A property of a material that changes the speed of light, computed as the ratio of the speed of light in a vacuum to the speed of light through the material. When light travels at an angle between two ...

A refraction test is usually given as part of a routine eye examination. It may also be called a vision test. This test tells your eye doctor exactly what prescription you need in your glasses or ...

Recent experiments that demonstrate the negative refraction of light could bring a heated scientific debate to a close, and give negative-index materials a positive future Figure 1: Negative-index ...

Researchers used ultrasonography, phakometry, keratometry, pachymetry, interferometry, anterior segment optical coherence tomography and high-resolution MRI on the right eyes of 91 adults, according ...

Researchers at Harvard’s John A. Paulson School of Engineering and Applied Sciences have announced the first on-chip metamaterial with a refractive index of zero — meaning the phase of light can ...

I try not to write about optics too often because, well, I love optics, but no one else does. Unfortunately for you, I can’t resist the subject. If you turn over your cell phone, you will find the ...