Light sensitivity also know as photophobia, is an intolerance of light, some can feel discomfort from bright lights, and some extreme cases can not stand any type of light. People could be squint when appear strong light. And light sensitivity is a symptom, not a disease, it can be caused by many different reasons.
If someones meets the light and find the natural change of pupils from big to small, he may have the light sensitivity. The more serious one is that your eyes will feel burning when you see the light. They should better wear the sunglasses when they are out in the strong sun lights. They could also do the warm compress often which will make their eyes get comfortable.
The light sensitivity is an eye disease what caused by ultraviolet radiation. It is mainly because corneal epithelium burn from ultraviolet radiation. This symptom always found in those person who always work under the irradiation of strong light. If you eyes get light sensitivity, go to pharmacy buy some eye drop and try not to go out to see strong light within two weeks. If you have to go out, remember wearing sunglasses.