Ob chav refraction yog ib qho khoom siv kho qhov muag ntawm cov khoom siv uas muaj qhov ntsuas qhov cuam tshuam uas nyob ntawm qhov polarization thiab kev taw qhia ntawm kev nthuav tawm ntawm lub teeb. Birefringence feem ntau yog suav tias yog qhov sib txawv siab tshaj plaws ntawm cov ntsuas refractive uas pom los ntawm cov khoom siv. Crystals uas tsis yog - cubic crystal lug feem ntau yog birefringent, zoo li cov yas nyob rau hauv txhua yam kev nyuaj siab.
