[技术]Arizona眼睛模型 [复制链接]

简介 ( FRf.mv{  
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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。 {m?x},  
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模型 )qIK7;  
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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。 pf_ /jR  
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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. ao!r6:&v$e  
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光源 SJ-Sac58r  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 *Y ZLQT  
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除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 5PPpX=\  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 7w*&Yg]  
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视网膜的散射 8rYK~Sz  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 ?r<F\rBT7*  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 C.-a:oQ[  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： GB3B4)cX4Y  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 sBnPS[Oo  
余下的脚本计算与屈光度有关的所有参数。 8B/9{8  
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分析 s_!Z+D$K  
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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。 {6sfa?1j  
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脚本代码 ]s@8I2_  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 9K<a}QJP  
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Dim entity As T_ENTITY ':]a.yA\1  
Dim op As T_OPERATION 1,'^BgI,  
Dim mat As T_MODELMATERIAL qhtAtP>i"  
Dim A As Double ,r;d{  
Dim pupilDiam As Double u$8MVP  
Dim eID As Long wf%Ep#^6}  
Dim parID As Long f*}E\,V"&  
Dim count As Integer wlg#c6#q  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double @0,dyg<$>  
Dim tlens As Double, nlens As Double cV,Dl`1r  
Dim curv As Double, conic As Double q)+n2FM  
Dim ok As Long 8{%9%{  
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Sub Main mp3_n:R?  
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    '用户输入对话框 J6D$ i+  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 }F6b ]  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Zb;$
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        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 e~]e9-L>I  
        OKButton 40,91,90,21 g8A{aHb1}  
        CancelButton 190,91,90,21 >[4|6k|\x  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 l>Ja[`X@  
        TextBox 220,49,40,21,.TextBox2 'default: 4 iGVb.=)  
    End Dialog bCUh^#]x  
    Dim dlg As UserDialog $ywh%OEH  
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    ok = Dialog (dlg) t`t:qko  
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    If ok=0 Then    'cancel button was pressed ![ID0}MjJ  
        Print "Execution cancelled." }IkEyJsk  
        End {0WIDD  
    End If vqz#V=J{  
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    'Assign accommodation and pupil diameter & use defaults if field left empty l!V| T?  
    If dlg.TextBox1 = "" Then Z;SG<  
        A = 0           'Default accommodation (A fbS=[  
    Else !nBm}E7d  
        A = CDbl(dlg.TextBox1) xh^ZI6L<  
    End If }.V0SM6  
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    If dlg.TextBox2 = "" Then o\;"|O}  
        pupilDiam = 4   'Default pupil diameter nk$V{(FJ  
    Else x][9ptrh  
        pupilDiam = CDbl(dlg.TextBox2) c&?a,fpb  
    End If f<4q]HCa  
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    Print " " AYu'ptDNr  
    Print "Accommodation = " & A & " Diopters" (g2r\hI  
    Print "Pupil Diameter = " & pupilDiam & " mm" u+'@>%7  
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    ' Calculate new parameters with accommodation SY>,kwHO  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ^'53]b:  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 1S]gD&V  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens \{=`F`oB=  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens UEQ'D9  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens S]%U]
 
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    tlens = 3.767 + 0.04*A                  'Lens thickness LO}:Ub  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction .Jat^iFj0  
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    'Adjust parameters to account for accommodation
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    '************************************************************************* U[e8K  
    'Aqueous thickness (Position of Lens) vV\F^  
    '************************************************************************* LVFsd6:h  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) dIfs8%kl  
    GetCustomElement eID, entity H^PqYLjN  
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    parID = FindFullName( "Geometry.Arizona Eye" ) -=t3O#  
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    ' Delete any shift(s) in z [T[9*6Kt  
    count = 0 w]Ko/;;^2  
    While GetOperationCount(eID)>count Y^ZBA\D2,k  
        GetOperation eID, count, op  2HK  
        If op.Type="ShiftZ" Then uJ/?+5TU  
            DeleteOperation eID,count +`s&i%{1>  
            count=count-1 @+\S!o3m  
        End If $,QpSK`9i  
        count=count+1 "X{aS}  
    Wend NzeI/f3K5  
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    'Set new shift in n@07$lY@;  
    op.Type = "ShiftZ" o&XMgY~  
    op.val1 = taq |N=@E,33  
    op.parent = parID A?;8%00  
    AddOperation eID, op '=Kof1  
    Print "Set aqueous humor thickness = " & taq-0.55 Il^\3T+  
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    '************************************************************************* 'Elj"Iiu  
    'Radius and conic constant of anterior lens h\u0{!@}  
    '************************************************************************* R<lNk<  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 6mF{ImbRbS  
    GetConic eID, entity, curv, conic Id.Z[owC`Y  
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    SetConic eID, entity, 1/Rant, CCant e@,u`{C[  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant -wfRR>)d  
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    '************************************************************************* ^QXw[th!d  
    'Radius and conic constant of posterior lens a:-)+sgHw  
    '************************************************************************* HL(U~Q6JQ  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) s7.p$r  
    GetConic eID, entity, curv, conic 2%{YYT   
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    SetConic eID, entity, 1/Rpost, CCpost s?@)a,C%k  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost iO9nvM<  
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    '************************************************************************* FV^4  
    'Lens thickness (Position of posterior lens surface) =~\]3g  
    '************************************************************************* %7NsBR!y  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) }#ep}h  
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    ' Delete any z-shift(s) W8G9rB
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    count = 0 4{*tn"y  
    While GetOperationCount(eID)>count SvX=isu!.  
