What are the numbers on contact lenses?
The three main measurements on your contact lenses are power, base curve, and diameter.
- Base Curve. The base curve of the lens is marked as BC on most contact lens prescriptions. …
- The Diameter. The diameter of the lens is marked as DIA. …
- Power. …
- Glasses and contacts scripts are not the same.
Do contact lenses show prescription?
Contact lenses are prescription medical devices. Even if you just want to purchase cosmetic contact lenses that change your eye color, you will still need an eye exam and a prescription from an eye doctor.
How do I know my contact lense power?
You’ll find that the cylinder number on a contact lens prescription is always a minus number. This indicates the extra power you need for astigmatism correction. A higher number denotes a more severe level of astigmatism. The cylinder value for a glasses prescription on the other hand can be a plus or minus.
What do lens prescription numbers mean?
These numbers represent diopters, the unit used to measure the correction, or focusing power, of the lens your eye requires. Diopter is often abbreviated “D.” For example, if your prescription says -1.00, you have one diopter of nearsightedness. This is a fairly mild amount of nearsightedness.
What does D mean on contacts?
Sphere (SPH): The amount of lens power, measured in diopters (D), which corrects nearsightedness or farsightedness. If the number under this heading features a minus sign (–), this means you’re nearsighted; if it has a plus sign (+), this means you’re farsighted.
What is the difference between 14.0 and 14.2 diameter contacts?
14.0mm and 14.2mm contacts
In fact, there is not much difference between these two. Some manufacturers only make 14.2mm diameter contacts, and some others produce 14.0mm diameter contacts. … Many 14.0mm contacts users use 14.5mm or 14.8mm contacts to demonstrate dolly effects on their eyes.
How long does 1800 contacts take to verify prescription?
It may take up to 48 hours to process your order. We’ll verify your contact lens prescription with your eye doctor as soon as possible.
What is the new contact lens rule?
In service of patient choice, the FTC Contact Lens Rule requires eyecare providers who prescribe contact lenses to give patients a copy of their contact lens prescriptions at the end of a contact lens fitting—even if the patient doesn’t ask for it.
How do you read eye prescription for astigmatism?
If you do have astigmatism, a value will be entered in this box along with an Axis. E.g. Left eye: -2.25, Right eye: -2.25. Axis: Measured in degrees, this value is normally between 0-180 and is the direction where an extra power is added in the contact lens to correct your astigmatism.
What does 75 mean in eye prescription?
This second number, -0.75, indicates the person has an astigmatism, which is a distortion in the shape of the cornea that causes blurred vision. Not everyone has astigmatism, of course, so if the number wasn’t there, you’d see some letters – DS or SPH – to indicate that there is no astigmatism.
Is minus 3 eyesight bad?
Generally, the further away from zero (+ or -), the worse the eyesight. A number between +/-. 025 to +/-2.00 is considered mild, a number between +/-2.25 to +/- 5.00 is considered moderate, and a number greater than +/- 5.00 is considered severe. Eye prescriptions can change over time.
Is .75 eyesight bad?
For both types, the closer you are to zero the better your vision is. For example, even though measurements of -0.75 and -1.25 both qualify as mild nearsightedness, the person with a spherical error of -0.75 is technically closer to 20/20 vision without their glasses on.