[分享]Arizona眼睛模型 [复制链接]

简介 tSux5yV  
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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。 :
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模型 nW^h +  
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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。 B=;kC#Emtf  
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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~~4eia)  
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光源 OF={k[  
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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。 P 4t@BwU$  
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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。 %gs?~Xl)]  
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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。 1x=x,lcL  
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视网膜的散射 ^"D^D`$@  
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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。 _k26(rdI@-  
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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。 qEXN}P
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脚本 :H3/+/x  
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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： >W8"Ar  
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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。 ohqThl  
余下的脚本计算与屈光度有关的所有参数。 aQ$sn<-l  
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分析 R'`'q1=R  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ]b;m~|9  
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脚本代码 \Z3K ~  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. *l{epum;  
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Dim entity As T_ENTITY / @"{u0  
Dim op As T_OPERATION YLQ0UeDN'  
Dim mat As T_MODELMATERIAL C{pOGc@  
Dim A As Double cZ?$_;=  
Dim pupilDiam As Double  {
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Dim eID As Long PIa!NPy  
Dim parID As Long V=*^C+6s  
Dim count As Integer M Zz21H  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double =xIZJ8e  
Dim tlens As Double, nlens As Double Wj^e)2%  
Dim curv As Double, conic As Double GnW MI1$  
Dim ok As Long -grf7w^  
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Sub Main /Yp#`}Ii  
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    '用户输入对话框 =/46;844T  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 =n"kgn  
        TextBox 220,21,40,21,.TextBox1 'default: 0 \ m~?yq8H  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 NT*r7_e  
        OKButton 40,91,90,21 ]<f(@]R/d  
        CancelButton 190,91,90,21 6 Ln~b<I  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 x+Xd7N1  
        TextBox 220,49,40,21,.TextBox2 'default: 4 B F<u3p??  
    End Dialog D?1fY!C:r  
    Dim dlg As UserDialog I_v}}h{  
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    ok = Dialog (dlg) n_km]~  
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    If ok=0 Then    'cancel button was pressed zVw5(Tc  
        Print "Execution cancelled." ;C$+8%P4  
        End u3+B/ 5x  
    End If Pn">fWRCx  
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    'Assign accommodation and pupil diameter & use defaults if field left empty &}k7iaO  
    If dlg.TextBox1 = "" Then 4G(7V:  
        A = 0           'Default accommodation g) u%?T  
    Else )/::i O&$:  
        A = CDbl(dlg.TextBox1) +_i{4Iz~p  
    End If ,<tJ`,0X  
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    If dlg.TextBox2 = "" Then ^-~JkW'z  
        pupilDiam = 4   'Default pupil diameter UrvUt$WO  
    Else @Uez2?  
        pupilDiam = CDbl(dlg.TextBox2) JyMk @Y  
    End If mg'q-G`\<  
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    Print " " Q p>b  
    Print "Accommodation = " & A & " Diopters" ,\\ba_*z  
    Print "Pupil Diameter = " & pupilDiam & " mm" aP  
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    ' Calculate new parameters with accommodation MMFwT(l<1  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness \QK@wgu  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 8~o']B;lJ  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens &*<27-x  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens F$?Ab\#B  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens TBBnsj6e  
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    tlens = 3.767 + 0.04*A                  'Lens thickness 0!|d .jZI  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction XX~vg>3_  
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    'Adjust parameters to account for accommodation /YvXyi>^"%  
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    '************************************************************************* :G1ddb&0+  
    'Aqueous thickness (Position of Lens) (G"'Fb6d  
    '************************************************************************* 9b+jT{Tg  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) =#G 2}8mQD  
    GetCustomElement eID, entity r.H`3m.0q  
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    parID = FindFullName( "Geometry.Arizona Eye" ) j~qm$'H  

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    ' Delete any shift(s) in z wGAr
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    count = 0 |RiJ>/MK\  
    While GetOperationCount(eID)>count QO'Hyf t  
        GetOperation eID, count, op i?6&4  
        If op.Type="ShiftZ" Then uDDa>Ka#+  
            DeleteOperation eID,count i<Vc~!pT  
            count=count-1 +FTc/r  
        End If 9*)&hhBs,  
        count=count+1 6Xvpk1
  
