refractive index

Preposition: of

• glass: Thus this figure is not the actual physical depth of the coverslip but one modified by the refractive index of the glass itself.

Converse of object

• have: Light is guided in the core of the fiber that has a higher refractive index than the cladding by total internal reflection.

Adjective modifier

• high: Light is guided in the core of the fiber that has a higher refractive index than the cladding by total internal reflection.
• low: This is usually done by coating them in a material of lower refractive index than the fiber.