[技术]Arizona眼睛模型 [复制链接]

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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。 wn84?$BGd  
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模型 9d\N[[Vu]R  
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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]e-P%  
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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. 2"M
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光源 AM/lbMr  
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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。 i./Y w
 
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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。 .tp=T  
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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。 cYD1~JX.  
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视网膜的散射 q]l\`/R%u  
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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。 rgn|24x  
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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。 my=~"bw4  
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脚本 yh$ ~*UV  
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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： Xr)g  
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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。 Y?e3Bx7*b  
余下的脚本计算与屈光度有关的所有参数。 cWc$yE'  
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分析 rZ 6@b  
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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。 m9cj7  
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脚本代码 6yi/&#YM  

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Option Explicit     'Remove this to enable non-dimensioned variables to be used. @US '{hO1p  
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Dim entity As T_ENTITY B1HQz@^  
Dim op As T_OPERATION )/ n29]  
Dim mat As T_MODELMATERIAL 739l%u }<  
Dim A As Double =b|)Wnt2f  
Dim pupilDiam As Double >02i8:Tp5K  
Dim eID As Long [lrmuf  
Dim parID As Long YU*46 hA1B  
Dim count As Integer _4!7 zW^  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ( / G)"]  
Dim tlens As Double, nlens As Double =+k&&vOAn  
Dim curv As Double, conic As Double #{?m  
Dim ok As Long E)RI!0Ra  
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Sub Main 
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    '用户输入对话框 ?Of{c,2 .  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 zl,bMtQ  
        TextBox 220,21,40,21,.TextBox1 'default: 0 |ORmS&7  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 0 [*nAo  
        OKButton 40,91,90,21 {8ld:ZP  
        CancelButton 190,91,90,21 {Nzmb|&  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 EgkZ$ah  
        TextBox 220,49,40,21,.TextBox2 'default: 4 zS,%msT^A  
    End Dialog 'JJ1#kKa  
    Dim dlg As UserDialog %kaTQ"PB  
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    ok = Dialog (dlg) M^0w/  
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    If ok=0 Then    'cancel button was pressed K[`4vsE  
        Print "Execution cancelled." l;.[W|  
        End pqRO[XEp2  
    End If ]JGKL5~p  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ,S7~=S  
    If dlg.TextBox1 = "" Then >MBn2(\B;  
        A = 0           'Default accommodation P6.)P|n7=  
    Else 6kgCS{MZ  
        A = CDbl(dlg.TextBox1) v3iDh8.__  
    End If ,APGPE}I[  
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    If dlg.TextBox2 = "" Then )&g2D@+{  
        pupilDiam = 4   'Default pupil diameter 3ZT/>a>@  
    Else tF{{cd  
        pupilDiam = CDbl(dlg.TextBox2) R.^Bxi-UG:  
    End If a3DoLq"/  
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    Print " " R|cFpRe  
    Print "Accommodation = " & A & " Diopters" Y2ah zB  
    Print "Pupil Diameter = " & pupilDiam & " mm" ?];~N5<'  
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    ' Calculate new parameters with accommodation m bB\~n  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness +dPE!:  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens \&l*e  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens RBHqLg(  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens (STWAwK-  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens z[<pi:  
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    tlens = 3.767 + 0.04*A                  'Lens thickness Wr}a\}R  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction x1 R!  
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    'Adjust parameters to account for accommodation D7n&9Z  
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    '************************************************************************* #o}{cXX#  
    'Aqueous thickness (Position of Lens) PN)TX~}  
    '************************************************************************* xu\/]f)  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 7J)Hwl  
    GetCustomElement eID, entity ~-o^eI4_  
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    parID = FindFullName( "Geometry.Arizona Eye" ) d}^:E  
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    ' Delete any shift(s) in z qH}62DP3  
    count = 0 r4z}yt+  
    While GetOperationCount(eID)>count ix_$Ok  
        GetOperation eID, count, op 2EI m  
        If op.Type="ShiftZ" Then ` wsMybe#  
            DeleteOperation eID,count &_Xv:?  
            count=count-1 'f$?/5@@  
        End If - KoA[
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        count=count+1 G~mB=]  
    Wend } cH"lppX  
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    'Set new shift in ZLFdnC@  
    op.Type = "ShiftZ" ybuSqFy`$  
    op.val1 = taq mc[_
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    op.parent = parID ^FpiQF  
    AddOperation eID, op 'yAoZ P\|  
    Print "Set aqueous humor thickness = " & taq-0.55 ;7hX0AK  
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    '************************************************************************* L-oPb)  
    'Radius and conic constant of anterior lens C#u)$Ds  
    '************************************************************************* SBB bniK-  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Fw8X$SE"  
    GetConic eID, entity, curv, conic ef1N#z%gt  
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    SetConic eID, entity, 1/Rant, CCant dpOL1rrE  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ZkVvL4yIK  
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    '************************************************************************* V,*0<7h  
    'Radius and conic constant of posterior lens :_[cT,3  
    '************************************************************************* $>*/']>  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ^`PSlT3<F  
    GetConic eID, entity, curv, conic }5c'ui!3H  
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    SetConic eID, entity, 1/Rpost, CCpost 8"I5v(TV  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ;@;
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    '************************************************************************* -*{(#k$  
    'Lens thickness (Position of posterior lens surface) @'| 6lG  
    '************************************************************************* 68G] a N3  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ;>x1)|n5  
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    ' Delete any z-shift(s) A.cZa  
    count = 0 QBT-
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    While GetOperationCount(eID)>count ?+JxQlVDt-  
        GetOperation eID, count, op w
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        If op.Type="ShiftZ" Then !/q&0a  
            DeleteOperation eID,count KV&_^xSoh|  
            count=count-1 [q|Q]O0  
        End If g7q]Vj  
        count=count+1 |\L,r}1N  
    Wend q8yJW-GA   
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    'Set new z-shift Env}gCX  
    op.Type = "ShiftZ" #i#.tc  
    op.val1 = tlens -t
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    op.parent = parID ra#)*fG,~  
    AddOperation eID, op 3<Y;mA=hw  
    Print "Set lens thickness = " & tlens lNnbd?D8  
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    '************************************************************************* [tw<TV"\  
    'Lens index of refraction ENF@6]  
    '************************************************************************* 9%'HB\A  
    eID = FindMaterial( "Lens" ) f$*9J  
    GetModelMaterial eID, mat k |aOUW  
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    mat.Nd = nlens 8Nq Iz  
    SetModelMaterial eID, mat Am^O{`r41  
    Print "Set lens index of refraction = " & nlens H;8]GE2n  
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    '************************************************************************* G6ES]  
    'Pupil diameter cO?
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    '************************************************************************* hp%Pg &  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ~G^doj3|+  
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    'Adjust pupil diameter (trimming volume inner hole) e:D9;`C  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" *LQY6=H  
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    ' Adjust pupil location to just in front of the lens ~(E8~)f)  
    parID = FindFullName( "Geometry.Arizona Eye" ) o5A_j?t  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) lNPbU ~k  
    count = 0 9&FV=}MO  
    While GetOperationCount(eID)>count I*ni)Px  
        GetOperation eID, count, op Wb(0Szk;  
        If op.Type="ShiftZ" Then {Ag}P0%'  
            DeleteOperation eID,count ~ab_+%  
            count=count-1 e-av@a3
  
