E-Mail IMAGE: Researchers in the lab of Chunlei Guo, a professor of optics at the University of Rochester, have developed an optical coating that exhibits the same color in reflection (pictured) and... view more Credit: University of Rochester photo/J. Adam Fenster For more than a century, optical coatings have been used to better reflect certain wavelengths of light from lenses and other devices or, conversely, to better transmit certain wavelengths through them. For example, the coatings on tinted eyeglasses reflect, or "block out," harmful blue light and ultraviolet rays. But until now, no optical coating had ever been developed that could simultaneously reflect and transmit the same wavelength, or color.