    Wend _ >OP  
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    'Set new shift in \HeJc:^  
    op.Type = "ShiftZ" y*i&p4Y*  
    op.val1 = taq Pp8S\%z~h  
    op.parent = parID +vh|m5"7I7  
    AddOperation eID, op S>yiD`v  
    Print "Set aqueous humor thickness = " & taq-0.55 n$/|r  
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    '************************************************************************* v"bWVc~H  
    'Radius and conic constant of anterior lens 7*5B  
    '************************************************************************* /Y7^!3uM  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) /s\ mV  
    GetConic eID, entity, curv, conic +K4XMf  
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    SetConic eID, entity, 1/Rant, CCant hw DxGiU  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant |`T(:ZKXZ2  
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    '************************************************************************* ,MY7h8V/  
    'Radius and conic constant of posterior lens H%wB8Y ]  
    '************************************************************************* Cy~IB [  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) @?,x3\N-  
    GetConic eID, entity, curv, conic  =z.j{%  
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    SetConic eID, entity, 1/Rpost, CCpost pHeG{<^  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost E'QAsU8pP  
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    '************************************************************************* KYFKH+d>m  
    'Lens thickness (Position of posterior lens surface) .hT>a<  
    '************************************************************************* 0j$\k|xFXZ  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 1b5Z^a<u  
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    ' Delete any z-shift(s) /;`H )  
    count = 0 ~MG6evm &  
    While GetOperationCount(eID)>count _{*}
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        GetOperation eID, count, op h3MdQlJ&  
        If op.Type="ShiftZ" Then TDh)}Ms  
            DeleteOperation eID,count "Lp.*o  
            count=count-1 'n &p5%  
        End If t>bzo6cj  
        count=count+1 "-4|HA  
    Wend V}E['fzBFV  
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    'Set new z-shift P3oYk_oW  
    op.Type = "ShiftZ" PQHztS"  
    op.val1 = tlens GkAd"<B  
    op.parent = parID c1H.v^Y5  
    AddOperation eID, op o|xf2k  
    Print "Set lens thickness = " & tlens k[Em~>m  
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    '************************************************************************* K9<8FSn  
    'Lens index of refraction oC&}lp)q
 
    '************************************************************************* JYdb^j2c  
    eID = FindMaterial( "Lens" ) _J,**AZ~z  
    GetModelMaterial eID, mat 49qa  
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    mat.Nd = nlens dwA"QVp{  
    SetModelMaterial eID, mat zEQ]5>mG  
    Print "Set lens index of refraction = " & nlens mF6-f#t>H+  
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    '************************************************************************* ql?w6qFs]  
    'Pupil diameter RoqkT|#$  
    '************************************************************************* ']}-;m\  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) !?,, ZD  
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    'Adjust pupil diameter (trimming volume inner hole) 4H

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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Qf:e;1F!  
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    ' Adjust pupil location to just in front of the lens &9e  
    parID = FindFullName( "Geometry.Arizona Eye" ) P]+B}))  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ~kc#
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    count = 0 !'$*Z(  
    While GetOperationCount(eID)>count =ejcP&-V/  
        GetOperation eID, count, op H I9/  
        If op.Type="ShiftZ" Then cW3'057  
            DeleteOperation eID,count XpAJP++  
            count=count-1 |!oC7!+0^  
        End If l$u52e!7  
        count=count+1 MW
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    Wend B>u`%Ry&  
    op.Type = "ShiftZ" -@AhJY.  
    op.val1 = taq-0.01 3W'fEh5  
    op.parent = parID r/h\>s+N  
    AddOperation eID, op >MYxj}I4{z  
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    Print "Set pupil diameter = " & pupilDiam J.iz%8  
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    'Update AZ Eye subassembly Description dv. 77q  
    eID = FindFullName( "Geometry.Arizona Eye" ) =eA|gt  
    GetEntity eID, entity `0upm%A  
    entity.Description = "Accommodation = " & A & "D" b^R:q7ea  
    SetEntity eID, entity SFg4}*"C/  
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    Update aT^ $'_ G  
    Print "DONE!" ET[5`z  
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End Sub /`cy4<  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： P$'PB*5d|  
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Accommodation = 4 Diopters g9C-!X-<T  
Pupil Diameter = 4 mm T4x%3-4;  
Set aqueous humor thickness = 2.81 t__f=QB/  
Set anterior lens radius = 10.4 and conic constant = -2.375869 kQI'kL8>  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 w&@tP^`  
Set lens thickness = 3.927 ,DEq"VW_  
Set lens index of refraction = 1.42672 0d[O/Q`  
Set pupil diameter = 4 LR&MhG7  
DONE! :r{-:   
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