[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 H(9%SP@[c  
人眼光学模型可用来设计眼科用设备，光学系统注定了要与人眼一起使用。本文演示了这样一个模型：Arizona眼睛模型，在Jim Schwiegerling教授的书中有详细描述：《Field Guide to Visual and Ophthalmic Optics》。AZ眼睛模型达到了基于平均临床数据所决定的轴上和轴外像差等级。FRED文件包含了此眼睛模型及几个用来分析它的光源，并包括一个基于想要的屈光度来调整模型的内嵌脚本。 Gh}sk-Xk=  
TbbtD"b?  
模型 e2CjZ"C  
F+ qRC_C>O  
模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 #8iRWm0*6  
"_t2R &A  
u^T)4~(  
在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. '1{co/Y  
xU+
c?OLi  
光源 4%>iIPXi.(  
(4=NKtA^G  
多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 ua[ d  
p'z fo!  
Lpd q^X  
$\?BAkx  
除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 3*C9;Q}  
c+$alwL~  
在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 ?CIMez(h  
h}r64<Y2{  
a<-NB9o~v  
w&<-pIa`  
视网膜的散射 MebLY $&8  
#AHX{<  
在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 #vCtH2  
veX#K#  
tmEF7e`(o  
L5$r<t<  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 TpXbJ]o9  
uj#bK 7  
:k9n 9  
[yj-4v%u`  
脚本 VBV y3fnj  
.:gZ*ks~  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： 6$]@}O^V  
n
v>|,&;  
f
ui;F"+1  
^1y (N>W  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 w5zrEk#  
余下的脚本计算与屈光度有关的所有参数。 d$
.t0-lC  
:uwB)G  
分析 }4G/x;D  
#mu3`,9V  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 :f<:>"<  
RMJq9a  
o"h*@.  
脚本代码 :: IAXGH)  
_Q&O#
f  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. cb|cYCo5  
*$+k-BV
  
Dim entity As T_ENTITY UC&f  
Dim op As T_OPERATION  %T9'dcM  
Dim mat As T_MODELMATERIAL IJX75hE0g  
Dim A As Double G-FeDP
  
Dim pupilDiam As Double MP"Pqt  
Dim eID As Long {[B^~Y>Lr  
Dim parID As Long ?+6w8j%\  
Dim count As Integer c*F'x-TH  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double |ci1P[y  
Dim tlens As Double, nlens As Double #a7 Wx}  
Dim curv As Double, conic As Double ,c3gW
2E  
Dim ok As Long /;P* ?  
EPO*{bN7O  
Sub Main }t.J;(ff:  
gZkjh{rQ  
    '用户输入对话框 _g{*;?mS  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 
QN!.~>  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Th"0Cc)  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 yxv]G6  
        OKButton 40,91,90,21 kC :pa
l  
        CancelButton 190,91,90,21 4q%hn3\  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 2AN6(k4o  
        TextBox 220,49,40,21,.TextBox2 'default: 4 kFCjko  
    End Dialog @log=^  
    Dim dlg As UserDialog #fT1\1[]  
8&d
s  
    ok = Dialog (dlg) B^8]quOH  
-TL `nGF  
    If ok=0 Then    'cancel button was pressed NR98I7  
        Print "Execution cancelled." UC@&! kM  
        End T
F0DQP  
    End If LHy-y%?i  
2VSs#z!  
    'Assign accommodation and pupil diameter & use defaults if field left empty PH,MZ"Z%  
    If dlg.TextBox1 = "" Then /%O+]#$`0  
        A = 0           'Default accommodation \TchRSe  
    Else F|Y}X|x8Q  
        A = CDbl(dlg.TextBox1) u+ wKs`  
    End If D)0pm?*5A  
:i{$p00 G  
    If dlg.TextBox2 = "" Then |q0MM^%"  
        pupilDiam = 4   'Default pupil diameter Ojea~Y]Sr  
    Else }Z^r<-N  
        pupilDiam = CDbl(dlg.TextBox2) M mihWD02  
    End If P1\:hh  
*^h$%<QI  
    Print " " W.nQYH  
    Print "Accommodation = " & A & " Diopters" Z.!tp  
    Print "Pupil Diameter = " & pupilDiam & " mm" %+>t @F,GM  
6LVJ*sjSy  
    ' Calculate new parameters with accommodation <OYy;s  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness WnATgY t  
IdY\_@$ v  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens B Q)1)8r  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens :#yjg1aej  
y[L7=Td  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens _dg2i|yP<  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 7&I+mw/X  
(YOp  
    tlens = 3.767 + 0.04*A                  'Lens thickness jg,oGtRz  
,7wxVR%Ys  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction J~\`8cds  
d-cK`pSB  
    'Adjust parameters to account for accommodation ,F4_ps?(  
OfSy_#aEK  
    '************************************************************************* x37pj)i/  
    'Aqueous thickness (Position of Lens) /Ah|P
o  
    '************************************************************************* d{~5tv- H  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) @(;zU~l/  
    GetCustomElement eID, entity 'yrU_k,h  
Dg:2*m_!j{  
    parID = FindFullName( "Geometry.Arizona Eye" ) ;p$KM-?2D  
#gHs!b-g@  
    ' Delete any shift(s) in z  xr }jw  
    count = 0 Jl,mYFEZ  
    While GetOperationCount(eID)>count !'yl
h8}  
        GetOperation eID, count, op hM":?Rx  
        If op.Type="ShiftZ" Then #fF~6wopV  
            DeleteOperation eID,count ^5"2s:vP  
            count=count-1 Y<A593  
        End If ^CZ)!3qd1  
        count=count+1 l7g< $3
 
