refractivity

noun 0.738

optical power

noun 0.711

refractive index

noun 0.689

refractor

noun 0.621

refraction

noun 0.611

resolving power

noun 0.607

dioptric

noun 0.597

refractometry

noun 0.587

refractometer

noun 0.575

diopter

noun 0.563

refracting telescope

noun 0.560

reflectivity

noun 0.549

power factor

noun 0.528

specific power

noun 0.519

refractory

noun 0.513

birefringence

noun 0.506

photoreflectance

noun 0.505

retinoscopy

noun 0.503

dioptrics

noun 0.502