[分享]Arizona眼睛模型 [复制链接]

简介 #gz M|  
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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。 $c0h.t  
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模型 B8f8w)m  
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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。 #$18*?tLv|  
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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. W-mQjJ`,B  
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光源 @;*Ksy@1O  
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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。 #Y

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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。 (;T^8mI2  
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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。 hs^zTZ_  
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视网膜的散射 [<n2Uz7MP  
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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。
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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。 _K]_ @Ivh  
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脚本 R%{<mno/_  
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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： CAfGH!l!  
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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。 0(eBZdRO  
余下的脚本计算与屈光度有关的所有参数。 "|EM;o  
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分析 <c2E'U)X  
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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。 %Qmn-uZ  
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脚本代码 NP0\i1P>.?  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. r(:5kC8K  
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Dim entity As T_ENTITY N-G1h?e4  
Dim op As T_OPERATION * aN  
Dim mat As T_MODELMATERIAL 8[
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Dim A As Double qB5j;@r  
Dim pupilDiam As Double IdzxS  
Dim eID As Long
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Dim parID As Long F0GxH?  
Dim count As Integer p*< 0"0  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double H=<S 9M  
Dim tlens As Double, nlens As Double 8m-U){r!U^  
Dim curv As Double, conic As Double g2BHHL;`  
Dim ok As Long d(\%Os  
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Sub Main HHA<IZ#;,  
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    '用户输入对话框 CuFSeRe  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 '.on)Zd.  
        TextBox 220,21,40,21,.TextBox1 'default: 0 U_Vs.M.p  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 &q3"g*q  
        OKButton 40,91,90,21 E%yNa]\P  
        CancelButton 190,91,90,21 @Pm>sY}d<I  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 N@2dA*T,  
        TextBox 220,49,40,21,.TextBox2 'default: 4 +NeOSQSj  
    End Dialog /$i.0$L  
    Dim dlg As UserDialog v_BcTzQ0S  
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    ok = Dialog (dlg) rV2WnAb[H&  
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    If ok=0 Then    'cancel button was pressed G/k2Pe{SL  
        Print "Execution cancelled." <lgYcdJ   
        End P0SQr?W  
    End If S'k_olx7  
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    'Assign accommodation and pupil diameter & use defaults if field left empty _>5(iDW0  
    If dlg.TextBox1 = "" Then VyXKZ%\dQ/  
        A = 0           'Default accommodation VF&(8X\   
    Else /sUYU(3  
        A = CDbl(dlg.TextBox1) xu>9(,l  
    End If 2POXj!N  
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    If dlg.TextBox2 = "" Then [glLre^  
        pupilDiam = 4   'Default pupil diameter s6H]J{1F  
    Else wVX[)E\J  
        pupilDiam = CDbl(dlg.TextBox2) 8LyD7P1\  
    End If ]q;Emy  
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    Print " " O(#)m>A  
    Print "Accommodation = " & A & " Diopters" #pT"BSz]  
    Print "Pupil Diameter = " & pupilDiam & " mm" Pj[PIz  
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    ' Calculate new parameters with accommodation ({
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    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness %<)2/|lCd  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens Ye\rB\-  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens rxVanDb=W  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 4~ q5,^kgB  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens )YYf1o[+  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 8Ry3`ct  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction L
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    'Adjust parameters to account for accommodation ",p;Sd  
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    '************************************************************************* bo,_&4?  
    'Aqueous thickness (Position of Lens) 0m7Y>0wC6T  
    '************************************************************************* QMA%$  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) S$f9m  
    GetCustomElement eID, entity 5<iV2H
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    parID = FindFullName( "Geometry.Arizona Eye" ) +cD<:"L'
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    ' Delete any shift(s) in z O6Vtu Ws%  
    count = 0 b1?#81  
    While GetOperationCount(eID)>count P]<4R:yb  
        GetOperation eID, count, op `uq8G  
        If op.Type="ShiftZ" Then 8/DS:uM  
            DeleteOperation eID,count y>R=`A1b  
            count=count-1 Ot$-!Y;<  
        End If [=x[ w70  
