PD then tick “My prescription contains only one PD” and enter the PD.

Notes: Please type any notes by the optometrist that are written on the prescription into the notes section.

Examples of Spectacle Prescriptions

Example 1:

PD: 65/62

R: +1.50 / -1.00 x 90
L: +1.75 / -2.00 x 95
Add: +2.25

You would enter this into the online prescription screen as shown below:
RIGHT:Sphere: +1.50 Cyl: -1.00 Axis: 90 Add: +2.25
LEFT:Sphere: +1.75 Cyl: -2.00 Axis: 95 Add: +2.25

Distance PD: 65 Near PD: 62

Exactly the same prescription may be written as:

R

L

Sphere

+1.50

+1.75

Cylinder

-1.00 x 90

-2.00 x 95

ADD:

+2.25

+2.25

PD:

32.5

32.5

NEAR PD:

31

31

In the prescription above the PD has been written separately for each eye. This is called monocular PD. To enter your PD into the prescription screen, add the right and left PD together to get the DISTANCE PD and add the right and left NEAR PD together to get the NEAR PD.

i.e.
DISTANCE PD = 32.5 + 32.5 = 65
NEAR PD = 31 + 31 = 62

Example 2:
R: -1.50
L: -2.00 / -0.50 x 180
PD: 57

The prescription above has no CYL or AXIS in the right eye. There is no Add. Enter the Cyl and Axis in the right eye as 0. Enter the Add for both eyes as 0.

Therefore, you would enter them into the online prescription screen as shown below:
RIGHT:Sphere: -1.50 Cyl: 0.00 Axis: 0.0 Add: 0.00
LEFT:Sphere: -2.00 Cyl: -0.50 Axis: 180 Add: 0.00

PD: 57

Example 3:

Hand-written prescriptions do not usually use the number 0. Instead the word ‘plano’, or the abbreviation ‘pl’ is used. If you see the the word “pl” or “plano” enter it as 0.
Hand-written prescriptions often have “DS” or “D” after the SPHERE power to show that there is no CYL.

Therefore, you would enter this into the prescription screen as shown below:
RIGHT:Sphere: 0.00 Cyl: -1.00 Axis: 180 Add: 0.00
LEFT:Sphere: +0.25 Cyl: 0.00 Axis: 0.0 Add: 0.00

PD: 67

Example 4:

The word “Balance” or “Bal” is used to show that the prescription in that eye is not important, as the eye has no useful vision.

Select BAL as the sphere power. The CYL and AXIS for that eye are then 0. Add can still be entered.

R: -1.50 / -0.75 x 65
L: Bal
ADD: +2.50
PD: 68/65

Therefore, you would enter them online into the prescription screen as shown below:
RIGHT:Sphere: -1.50 Cyl: -0.75 Axis: 65 Add:+2.50
LEFT:Sphere: BAL Cyl: 0.00 Axis: 0.0 Add:+2.50

Distance PD: 68 Near PD: 65

Example 5:

R: pl L: pl
ADD: +1.50
PD: 61/58

Enter Sphere: 0.00 in both eyes and Add: +1.50 in both eyes.

Therefore, you would enter this into the online prescription screen as shown below.
RIGHT:Sphere: 0.00 Cyl: 0.00 Axis: 0.0 Add: +1.50
LEFT:Sphere: 0.00 Cyl: 0.00 Axis: 0.0 Add: +1.50

Distance PD: 61 Near PD: 58

Example 6:

R

L

Sphere

-2.50

-3.00

Cylinder

-1.00 x 180

0.00 x 0.0

ADD:

0.00

0.00

PD:

31

31

NEAR PD:

0.00

0.00

The prescription above gives a monocular distance PD but it does not give near PD. Therefore tick “my prescription contains only one PD”.

Add the right and left PD to give the total PD. Enter the total PD (Binocular PD).

You would enter them online into the prescription screen as shown below:
RIGHT:Sphere: -2.50 Cyl: -1.00 Axis: 180 Add: 0.00
LEFT:Sphere: -3.00 Cyl: 0.00 Axis: 0.0 Add: 0.00

Distance PD: 62

Which lenses will Specs Addict use for your prescription glasses?

At Specs Addict we offer FREE prescription lenses included in the price of your frames. We are proud to deliver this impressive deal to our valued Addicts as we want you to be happy with your purchase and overall experience. As a general rule, the stronger your prescription the thicker the lens will be. This means that if you have a strong prescription, Specs Addict will have to use what is known as a “high index lens”. So if you require strong vision correction Specs Addict will supply you with a thinner lens so that you don’t look like you are peering out of old Coke bottles!

So, Specs Addict will provide you with free prescription lenses once you enter your prescription online, if your prescription is less than about -6. Minus 6 is a fairly strong prescription and our optician advices that it is best to avoid fitting a stronger prescription than minus 6 with the lenses that we include for free. This has nothing to do with quality and everything to do with delivering you the best quality lenses and ensuring the health and use of your peepers!

Most of Specs Addict’s customers do not require very strong vision correction, but of course, some do. If ythis applies to you this means that you will have to pay around and extra $70 for your lenses. A small price to pay for dashing eyewear, easily selected online. This additional cost is to ensure that Specs Addict can make lenses to support your strong prescription that are at the same time as thin as possible. Your new lenses will come with an anti-scratch, anti-reflective coating, which alone retails in excess of $150 (not including the cost of the lenses!).

At Specs Addict we’ve taken the guess-work out for you when it comes to choosing lenses for your prescription glasses.

