9. 衍射场分布
∞
U ( x, y ) = ∫ ∫ U (ξ ,η )h( x − ξ , y − η )dξ dη = U (ξ ,η ) ⊗ h( x, y )
−∞
e jkz k 2
h ( x, y ) = exp[ j ( x + y 2 )]
jλ z 2z
U ( x, y ) = F −1{F {U (ξ ,η )}H ( f X , fY )}
H ( f X , fY ) = F {h( x, y )} = exp{− jπλ z ( f X2 + fY2 )}
U (ξ ,η ) = eiϕ (ξ ,η )
11. 计算模型
N
x − (n − 0.5)d
)
rectComb( x, a, d , N ) = ∑ rect (
tC b t )
n =1 a
rect ( x) = 0 [ sign(0 − x) + sign(0 + x)]
0.5[ (0.5 (0.5
U (ξ ,η ) = 2rectComb(ξ , a, d , N ) rectComb(η , a, d , N ) − 1
U ( x, y ) = F −1{F {U (ξ ,η )}H ( f X , fY )}