[分享]Arizona眼睛模型 [复制链接]

简介 j_?cpm{~ml  
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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。 HW=xvA+  
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模型 )Du-_Z  
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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。 go)p%}s  
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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. nN`"z3o  
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光源 @kngI7=E  
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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。 >3;^l/2c  
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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。 RagiV6c  
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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。 n~z\?Y=*  
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视网膜的散射 [J\DB)V/  
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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。 7{BnXN[  
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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。 \v`#|lT$  
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脚本 9EgP9up{6!  
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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： &zN@5m$k;  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 n!.2aq  
余下的脚本计算与屈光度有关的所有参数。 nTZ> |R)  
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分析 Vq}r_#!Q  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 (L#%!bd  
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脚本代码 *C_[jk@6  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. ?vu|o'$T,  
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Dim entity As T_ENTITY nUqy1(  
Dim op As T_OPERATION VN|G5*  
Dim mat As T_MODELMATERIAL ]V<"(?,K  
Dim A As Double B T7Id  
Dim pupilDiam As Double hPPB45^  
Dim eID As Long V<-htV  
Dim parID As Long ;QidDi_s>  
Dim count As Integer ;5M<j3_*  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double A7'bNd6f9  
Dim tlens As Double, nlens As Double "-U3
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Dim curv As Double, conic As Double ]31$KBC  
Dim ok As Long 
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Sub Main }N|\   
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    '用户输入对话框 !Zj#
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    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 6K//1U$  
        TextBox 220,21,40,21,.TextBox1 'default: 0 YKq0f=Ij  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 %]GV+!3S  
        OKButton 40,91,90,21 ('HxHOh2  
        CancelButton 190,91,90,21 ;.0LRWcJ  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 q2Rf@nt  
        TextBox 220,49,40,21,.TextBox2 'default: 4 =~",/I?  
    End Dialog a>(~C
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    Dim dlg As UserDialog BvI 0v:  
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    ok = Dialog (dlg) 'fl(N2t  
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    If ok=0 Then    'cancel button was pressed &E]"c]i+  
        Print "Execution cancelled." Bt6xV<jD  
        End EOQaY  
    End If ~*kK4]lP  
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    'Assign accommodation and pupil diameter & use defaults if field left empty =SL^>HS.fo  
    If dlg.TextBox1 = "" Then I}ndRDz[  
        A = 0           'Default accommodation Cg*kN"8q  
    Else }6@%((9E2  
        A = CDbl(dlg.TextBox1) (k#t}B[  
    End If %Y 2G  
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    If dlg.TextBox2 = "" Then n531rkK-   
        pupilDiam = 4   'Default pupil diameter (ic@
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    Else 5E.vje{U
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        pupilDiam = CDbl(dlg.TextBox2) Q6|@N~UeZ  
    End If q!@c_o  
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    Print " " ]eD[4Y\#t  
    Print "Accommodation = " & A & " Diopters" \aB&{`iG  
    Print "Pupil Diameter = " & pupilDiam & " mm" ja:\W\xhJ  
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    ' Calculate new parameters with accommodation v<`$bvv?  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 3m~U(yho  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens BMF3XcH~G  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens r=|vad$  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens }R\B.2#M_@  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ~"\P~cg0J  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Hj1k-Bs&'w  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 78gob&p?  
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    'Adjust parameters to account for accommodation )biX8yqhR  
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    '************************************************************************* '2j~WUEmg  
    'Aqueous thickness (Position of Lens) cUYX1a)8  
    '************************************************************************* z^"?sd  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Km%8Yw0+  
    GetCustomElement eID, entity ayN*fiV]  
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    parID = FindFullName( "Geometry.Arizona Eye" ) )~G8 LZ  
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    ' Delete any shift(s) in z miWw6!()  
    count = 0 5,Qy/t}K  
    While GetOperationCount(eID)>count :E}6S  
        GetOperation eID, count, op P%ye$SASd  
        If op.Type="ShiftZ" Then  hgNY[,  
            DeleteOperation eID,count e-1;dX HL  
            count=count-1 z)r8?9u  
        End If wX@H &)<s  
        count=count+1 _8Pmv$   
    Wend ?
