[技术]Arizona眼睛模型 [复制链接]

简介 F<'@T,LVc  
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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。 9UD~$_<\  
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模型 &yFt@g]  
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模型的定义如表1种所示，由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度（A）来决定。 `WDN T0@M  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. Z4U8~i  
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光源 &%QtUPvr9  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 7r=BGoA2E  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 vh8{*9+  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 /aa'ryl_%  
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视网膜的散射 4%#C _pE9  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 gie}k)&M  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 w{$t:l)2,  
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脚本 cES3<`[K  
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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： Z/=x(I0  
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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。 RFyeA. N  
余下的脚本计算与屈光度有关的所有参数。 u
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分析 ;5 W|#{I  
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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。 3| 5Af  
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脚本代码 Lx&2)  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. <'H^}gQow  
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Dim entity As T_ENTITY CA[-\>J7y  
Dim op As T_OPERATION Hf P2o5-  
Dim mat As T_MODELMATERIAL Qn>0s  
Dim A As Double pNFL;k+p}  
Dim pupilDiam As Double @A(*&PU>j  
Dim eID As Long :4|W;Lkd!  
Dim parID As Long wkm;yCF+  
Dim count As Integer Nq>74q]}n8  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ;2K_u  
Dim tlens As Double, nlens As Double OF^v;4u  
Dim curv As Double, conic As Double E )D*~2o/  
Dim ok As Long VZNMom,Wr  
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Sub Main f1F#U@U  
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    '用户输入对话框 d[ql7  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 =\Td~

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        TextBox 220,21,40,21,.TextBox1 'default: 0 &d]%b`EXq  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 B5"(NJ;  
        OKButton 40,91,90,21
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        CancelButton 190,91,90,21 }9[E+8L1
 
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 2<Lnfc<^k  
        TextBox 220,49,40,21,.TextBox2 'default: 4 F"xD^<i  
    End Dialog ]8*#%^  
    Dim dlg As UserDialog Y85M$]e,  
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    ok = Dialog (dlg) `(A>7;]:  
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    If ok=0 Then    'cancel button was pressed _W]qV2j  
        Print "Execution cancelled." h32QEz-+  
        End (i4=}Kn2  
    End If g+h)s!$sB  
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    'Assign accommodation and pupil diameter & use defaults if field left empty zk8s?$  
    If dlg.TextBox1 = "" Then /I|.^ Id|  
        A = 0           'Default accommodation -d?9Acd  
    Else h?[3{Z^  
        A = CDbl(dlg.TextBox1) hmJ{'D1"  
    End If B:dk>$>uQ  
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    If dlg.TextBox2 = "" Then T% J;~|  
        pupilDiam = 4   'Default pupil diameter i_?";5B"  
    Else 7)sEW#d!  
        pupilDiam = CDbl(dlg.TextBox2) /7#KkMg  
    End If mB&nN+MV  
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    Print " " =pQA!u]QE  
    Print "Accommodation = " & A & " Diopters" NBzyP)2)  
    Print "Pupil Diameter = " & pupilDiam & " mm" 1SoKnfz{6  
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    ' Calculate new parameters with accommodation /Y:1zLs%  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness v2R41*z,  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 
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    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 6@kKr  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens o, e y.  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens j&n][=PL  
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    tlens = 3.767 + 0.04*A                  'Lens thickness e6n1/TtqM  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ncS.~F
 
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    'Adjust parameters to account for accommodation ^znj
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    '************************************************************************* /MHqt=jP6  
    'Aqueous thickness (Position of Lens) 6||zwwk'.  
    '************************************************************************* 1;E[Ml  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) JJJlgr]#  
    GetCustomElement eID, entity gIrVrAV#  
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    parID = FindFullName( "Geometry.Arizona Eye" ) }}Ah-QU  
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    ' Delete any shift(s) in z J5Rr7=:*S  
    count = 0 NQefrof  
    While GetOperationCount(eID)>count [OJ@{{U%  
        GetOperation eID, count, op ^)=c74;;  
        If op.Type="ShiftZ" Then \z!*)v/{-  
            DeleteOperation eID,count A[L+
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            count=count-1 %jEdgD%xV  
        End If S%n5,vwE  
        count=count+1 5P_%Vp`B2  
    Wend N\b%+vR  
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    'Set new shift in .QX|:]|n  
    op.Type = "ShiftZ" Ijq',@jE  
    op.val1 = taq s>`$]6wPa  
    op.parent = parID C$`z23E  
    AddOperation eID, op Ys,}L.  
    Print "Set aqueous humor thickness = " & taq-0.55 /zZ$<mVG  
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    '************************************************************************* \M^L'Mkj  
    'Radius and conic constant of anterior lens w6>'n }  
    '************************************************************************* S N_!o2F2  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) =1g
  
