[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 =cKk3kJC  
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。 Cg\)BHv~  
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模型 YK+Z0ry  
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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。 "u]Fl+c  
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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. __n"DLW  
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光源 IlL   
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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。 COL8YY  
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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。 ^yZSCrPGI  
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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。 .MPOUo/e  
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视网膜的散射 vCo}-b-j  
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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。 5e8-?w%e  
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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。 D.x
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脚本 yXl.Gq>]{  
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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： vKLG9ovlY  
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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。 -;.fU44O[#  
余下的脚本计算与屈光度有关的所有参数。 BeCr){,3  
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分析 QncS&  
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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。 d-&dA_?  
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脚本代码  0d)n}fm  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. Du4?n8 o  
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Dim entity As T_ENTITY u-cC}DP  
Dim op As T_OPERATION r2`?Ta  
Dim mat As T_MODELMATERIAL RS=7W._W  
Dim A As Double uB!P>v6  
Dim pupilDiam As Double F&Z>B};  
Dim eID As Long lsxii-#O  
Dim parID As Long [qo*,CRz  
Dim count As Integer 8[XNFFUZs  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double a[#BlH  
Dim tlens As Double, nlens As Double 2)H|/  
Dim curv As Double, conic As Double ^U1+D^AJ  
Dim ok As Long bJvRQrj*3  
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Sub Main xk<0QYv   
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    '用户输入对话框 DvKMb-*S  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ba.OjK@  
        TextBox 220,21,40,21,.TextBox1 'default: 0 o W [-?  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 *V+fRN4 W  
        OKButton 40,91,90,21 }zLE*b,  
        CancelButton 190,91,90,21 +<#-52br\  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 v7RDoO]I  
        TextBox 220,49,40,21,.TextBox2 'default: 4 zoXF"Nz  
    End Dialog V!4E(sX  
    Dim dlg As UserDialog ijT^gsLL  
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    ok = Dialog (dlg) 8A=(,)`}9  
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    If ok=0 Then    'cancel button was pressed JaTW/~ TU  
        Print "Execution cancelled." DtX{0p<T3  
        End ~Y$1OA8  
    End If Q0A1N[  
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    'Assign accommodation and pupil diameter & use defaults if field left empty &'j77tqOk  
    If dlg.TextBox1 = "" Then <aS1bQgaU  
        A = 0           'Default accommodation A#{*A  
    Else -A~<IyPt  
        A = CDbl(dlg.TextBox1) -
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    End If gqamGLK  
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    If dlg.TextBox2 = "" Then 9w|q':<  
        pupilDiam = 4   'Default pupil diameter O\z%6:'M  
    Else SJmri]4K  
        pupilDiam = CDbl(dlg.TextBox2) A1@a:P=  
    End If 4O'ho0w7  
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    Print " " UbXz`i  
    Print "Accommodation = " & A & " Diopters"  G%{jU'2  
    Print "Pupil Diameter = " & pupilDiam & " mm" bjZ?WZr  
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    ' Calculate new parameters with accommodation ~5zhK:7c  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness QS_xOQ '  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens j@f(cRAf#  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens N~_gT Jr~P  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens %\u>%s
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens YrX{,YtiX  
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    tlens = 3.767 + 0.04*A                  'Lens thickness iW)Ou?aS  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction "7d_$.Z  
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    'Adjust parameters to account for accommodation ]v@,>!Wn  
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    '************************************************************************* NoT oLt\  
    'Aqueous thickness (Position of Lens) #N:o)I  
    '************************************************************************* nN:i{t4f  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) W0Vjs|/  
    GetCustomElement eID, entity U-d&q>_@A  
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    parID = FindFullName( "Geometry.Arizona Eye" ) L!5HE])<)  
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    ' Delete any shift(s) in z (plOV
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    count = 0 BR*U9K|W  
    While GetOperationCount(eID)>count @r<w|x}  
        GetOperation eID, count, op ;NEHbLH#F  
        If op.Type="ShiftZ" Then O-RiDYej  
            DeleteOperation eID,count '?nhpT^  
            count=count-1 ;C3](  
        End If QCMF_;aNI  
