Most people understand that UV rays cause skin damage, and that UV rays can also harm the eyes. If the eye is protected against UV rays, it will cause health problems such as cataracts, skin cancer near the eyes and pterygium, an abnormal growth of the cornea. The research staff at Penn State University hopes to have a new formula made of glass for sunglasses to better protect the eyes. The research team found that the addition of barium oxide to the phosphate glass may make sunglasses, windows and solar cells more effective in blocking UV rays and increasing radiation resistance.
Traditional sunglasses are made of silicate glass. In the past, yttrium has been added to silicate glass to improve its UV absorption characteristics, but silicate glass can only absorb a portion of helium. If it is absorbed excessively, it will turn yellow. This is not an optimal result for sunglasses and windows. However, researchers found that phosphate glass absorbs more germanium than silicate glass, before the glass changes color.
JenRygel, one of the researchers of the research project and Carlo Pantano, a professor of materials science and engineering, and director of the Institute of Materials at the University of Pennsylvania, compared the 11 synthetic glasses with different concentrations of germanium, aluminum, phosphorus, and silicon. They found that phosphate glass absorbs 16 times more helium than silicate glass and maintains the ability of phosphate glass to absorb UV light and maintain normal color.
“We can add more helium to the phosphate glass without destroying the glass properties. Moreover, these glasses still look good,†Rygel said. The germanium element is in two forms, CeIV and CeIII present in the glass. Phosphate glass can wash more helium without changing the color, and the main reason is that it absorbs more than two thorium elements. It seems that in the phosphate glass species, germanium elements do not absorb blue light.
"A good example is like a solar cell. Solar cells do not use ultraviolet rays. In fact, ultraviolet radiation will cause damage to solar cells. If you add germanium to glass, it will be more effective in blocking the intake of ultraviolet rays. Extend battery life.†Studies have shown that the addition of niobium will not only hinder the obstructive effect of ultraviolet rays, but also increase the ability to resist radiation gamma rays and X-ray damage. This kind of cerium-added phosphate glass will be used in the field of sunglasses, windows and solar cells in the near future.