What are the markings on my progressive lenses?
These are the marks left on the surface of the lenses during the processing. It is a standard industrial practice to engrave or etch these markings to align exactly where the point in the lens is that starts changing from your distance Rx to your reading Rx.
Why are there markings on my glasses?
Laser engravings in modern lenses are there to assess the centering of the lens in the glasses. Especially in progressive lenses, several engravings are placed in the lens by the manufacturer to provide the following information. All this information can be found by looking closely at the engravings.
Do varifocal lenses have numbers on them?
Every varifocal lens has a series of engravings on them to allow identification of model and manufacturer and allow the setup to be checked. Some are more obvious than others but you won’t see any of them when you are wearing the spectacles.
What does PAL mean on glasses prescription?
The progressive addition lens (PAL) is a spectacle lens design with progressive refractive power changes across the lens surface to provide sharp vision at different viewing distances for patients with reduced accommodative strength.
Why do my glasses have letters on the lenses?
all varifocal lenses nowadays, esp. the top brands have numbers and symbols laser engraved into the glass for identification and prescription verification. The “200” signifies that the power for the reading portion is +2 diopters over and above the distance power.
What are the numbers printed on my glasses lens?
1) The eye size number (it is the size of the lenses on your frame). 2) The bridge size number (the distance between the lenses). 3) The temple length number (it is the size of that part of your eyeglass frame, which rests upon your ears).
Why are there letters on my glasses lens?
How do you read PD on eyeglass prescription?
Close your right eye and align the ruler’s zero to the center of your left pupil. While looking straight, close your left eye and open your right eye. Read the mm line that lines up with the center of your right pupil. This number is your PD.
Why are there numbers on my prescription lenses?
Some of the numbers in your prescription tell the eyeglass manufacturer how much correction your vision needs. Eyeglass strength is measured in diopters. If your prescription reads -1.00, that means your eyeglasses need 1 diopter of strength to correct nearsightedness.
Why are there numbers in my lenses?
There are little markings on the lenses to allow the optometrist/dispensing optician to ‘mark up’ the lenses to check positioning. They are there so that they can be checked if there are any problems. Only a couple of other types of lens are marked in this way, and those are usually safety glasses.
How do I know if I have single PD or dual PD?
Dual PD is the measurement of the center of each pupil to the bridge of the nose. Single PD is the total distance between the center of both pupils.
Is OS Left or right?
They are Latin abbreviations: OS (oculus sinister) means the left eye and OD (oculus dextrus) means the right eye. Occasionally, you will see a notation for OU, which means something involving both eyes.
How can I tell my vision from my prescription?
You will see a plus sign or minus sign in front of your eyeglass prescription, and that number is shorthand for farsightedness or nearsightedness. A “+” means that you are farsighted (trouble seeing things close up). A “-” means you’re nearsighted (trouble with seeing far away).
What do numbers on the side of glasses mean?
The numbers beneath the frames reflect the SIZE MEASUREMENTS in millimeters (mm). THE FIRST NUMBER (ex.54) = the width of the lenses. THE SECOND NUMBER (ex.15) = the distance between the lenses. THE THIRD NUMBER (ex.140) = the length of the temple arm including the portion going behind the ear.
Where is the best place to buy varifocal lenses?
Quite simply – with the low prices we offer and the latest varifocal lens designs combined with our full money-back guarantee – Online Opticians UK is the best place to buy varifocal lenses. But remember, for total peace for mind, we offer our “no quibble 30 day, 100% money-back guarantee” on all purchases.
What are the different parts of a varifocal lens?
Near/Reading Zone: The ‘bottom/lower’ portion of the lens provides the ‘close up/reading’ area There are many different types of varifocals on the market offering numerous benefits and features dependent upon your lifestyle, needs and requirements.
Why do varifocal lenses have engravings on them?
Every varifocal lens has a series of engravings on them to allow identification of model and manufacturer and allow the setup to be checked. Some are more obvious than others but you won’t see any of them when you are wearing the spectacles.
What is the difference between a standard and premium varifocal lens?
They have minimal peripheral distortion and are easier to adapt to. This image shows the difference in the viewing field and distortion between a standard and a premium varifocal lens. The premium varifocal lens clearly having a wider field of vision and less peripheral distortion.