[分享]Arizona眼睛模型 [复制链接]

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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。 g{dyDN$5|w  

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模型 +8v!vuO'  
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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。 ?-*_v//g  
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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. <Y9ps`{}:  
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光源 fU$zG"a_  
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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。 27gK Y Zf;  
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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。 mM>{^%2Q:  
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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。 WCU[]A  
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视网膜的散射 P|c79  
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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。 YP+0uZ[g  
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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。 TRG
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脚本 %<:?{<~wH9  
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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： if r!ha+8!  
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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。 qFt%{~a S  
余下的脚本计算与屈光度有关的所有参数。 NZmmO )p4  
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分析 3]M YHb  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 :>;-uve8'  
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脚本代码 rN8 ZQiJC  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. kfM}j
  
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Dim entity As T_ENTITY A:0  
Dim op As T_OPERATION iMYvCw/t6  
Dim mat As T_MODELMATERIAL e*:[#LJ]C  
Dim A As Double e#)}.   
Dim pupilDiam As Double ]Y}faW(&Y  
Dim eID As Long qXCl6Yo8  
Dim parID As Long /<Zy-+3  
Dim count As Integer t-3wjS1v  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 45>w=O  
Dim tlens As Double, nlens As Double R1\cAP^0  
Dim curv As Double, conic As Double >5i1M^g(  
Dim ok As Long WQ|d;[E  
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Sub Main rM/*_0[`d  
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    '用户输入对话框 u'<Y#bsR#/  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 #$e~o}(r  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Z#3wMK~  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 #sq-V,8  
        OKButton 40,91,90,21 u3dhMnUn  
        CancelButton 190,91,90,21 RHz'Dz>0  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 rbqH9 S  
        TextBox 220,49,40,21,.TextBox2 'default: 4 f8B*D4R}  
    End Dialog vFV->/u  
    Dim dlg As UserDialog 6oL-Atf  
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    ok = Dialog (dlg) vWXj6}  
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    If ok=0 Then    'cancel button was pressed hSQP '6  
        Print "Execution cancelled." b=Zg1SqV  
        End 4Q,HhqV'  
    End If plv"/KJM  
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    'Assign accommodation and pupil diameter & use defaults if field left empty I^qk`5w  
    If dlg.TextBox1 = "" Then r9yUye}  
        A = 0           'Default accommodation XfViLBY( >  
    Else 5C#&vYnq  
        A = CDbl(dlg.TextBox1) FRs5 Pb1  
    End If 5IVASqYp  

