Liwiro lomwe kutsogolo kwa mafunde a ndege ya monochromatic kumafalikira motsatira njira yake yodziwika bwino kumatchedwa gawo liwiro la mafunde. Liwiro lomwe mphamvu yamafunde amayendera imatchedwa ray velocity. Kumene kuwala kumayenda monga momwe diso la munthu limaonera ndi kumene kuwalako kumayenda.

Kwa kristalo yopanda maginito imodzi, kuthamanga kwa gawo la mafunde a planar ndi perpendicular komwe kumadutsa magetsi. D ndi mphamvu ya maginito H, pamene mphamvu kufalitsa malangizo a mafunde kuwala ndi perpendicular H ndi mphamvu yamagetsi yamagetsi E. Dielectric constant ya anisotropic optical media ndi yachiwiri-order tensor.D ndi E Nthawi zambiri sizimayenderana, motero liwiro la gawolo v ndi liwiro la mzere v_r nthawi zambiri sizigwirizana. Zomwe zikuphatikizidwa ndi Angle α pakati pawo amatchedwa wamba angle, yomwe ndi ntchito ya mayendedwe a liwiro la gawo (kapena liwiro la ray) ndi mayendedwe a D (kapena E) (monga momwe zasonyezedwera pachithunzichi). Kuthamanga kwa gawo ndi liwiro la mzere nthawi zambiri sizofanana, ndipo mgwirizano pakati pawo ndiv=v_rcosα.

Chiŵerengero cha liwiro limene kuwala kumayenda popanda kanthu (c) mpaka liwiro lake v m'njira yoperekedwa mu anisotropic optical medium imatchedwa refractive index ya komweko. Mofananamo, chiŵerengero chac kwa liwiro la cheza mu njira inayake n_r=c/v_r imatchedwa refractive index ya ray kumbali imeneyo.

WISOPTIC mafunde-mbale