Prescription glasses FAQs

Your eyes are a complex and sensitive part of your body so it’s no wonder you might have lots of questions related to your prescription glasses. In this frequently asked questions (FAQ’s) article we answer your queries about how your glasses work, how to interpret your prescription yourself, and how to recycle your glasses. Remember that you shouldn’t hesitate to contact us if you have any questions that you don’t see answered on our website.  

If you look at your glasses prescriptions, you may see a section for OS and one for OD and some numbers under the two. These are Latin abbreviations. OS (oculus sinister) is for the left eye, and OD (oculus dextrus) is for the right eye. Sometimes you might even see a section for OU. This would be information relating to both eyes collectively.

The further away from zero your number is, the greater the need for your vision to be corrected. The larger the number the stronger your prescription needs to be to in order to correct this.

  • A “plus” (+) sign indicates you are long sighted. (Reading)
  • A “minus” ( - ) means you are near or short-sighted. (Distance)

The unit to measure the corrective power of your glasses (dioptres) is represented by the letter ‘D’.