Many people may discover they have a cataract when they make new glasses and still cannot see well, especially if they are over the age of 50. Cataracts usually cause a gradual, progressive, painless, blurring of vision in one or both eyes. Some patients also complain of increasing glare in bright light or difficulty seeing while driving at night. Certain types of cataracts also cause progressive myopia (increased short-sightedness) with frequent changes of spectacle power. If you are noticing any such signs, you can see a cataract eye specialist for proper diagnosis.