[分享]Arizona眼睛模型 [复制链接]

简介 ~08v]j q  
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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。 4/4IZfznX  
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模型 y~fy0P:T  
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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。 K5$ y  
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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. ;g9+*$Gw  
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光源 O_ cK4  
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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。 k8TMdWW  
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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。 (:1j-  
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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。 H4N==o  
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视网膜的散射 7>nA;F 8_  
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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。 Buo1o&&  
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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。 ,Y*f]  
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脚本 *M="k 1P1  
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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： G~JQcJFj  
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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。 D526X0  
余下的脚本计算与屈光度有关的所有参数。 eRGip2^cq+  
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分析 NYCkYI  
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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。 Rk'Dd4"m,  
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脚本代码 t~Uqsa>n@'  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. $o
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Dim entity As T_ENTITY { "/@,!9rJ  
Dim op As T_OPERATION C}Khh`8@5.  
Dim mat As T_MODELMATERIAL P"- ,^?6  
Dim A As Double 0q/g:"|j  
Dim pupilDiam As Double O6`@'N>6P  
Dim eID As Long E_h9y  
Dim parID As Long k -SUp8}g  
Dim count As Integer UZ<!(g.  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double
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Dim tlens As Double, nlens As Double bNqjjg  
Dim curv As Double, conic As Double 3&}wfK]X  
Dim ok As Long q* m%Fv  
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Sub Main N%`ikdaTd  
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    '用户输入对话框 tnp]wZ  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 bzZEwMc6  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ^7(zoUn:  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 50CU|  
        OKButton 40,91,90,21 r|&qXb x  
        CancelButton 190,91,90,21 0BD3~Lv  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 )2\6Fy0S  
        TextBox 220,49,40,21,.TextBox2 'default: 4 0|d%@
  
    End Dialog *s_)E2  
    Dim dlg As UserDialog nkvzv  
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    ok = Dialog (dlg) ,cpPXcz?,  
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    If ok=0 Then    'cancel button was pressed Ua(!:5q?  
        Print "Execution cancelled." Wvcj\2'yd  
        End wJ+"JQY.J+  
    End If Zr`:A$  
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    'Assign accommodation and pupil diameter & use defaults if field left empty oZ!rK/qoA  
    If dlg.TextBox1 = "" Then Vk[m$  
        A = 0           'Default accommodation $NqT={
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    Else G:f]z;Xdp  
        A = CDbl(dlg.TextBox1) W<kJ%42^j  
    End If "Sl";.  
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    If dlg.TextBox2 = "" Then 2TY|)ltsF  
        pupilDiam = 4   'Default pupil diameter pnDD9u-4;  
    Else /f_lWr:9l  
        pupilDiam = CDbl(dlg.TextBox2) >`u} G1T\  
    End If .|cQ0:B[  
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    Print " " ;Cm%<vW4!  
    Print "Accommodation = " & A & " Diopters" Q;SMwCB0M  
    Print "Pupil Diameter = " & pupilDiam & " mm" sJ!AI n<  
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    ' Calculate new parameters with accommodation 2,'m]`;GNr  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness =3Y?U*d  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 'Aai.PE:  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 7>v1w:cC]  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ]uj6-0q){W  

