You can find out if you have long-sightedness by having an eye test at your local opticians.

Find an opticians near you .

Having an eye test at least every two years is usually recommended, but you can have a test at any point if you have any concerns about your vision.

For some people such as childrenunder 16, orthose under 19 and in full-time education eye tests are available free of charge on the NHS.

Read about NHS eyecare entitlements to check if you qualify.

What happens during an eye test

Your eyes will usually be tested byan optometrist (someone who's been specially trained to examine the eyes).

A number of different testsmaybe carried out as part of your eye test, possibly including:

  • measurements of the pressure inside your eyes
  • checks to measure how well your eyes work together
  • visual acuity tests where you're asked to read from a chart that has rows ofletters that getsmaller on each line
  • retinoscopywhere a bright light is shone into your eye to see how your eye reacts to it

If the tests detect a possible problem with yournear vision, you may be asked to repeat the visual acuity tests while different strength lenses are placed in front of your eyes.

This will help the optometrist to determine what your glassesprescription should be.

Understanding your glasses prescription

If an eye test finds that you're long-sighted, you'll be given a prescription that describes what lenses you need to improve your vision. This can be used to make glasses or contact lenses.

Your prescription will usually consist of three main numbers for each eye. These are:

  • Sph (sphere) a positive number here indicates that you're long-sighted, while a negative number indicates that you're short-sighted
  • Cyl(cylinder) this number indicates whether you have Astigmatism (where the front of your eye isn't perfectly curved)
  • Axis this describes the angle of any astigmatism you have

If you're long-sighted, the Sph number is the most relevant. This is given in a measurement called dioptres (D), which describes how severely long-sighted you are.

A score up to 3D is usually considered to be mild long-sightedness, while a scoreof more than 6D is considered to be fairly severe long-sightedness.

Content supplied by the NHS Website

Medically Reviewed by a doctor on 31 Aug 2016