各位光学专业的大神，我最近在用ASAP对微阶梯反射镜（如附图）进行模拟。一束单色平行光垂直入射到微阶梯反射镜上，用探测器接收反射光。如图，理论上在探测器上应该也是均匀的光场，但是用ＡＳＡＰ的高斯光束分解模拟得到的结果却如图所示。这是为什么呢？ 7W'&v+\
以下是我的ＡＳＡＰ代码，可以拷贝运行一下。 (%c&Km7K
P{L S +.
SYSTEM NEW /X]gm\x7s
RESET ppo.# p0w
8J#x B
UNITS MM QQ`tSYgex
WAVELENGTHS 3.7 UM L +mE&
97[wz C,
COATING PROPERTIES 4.Q [Tu
1 0 'REFLECT' 1N_T/I8_F
0 0 'ABSORB' ^7uXpqQBr
w&@zJ [
PARABASAL 4 8BrC@L2E0
BEAMS COHERENT DIFFRACT 3@nIoN'z
WIDTHS 1.6 MDQ:6Ri
&xt[w>/ i
A=1 e"UXG\8D
N=32 Q ;N)$Xx
L=(N)*(A) r$v \ \^?2
D1=0.625E-3 >k
==7#P
D2=(N)*(D1) G1-r$7\
!! 微阶梯镜======================= [p' A?-
$DO -16 15 1 ,A &`W E
{SURFACE JMk2OK {0
PLANE Z 0 RECTANGLE (A)/2 (L)/2 C A1Jjm=
OBJECT 'MIRROR2_?' _Ss}dU9
INTERFACE COATING REFLECT AIR AIR cuC'
o\f
SHIFT X (A)*?+(A)/2 ])G| U A.
SHIFT Z (D2)*? *<:6A&'D9
} q %j8Js
GROUP MIRROR2_? H s$HeAp;
SHIFT Z (L) |)v}\-\ #
ROTATE X -90 0 0 }.(DQwC}1k
!! DETECTOR====================== {sxdDl
SURFACE 6ddRFpe
PLANE Y -(2*L) RECTANGLE (L)/2 (L)/2 P l!E$
OBJECT 'DETECTOR' amq,^
INTERFACE COATING ABSORB AIR AIR f[vm ]1#
!! SOURCE ======================= l-cBN^^
GRID RECT Y -(L) -(L)/2 (L)/2 -(L)/2 (L)/2 (256) (256) }9^'etD
SOURCE DIR 0 1 0 ML lvs a0
!! !!TRACE PLOT========================= e$teh`
p3
!!WINDOW Y Z p0y|pD
!!PLOT FACETS 5 5 !!OVERLAY
!4`:(G59
TRACE!! PLOT T{2)d]Y
!!$VIEW nGwon8&]]
:{^~&jgL
CONSIDER ONLY DETECTOR !!CONSIDER ONLY DUMY g_n_Qlo
WINDOW X -(L)/2 (L)/2 Z -(L)/2 (L)/2 tK@7t0
PIXELS (256) RT3(u twO
SPREAD NORMAL (&87 zk
DISPLAY |Xm$O1Wa
!! FORM 0.5 ;&gk)w6*
PICTURE dl3;A_ 2
RETURN
