[技术]Arizona眼睛模型 [复制链接]

简介 E4r.ky`#~  
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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。 ]BfS270  
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模型 r?pZ72q  
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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。 X]!D;7^  
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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. C`NmZ
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光源 )7dEi+v52  
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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。 +%XnMl  

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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。 .xl.P7@JJ  
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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。 )t%h[0{{  
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视网膜的散射 Efx=T$%^&  
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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。 t`YWwI.  
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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。 _R^y\1Qu  
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脚本 L^FcS\r;  
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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： 9i=B  
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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。 =K(JqSw+M  
余下的脚本计算与屈光度有关的所有参数。 8sg|MWSU  
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分析 '#D8*OP^  
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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。 0%<+J;'o  
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脚本代码 eT[&L @l]b  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. x[X`a  
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Dim entity As T_ENTITY I[D8""U  
Dim op As T_OPERATION ER^QV(IvP8  
Dim mat As T_MODELMATERIAL #U ASH&  
Dim A As Double E\M-k\cSj  
Dim pupilDiam As Double $1Z6\G O  
Dim eID As Long e2w&&B-  
Dim parID As Long HBiBv-=,  
Dim count As Integer mgQIhXH5L  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Ef@,hX  
Dim tlens As Double, nlens As Double 5 1dSFr<#  
Dim curv As Double, conic As Double Ri)uq\E/#  
Dim ok As Long vt1lR5  
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Sub Main x({C(Q'O  
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    '用户输入对话框 L/Vx~r`P  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 2@khSWV  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ke%pZ7{u  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 F)Oe9x\/  
        OKButton 40,91,90,21 :O-1rD  
        CancelButton 190,91,90,21 F9flSeN  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 %J~WC$=Qv  
        TextBox 220,49,40,21,.TextBox2 'default: 4 pqR\>d0  
    End Dialog m3.sVI0I  
    Dim dlg As UserDialog -VT+O+9_A  
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    ok = Dialog (dlg) 9 OT,TpA  
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    If ok=0 Then    'cancel button was pressed 9Q.#\  
        Print "Execution cancelled." L,LNv  
        End 6b=q-0yj  
    End If Vba.uKNjk  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ae+*=,  
    If dlg.TextBox1 = "" Then $}o b,i^W  
        A = 0           'Default accommodation -{jdn%Y7CK  
    Else F]+~x/!  
        A = CDbl(dlg.TextBox1) y2|R.EU\m<  
    End If R 94
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    If dlg.TextBox2 = "" Then `{Tk@A_yd  
        pupilDiam = 4   'Default pupil diameter K8I$]M  
    Else `[fxyg:u  
        pupilDiam = CDbl(dlg.TextBox2) fV\]L4%  
    End If rS8 w\`_  
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    Print " " :i
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    Print "Accommodation = " & A & " Diopters" # Su~`]  
    Print "Pupil Diameter = " & pupilDiam & " mm" gVR@&bi7  
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    ' Calculate new parameters with accommodation WyhhCR=;  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness B&?sF" Y  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens $ &UZy|9  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens PkuTg";  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens }^kL|qmjR  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Cb;WZ3HR  
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    tlens = 3.767 + 0.04*A                  'Lens thickness #]Y>KX2HG  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction q(M:QWA q  
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    'Adjust parameters to account for accommodation cmwPu
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    '************************************************************************* 9ooY?J  
    'Aqueous thickness (Position of Lens) dtt~ Bd  
    '************************************************************************* ?Bi*1V<R  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) muON>^MbC  
    GetCustomElement eID, entity D<$Xy
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    parID = FindFullName( "Geometry.Arizona Eye" ) V9NTs8LKc  
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    ' Delete any shift(s) in z *iA4:EIP  
    count = 0 \*t~==WB
 
