Decoding Prescription Terminology: SPH, CYL, & AXIS Explained

When you receive your eyeglass prescription, it can feel like decoding a secret message. Terms like SPH, CYL, and AXIS may leave you scratching your head. Fear not! In this blog post, we will demystify these common prescription terminologies, helping you understand their significance in your vision correction. Let's dive in!

1. SPH (Spherical):

The SPH refers to the spherical power of your prescription, which corrects nearsightedness (myopia) or farsightedness (hyperopia). Measured in diopters (D), a negative SPH value indicates nearsightedness, while a positive value signifies farsightedness. The higher the number, the stronger the prescription.

Understanding the SPH value is crucial for ensuring clear vision. If you have difficulty seeing objects in the distance or up close, your SPH value will indicate the necessary strength for optimal vision correction.

2. CYL (Cylinder):

The CYL value accounts for astigmatism correction. Astigmatism occurs when the cornea has an irregular shape, causing blurred or distorted vision. The CYL value, measured in diopters (D), indicates the degree of astigmatism correction required.

Astigmatism can cause blurry vision at various distances. With the CYL value, your eyewear specialist can tailor your lenses to correct this condition, providing you with sharper, more focused vision.

3. AXIS:

The AXIS measurement specifies the orientation of the astigmatism correction. It is measured in degrees, ranging from 0 to 180. The AXIS value guides the optical technician in placing the cylindrical correction on the lens to align with the astigmatism precisely.

Knowing the AXIS value ensures that your lenses correct astigmatism at the correct angle, leading to improved clarity and sharper vision.

Understanding the SPH, CYL, and AXIS values in your eyeglass prescription is vital for accurate lens production and optimal vision correction.

The SPH corrects nearsightedness or farsightedness, while the CYL addresses astigmatism. The AXIS value ensures precise alignment of the cylindrical correction.

By familiarizing yourself with these terminologies, you'll be better equipped to communicate with your eye care professional and ensure the creation of lenses that cater to your specific visual needs.

Remember, your eyeglass prescription holds the key to clearer, more comfortable vision. Embrace the knowledge and take control of your visual health!