So long as your
refractive error (the amount of correction) must not exceed +5.00 to -5.00 dioptres in the most ametropic meridian (the worst axis - taking into account any astigmatism). Astigmatism must not exceed 2.00 dioptres. The difference in correction between each eye (anisometropia) must not be more than 2.00 dioptres. Your optometrist will be able to explain these terms.
You may wear contact lenses as a professional pilot (but not to correct near vision). If you do wear contact lenses, you should bring a report to your Class 1 examination from an optometrist, which includes the following:
your contact lens specification and corrected visual acuity;
confirmation that you have worn your contact lenses constantly and successfully for over eight hours a day over a period of at least one month.
All gas permeable and hard contact lenses must be removed at least 48 hours before the initial Class 1 medical examination. Any contact lenses should be brought to the examination. Multifocal contact lenses are not acceptable for Class 1 certification.