What does singly refractive (isotropic) mean?

What does singly refractive (isotropic) mean?

• A. Isotropic
• B. Singly Refractive (Isotropic)
• C. Anisotropic
• D. Birefringent

Answer: (B)

Isotropy means the optical properties are the same in every direction. When a material is isotropic, light has a single refractive index and does not split into two rays at a boundary, so it is singly refractive. This is exactly what the paired term describes, making it the best match. In contrast, anisotropic materials have direction-dependent indices and can cause birefringence (double refraction), which is the opposite behavior.

Isotropy means the optical properties are the same in every direction. When a material is isotropic, light has a single refractive index and does not split into two rays at a boundary, so it is singly refractive. This is exactly what the paired term describes, making it the best match. In contrast, anisotropic materials have direction-dependent indices and can cause birefringence (double refraction), which is the opposite behavior.