You may not wish to promote certain sunglass brands. But I am confused about how to find a cheaper pair that still can guarantee the 99 percent to 100 percent UV protection. Many are made in China and say 100 percent UV protection. But how do I really know? An answer to this could help many people who cannot afford higher prices.

Typically, most sunwear lenses will be UV absorptive to some degree. If lenses are marked CR-39R plastic, about 88 percent of UV light is absorbed. If sunglasses contain polycarbonate lenses, UV absorption will be 100 percent. All better quality non-prescription polarized sunglasses sold through optical stores are 100 percent UV absorbing. For the very inexpensive polarized sunglass — thin, bent sheet polarized types provide UV absorption. Lenses that are polycarbonate are usually UV absorptive. However, many cheap sunglasses use a material called triacetate. This material absorbs only about 40 percent of the UV rays. Lenses may also be made of other acrylic materials, which will vary from partially to fully absorbent.

For those computer wokers,redioactive is the biggest enermy that damage their eyes,so choose a low redoactive computer screen is very important to protect your eyes. When speak of displays ,people will be apt to LCDs ,but not CRTs ,we can not deny that LCDs can provide a much more clear sight to the viewers ,but it indeed do more harms to your eyes,why ?Because LCDs have a fixed pixel size.When using LCDs you can not adjust the resolution to be bigger and smaller like CRTs.If you use a CRT,be sure your screen is set to the highest refresh rate-it will provide you a much more comfortable vision.