The vision regulations have changed for professional drivers who wear spectacles (not contact lenses) when driving. You now have to bring along to the medical assessment an opticians prescription which is dated within 4 months of the date of the medical. This needs to state the corrected and uncorrected visual acuity for us to enter the information into the eyetest section of the D4 Paperwork. The visual acuity is not your prescription and is not normally recorded on your prescription.
If you do not have one you can see an optician either before or after the medical who will complete the first page of the D4 form.