Aberration – the result of refracted light failing to focus sharply
Accommodation – the process taken by eyes to adjust their power to maintain focus on objects as they move nearer, for example, to read.
AK (astigmatic keratotomy) – a surgical procedure for reducing astigmatism involving cutting the cornea so that it heals more spherical.
Amblyopia (lazy eye) – reduced vision in one or both healthy eyes that cannot be fully corrected using spectacles or contact lenses.
AMD or ARMD (age-related macular degeneration) – mostly affecting the over 60 age group, it is a deteriation of the macula area of the retina, resulting in a loss of central vision. Grouped as the far more common “dry” AMD, a slower deteriation whereby a yellow tissue (drusen) appears in the retina and rarer “wet” AMD, where fluid leakage from the rupturing of small, newly formed blood vessels quickly causes the loss of central vision.
Anterior Chamber – the area of the eye located in front of the crystalline lens and iris, and behind the cornea.
AR Coating (Anti Reflective Coating) – ultra thin chemical coating added to a lens surface to increase light transmission and reduce levels of reflection reaching the eye.
Aqueous Humour – clear fluid naturally produced in the eye providing nutrients and controlling intraocular pressure.
Aspheric (not spherical) – aspheric spectacle lenses have specially designed surfaces that flatten and thin lenses, plus reduce eye magnification and visual distortion in stronger prescriptions. Aspheric contact lenses ara able to correct low levels of astigmatism without the need to fit more complex toric lens designs.
Astigmatism – resulting in blurred vision due to two focal points, this condition is caused by an irregular cornea shape.
Aviator Glasses – originally the metal framed sunglasses worn by pilots, aviators have a large teardrop shape. The aviator style has evolved and comes in many materials and forms.
BCVA (Best Corrected Visual Acuity) – with correction such as contact lenses or glasses this is the best vision you can achieve.
Beta Titanium – a very strong and flexible titanium alloy.
Bifocal Lens – divided eyeglass or contact lenses with one part for near vision and one part for far vision.
Blepharitis Condition – symptoms include irritable eyes, burning, swollen eyelids and mucus particularly noticeable after sleep.
Bridge – the eyeglasses bar that crosses the nose.
Cable Temple – eyeglasses that fasten around the ear.
Cataract – clouding of the eye lens causing loss of clear sight. Corrective surgery replaces the eye’s natural lens with an artificial one.
Central Island – a laser eye surgery complication leaving an “island” of corneal tissue in the concave ablation zone. This can cause double vision as well as distortion.
Clip-on – glasses that attach to your regular glasses.
Colour Blindness – the inability to identify colours.
Computer Vision Syndrome – prolonged computer use may cause eyestrain, blurred vision, headaches and irritable eyes.
Conjunctiva – mucous membrane lining the eye and the eyelid surface.
Conjunctivitis – inflamed conjunctiva.Back Next