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    If dlg.TextBox2 = "" Then ,i>5\Yl%  
        pupilDiam = 4   'Default pupil diameter 4&$hBn=!  
    Else _Xsn1  
        pupilDiam = CDbl(dlg.TextBox2) sAnStS=>  
    End If M?)>, !Z)  
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    Print " " $sGX%u  
    Print "Accommodation = " & A & " Diopters" Z~T- *1V  
    Print "Pupil Diameter = " & pupilDiam & " mm" wy:.  
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    ' Calculate new parameters with accommodation /vsQ <t;~  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness &EA4`p  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens Yw?%>L  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens >"z
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens e-UPu%'  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens f{*G%  
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    tlens = 3.767 + 0.04*A                  'Lens thickness -_b}b)2iYN  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction uh
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    'Adjust parameters to account for accommodation Bk?MF6  
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    '************************************************************************* {{@3r5KGl  
    'Aqueous thickness (Position of Lens) D?X97jNm  
    '************************************************************************* 5:^dyF&sm{  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) O23f\pm&  
    GetCustomElement eID, entity
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    parID = FindFullName( "Geometry.Arizona Eye" ) "z@qG]#5  
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    ' Delete any shift(s) in z .hETqE`E  
    count = 0 &*/X*!_HK  
    While GetOperationCount(eID)>count 6`X#<#_&  
        GetOperation eID, count, op $Iqt c)DA  
        If op.Type="ShiftZ" Then /+02BP  
            DeleteOperation eID,count k"GW3E;  
            count=count-1 2&Wc4,O!i  
        End If H^'*F->BA  
        count=count+1 A/BL{ U}  
    Wend W!GgtQw{F  
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    'Set new shift in I-fs*yzj;8  
    op.Type = "ShiftZ" 5hg>2?e9s?  
    op.val1 = taq Fv#ToT:QXe  
    op.parent = parID /c3DltOdr  
    AddOperation eID, op B-r9\fi,  
    Print "Set aqueous humor thickness = " & taq-0.55 `9b D%M  
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    '************************************************************************* IE'OK  
    'Radius and conic constant of anterior lens 1wGd5>GDA  
    '************************************************************************* w;>]L.n  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 1Voo($q.  
    GetConic eID, entity, curv, conic 4y%N(^  
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    SetConic eID, entity, 1/Rant, CCant 8c]\4iau  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 9Z7o?S";  
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    '************************************************************************* h1JG^w$ 5  
    'Radius and conic constant of posterior lens "6Ly?'HK  
    '************************************************************************* uop_bJ  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 1*;?uC\  
    GetConic eID, entity, curv, conic F}i rCi47c  
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    SetConic eID, entity, 1/Rpost, CCpost 3lA<{m;V  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost tEBf2|<  
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    '************************************************************************* ;) (qRZd6  
    'Lens thickness (Position of posterior lens surface) &$vDC M4  
    '************************************************************************* %oC]Rpdu  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) fN8A'p[  
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    ' Delete any z-shift(s) H-7*)D  
    count = 0 J"FKd3~:E  
    While GetOperationCount(eID)>count IExQ}I  
        GetOperation eID, count, op &e3z)h  
        If op.Type="ShiftZ" Then _qJ[~'m<^C  
            DeleteOperation eID,count * Oyic3F  
            count=count-1 8
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        End If $0iz;!w  
        count=count+1 <~X=6  
    Wend &AOw(?2  
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    'Set new z-shift Gash3}+  
    op.Type = "ShiftZ" |~v($c  
    op.val1 = tlens fgTvwOSk  
    op.parent = parID %#ms`"H  
    AddOperation eID, op cGOE$nL  
    Print "Set lens thickness = " & tlens R/<  /g=  
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    '************************************************************************* i!YZF$|  
    'Lens index of refraction `C_#EU-  
    '************************************************************************* fB;'U  
    eID = FindMaterial( "Lens" ) @RbAC*Y]g  
    GetModelMaterial eID, mat )k29mqa`  
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    mat.Nd = nlens g<}EL[9  
    SetModelMaterial eID, mat ^/Gjk  
    Print "Set lens index of refraction = " & nlens AVNB)K"  
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    '************************************************************************* C'7W50b  
    'Pupil diameter vaR0`F  
    '************************************************************************* as~.XWa  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ,<pql!B-  
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    'Adjust pupil diameter (trimming volume inner hole) Z''Fz(qMC  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" f&^Ea-c  
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    ' Adjust pupil location to just in front of the lens ?_n.B=H`8  
    parID = FindFullName( "Geometry.Arizona Eye" ) _mXq]r0  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) EB@!?=0x  
    count = 0 JR7~|ov  
    While GetOperationCount(eID)>count R>pa? tQgK  
        GetOperation eID, count, op Mt@K01MI%  
        If op.Type="ShiftZ" Then fp12-Hk ~  
            DeleteOperation eID,count  s.GTY@t  
            count=count-1 w[4SuD  
        End If O aF+Z@s  
        count=count+1 K"-N:OV  
    Wend \ov>?5  
    op.Type = "ShiftZ" y<3v/,Y  
    op.val1 = taq-0.01 )S8q.h  
    op.parent = parID YhR?*Di  
    AddOperation eID, op {fIH9+v  
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    Print "Set pupil diameter = " & pupilDiam ;CAB.aB~  
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    'Update AZ Eye subassembly Description u$<FKp;I  
    eID = FindFullName( "Geometry.Arizona Eye" ) DgOoEHy[  
    GetEntity eID, entity &[RC4^;\V  
    entity.Description = "Accommodation = " & A & "D" Kau*e8  
    SetEntity eID, entity m{+lG*  
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    Update Wuc,Cjm9(!  
    Print "DONE!" NG5H?hVN=  
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End Sub ^T^U:Zdq  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： 8yztVdh  
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Accommodation = 4 Diopters 5l(;+#3y/  
Pupil Diameter = 4 mm |l)Oy#W  
Set aqueous humor thickness = 2.81 O8dD
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Set anterior lens radius = 10.4 and conic constant = -2.375869 39~fP)  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 ;'J L$=  
Set lens thickness = 3.927 a-%^!pN\M  
Set lens index of refraction = 1.42672 WNL3
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Set pupil diameter = 4 @}fnR(fS  
DONE! $V5Ol6@2  
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