    While GetOperationCount(eID)>count $.%rAa_H  
        GetOperation eID, count, op !^c@shLN4  
        If op.Type="ShiftZ" Then l! bv^  
            DeleteOperation eID,count ]b?9zeT*'l  
            count=count-1 k(VB+k"3  
        End If s@
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        count=count+1 e.d #wyeX  
    Wend Hh;:`;}  
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    'Set new shift in T#@lDpO  
    op.Type = "ShiftZ"
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    op.val1 = taq 
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    op.parent = parID cf_|nL#9  
    AddOperation eID, op U&Wwyu:4i  
    Print "Set aqueous humor thickness = " & taq-0.55 CTa#Q,  
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    '************************************************************************* jhgX{xc  
    'Radius and conic constant of anterior lens T4/fdORS  
    '************************************************************************* T=f|,sK +7  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Ga>uFb}W~  
    GetConic eID, entity, curv, conic CBYX]  
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    SetConic eID, entity, 1/Rant, CCant ;h=*!7:  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant <yA}i"-1W  
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    '************************************************************************* zdl%iop3
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    'Radius and conic constant of posterior lens 6Q&r0>^{  
    '************************************************************************* hOv={:  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) qVqRf.-\  
    GetConic eID, entity, curv, conic xiF7}]d+  
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    SetConic eID, entity, 1/Rpost, CCpost /'2O.d0}.  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ^jB8Q  
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    '************************************************************************* DhLqhME53  
    'Lens thickness (Position of posterior lens surface) 6d[_G$'nk  
    '************************************************************************* ,fDEz9-,  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) _ZB\L^j)  
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    ' Delete any z-shift(s) Di_2Plo)4  
    count = 0 -ezY=0Q&  
    While GetOperationCount(eID)>count F7L&=K$2y  
        GetOperation eID, count, op -{XRA
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        If op.Type="ShiftZ" Then thi1kJ`L  
            DeleteOperation eID,count |'ln?D:&  
            count=count-1 5<pftTcZ  
        End If 5vAf7\*  
        count=count+1 u=F+(NE"  
    Wend hf/2vt m  
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    'Set new z-shift /M~!sPW&?  
    op.Type = "ShiftZ" Zv_.na/^K  
    op.val1 = tlens , ^F)L|  
    op.parent = parID |s#'dS;  
    AddOperation eID, op UUK
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    Print "Set lens thickness = " & tlens #PDf,^
 
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    '************************************************************************* Yb i%od&  
    'Lens index of refraction W!blAkM%i  
    '************************************************************************* uJHu>M}~  
    eID = FindMaterial( "Lens" )
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    GetModelMaterial eID, mat YIt& >  
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    mat.Nd = nlens RgorkZlVM  
    SetModelMaterial eID, mat ,mS/h~-5n  
    Print "Set lens index of refraction = " & nlens <e]Oa$  
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    '************************************************************************* P&d"V<  
    'Pupil diameter Q-Ux<#
  
    '************************************************************************* %<?0apO  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Flf
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    'Adjust pupil diameter (trimming volume inner hole) k%wn0Erd  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" .@-9'<K?~  
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    ' Adjust pupil location to just in front of the lens `nKH"TaX  
    parID = FindFullName( "Geometry.Arizona Eye" ) KfBTL!0#  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) YSJy`  
    count = 0 IKMeJ(:S  
    While GetOperationCount(eID)>count id<:p*  
        GetOperation eID, count, op +X`V|E,no  
        If op.Type="ShiftZ" Then ANIz,LS  
            DeleteOperation eID,count ^_5L"F]sP  
            count=count-1 IM$2VlC  
        End If #po5_dE\*  
        count=count+1 zWpqJK   
    Wend FJ*i\Q/D  
    op.Type = "ShiftZ" 1Gt/Tq$_b  
    op.val1 = taq-0.01 {7cX#1  
    op.parent = parID )&era` e[  
    AddOperation eID, op P o jmC  
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    Print "Set pupil diameter = " & pupilDiam |9"p|6G?B  
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    'Update AZ Eye subassembly Description `c/*H29  
    eID = FindFullName( "Geometry.Arizona Eye" ) 6.5T/D*TT  
    GetEntity eID, entity dC
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    entity.Description = "Accommodation = " & A & "D" *5zrZ]^  
    SetEntity eID, entity !zPG?q]3  
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    Update 2j(h+?N7k  
    Print "DONE!" nd;fy$<J\  
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End Sub -",=G\XZ  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： K =.%$A  
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Accommodation = 4 Diopters S$f6a'  
Pupil Diameter = 4 mm J--m[X  
Set aqueous humor thickness = 2.81 h8\  T  
Set anterior lens radius = 10.4 and conic constant = -2.375869 [Q\GxX.  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 r]W  
Set lens thickness = 3.927 ?[*0+h`en  
Set lens index of refraction = 1.42672 `cx]e  
Set pupil diameter = 4 U yw-2]!n  
DONE! '(f/~"9B