    GetConic eID, entity, curv, conic y05(/NH>  
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    SetConic eID, entity, 1/Rant, CCant $(v1q[ig  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant `btw*{.[  
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    '************************************************************************* [G:wPp.y  
    'Radius and conic constant of posterior lens $7~k#_#PC  
    '************************************************************************* ?,e7v.b
 
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 
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    GetConic eID, entity, curv, conic q:N"mp<%  
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    SetConic eID, entity, 1/Rpost, CCpost |GgFdn`>  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost v,w/g|  
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    '************************************************************************* s>d@=P>R  
    'Lens thickness (Position of posterior lens surface) ?H8w/{J   
    '************************************************************************* ?2hoY  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) tWL3F?wd  
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    ' Delete any z-shift(s) "3CQ0  
    count = 0 7eb^^a?  
    While GetOperationCount(eID)>count f?: o  
        GetOperation eID, count, op -1t"(v  
        If op.Type="ShiftZ" Then qk~ni8  
            DeleteOperation eID,count B4AV ubMbe  
            count=count-1 O o9 ePw7  
        End If 0/?V _  
        count=count+1 '6i"pJ0%  
    Wend Arh0m. w  
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    'Set new z-shift PY=(|2tb4  
    op.Type = "ShiftZ" I3uS?c  
    op.val1 = tlens 82#7TX4  
    op.parent = parID mk?&`_X1  
    AddOperation eID, op 4Z>KrFO  
    Print "Set lens thickness = " & tlens {J3;4p-&  
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    '************************************************************************* 8Z{&b,Y4L  
    'Lens index of refraction c
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    '************************************************************************* 9%aBW7@SK  
    eID = FindMaterial( "Lens" ) B-`d7c5  
    GetModelMaterial eID, mat bmN'{09@  
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    mat.Nd = nlens j4H]HGHv  
    SetModelMaterial eID, mat CDcZ6.f  
    Print "Set lens index of refraction = " & nlens 7Pspx'u  
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    '************************************************************************* @ht= (Jk9  
    'Pupil diameter T+p?VngF  
    '*************************************************************************
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) [5Zs%!Z;8N  
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    'Adjust pupil diameter (trimming volume inner hole) #DjSS.iW  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" @{16j#'R  
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    ' Adjust pupil location to just in front of the lens Htd-E^/
 
    parID = FindFullName( "Geometry.Arizona Eye" ) x]o~ %h$  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 5.!iVyN  
    count = 0 UMsJg7~  
    While GetOperationCount(eID)>count jA@jsv  
        GetOperation eID, count, op n$B SO  
        If op.Type="ShiftZ" Then |r2U4^  
            DeleteOperation eID,count k?-GI[@X  
            count=count-1 2LS
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        End If AA[(rw  
        count=count+1
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    Wend 297X).  
    op.Type = "ShiftZ" LbX>@2(&  
    op.val1 = taq-0.01 @H%)!f]zWt  
    op.parent = parID E`68Z/%  
    AddOperation eID, op JL0>-kg  
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    Print "Set pupil diameter = " & pupilDiam A2 'W  
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    'Update AZ Eye subassembly Description 7,0^|P  
    eID = FindFullName( "Geometry.Arizona Eye" ) .bcoH  
    GetEntity eID, entity )`;Q]?D   
    entity.Description = "Accommodation = " & A & "D" 1b*
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    SetEntity eID, entity 49S*f  
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    Update XV)<Oavs  
    Print "DONE!" 9K~0:c  
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End Sub _XLGX
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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： >fG=(1"  
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Accommodation = 4 Diopters J_PAWW  
Pupil Diameter = 4 mm Wtl/xA_  
Set aqueous humor thickness = 2.81 BPgY_f  
Set anterior lens radius = 10.4 and conic constant = -2.375869 OCR`1  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 (C{l4  
Set lens thickness = 3.927 ?\|QDJXY  
Set lens index of refraction = 1.42672 )UBU|uYR\  
Set pupil diameter = 4 zx<:1nF,]  
DONE! KtTlc#*KU