Our Specs Addict website is specially designed to make things really easy for you. With just a few clicks you can figure out your lens needs based on your prescription details.

Below is information about the different glasses lenses offered by Specs Addict, which may help to understand differences between different ophthalmic lens types.

Glass Spectacle Lenses

Originally spectacle lenses were made from glass. Glass has the benefit of being very hard so it doesn’t scratch easily. However, glass has the disadvantage of being heavy and also easy to break. Serious eye injuries have resulted from glass lens breakage. Many people do not like heavy glasses pushing on their nose. Glass is difficult to work with for opticians as it can break whilse glasses are being made. Simply dropping spectacles cause glass lenses to break. Glass lenses offer very little protection against ultra-violet light. Glass is more expensive to manufacture than plastic. For these reasons glass lenses are rarely used these days. Specs Addict does not sell glass lenses.

CR-39 Plastic Spectacle Lenses

During the early 1960s a lightweight plastic spectacle lens called CR-39 (Columbia Resin #39) was developed. CR-39 lenses have a similar thickness to glass lenses. They don’t break as easily and they are lighter than glass. However, CR-39 lenses were originally easy to scratch. This initial problem was reduced with the development of hard coatings. A hard coating is a thin coating of a hard plastic on the lens surface which does not scratch as easily as the CR-39 lens. All lenses sold by Specs Addict are hard coated for you, free of charge.

CR-39 is the main lens material used today in ophthalmic quality plastic lenses. Ready-made reading glasses such as what you may buy from the chemist do not use CR-39 for the lenses. All standard plastic lenses sold by Specs Addict are hard coated CR-39.

If your eyes do not require much vision correction, Specs Addict will likely use CR-39 Plastic Lenses in your Specs Addict glasses.

Mid-Index Spectacle Lenses

With the constant advances in technology, newer plastic materials have been developed that are thinner and therefore lighter than CR-39.

The higher the refractive index, the thinner the lens can be. Mid-index lenses usually have a refractive index between 1.54 and 1.56, making them thinner than standard CR-39, but not as thin as high index lenses. Mid index lenses are appropriate to keep the lens thickness down for people who have a slightly higher than average refractive error.

When you enter your prescription on the Specs Addict website we will decide for you, based on your prescription, which lenses are most appropriate for your particular refractive error. These lenses will be made individually for you free of charge and fitted into your Specs Addict glasses.

High Index Lenses

For higher prescriptions even 1.56 lenses may look too thick and heavy. Lenses are available with a refractive index of 1.6 and 1.67. These lenses are referred to as high index lenses. The higher the index, the higher the price and this is why Specs Addict charge a small additional fee if you require strong refractive correction. The price charged by Specs Addict is well below the retail price and we include all anti-scratch and anti-reflective coatings for free.

Photochromatic Lenses

Photochromatic lenses change colour in response to UV light.

This means that they become dark in the sunlight and lighten up indoors. They become as dark as sunglasses outdoors and about half as dark as sunglasses when inside a car. Some examples of brands of photochromatic lenses are Transitions®, Sunsensors® and InstaShades®.

Photochromatic lenses block 100% of UV rays to protect your eyes from UVA and UVB radiation which could damage your eyes.

If you would like your Specs Addict glasses to be fitted with photochromatic lenses we can arrange this for you for only $100. These lenses usually retail at over $300.

Anti-Reflective Coatings

An anti-reflective coating (also called multi-coat) reduces the reflections visible on the lens surface.Specs Addict include anti-reflective coatings for FREE on all Specs Addict lenses.

Lenses with anti-reflective coatings are excellent for night vision as they reduce reflections caused by light reflecting off the lens surface. However, contrary to popular opinion they cannot reduce glare.

Anti-reflective coatings make glasses look better as the lens looks clear, rather than having visible reflections on it. This means people can see your beautiful eyes rather than the lens in front of those eyes.

Anti-reflective coatings consist of a very thin coating of material that absorbs light that would otherwise have been reflected. It is not possible to make lenses completely clear so often there is a very slight green or blue reflection visible.

Anti-reflective coatings used in the past were difficult to keep clean as dust and grease and fingerprints showed up very easily on them. Advanced hydrophobic anti-reflective coatings as used by Specs Addict are easier to keep clean.

Please refer to the How to Clean your Glasses article for more info on keeping your Specs Addict glasses clean.

UV Protection

All lenses sold by Specs Addict filter out most UV light. Prescription sunglasses are coated for FREE with UV filters to block all UV light.

Single Vision Lenses

Single Vision Lenses are lenses with only one optical power. These are often reading glasses or glasses worn all the time. Specs Addict specialises in single vision lenses because these are the types of lenses worn by 95% of our customers.

If you require bifocal or multifocal lenses we can arrange the production of these for you at very a competitive price, so please contact us.

Bifocal Lenses

Bifocal lenses have two optical powers. There is a line separating the two powers. The top section is usually for distance vision and the bottom section is usually for near vision.

If you require bifocal lenses for your Specs Addict glasses, please contact us and we will help you out with them.

Multifocal Lenses

(also called Graduated Lenses, Progressive Lenses or PAL – Progressive Addition Lenses)

These lenses’ optical power gradually changes to give a reading power at the bottom of the lens and the distance prescription at the top of the lens.

The fitting position of multifocal lenses needs to be accurately measured when the lenses are ordered. These measurements are different for every frame. For this reason Specs Addict does not sell multifocals.

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