        count=count+1 W NCdk$  
    Wend >dO^pDSs  
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    'Set new shift in b^1!_1c  
    op.Type = "ShiftZ" ?V+=uTCq  
    op.val1 = taq aO{k-44y  
    op.parent = parID zc_3\N  
    AddOperation eID, op gBN;j  
    Print "Set aqueous humor thickness = " & taq-0.55 vU_#(jZ  
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    '************************************************************************* iqpy5  
    'Radius and conic constant of anterior lens hhpH)Bi=  
    '************************************************************************* 4r %NtXAa  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) z`W$/tw"  
    GetConic eID, entity, curv, conic z;LntQZp-  
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    SetConic eID, entity, 1/Rant, CCant @jfd.? RK!  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 9 HuE'(wQ  
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    '************************************************************************* S;= D/)[mr  
    'Radius and conic constant of posterior lens tkA '_dcIC  
    '************************************************************************* VrHFM(RNe  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) +
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    GetConic eID, entity, curv, conic {ES3nCL(8  
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    SetConic eID, entity, 1/Rpost, CCpost FXIQS'  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost UGIyNMY  
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    '************************************************************************* yzYPT}t  
    'Lens thickness (Position of posterior lens surface) &N,c:dNe  
    '************************************************************************* KV Mm<]Z  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) t>^A
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    ' Delete any z-shift(s) +<I>]J2  
    count = 0 `6'fX[j5  
    While GetOperationCount(eID)>count |]V0sgpoZ  
        GetOperation eID, count, op +~HL"Vv  
        If op.Type="ShiftZ" Then 7 'N&jI   
            DeleteOperation eID,count zXB.)4T  
            count=count-1
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        End If TRa|}JaI"  
        count=count+1 ,?728pfw  
    Wend hH>t  
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    'Set new z-shift !fY'^Ya?  
    op.Type = "ShiftZ" 0} uH  
    op.val1 = tlens #49,7OBU  
    op.parent = parID f$R]m2  
    AddOperation eID, op sdrALl;w|  
    Print "Set lens thickness = " & tlens YajUdpJi  
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    '************************************************************************* d(<[$3.  
    'Lens index of refraction [+UF]m%W  
    '************************************************************************* Ft'?43J  
    eID = FindMaterial( "Lens" ) *1|&uE&_R  
    GetModelMaterial eID, mat =5is
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    mat.Nd = nlens 4vF1  
    SetModelMaterial eID, mat i.Yz)Bw  
    Print "Set lens index of refraction = " & nlens NLRgL'+F  
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    '************************************************************************* dL!PpLR$2  
    'Pupil diameter #A+ dj| b  
    '************************************************************************* 26?yEd6^Z  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) N2WQrTA:S+  
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    'Adjust pupil diameter (trimming volume inner hole) A@4sb W_  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Yv\>\?865  
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    ' Adjust pupil location to just in front of the lens Xgou7x<  
    parID = FindFullName( "Geometry.Arizona Eye" ) \b6H4aQii  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) c"~+Y2]tL  
    count = 0 A&XI1. j6  
    While GetOperationCount(eID)>count MF69n,(o  
        GetOperation eID, count, op {oOzXc
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        If op.Type="ShiftZ" Then 5o-WA1  
            DeleteOperation eID,count 8`M) r'5  
            count=count-1 0
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        End If Gf*|f"O  
        count=count+1 jOV,q%)^,:  
    Wend ;W 16Hr Z  
    op.Type = "ShiftZ" k/srT<  
    op.val1 = taq-0.01 YBF|0A{[Y  
    op.parent = parID [TRHcz n  
    AddOperation eID, op ai0am  
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    Print "Set pupil diameter = " & pupilDiam f-$%Ck$%,  
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    'Update AZ Eye subassembly Description Q6%dM'fR  
    eID = FindFullName( "Geometry.Arizona Eye" ) !X5n'1&  
    GetEntity eID, entity I8M^]+c  
    entity.Description = "Accommodation = " & A & "D" },#@q_E  
    SetEntity eID, entity \+3amkBe  
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    Update Y~,ZBl,  
    Print "DONE!" ?P
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End Sub x:dI:G  
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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： Ry_"sow4  

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Accommodation = 4 Diopters t:$^iUrx  
Pupil Diameter = 4 mm B\*"rSP\  
Set aqueous humor thickness = 2.81 xWR<>Og.  
Set anterior lens radius = 10.4 and conic constant = -2.375869 9IfeaoZZ4q  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 T*pcS'?'  
Set lens thickness = 3.927 \+,%RN.  
Set lens index of refraction = 1.42672 T'8d|$X  
Set pupil diameter = 4 Ga,+  
DONE! V\|V1c  
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