    Wend :tc]@0+  
f]P&>j|  
    'Set new shift in xj1FCT2  
    op.Type = "ShiftZ" AqD)2O{VO  
    op.val1 = taq RsY7F;  
    op.parent = parID |'C{nTX  
    AddOperation eID, op Pf?*bI  
    Print "Set aqueous humor thickness = " & taq-0.55 %J_`-\)"{~  
'dnTu@mUT  
    '************************************************************************* (l|:$%[0  
    'Radius and conic constant of anterior lens ("UzMr,  
    '************************************************************************* T'n~QfU  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) xB%Felz  
    GetConic eID, entity, curv, conic n+C,v.X  
JZCRu_M>|  
    SetConic eID, entity, 1/Rant, CCant sQBl9E'!be  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant k"J[mT$b  
p6qza @  
    '************************************************************************* hQm"K~SW
=  
    'Radius and conic constant of posterior lens aNqhxvwf  
    '************************************************************************* >bKN$,Qen  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) }~Am{Er<l  
    GetConic eID, entity, curv, conic U[!x 0M  
D@M ZTb  
    SetConic eID, entity, 1/Rpost, CCpost JWu^7}@~=  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost [Rqv49n*V  
3#d5.Ut  
    '************************************************************************* z}Qt6
na]-  
    'Lens thickness (Position of posterior lens surface) ;NyX9&@  
    '************************************************************************* {V> >a  
WVP^C71  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ^,Paih 2  
?A[q/n:K  
    ' Delete any z-shift(s) S 1%/ee3  
    count = 0 S{v [65  
    While GetOperationCount(eID)>count i.0}d5Y  
        GetOperation eID, count, op N8<Wm>GLX~  
        If op.Type="ShiftZ" Then t)yWQV  
            DeleteOperation eID,count L_>j SP  
            count=count-1 sknta0^=2  
        End If ^

|z  
        count=count+1 SA5 g~{"  
    Wend p8%/T>hK  
ZDmBuf q  
    'Set new z-shift :{iS0qJ  
    op.Type = "ShiftZ" X[ERlw1q4Q  
    op.val1 = tlens i+I%]  
    op.parent = parID `iX~cUQ  
    AddOperation eID, op c,$ >u,4  
    Print "Set lens thickness = " & tlens ~w<u!  
[SluYmW  
    '************************************************************************* KL2#Bm_  
    'Lens index of refraction .A: #l?  
    '************************************************************************* y4aW8J#  
    eID = FindMaterial( "Lens" )
!nQ!J+ g  
    GetModelMaterial eID, mat x Z3b)j2D  
cx]&ae*  
    mat.Nd = nlens &ct
y&(2p  
    SetModelMaterial eID, mat ZH9sf~7  
    Print "Set lens index of refraction = " & nlens Q4gsOxP  
hOI|#(
-  
    '************************************************************************* &ukYTDM  
    'Pupil diameter H /E.R[\+x  
    '************************************************************************* L-7?:  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) =.
@{uu;  
ogt<vng  
    'Adjust pupil diameter (trimming volume inner hole) 8pc=Oor2Tv  
!,rp|  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" xWY%-CWY.  
;\N{z6  
    ' Adjust pupil location to just in front of the lens D^(Nijl9U  
    parID = FindFullName( "Geometry.Arizona Eye" ) }L.xt88  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) B~/:["zTh&  
    count = 0 beLT4~Z=  
    While GetOperationCount(eID)>count :i
WW2fY  
        GetOperation eID, count, op dgLE/r?  
        If op.Type="ShiftZ" Then +tbG^w%  
            DeleteOperation eID,count w1Z9@*C!  
            count=count-1 qpo3b7(N  
        End If 2}Ga  
        count=count+1 aCu 8 D!  
    Wend K{eq'F5M  
    op.Type = "ShiftZ" Ga5O&`h  
    op.val1 = taq-0.01 IM
aa#8,  
    op.parent = parID <cQ)*~hN  
    AddOperation eID, op `XAlzI  
3P{ d~2  
    Print "Set pupil diameter = " & pupilDiam D4e*Wwk  
W\JbX<mQ  
    'Update AZ Eye subassembly Description LvlVZjT  
    eID = FindFullName( "Geometry.Arizona Eye" ) 9#K,@X5 j  
    GetEntity eID, entity [LDV*79Z  
    entity.Description = "Accommodation = " & A & "D" jQ &$5&o  
    SetEntity eID, entity `)sC".b7  
*v+xKy#M  
    Update AE1EZ#  
    Print "DONE!" RR,gC"cTi  
     #r\,oXTm  
End Sub Ns?8N":  
^Ht!~So  
如果屈光度是4，光瞳直径是4，则会输出如下数据： Gqe?CM  
c{YBCWA  
Accommodation = 4 Diopters ^gP pmb<x  
Pupil Diameter = 4 mm Y?cdm}:Ou  
Set aqueous humor thickness = 2.81 ~Z74e>V%  
Set anterior lens radius = 10.4 and conic constant = -2.375869 %,HuG-L  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 I[mlQmwsL.  
Set lens thickness = 3.927 p.(8ekh  
Set lens index of refraction = 1.42672 y|sU-O2}Dl  
Set pupil diameter = 4 Q\WH2CK  
DONE! 4/6?wX  
:bJT2o[