N()=∑e=∑e k[L+(n-D)dine ∑ ik(n-ldsine n=1 n n=1 e ∑ i2(n-1)B ikL inb n=0 2INB iNB-Nβ-e INB 2iB B iB (N-1)B Sin( NB) i(N-1)B N() sn B MO)Si(Nβ)N元干涉因子 sin B
= = N n ikLn N e 1 ( ) ~ = + − = N n i k L n d e 1 [ ( 1) sin ] 1 = − = N n ikL i k n d e e 1 1 ( 1) sin = − = N n ikL i n e e 1 2( 1) 1 i i iN iN i iN e e e e e e − − = − − i iN e e 2 2 1 1 − − = − = = 1 0 1 2 N n ikL i n e e ( ) ( 1) e N i N− = sin sin( ) ( 1) N e i N− = sin sin( ) ( ) N N = N元干涉因子
U(P)=U()N() KU(Q-e(N-1B sn u sin NB u sin B sin、2, sin NB I(P)=lo u sIn KU(O C 满足近轴条件时,单个狭缝在像方 f 焦点处的光强
( ) ~ ( ) ~ ( ) ~ U P =U N sin sin sin ( ) ~ ( 1) 0 N u u e f e KU Q i N ikr − = 2 2 0 ) sin sin ) ( sin ( ) ( N u u I P = I 2 0 ( ) ~ 0 f KU Q I a = 满足近轴条件时，单个狭缝在像方 焦点处的光强
(inu/u)2单元衍射的数值扩大6倍 (sinNβ/sinβ) U=Tm asine/M WWWW WA ∧ N WV β= tt sine/A d=4a N-5 (sinu/)(siNβ/sinB)2 β= It dsin6 单元衍射与N元干涉曲线周期之比为d/a
单元衍射与N元干涉曲线周期之比为d/a
I(sinu/u) (sinN B/sin B)2 N=4 d=3a u=J asin 0/n
N=4 d=3a (sinNβ/sinβ)2 I0(sinu/u)2 u=πasinθ/λ
N=6,d=5a JL∧
N=6,d=5a