[分享]Arizona眼睛模型 [复制链接]

简介 hcM9Sx"!  

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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。 Q5A
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模型 9z`72(  
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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。  > H&v  
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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. 5gkQ6&m  

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光源 dc0&*/`:  
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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。 abv*X1  
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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。 g W_E  
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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。 !p76I=H%  
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视网膜的散射 T]/5aA4  
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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。 =M}tet }  
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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。 lr[T+nQ  
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脚本 RNQq"c\  
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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： EZzR"W/  
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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。 +FAxqCkA  
余下的脚本计算与屈光度有关的所有参数。 D?UURURf  
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分析 {$5g29  
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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。 ,0ilNi>  
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脚本代码 Zy.A9Bh~  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. "5z@A/Z/  
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Dim entity As T_ENTITY $06('
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Dim op As T_OPERATION =HJ7tele  
Dim mat As T_MODELMATERIAL K:kb&W  
Dim A As Double @'5*jXd  
Dim pupilDiam As Double p~Cz6n  
Dim eID As Long xB[W8gQ6fa  
Dim parID As Long zGNW5S9G  
Dim count As Integer mP/#hwzB&q  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double PIXqd,  
Dim tlens As Double, nlens As Double ^*+M9e9Z  
Dim curv As Double, conic As Double SSTn|  
Dim ok As Long ?B$L'i[l  
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Sub Main l'
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    '用户输入对话框 b:r8r}49  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Xit@.:a;  
        TextBox 220,21,40,21,.TextBox1 'default: 0 S:Jg#1rww-  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 3 {hUp81>  
        OKButton 40,91,90,21 Z!Z{Gm3  
        CancelButton 190,91,90,21 aMxj{*v7  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 $G6kS@A  
        TextBox 220,49,40,21,.TextBox2 'default: 4 k@s<*C  
    End Dialog >mpNn  
    Dim dlg As UserDialog Mk=*2=d  
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    ok = Dialog (dlg) 
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    If ok=0 Then    'cancel button was pressed w^^l,  
        Print "Execution cancelled." 6uKth mr  
        End \x:U`T  
    End If Iw`|,-|  
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    'Assign accommodation and pupil diameter & use defaults if field left empty >R_m@$`  
    If dlg.TextBox1 = "" Then 8B-mZFXpK  
        A = 0           'Default accommodation 1Y;.fZE  
    Else -!mtL
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        A = CDbl(dlg.TextBox1) <P ?gP1_zi  
    End If 2xiE#l-V2  
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    If dlg.TextBox2 = "" Then `QRXQ c  
        pupilDiam = 4   'Default pupil diameter wtfH3v  
    Else 9z{g3m70@  
        pupilDiam = CDbl(dlg.TextBox2) X8}\m%gCU  
    End If z C$F@  
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    Print " " @8w5Oudvx  
    Print "Accommodation = " & A & " Diopters" V2AsZc0U(  
    Print "Pupil Diameter = " & pupilDiam & " mm" __s'/6u  
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    ' Calculate new parameters with accommodation J>G'H)  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness <HTz  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens aIQC[ry  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens /*BK6hc  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Y,yU460T8  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 0H.bRk/P+  
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    tlens = 3.767 + 0.04*A                  'Lens thickness WA1yA*S  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction fF>hca>  
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    'Adjust parameters to account for accommodation 6vxRam6[??  
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    '************************************************************************* \6.dGKK  
    'Aqueous thickness (Position of Lens) [`E_/95  
    '************************************************************************* l-20X{$m:  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) -^t.eZ*|  
    GetCustomElement eID, entity GUM-|[~  
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    parID = FindFullName( "Geometry.Arizona Eye" ) \L$]2"/v-  
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    ' Delete any shift(s) in z 3D5adI<aq"  
    count = 0 N%q{CYF6  
    While GetOperationCount(eID)>count :SO4@JT{W  
        GetOperation eID, count, op xC=$ym]  
        If op.Type="ShiftZ" Then zVe,HKF/  
            DeleteOperation eID,count Oml3=TV  
            count=count-1 nGK=Nf.5  
        End If x
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        count=count+1 oRcP4k;d=  
    Wend +XX5;;IC  
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    'Set new shift in *%_M?^  
    op.Type = "ShiftZ" <nV3`L&]  
    op.val1 = taq nehk8+eV_  
    op.parent = parID X|g5tnsj`  
    AddOperation eID, op TV_a(#S  
    Print "Set aqueous humor thickness = " & taq-0.55 `:m=r
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    '************************************************************************* +!`$(  
    'Radius and conic constant of anterior lens SX =^C  
    '************************************************************************* ?}W#j  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) \k6OP  
    GetConic eID, entity, curv, conic 2v4&'C  
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    SetConic eID, entity, 1/Rant, CCant L"?4}U:  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant dvY3=~'  
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    '************************************************************************* ,m7Z w_.  
    'Radius and conic constant of posterior lens $(OL#>9Ly  
    '************************************************************************* %wu,ce]*  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) c$u#U~~  
    GetConic eID, entity, curv, conic }095U(@  
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    SetConic eID, entity, 1/Rpost, CCpost i*
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost u8<Fk !  
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    '************************************************************************* j *N^.2  
    'Lens thickness (Position of posterior lens surface) M3GFKWQI,`  
    '************************************************************************* $SniQ  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ^;\6ju2  
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    ' Delete any z-shift(s)
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    count = 0 jlUT9Zp  
    While GetOperationCount(eID)>count abEdZ)$  
        GetOperation eID, count, op F:0 E- z'  
        If op.Type="ShiftZ" Then b+CvA(*  
            DeleteOperation eID,count #\z"k<{*  
            count=count-1 aKRnj!4z  
        End If pf=CP%L  
        count=count+1 /wHfc[b>  
    Wend ry* 9  
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    'Set new z-shift sP8_Y,  
    op.Type = "ShiftZ" (Fk&~/SP  
    op.val1 = tlens 5y~B/.YY  
    op.parent = parID XR#?gx.}  
    AddOperation eID, op g%4=T~  
    Print "Set lens thickness = " & tlens L'>0E(D  
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    '************************************************************************* eN<?rVZl  
    'Lens index of refraction k.H4Mf(4  
    '************************************************************************* b3-+*5L  
    eID = FindMaterial( "Lens" ) #q?:Act  
    GetModelMaterial eID, mat Az(J@  
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    mat.Nd = nlens [{+ZQd  
    SetModelMaterial eID, mat ]k.YG!$  
    Print "Set lens index of refraction = " & nlens q&wv{  