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    tlens = 3.767 + 0.04*A                  'Lens thickness EnZrnoGM  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 4)i/B99k  
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    'Adjust parameters to account for accommodation u\.7#D>  
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    '************************************************************************* m^%[  
    'Aqueous thickness (Position of Lens) >kd&>)9v  
    '************************************************************************* &Nt4dp`qj  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) aB+Ux< -  
    GetCustomElement eID, entity %5NfF65'  
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    parID = FindFullName( "Geometry.Arizona Eye" ) a>G|t5w  
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    ' Delete any shift(s) in z =4 36/O`K  
    count = 0 p
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    While GetOperationCount(eID)>count e>=P'  
        GetOperation eID, count, op t[XxLG*  
        If op.Type="ShiftZ" Then rB~x]
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            DeleteOperation eID,count D}r,t_]Eb  
            count=count-1 $RfM}!7?  
        End If S1.w^Ccy  
        count=count+1 ^?VYE26  
    Wend {Ug?k<h7|  
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    'Set new shift in pc J5UJY  
    op.Type = "ShiftZ" m$Lq#R={Z  
    op.val1 = taq KW]/u  
    op.parent = parID RHZ5f0b4L  
    AddOperation eID, op .;8T*  
    Print "Set aqueous humor thickness = " & taq-0.55 )4vZIU#  
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    '************************************************************************* PF+v[h;,  
    'Radius and conic constant of anterior lens DJ2EV^D+P  
    '************************************************************************* SxdH%agM  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) A
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    GetConic eID, entity, curv, conic > SU2Jw  
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    SetConic eID, entity, 1/Rant, CCant ]cdKd)  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant nlQ<Aa-%  
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    '************************************************************************* NguJ[  
    'Radius and conic constant of posterior lens wu"6Kyu  
    '************************************************************************* jO)UK.H#  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ;I1}g]  
    GetConic eID, entity, curv, conic EbZRU65J}O  
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    SetConic eID, entity, 1/Rpost, CCpost fgVeB;k|  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost  c %w h  
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    '************************************************************************* $@<qaR{t\  
    'Lens thickness (Position of posterior lens surface) }J"}5O2,b  
    '************************************************************************* UT|FV twO  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) L s6P<"V  
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    ' Delete any z-shift(s) Yj99[ c#]  
    count = 0 ,iY/\ U''  
    While GetOperationCount(eID)>count c+|,qm  
        GetOperation eID, count, op c%%r  
        If op.Type="ShiftZ" Then |-GmWSK_  
            DeleteOperation eID,count :SjTkfU  
            count=count-1 P#H|at  
        End If I?nj_ as  
        count=count+1 m_{OCHS+  
    Wend
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    'Set new z-shift f|G,pDLx  
    op.Type = "ShiftZ" eJFGgJRIvF  
    op.val1 = tlens I%.KFPV  
    op.parent = parID t>p!qKrE'J  
    AddOperation eID, op  Cg[]y1Ne  
    Print "Set lens thickness = " & tlens q{I,i(%m8  
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    '************************************************************************* <;}jf*A  
    'Lens index of refraction oxT..=-  
    '************************************************************************* 7DaMuh~<  
    eID = FindMaterial( "Lens" ) PI@/jh  
    GetModelMaterial eID, mat 6z3 Yq{1  
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    mat.Nd = nlens mGR}hsQpn  
    SetModelMaterial eID, mat P[{qp8(g  
    Print "Set lens index of refraction = " & nlens )vVt{g  
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    '************************************************************************* Y Y4"r\V  
    'Pupil diameter s6Ox!)&  
    '************************************************************************* _q*4+x  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) *c'nPa$+|S  
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    'Adjust pupil diameter (trimming volume inner hole) f@U\2r  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" `QC  
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    ' Adjust pupil location to just in front of the lens F)P"UQ!\  
    parID = FindFullName( "Geometry.Arizona Eye" ) %Ci`OhT  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) '6U~|d  
    count = 0 <-KHy`u  
    While GetOperationCount(eID)>count h&Thq52R  
        GetOperation eID, count, op R'bmE:nL  
        If op.Type="ShiftZ" Then za{z2#aJ  
            DeleteOperation eID,count =*EIe z*.x  
            count=count-1 Fr{u=0 X  
        End If Ckd=tvL  
        count=count+1 c"qaULY  
    Wend Exir?G}\  
    op.Type = "ShiftZ" 90JD`Nz
 
    op.val1 = taq-0.01 0uX"KL]Elf  
    op.parent = parID `CCuwe<v  
    AddOperation eID, op a#H2H`%  
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    Print "Set pupil diameter = " & pupilDiam n#@/A  
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    'Update AZ Eye subassembly Description !O=
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    eID = FindFullName( "Geometry.Arizona Eye" ) {ctEjgiE  
    GetEntity eID, entity ~x<nz/^  
    entity.Description = "Accommodation = " & A & "D" jIY   
    SetEntity eID, entity "-aak )7w  
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    Update :|hFpLt  
    Print "DONE!" RiHOX&-7  
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End Sub 7P3PQ%:  
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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： l5sBDiir%  
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Accommodation = 4 Diopters QmQsNcF~z  
Pupil Diameter = 4 mm 3w&fN3 1  
Set aqueous humor thickness = 2.81 $Pa7B]A,Ae  
Set anterior lens radius = 10.4 and conic constant = -2.375869 I5RV:e5b  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 :1%z;  
Set lens thickness = 3.927 .Q'/e>0  
Set lens index of refraction = 1.42672 w k1O*_76  
Set pupil diameter = 4 Wtl0qug  
DONE! gH87e  
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