Introduction

Have you ever been sunburned? If so, you are familiar with the fact that ultraviolet (UV) light can damage your skin. But UV light can damage your eyes as well. UV light is absorbed by your eye and can cause a burn just like a sunburn on your skin. This condition, sometimes called snowblindness or welders flash, usually only lasts a few days. But UV light can also cause cataracts – cloudy spots on the lens of your eye that could require surgery or lead to blindness. So how do you protect your eyes? Do sunglasses do a good job of blocking UV radiation? Are expensive sunglasses better than cheap sunglasses? Are sunglasses better than regular eye glasses? These are some of the questions you will investigate in this experiment.

The ultraviolet band is broken into three types referred to as UVA, UVB, and UVC. The most harmful of these three, UVC light, is absorbed by the atmosphere and does not reach the Earth’s surface. UVA light is deep-penetrating and causes tanning, wrinkles, and some forms of skin cancer. UVB light is also responsible for many skin problems such as sunburns and several forms of skin cancer.

In this experiment, you will measure the UVB-blocking performance of various types of sunglasses and eyeglasses.

Objectives

In this experiment, you will

  • Use a UVB Sensor to measure UVB light.
  • Determine the percent UVB light that is blocked by various kinds of sunglasses and regular eyeglasses.