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    '************************************************************************* +j6^g*  
    'Pupil diameter *AYjMCo  
    '************************************************************************* tZD^<Q7}\  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Z2k5qs7g  
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    'Adjust pupil diameter (trimming volume inner hole) `
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" k@2@%02o9C  
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    ' Adjust pupil location to just in front of the lens Yb>A?@S  
    parID = FindFullName( "Geometry.Arizona Eye" ) };8PPR)\y  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) .[o?qCsw  
    count = 0 t~]tw  
    While GetOperationCount(eID)>count -/6Ms%O  
        GetOperation eID, count, op BOW`{=  
        If op.Type="ShiftZ" Then !f8]gTzN  
            DeleteOperation eID,count k=5v J72U  
            count=count-1 mDIN%/S'  
        End If 'jU;.vZex  
        count=count+1 |DoD.?v  
    Wend fu`|@
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    op.Type = "ShiftZ" ebB8.(k9G3  
    op.val1 = taq-0.01 TbhsOf!  
    op.parent = parID M4}zRr([.5  
    AddOperation eID, op 7C^W<SUo  
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    Print "Set pupil diameter = " & pupilDiam Kdd5ysTQ  
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    'Update AZ Eye subassembly Description ^g N?I
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    eID = FindFullName( "Geometry.Arizona Eye" ) }F)eA1  
    GetEntity eID, entity )%(H'omvl  
    entity.Description = "Accommodation = " & A & "D" k|_LF[*Z  
    SetEntity eID, entity [ST7CrwC  
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    Update \EeK<)4:  
    Print "DONE!" %;tBWyq}_  
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End Sub Y>'t)PK  
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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： U^xtS g  
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Accommodation = 4 Diopters ndB*^nT  
Pupil Diameter = 4 mm ^o6&|q  
Set aqueous humor thickness = 2.81 F%e5j9X`  
Set anterior lens radius = 10.4 and conic constant = -2.375869 n%:&N  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 zRF+D+  
Set lens thickness = 3.927 H}&4#CQ'!  
Set lens index of refraction = 1.42672 RB/;qdqR  
Set pupil diameter = 4 a6.0$'  
DONE! '9q:gFO  
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