The refractive index of diamond causes light to bend sharply and sparkle.

The refractive indices of the composite materials were measured at multiple wavelengths to determine their dispersion.

When light passes through a calcite crystal, double refraction produces two images of the object viewed through it.

Astronomical refraction caused the star's apparent position to shift slightly above the horizon.

Astronomers must correct for atmospheric refraction when measuring the precise positions of stars, because the Earth's atmosphere bends starlight and makes celestial objects appear higher than they truly are.

Astronomic refraction causes stars to appear slightly higher above the horizon than their true positions.

The optometrist compared the refractive powers of the two lenses before recommending one to the patient.

The optometrist explained that the lens's refractive power determines how sharply images are focused on the retina.