How to Read an Eyeglass Prescription: SPH, CYL, AXIS and ADD Explained
- How to Read an Eyeglass Prescription: SPH, CYL, AXIS and ADD Explained
- What Is an Eyeglass Prescription?
- What the Main Prescription Terms Mean
- SPH (Sphere)
- CYL and AXIS
- ADD
- PD (Pupillary Distance)
- Choosing Lenses and Frames for Your Prescription
- When to Arrange a New Eye Examination
- Why Choose Vision Concern for Prescription Glasses?
- Related Vision Concern Services
- Frequently Asked Questions
- Can I use an old glasses prescription?
- Does a prescription tell me which frame to buy?
- What should I bring for new glasses?
- Book a Prescription and Frame Review in Kathmandu
- Turn this information into a personal eye-care plan
Quick answer: On an eyeglass prescription, SPH (sphere) is the main power: minus for short sight, plus for long sight. CYL (cylinder) and AXIS correct astigmatism, ADD is extra reading power for bifocals or progressives, and PD is the distance between your pupils. OD means right eye and OS means left eye.
Due an eye test? Book at Vision Concern Lazimpat, Boudha-Tushal or Makalbari (eye test NPR 400).
Your eyeglass prescription is a record of the lens correction measured for your eyes. Understanding the main terms can help you discuss suitable lenses and frames with an optical professional, but it does not replace an eye examination or fitting.
In Kathmandu and worried about your eyes?
Book an eye exam (NPR 400 ≈ US$3) with our English-speaking optometrists in Lazimpat, Boudha or Makalbari — exams by appointment; optical shops open daily 8 AM – 8:30 PM. Card & cash accepted.
What Is an Eyeglass Prescription?
It is a written result from an eye examination that describes the optical correction prescribed for each eye. It can include lens power, astigmatism correction and, when needed, extra near-vision power.
What the Main Prescription Terms Mean
SPH (Sphere)
SPH describes the main spherical lens power used for short-sightedness or long-sightedness.
CYL and AXIS
CYL records the amount of astigmatism correction. AXIS describes its orientation. These values work together and should be copied accurately when lenses are made.
ADD
ADD is additional near-vision power, commonly used for bifocal or progressive lens designs.
PD (Pupillary Distance)
PD helps position the lenses in relation to your eyes. Correct measurements matter particularly for higher prescriptions and progressive lenses.
Choosing Lenses and Frames for Your Prescription
Lens thickness, frame shape, optical-centre position and your everyday needs all influence comfort. People who work at screens, drive often, read extensively or use progressive lenses may benefit from a more detailed fitting conversation.
When to Arrange a New Eye Examination
Arrange a professional review if you notice a sustained change in clarity, persistent headaches with visual tasks, double vision, eye pain or a major change in your visual comfort. Do not rely on an old prescription if your vision has changed.
Why Choose Vision Concern for Prescription Glasses?
Vision Concern Eye Clinic & Optical provides eye-care and optical guidance in Kathmandu with three convenient branches: Lazimpat, Boudha–Tushal and Makalbari. Bring your current glasses and prescription so the team can discuss fit, lens choices and the appropriate next step.
Explore Vision Concern eye-care and optical services for eye examinations, prescription glasses, progressive lenses, contact lenses and more.
Frequently Asked Questions
Can I use an old glasses prescription?
An older prescription may no longer match your current visual needs. An eye professional can advise whether a new examination is appropriate.
Does a prescription tell me which frame to buy?
No. Frame selection also depends on fit, comfort, lens design and personal preference.
What should I bring for new glasses?
Bring your prescription and current glasses if available. This helps with comparison and fitting discussion.
Book a Prescription and Frame Review in Kathmandu
Visit Vision Concern or contact us on WhatsApp +9779841466716
Replies within minutes to arrange a visit at Lazimpat, Boudha–Tushal or Makalbari.
In Kathmandu and worried about your eyes?
Book an eye exam (NPR 400 ≈ US$3) with our English-speaking optometrists in Lazimpat, Boudha or Makalbari — exams by appointment; optical shops open daily 8 AM – 8:30 PM. Card & cash accepted.
Turn this information into a personal eye-care plan
If this topic relates to your symptoms or vision, book an eye assessment at Vision Concern. Share your main concern when booking so the team can confirm the appropriate appointment or referral.
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Yes. Many visitors, particularly from Bangladesh and West Bengal (Kolkata), come to Nepal for cataract, retina, or other eye surgery at a hospital and also want new glasses, a general eye exam, or contact lenses at the same time, before or after their procedure. Vision Concern is an optical and eye-examination clinic, not a surgical hospital, so we work alongside hospitals such as Tilganga: we are happy to see you for glasses, contact lenses, or a routine check-up either side of your surgical treatment elsewhere.
No conversion is needed. Eyeglass prescriptions from Germany, France, the UK, the USA, China, Russia, and almost every other country use the same international format, SPH (sphere), CYL (cylinder), and AXIS, measured in diopters. Our opticians read this directly, so you can bring your prescription paper, a photo of it on your phone, or simply your current glasses, and we will use the same values. If your prescription is more than a year or two old, we recommend a quick, free re-check before we make your new pair.
Yes. Above roughly 3,000 metres, UV exposure increases sharply because of the thinner atmosphere and reflection off snow, and ordinary sunglasses (category 2-3) do not block enough UV to prevent snow blindness (photokeratitis). We recommend glacier glasses or category-4 sunglasses with side shields, and can fit these with your own prescription if needed. Vision Concern offers ZEISS polarized, UV400-certified sunglasses with prescription lenses, which we can prepare before you set off on your trek.