[分享]Arizona眼睛模型 [复制链接]

简介 rb"J{^  
,".1![b  
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。 3`%]3qd}  
4=BIYC"Lu  
模型 PV[Bqt  
fVb~j;  
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。 _6y#?8RMB  
8dgi"/[3  
0Nvk|uI V[  
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. Ol%KXq[  
uq.!{3)8  
光源 K{]9Yo  
! MTmG/^  
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。 [&Yrnkgr  
Y@jO#6R  
~Ox !7Lp  
.paKV"LJ  
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。 n(#|  
3FD6.X>x  
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。 r |H 1Yy  
<$"  
-a=RCzX]  
w
Fe
?0u  
视网膜的散射 8@$`'h^6  
z CS.P.$  
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。 #N?VbDK9_  
E.Vlz^B  
jpGZ&L7i&  
*n"{]tj^>  
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。 -nHt6AbqP  
>8v4fk IK  
yH9(ru  
3xhGmD\SKO  
脚本 jTeHI|b  
O`M6=\  
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： rEoMj)~\4&  
/
/ k`X  
5YZh e4R  
l;~b:[r  
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。 xWiR7~E  
余下的脚本计算与屈光度有关的所有参数。 NFsCq_f  
L?Fb}  
分析 eBZ94rA]  
io[>`@=  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 !l(O$T9T  
_HAtTW  
-eQ>3x&3r  
脚本代码 ^uV=|1<%  
}wIF$v?M  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. hy]8t1894  
"hbCP4  
Dim entity As T_ENTITY X21k7 Ls  
Dim op As T_OPERATION "9^OT  
Dim mat As T_MODELMATERIAL ~L
fFLC  
Dim A As Double G`oY(2U  
Dim pupilDiam As Double ZL7#44  
Dim eID As Long +$;#bw)yH  
Dim parID As Long Q2)CbHSz  
Dim count As Integer 6)h~9iK  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double qlNB\~HCe  
Dim tlens As Double, nlens As Double 

>7$h  
Dim curv As Double, conic As Double "n, %Hh  
Dim ok As Long W6A-/;S\
 
1_B;r9x  
Sub Main _kZ&t_]  
a !yBEpMo  
    '用户输入对话框 EJid@  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 !^x;4@Ejm  
        TextBox 220,21,40,21,.TextBox1 'default: 0 1)BIh~1{p  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 INRP@Cp1  
        OKButton 40,91,90,21 J?$`Tnx^  
        CancelButton 190,91,90,21 J5zKwt  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 ev[!:*6P  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ml1My1  
    End Dialog B;A< pNT  
    Dim dlg As UserDialog u$Wv*;TT%  
dsG:DS`q  
    ok = Dialog (dlg) +Y_]<  
uE ^uP@d  
    If ok=0 Then    'cancel button was pressed *v:o`{vM[  
        Print "Execution cancelled." f{w[H S,z  
        End @#>YU
  