        count=count+1 Bt[/0>i  
    Wend 3T31kQv{  
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    'Set new shift in K}2Erm%A@y  
    op.Type = "ShiftZ" AG3>V+k{Lv  
    op.val1 = taq LnFdhrB@x  
    op.parent = parID x* DarSk  
    AddOperation eID, op "HX<,l8f%  
    Print "Set aqueous humor thickness = " & taq-0.55 }xKP~h'F  
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    '************************************************************************* t$+?6E  
    'Radius and conic constant of anterior lens }Dp*}=?E  
    '************************************************************************* 9lTv   
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ".f ;+wH  
    GetConic eID, entity, curv, conic *xc_k
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    SetConic eID, entity, 1/Rant, CCant -Q2, "  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant > pgX^  
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    '************************************************************************* DDvh4<
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    'Radius and conic constant of posterior lens !y#"l$"xK  
    '************************************************************************* +[Dj5~V  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) |VKK#J/  
    GetConic eID, entity, curv, conic oYHj~t  
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    SetConic eID, entity, 1/Rpost, CCpost z^KJ*E  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost -)s qc P  
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    '************************************************************************* 6~OoFm5  
    'Lens thickness (Position of posterior lens surface) g6nkZyw  
    '************************************************************************* p$SX  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 5&xB6|k  
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    ' Delete any z-shift(s) -VZ-<\uH  
    count = 0 3E7ULK  
    While GetOperationCount(eID)>count Ytgcs( /$  
        GetOperation eID, count, op -HQQw$  
        If op.Type="ShiftZ" Then >82@Q^O  
            DeleteOperation eID,count %el"BSB  
            count=count-1 UsgK  
        End If })uGRvz  
        count=count+1 Z/Eb:  
    Wend ]d55m/(   
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    'Set new z-shift +nUy,S?43  
    op.Type = "ShiftZ" DvME1]7)  
    op.val1 = tlens z25lZI" X`  
    op.parent = parID QFfK0X8cC  
    AddOperation eID, op k $M]3}$U  
    Print "Set lens thickness = " & tlens 4f@o m
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    '************************************************************************* h1:aKm!  
    'Lens index of refraction "ZHW2l Mf  
    '************************************************************************* Cv }Qwy  
    eID = FindMaterial( "Lens" ) ktI/3Mb@  
    GetModelMaterial eID, mat Xf0M:\w=M  
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    mat.Nd = nlens YNYx>Ue  
    SetModelMaterial eID, mat ! N|0x
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    Print "Set lens index of refraction = " & nlens 33jovK2  
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    '************************************************************************* H&F9J^rC  
    'Pupil diameter ilK-?@u+  
    '************************************************************************* cQG +$0(  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 1[kMOp  
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    'Adjust pupil diameter (trimming volume inner hole) CxGx8*
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" G,TM-l_uw  
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    ' Adjust pupil location to just in front of the lens YRv&1!VLE  
    parID = FindFullName( "Geometry.Arizona Eye" ) tcI}Ca>u  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" )
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    count = 0 &P.4(1sC  
    While GetOperationCount(eID)>count "dsU>3u  
        GetOperation eID, count, op +${D  
        If op.Type="ShiftZ" Then 6Z#\CixG  
            DeleteOperation eID,count lJ+0P2@h*  
            count=count-1 *J$=.fF1  
        End If PpV'F[|,r  
        count=count+1 qZ]pq2G  
    Wend F&])P- !3  
    op.Type = "ShiftZ" .udv"?!z  
    op.val1 = taq-0.01 $k0k
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    op.parent = parID z?>D_NLX6  
    AddOperation eID, op h8 'v d3  
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    Print "Set pupil diameter = " & pupilDiam Wqc)Fv70m  
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    'Update AZ Eye subassembly Description p>vn7;s2#  
    eID = FindFullName( "Geometry.Arizona Eye" ) !icT/5  
    GetEntity eID, entity Kk(9O06j  
    entity.Description = "Accommodation = " & A & "D" 'D6T8B4  
    SetEntity eID, entity aaKN^fi&  
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    Update I<Ksi~*i  
    Print "DONE!" Qd=^S^}(  
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End Sub J
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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： }K1JU`Lz  
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Accommodation = 4 Diopters 4Y,R-+f
 
Pupil Diameter = 4 mm 3 N7[.I>A  
Set aqueous humor thickness = 2.81 0`)iIz  
Set anterior lens radius = 10.4 and conic constant = -2.375869 so)"4 SEu  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 I&MY{f  
Set lens thickness = 3.927 WX}xmtLs  
Set lens index of refraction = 1.42672 )'/|)  
Set pupil diameter = 4 @o#!EfZyE  
DONE! SfJA(v@E  
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