Changes
/* Conventional Physical Optics (GO-PO) */
:<math> \mathbf{M(r)} = -Z_s \mathbf{\hat{n}\times} \mathbf{J(r)} </math>
In the case of an impedance-matched surface, Z<sub>s</sub> = η<sub>0</sub>, η<sub>s</sub> = 1, and one can write:
:<math> R_{\|} = R_{\perp} = \frac{\cos\theta - 1} {\cos\theta + 1} </math>