        GetOperation eID, count, op &
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        If op.Type="ShiftZ" Then 0~Iu7mPY  
            DeleteOperation eID,count p- "Z'$A`  
            count=count-1 q?imE~&U  
        End If jNe(w<',P  
        count=count+1 GJIWG&C03  
    Wend "xDx/d8B  
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    'Set new z-shift GP[6nw_'^  
    op.Type = "ShiftZ" G%7 4v|cd  
    op.val1 = tlens c?!YFm  
    op.parent = parID ] Wx>)LT  
    AddOperation eID, op 6Iv(  
    Print "Set lens thickness = " & tlens =mHkXHE~:  
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    '************************************************************************* poXLy/K  
    'Lens index of refraction :H!(?(Pie  
    '************************************************************************* tjZ\h=  
    eID = FindMaterial( "Lens" ) HDF!`  
    GetModelMaterial eID, mat  Y8)E]D  
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    mat.Nd = nlens J$#h(D%  
    SetModelMaterial eID, mat y:[BP4H?y  
    Print "Set lens index of refraction = " & nlens ex` xkZ+  
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    '************************************************************************* ioC@n8_[G  
    'Pupil diameter <i_> y~v`  
    '************************************************************************* u\{qH!?t  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) $nB-ADRu@  
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    'Adjust pupil diameter (trimming volume inner hole) .O5LI35,  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 1Yc%0L(  
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    ' Adjust pupil location to just in front of the lens kAZC"qM%i  
    parID = FindFullName( "Geometry.Arizona Eye" ) $uEJn&n7}  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Z69+yOJI  
    count = 0 pOqGAD{D$  
    While GetOperationCount(eID)>count Yv)Bj  
        GetOperation eID, count, op )!'n&UxPo$  
        If op.Type="ShiftZ" Then AIuMX4nb  
            DeleteOperation eID,count Y
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            count=count-1 nK+lE0  
        End If R<f#r03@|  
        count=count+1 9o-!ecx}  
    Wend B0f_kH
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    op.Type = "ShiftZ" 9pWi.J  
    op.val1 = taq-0.01 UdT&cG  
    op.parent = parID `S"W8_m  
    AddOperation eID, op jja{*PZ6H  
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    Print "Set pupil diameter = " & pupilDiam SHMl%mw  
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    'Update AZ Eye subassembly Description DdBxqkh  
    eID = FindFullName( "Geometry.Arizona Eye" ) mfXD1]<.  
    GetEntity eID, entity ~O \}/I28  
    entity.Description = "Accommodation = " & A & "D" (# JMB)  
    SetEntity eID, entity yh S#&)O  
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    Update }o-|8P:Y  
    Print "DONE!" 2 9q?$V(  
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End Sub @ru<4`h  
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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： 53B.2 4Tm  
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Accommodation = 4 Diopters 2=>*O  
Pupil Diameter = 4 mm UM<@t%|>  
Set aqueous humor thickness = 2.81 +H7y/#e+3  
Set anterior lens radius = 10.4 and conic constant = -2.375869 E]NY (1  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 {5>3;.  
Set lens thickness = 3.927 Ba<ngG !  
Set lens index of refraction = 1.42672 p~h4\.*`  
Set pupil diameter = 4 [M4xZHd#o  
DONE! &]w#z=5SXi