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’.
The eyes work by capturing an image and sending the image to the brain where it can be interpreted. So, if there’s a flower in front you, your eyes need to see a clear image that they can send to the brain, otherwise the brain has trouble figuring out what it is.
Your eyes need to bend light, in other words, to refract light, so that the image can be focussed and seen as clearly as possible. If a person can’t see clearly, it’s usually because their eyes aren’t refracting light properly. If your eyes are unable to refract light to the correct part of the retina you may be prescribed glasses that will help to do this for you. This will enable your brain to receive the information required and help you to process what you are looking at.
Does wearing the wrong prescription or strength damage your eyes? You’d be surprised to know this is a myth. Yes, it feels strange and may even give you a headache but wearing the wrong prescription number does not usually permanently damage your eyes.
Having said that, you should definitely get your vision checked if you are getting regular headaches or if the image is blurry when you wear your glasses. On some occasions your eyes will need to adjust after you get a new pair of glasses. You may find that your vision is slightly distorted when you put them on initially. However, if this lasts for 2 weeks or you experience any severe distortion or symptoms you should book an appointment and visit your optician. If blurred vision is accompanied by dizziness and headaches then contact your optician before the 2 weeks are up.
There are lots of charities that will take your old glasses and give them to people that need them. Charities will take your old glasses so that they can be reused by someone in a developing country. You could also drop your old glasses to any Vision Express store and we’ll make sure they’re put to use again.
If you would like to recycle your glasses the traditional way you would simply need to take them apart. If your lens is made of glass they will need to be separated from the frame and put with your other glass recyclables. If your frame is made of plastic it will go with the plastics. Any metal screws, or if you have a metal frame would need to go with other metals as well.