At Lensplaza, your vision is central. From the moment you choose your new glasses, your unique sight values play an important role. This blog explains everything about reading your glasses prescription.

Why is the glasses prescription important?

Your glasses prescription (brilpas) is important because it contains essential information about your eyes, including your unique prescription and specific lens characteristics. Whether it's the type of glass, special coatings, or helpful extras like anti-glare coating, it's all documented there. If your glasses are lost or damaged, your prescription provides a quick solution.

What do the values on your prescription mean?

L and R: Left (L) and right (R) eye designations, as vision often differs per eye.

SPH - Sphere (lens strength): Indicates your vision correction in diopters. A minus value (-) indicates nearsightedness (myopia); a plus value (+) indicates farsightedness (hypermetropry).

PD - Pupillary distance: The distance between pupils in millimeters, crucial for proper lens alignment.

As/AX and CYL: For astigmatism cases, As indicates the axis orientation in degrees; CYL describes corneal curvature.

ADD - Addition value: Used for multifocal or reading glasses, indicating additional diopters needed for presbyopia.

Other abbreviations on your prescription

• PRISMA: Prism correction for eye alignment differences

• BASIS: Prism base direction

• DIA (Diameter): Lens diameter

• SEG (Segment): Bifocal/trifocal lens positioning

• UV: Ultraviolet protection

• AR/HC: Anti-reflection or hard coating

• DBL: Distance between lenses

• BVD: Distance between eye and lens

• HSA/HFA: Multifocal lens positioning values

How to read your glasses prescription

Reading your prescription involves understanding each component. The sferische (SPH) value shows whether you're nearsighted or farsighted. CYL and AS values address astigmatism, with cylinder value indicating severity and axis showing orientation. L and R identify each eye. PD ensures proper lens alignment. ADD values are necessary for multifocal lenses.

Frequently Asked Questions

What does a spherical value of 0.25 mean?

Spherical values appear in 0.25 increments. A 0.25 value represents light correction. A plus (+) indicates mild farsightedness; minus (-) indicates mild nearsightedness.

Which prescription values matter for contact lenses?

SPH (spherical), CYL (cylinder), and AS (axis) values are important, especially for astigmatism. Contact lenses require special measurements like base curve (lens curvature matching corneal curve) and diameter for proper fit. Important: Glasses and contact lens prescriptions differ fundamentally.

Why is visual acuity sometimes expressed as a percentage?

Visual acuity percentages represent how well someone sees compared to "normal" vision at 100%. This simplified measurement shows letter or symbol recognition at fixed distances and isn't standardized across all tests.