In the normal direction of the boundary: (D transmission -D incidence) = free charge density of the boundary surface.
(j transmission -J incident angle) = 0
(b transmittance -B incident angle) =0
H is used for loop integration at the boundary of two media, (rectangular loop height->; 0), and then using Stokes theorem, we can deduce that
H(H transmission -H incidence) in the tangential direction of the boundary = j of the boundary surface.
If the loop integral of E is done, because the loop integral of E is 0, it can be deduced that
E in the tangential direction (e transmission -E incidence) = 0.
If both media are ideal media (an ideal insulator with zero conductivity and no free charge)
So at this time, the free charge density of the boundary surface =0.
If written as a mathematical expression:
N-point multiplication (D2-D 1)=0 (because the free charge of pure medium is 0).
N-point multiplication (J2-J 1)=0.
N-point multiplication (B2-B 1)=0.
N-cross product (E2-E 1)=0
Cross product of n-sided interface (H2-h1) = j.
Where n is the direction vector of the boundary normal, d is the flux density, and b is the flux density.
E is the electric field strength, j is the current density, and h is the magnetic field strength.