An Optician does many eye checks, testing vision, checking the health for eye diseases
and eye problems. Often use an eye test chart to check level of vision.
Eye Test Chart
In order to measure a persons level of vision, an eye test chart is used that often
starts off with larger letters . These gradually becomes smaller, requiring good
vision to see these. There are several different types of test charts. A common
one is called a Snellen chart (named after a Dutch Doctor).
If vision is poor, then the optician will aim to improve sight with lenses by further
You may have heard of twenty twenty vision,20:20. This means good standard of vision.
Usually the smaller rows of letters on the chart. Click for more information on test
Visual Field Test
Checks side vision with a machine and the procedure is called a visual field test.
This can detect eye diseases like glaucoma and even general disorders such as a stroke
where there can be abnormal visual fields, blind spots and defects.
There are many different types of field test machines.
Peripheral vision is the scientific term for side vision. This side vision helps
people to navigate in the real world and can lead to falls or accidents if there
are blind spots.
Puff of air machine
This measures the inside eye pressure and so is useful for detecting glaucoma eye
It releases a puff of air onto the eye and so tends to make most patients blink or
So not usually the patients favourite part of an eye test ! However it is not painful
and is over very fast.
Eye Health examination
Use of various instruments to analyse the external and inside the eyes for any diseases.
Usually a bright light is shone into the eye to check the health of structures such
as the optic disc, blood vessels, retina and natural lens. Cataracts can be detected
with this method.
Testing for glasses
Specialised glasses called a trial frame may be put onto your face that will allow
the optician to try different lenses. This can be bit heavy and looks bit like a
science fiction prop ! Or a head unit may be placed over face that covers the eye
which has the different lenses already in the unit.
History and Symptoms
Questions about your general health and history are asked, as well as any current
symptoms as they may have a bearing on which tests are done e.g. if suffering from
headaches or family history of glaucoma.
Checks for how well a person can use both eyes at the same time and to check for
eye movements in all directions. This is another large subject area called binocular
vision or orthoptics.
The 3D films work better if a person has normal binocular vision.
Many more tests may be done but this is a short overview.