Many people had a common opinion that there is no need of a prescription for the contact lenses as they are round enough and can fit any kind of eye. But, this is wrong. Even though all the eyes seem alike to see there are different sizes and shapes in the eye which make the measurement of the lenses different for different eyes. Also in order to get the right size of lenses and to ensure proper fitting the doctor will take the measurements of the eyes before preparing the prescription. Just like proper measurement is required for getting a proper pair of shoes, one needs a proper measurement for getting lenses and some times the measurements varies from one eye to the another of the same person.

The doctor will measure the surface of the eye and its curvature using special devices and also takes the photographs of the eye in close mode. The instruments passes a light ray in to the eye and the measures the reflections of the light from the cornea, based on which the curvature of the eye and the size of the contact lenses is calculated.

If there are any other vision disorders apart from the normal sight, more detailed measurements will be taken and the required lens will be customized according to the measurements. Moreover, the size of the pupil and the diameter of the iris of the eye will be measured to ensure proper fit and sizing.

After taking all the measurements the doctor will give you trail contact lenses and observe the fitting of the lenses with bio microscope which magnifies the cornea and provides a clear larger view. You will be asked to wear the contact lenses and to keep them for 15 minutes in order to allow them to settle and the natural tearing to stop. Later, the doctor will again check the eye condition and the fit of the lenses and tries to write a final prescription when he thinks that the trial lenses suited the eye well. In case, if the patient feels uncomfortable and the doctor sees any signs which say that the lens did not fit properly, then he will get new sized lens and repeat the same process. Mostly, fitting takes two visits after which the final prescription is given.