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    'Set new shift in 5X#i65_-  
    op.Type = "ShiftZ" hwc:@'  
    op.val1 = taq 8U8P g2  
    op.parent = parID .Ydr[  
    AddOperation eID, op oXvdR(Sb^  
    Print "Set aqueous humor thickness = " & taq-0.55 8a_ UxB  
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    '************************************************************************* f;&` 9s| 1  
    'Radius and conic constant of anterior lens }3LBbG0Bw  
    '************************************************************************* Fa6H(L3  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) r{bg
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    GetConic eID, entity, curv, conic '3IkPy1Uz  
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    SetConic eID, entity, 1/Rant, CCant &IIJKn|_  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant VZAuUw+M  
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    '************************************************************************* f6@^
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    'Radius and conic constant of posterior lens IY-(- a8  
    '************************************************************************* dw@TbJ  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) h2im sjf  
    GetConic eID, entity, curv, conic >aNbp  
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    SetConic eID, entity, 1/Rpost, CCpost ~5x4?2  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost {Q}!NkF1  
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    '************************************************************************* #JHy[!4  
    'Lens thickness (Position of posterior lens surface) IptB.bYc  
    '************************************************************************* V.O<|tl.  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) $w 5#2Za  
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    ' Delete any z-shift(s) "H wVK  
    count = 0 ,<R>Hiwg/s  
    While GetOperationCount(eID)>count |?4~T:  
        GetOperation eID, count, op Nv}U/$$S  
        If op.Type="ShiftZ" Then Uqb
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            DeleteOperation eID,count P]~N-xdV  
            count=count-1 Z1XUYe62  
        End If (CKhY~,/u  
        count=count+1 * ePDc'   
    Wend G~b`O20N  
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    'Set new z-shift 5?#OR!N  
    op.Type = "ShiftZ" FU [8:o62  
    op.val1 = tlens # CP9^R S  
    op.parent = parID lq78gOg{  
    AddOperation eID, op bn^mL~  
    Print "Set lens thickness = " & tlens x9FLr}e  
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    '*************************************************************************
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    'Lens index of refraction y@2vY[)3s  
    '************************************************************************* &etL&s v  
    eID = FindMaterial( "Lens" ) e _SoM!;  
    GetModelMaterial eID, mat %RfY`n  
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    mat.Nd = nlens VuJfo9 `E  
    SetModelMaterial eID, mat 1Ovx$*  
    Print "Set lens index of refraction = " & nlens tkm~KLWV&7  
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    '************************************************************************* wI1M0@}PV  
    'Pupil diameter 8.q13t!D  
    '************************************************************************* ,u8ZS|9  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) xr7-[)3Q$  
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    'Adjust pupil diameter (trimming volume inner hole) "Gi+zkVm  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" U#UVenp@  
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    ' Adjust pupil location to just in front of the lens ArEH%e  
    parID = FindFullName( "Geometry.Arizona Eye" ) X$j|/))  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) n;S0fg  
    count = 0  Xv? S  
    While GetOperationCount(eID)>count gnKU\>2k  
        GetOperation eID, count, op O|^6UH  
        If op.Type="ShiftZ" Then @@&@}IQcR1  
            DeleteOperation eID,count On2Vf*G@|  
            count=count-1 <.?^LT  
        End If 
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        count=count+1 C[J`x>-K  
    Wend O;&yA<  
    op.Type = "ShiftZ" ino7!T`  
    op.val1 = taq-0.01 o%N0K  
    op.parent = parID gOES2 4$2  
    AddOperation eID, op ]6i_d  
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    Print "Set pupil diameter = " & pupilDiam m\}\RnZu  
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    'Update AZ Eye subassembly Description fd,}YAiX  
    eID = FindFullName( "Geometry.Arizona Eye" ) ;k63RNT,M&  
    GetEntity eID, entity e
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    entity.Description = "Accommodation = " & A & "D" $J;=Ux)$  
    SetEntity eID, entity vt(}ga  
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    Update EkgN6S`}  
    Print "DONE!" Rm[rQ}:  
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End Sub
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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： :+Z>nHe  
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Accommodation = 4 Diopters =%nqMV(y  
Pupil Diameter = 4 mm EiIFVP   
Set aqueous humor thickness = 2.81 ;>QK}
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Set anterior lens radius = 10.4 and conic constant = -2.375869 Lu#@~  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 m?kIa!GM=  
Set lens thickness = 3.927 lG[ )8!:+  
Set lens index of refraction = 1.42672 Um0<I)  
Set pupil diameter = 4 vI:bl~  
DONE! H?/cG_^y0  
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