| Metamaterial research is an emerging field that uses manmade substances to alter the way materials refract light or electromagnetic radiation. |
| Ideally we would like to refract the shadow ray too, but mathematically this is a much more difficult problem to solve. |
| They reflect and refract the light, giving the depth and luminosity of a precious gem. |
| The regional variation of ocean depth acts as a lens to refract the waves, just as a lens refracts light. |
| They cut glass, they refract light into perfect hearts-and-arrows, and they have superlative fire and brilliance. |
| Visibility is affected by the plankton levels and thermoclines that refract the light so that an otherwise perfect image can get a woolly edge. |
