While there are no completely accepted definitions of blindness, vision loss, or vision impairment, here are some definitions to help 
differentiate between visual terms. According to the Encyclopedia of Public Health, total blindness is the "inability to tell light from dark, or the total inability to see," while visual impairment or vision loss is "a severe reduction in vision that cannot be corrected with standard glasses, contact lenses, medicine, or surgery, and reduces a person's ability to function at certain or all tasks." Individuals can be blind or visually impaired from birth or develop blindness or vision impairment from accidents, illness, or natural causes.
Statistics from "Prevalence Estimates - Vision Loss and Blindness (CDC)"
