WHAT IS REFRACTIVE ERROR?

EMMETROPIA (NO REFRACTIVE ERROR / "NORMAL EYE") THIS IS WHEN ALL RAYS OF LIGHT ARE FOCUSED BY THE CORNEA AND LENS PERFECTLY ON THE RETINA. DISTANCE AND NEAR VISION ARE BOTH SHARP.

MYOPIA (NEARSIGHTEDNESS) - THIS OCCURS WHEN THE RAYS OF LIGHT ARE FOCUSED IN FRONT OF THE RETINA. THIS CAUSES BLURRED DISTANCE VISION. NEAR VISION IS CLEAR BUT THE RANGE OF CLEAR NEAR VISION DEPENDS ON THE LEVEL OF NEARSIGHTEDNESS. NEARSIGHTEDNESS USUALLY OCCURS WHEN A PERSON'S EYE IS TOO LONG.

ASTIGMATISM - THIS OCCURS WHEN A PERSON'S CORNEA HAS THE SHAPE OF A FOOTBALL INSTEAD OF BEING PERFECTLY SPHERICAL LIKE A BASKETBALL. THIS CAUSES RAYS OF LIGHT PERPENDICULAR TO EACH OTHER TO BE FOCUSED DIFFERENTLY WITHIN THE EYE. ASTIGMATISM LEADS TO BLURRED, TILTED VISION.

HYPEROPIA (FARSIGHTEDNESS) - THIS OCCURS WHEN RAYS OF LIGHT ARE FOCUSED BEHIND THE RETINA. THIS CAUSES BLURRED DISTANCE VISION IF A PERSON IS UNABLE TO COMPENSATE BY INTERNAL FOCUSING. NEAR VISION IS BLURRED. FARSIGHTEDNESS USUALLY OCCURS WHEN A PERSON'S EYE IS TOO SHORT.

PRESBYOPIA (A NATURAL EYE CONDITION) - WHEN MOST PEOPLE REACH THEIR FORTIES, THEY HAVE TO HOLD PRINTED MATERIAL AT ARM'S LENGTH TO READ CLEARLY. THIS IS THE RESULT OF AN AGE RELATED CONDITION CALLED PRESBYOPIA.

PRESBYOPIA IS A UNIVERSAL CONDITION ASSOCIATED WITH THE EYES' DIMINISHING ABILITY OVER TIME TO FOCUS ON CLOSE OBJECTS. IT IS NEITHER A DISEASE NOR A DEFECT. PEOPLE USUALLY DISCOVER THIS TROUBLE DURING THEIR MID-FORTIES, AND CAN CORRECT IT WITH LENSES ADAPTED TO THEIR VARIUOS NEEDS. ALTHOUGH PRESBYOPIA IS A NATURAL CONDITION THAT EVERYONE HAS TO FACE SOONER OR LATER, PROPER DIAGNOSIS, EYE CARE, SAFETY PRECAUTIONS AND MONITORING OF THE CONDITION CAN GIVE OUR EYES A NEW LEASE ON LIFE!