        End If SJr:  
        count=count+1 -H;y_^2  
    Wend _NW OSt  
    op.Type = "ShiftZ" f__WnW5h  
    op.val1 = taq-0.01 eBKIdR%k  
    op.parent = parID *N+aZV}`Z  
    AddOperation eID, op S.4YC>E  
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    Print "Set pupil diameter = " & pupilDiam W,J,h6{F  
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    'Update AZ Eye subassembly Description (6^k;j  
    eID = FindFullName( "Geometry.Arizona Eye" ) Vb#@o)z  
    GetEntity eID, entity 3k0%H]wt  
    entity.Description = "Accommodation = " & A & "D" $yK!Q)e:  
    SetEntity eID, entity d9( Sj?  
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    Update @zq{#7%z  
    Print "DONE!" &4
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End Sub Br!&Y9  
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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： zPc;[uHT  
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Accommodation = 4 Diopters Z.(x|Q9  
Pupil Diameter = 4 mm _x{x#d;L3  
Set aqueous humor thickness = 2.81 jG :R\D}0  
Set anterior lens radius = 10.4 and conic constant = -2.375869 a~"X.xT\R  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 ![tI(TPq  
Set lens thickness = 3.927 cyE2=  
Set lens index of refraction = 1.42672 %%[TM(z  
Set pupil diameter = 4 g7F Z -  
DONE! \LXC269