Refractive errors occur when the shape of the eye prevents light from focusing directly on the retina.Regular eye exams by an optometrist or ophthalmologist are crucial for accurate diagnosis and appropriate correction of refractive errors.Presbyopia:
Type of Refractive Error: Difficulty focusing on close objects, typically affecting individuals over 40.Causes: Irregular shape of the cornea or lens, resulting in light focusing on multiple points on the retina.The main types of refractive errors include myopia, hyperopia, astigmatism, and presbyopia.Here are the details for each:

Myopia (Nearsightedness):
Type of Refractive Error: Difficulty seeing distant objects clearly.Degree of Refractive Error: Measured in diopters, and may have both cylindrical and spherical components.Keratoconus:
Type of Refractive Error: Progressive thinning and bulging of the cornea.Hyperopia (Farsightedness):
Type of Refractive Error: Difficulty seeing close objects clearly.Causes: Imbalance in the eye muscles or neurological issues affecting eye movement control.Degree of Refractive Error: Can result in varying degrees of myopia, astigmatism, and irregular astigmatism.Causes: Genetic factors, eye rubbing, and certain systemic diseases may contribute.