If a person is said to have cylindrical eye power, they have what is known as astigmatism, a refractive error. It means that the correction required is unequal in different meridians of the eye. So, they will need a spectacle lens with a cylinder power correction in addition to the spherical power correction.
What the Numbers on Your Spectacle Prescription Indicate
Visual defects occur in those working on digital screens mostly and can be corrected by using lenses with proper power prescribed by an ophthalmologist.
