Macular Degeneration/ Age-related Macular Degeneration (AMD)
AMD is a degenerative condition of the macula, which is the part of the retina responsible for the sharp, central vision needed to read or drive. Because AMD affects the macula, central vision loss may occur.

Colour Blindness
Colour blindness is not a form of blindness at all, but a deficiency in the way you see colour. With this vision problem, you have difficulty distinguishing certain colours, such as red and green or blue and yellow. Red-green colour deficiency is the most common form of colour blindness; a less common form is blue-yellow colour deficiency.

Cataracts and Cataract Surgery
A cataract is a clouding of the eye's natural lens, which lies behind the iris and the pupil. The lens is mostly made of water and protein. The protein is arranged in a precise way that keeps the lens clear and lets light pass through it. But as we age, some of the protein may clump together and start to cloud a small area of the lens. This is a cataract, and over time, it may grow larger and cloud more of the lens, making it harder to see.

Amblyopia (Lazy Eye)
Amblyopia, also known as lazy eye, is a vision problem that affects just two to three percent of the population, but if left uncorrected, it can have a very big impact on their lives. Central vision does not develop properly, usually in one eye, which is called amblyopic. A related condition, strabismus, sometimes causes Amblyopia.

Conjunctivitis (Pink Eye)
The conjunctiva is the thin, clear membrane over the white part of the eye; it also lines the eyelids. Inflammation of this membrane is called conjunctivitis. Its common name, pink eye, can refer to all forms of conjunctivitis, or just to its contagious forms.

Glaucoma
Your eye has pressure just like your blood, and when this intra ocular pressure (IOP) increases to dangerous levels, it damages the optic nerve. This can result in decreased peripheral vision and, eventually, blindness. Glaucoma is similar to ocular hypertension but with accompanying optic nerve damage and vision loss.

Ptosis
Ptosis refers to the drooping of an eyelid, and affects only the upper eyelid of one or both eyes. The droop may be barely noticeable, or the lid can descend over the entire pupil. Ptosis can occur in both children and adults, but happens most often due to aging.

Styes
A stye (also spelled "sty") develops when a gland at the edge of the eyelid becomes infected. Resembling a pimple on the eyelid, a stye can grow on the inside or outside of the lid. Styes are not harmful to vision, and they can occur at any age.

Retinal Detachment
A retinal detachment is a serious and sight-threatening event, occurring when the retina becomes separated from its underlying supportive tissue. The retina cannot function when these layers are detached, and unless it is reattached soon, permanent vision loss may result.

Source: http://www.allaboutvision.com/