There are a wide variety of eye diseases prevalent across the globe, including cataract, glaucoma, and refractive errors. Most of the people have some sort of eye problems in their lifetime. As per the World Health Organization (WHO), around 2.2 billion people across the globe have a near or distance vision impairment. The leading cause of vision impairment is cataract (94 million) and uncorrected refractive errors (88.4 million). The other causes of vision impairment are glaucoma (7.7 million), corneal opacities (4.2 million), diabetic retinopathy (3.9 million), and trachoma (2 million).