    End If peZ'sZ6  
*JA0Vs5  
    'Assign accommodation and pupil diameter & use defaults if field left empty G@4n]c_  
    If dlg.TextBox1 = "" Then )~{8C:  
        A = 0           'Default accommodation 
er0y~  
    Else vWZ?*0^  
        A = CDbl(dlg.TextBox1) (v0i]1ly[  
    End If y;VmA#k`  
w?JM;'<AYQ  
    If dlg.TextBox2 = "" Then y6P-:f/&*  
        pupilDiam = 4   'Default pupil diameter WxJV zHtR  
    Else U}<'[o V  
        pupilDiam = CDbl(dlg.TextBox2) [l*;+N+  
    End If (r-8*)Qh8  
vVFT0_  
    Print " " IWT -)+  
    Print "Accommodation = " & A & " Diopters" D}/nE>*  
    Print "Pupil Diameter = " & pupilDiam & " mm" n%d7`?tm4  
S^7u`-  
    ' Calculate new parameters with accommodation THcX.%ToT  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 1UN$eb7  
>f:OU,"  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens .F]"%RK[  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens qpX`ZY^  
l}XnCOIT,  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens eEX*\1Gg  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens IQyw>_~]  
;0nL1R]w(  
    tlens = 3.767 + 0.04*A                  'Lens thickness o(@^V!}V  
=p \eh?^  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction t $u.  
`##^@N<P  
    'Adjust parameters to account for accommodation uX8G<7O^  
)E}eK-Yu  
    '************************************************************************* ,h},jkY4  
    'Aqueous thickness (Position of Lens) roNs~]6  
    '************************************************************************* @ 5V3I^  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) wF)g@cw  
    GetCustomElement eID, entity 7xfN}iHG  
?Vc/mO2X  
    parID = FindFullName( "Geometry.Arizona Eye" ) J8@7 5p9  
 Wo,fHY  
    ' Delete any shift(s) in z
-f=4\3y3p  
    count = 0 6G;t:[H G  
    While GetOperationCount(eID)>count 4=ZN4=(_[  
        GetOperation eID, count, op N3&n"w _d  
        If op.Type="ShiftZ" Then Z#flu Q%V  
            DeleteOperation eID,count 8RJa;JsH  
            count=count-1 _MzdbUb5,  
        End If wQrD(Dv(yA  
        count=count+1 f=Kt[|%'e  
    Wend 43/!pW  
DX<xkS[P  
    'Set new shift in vve[.Lud'  
    op.Type = "ShiftZ" 1zIrU6H2;_  
    op.val1 = taq ke5_lr(  
    op.parent = parID vf h*`G$  
    AddOperation eID, op Z]k+dJ[-  
    Print "Set aqueous humor thickness = " & taq-0.55 Dlx-mm_  
 r95$( N  
    '************************************************************************* 3NlG,e'T2  
    'Radius and conic constant of anterior lens G~19Vv*;  
    '************************************************************************* y9-}LET3j  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ~.<}/GP]_  
    GetConic eID, entity, curv, conic b)+;@wa~  
l1D"*J 2`  
    SetConic eID, entity, 1/Rant, CCant {>zQW{!  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 3R[,,WAj$  
Ku;8Mx{  
    '************************************************************************* y*5$B.u`.  
    'Radius and conic constant of posterior lens ka[%p,H  
    '************************************************************************* ZN-5W|' O  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) y3NMt6  
    GetConic eID, entity, curv, conic hG>3y\!#  
%^<A`Q_  
    SetConic eID, entity, 1/Rpost, CCpost uz@WW!+o  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost GFO(O  
U?yKwH^{  
    '************************************************************************* "(^1Dm$(  
    'Lens thickness (Position of posterior lens surface) =f-.aq(G/  
    '************************************************************************* mx")cGGQ  
KI8Q =*  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) uJ>_ 2  
f*GdHUZ*  
    ' Delete any z-shift(s) q@&.)sLPgO  
    count = 0 ,?>:Cdz4  
    While GetOperationCount(eID)>count *Q:EICDE7  
        GetOperation eID, count, op GeCyq%dN  
        If op.Type="ShiftZ" Then A]mXV4RmI  
            DeleteOperation eID,count 2a[_^v $v  
            count=count-1 p/%B>Y>  
        End If pk:2>sx/  
        count=count+1 o_DZ  
    Wend xN]88L}Tn  
zFGZ;?i  
    'Set new z-shift 6$"0!fl>  
    op.Type = "ShiftZ" 09C[B+>h  
    op.val1 = tlens ]Qb85;0)  
    op.parent = parID yct^AN|%  
    AddOperation eID, op .~fAcc{Qj  
    Print "Set lens thickness = " & tlens @(Y+W2Iyy+  
kpt0spp  
    '************************************************************************* SSG}'W!z  
    'Lens index of refraction c=A)_ZFg  
    '************************************************************************* VLfE3i4Vwl  
    eID = FindMaterial( "Lens" ) 6=xbi{m$  
    GetModelMaterial eID, mat }Qo:;&"3  
iv]*
HE  
    mat.Nd = nlens *Mr?}_,X*  
    SetModelMaterial eID, mat ,6FmU$ Kn  
    Print "Set lens index of refraction = " & nlens 8I*
WVa$l  
??.9`3CYo  
    '************************************************************************* Ib665H7w  
    'Pupil diameter `VxfAV?}  
    '************************************************************************* h(VF  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) FtL{f=  
%T:7I[f  
    'Adjust pupil diameter (trimming volume inner hole) |6}:n,KA.  
$Q!J.}P@  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" fooQqWC)  
zIjUfgO/M  
    ' Adjust pupil location to just in front of the lens 235wl  
    parID = FindFullName( "Geometry.Arizona Eye" ) V`MV_zA2  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) #aV2+`d  
    count = 0 a;$'A[hq  
    While GetOperationCount(eID)>count MGzuQrl{H  
        GetOperation eID, count, op [$b\#{shtP  
        If op.Type="ShiftZ" Then y8.(filNB  
            DeleteOperation eID,count BXf.^s{H  
            count=count-1 >9v?p=  
        End If (ON_(MN   
        count=count+1 ,wvzY7%  
    Wend LVj62&,-  
    op.Type = "ShiftZ" jS,zdJs=  
    op.val1 = taq-0.01 .g6DKjy>  
    op.parent = parID kTLA["<m  
    AddOperation eID, op 6s"Erq5q  
'F665  
    Print "Set pupil diameter = " & pupilDiam ADa'(#+6  
O]Mz1 ev|  
    'Update AZ Eye subassembly Description 5c~OG6COx  
    eID = FindFullName( "Geometry.Arizona Eye" ) v9[[T6t/'  
    GetEntity eID, entity bl)iji`]  
    entity.Description = "Accommodation = " & A & "D" !MiH^wP  
    SetEntity eID, entity K&WNtk3hT  
J0hY~B~X  
    Update H8}}R~ZO  
    Print "DONE!" ,^_aqH  
     )!!xvyc  
End Sub
z!={d1u#T  
*
qLOr6  
如果屈光度是4，光瞳直径是4，则会输出如下数据： %7$oig\wE  
'e(`
2  
Accommodation = 4 Diopters Tmo+I4qoL  
Pupil Diameter = 4 mm mne=9/sE"  
Set aqueous humor thickness = 2.81 2_4m}T3  
Set anterior lens radius = 10.4 and conic constant = -2.375869 cQaEh1n  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 DfCo=  
Set lens thickness = 3.927 sH>Z{xjr  
Set lens index of refraction = 1.42672 H...!c1M@  
Set pupil diameter = 4 +=y ktf  
DONE! T&2aNkuG  
Wkk=x&  
U 6y ;V  
QQ：2987619807 B(GcPDj(K