[分享]Arizona眼睛模型 [复制链接]

简介 qc6d,z/  
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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。 Nh6!h%  
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模型 yeV|j\TJI.  
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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。 T lB+ tV>  
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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. hTQ]xN)  
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光源 M|7{ZE`Y  
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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#>mXm>  
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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。 /? Bu^KX  
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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。 s18A  
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视网膜的散射 l D]?9K29  
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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。 w-``kID  
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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。 ,v(ikPzd  
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脚本 *BQy$dfE  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： u:\DqdlU`  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 tnw6[U!rh=  
余下的脚本计算与屈光度有关的所有参数。 S!7|vb*ko  
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分析 `AhTER  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 \xOv9(  
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脚本代码 rd}|^&e!Dy  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. h) W|~y@  
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Dim entity As T_ENTITY lkgB,cflpi  
Dim op As T_OPERATION rh6m  
Dim mat As T_MODELMATERIAL h7
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Dim A As Double l~GcD  
Dim pupilDiam As Double ((]Sy,rdk  
Dim eID As Long f.Ms3))  
Dim parID As Long p}-B>v  
Dim count As Integer 5x' ^.$K >  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double n7'X.=o7  
Dim tlens As Double, nlens As Double Bfr$&?j#  
Dim curv As Double, conic As Double !o8(9F  
Dim ok As Long >66v+  
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Sub Main AJ85[~(lX  
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    '用户输入对话框 gJu
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    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 CWM_J9f  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ]08 ~"p  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 |kkg1M#  
        OKButton 40,91,90,21 xtRHb''FX  
        CancelButton 190,91,90,21 *`bAu *  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 :%"$8o*0W  
        TextBox 220,49,40,21,.TextBox2 'default: 4 c=~FXV!  
    End Dialog O4Hc"v  
    Dim dlg As UserDialog "TePO7^m  
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    ok = Dialog (dlg) .06[*S  
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    If ok=0 Then    'cancel button was pressed L2^M#G@t  
        Print "Execution cancelled." Py-}tFr  
        End Y'2 |GJc2  
    End If OqA#4h4^  
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    'Assign accommodation and pupil diameter & use defaults if field left empty H6]z98  
    If dlg.TextBox1 = "" Then nn6&`$(Q~  
        A = 0           'Default accommodation j43-YdCJ  
    Else eh}{\P  
        A = CDbl(dlg.TextBox1) X2hyxTOp  
    End If ekhx?rz  
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    If dlg.TextBox2 = "" Then tJ!s/|u(  
        pupilDiam = 4   'Default pupil diameter p1(<F_Kta  
    Else e-e*%  
        pupilDiam = CDbl(dlg.TextBox2) mA>u6Rlc  
    End If
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    Print " " '"14(BvW  
    Print "Accommodation = " & A & " Diopters" q3-V_~5^/z  
    Print "Pupil Diameter = " & pupilDiam & " mm" W=@]
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    ' Calculate new parameters with accommodation )Y@mL/_  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness %(y0,?*  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ZF6?N?t}h8  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens .YcI .  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens SN/ e41  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens S,~DA3  
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    tlens = 3.767 + 0.04*A                  'Lens thickness *P}v82C N  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction +Pm yFJH  
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    'Adjust parameters to account for accommodation *Af:^>mh  
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    '************************************************************************* WbW@V_rr  
    'Aqueous thickness (Position of Lens) Ot#O];3  
    '************************************************************************* =UW! 7OzC  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) T,eP&IN  
    GetCustomElement eID, entity Ysz&/ry  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ,Bg)p_B  
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    ' Delete any shift(s) in z =Vm"2g,aA  
    count = 0 g1s\6%g  
    While GetOperationCount(eID)>count kt*""&R  
        GetOperation eID, count, op 8V$:th('  
        If op.Type="ShiftZ" Then >uN)O-  
            DeleteOperation eID,count #A '|O\RGP  
            count=count-1 u79,+H@ep  
        End If ufekhj  
        count=count+1 "Wz#<! .r  
    Wend 8aHs I(  
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    'Set new shift in *>a+`|[1*  
    op.Type = "ShiftZ" k[p7)ec  
    op.val1 = taq E8=8OX/{Y  
    op.parent = parID dE[nPtstb  
    AddOperation eID, op 6cV -iDOH  
    Print "Set aqueous humor thickness = " & taq-0.55 ~Yw`w2  
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    '************************************************************************* ] 3@.)  
    'Radius and conic constant of anterior lens |E YJbL;1%  
    '************************************************************************* `Y~EL?
 
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) lnk`D(>W  
    GetConic eID, entity, curv, conic `N69xAiy  
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    SetConic eID, entity, 1/Rant, CCant _*SA_.0  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant [8o!X)  
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    '************************************************************************* B4 cm_YGE  
    'Radius and conic constant of posterior lens lbCTc,xT  
    '************************************************************************* !e}LB%zf  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ;%_fQNFb  
    GetConic eID, entity, curv, conic \[Dxg`;4  
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    SetConic eID, entity, 1/Rpost, CCpost JIl<4 %A  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost _djr>C=H"  
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    '************************************************************************* ecoi4f  
    'Lens thickness (Position of posterior lens surface) s:6pPJL  
    '************************************************************************* Nl3@i`;  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) /=5YHq>  
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    ' Delete any z-shift(s) &3SQVOW ~T  
    count = 0 a1
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    While GetOperationCount(eID)>count b0A*zQA_)  
        GetOperation eID, count, op ]5+db0  
        If op.Type="ShiftZ" Then J5Nz<  
            DeleteOperation eID,count i,{'}B  
            count=count-1 :
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        End If E0miX)AG  
        count=count+1 39|4)1e  
    Wend meHnT9a^  
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    'Set new z-shift "gcHcboU5$  
    op.Type = "ShiftZ"
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    op.val1 = tlens "pDwN$c  
    op.parent = parID B>hC8^.S|w  
    AddOperation eID, op )}-,4Iu%  
    Print "Set lens thickness = " & tlens h@5mVTb}i  
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    '************************************************************************* *nv%~t   
    'Lens index of refraction .#M'  
    '************************************************************************* MT8BP)C  
    eID = FindMaterial( "Lens" ) T+OQa+E@P  
    GetModelMaterial eID, mat BM(8+Wj  
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    mat.Nd = nlens lzQmD/i*  
    SetModelMaterial eID, mat BI'}  
    Print "Set lens index of refraction = " & nlens mG?g  
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    '************************************************************************* U;Iqz1S  
    'Pupil diameter +bG^SH2ke  
    '************************************************************************* YceX)  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) g:l5,j.K  
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    'Adjust pupil diameter (trimming volume inner hole) 2;Ij~~  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" @WV}VKm  
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    ' Adjust pupil location to just in front of the lens N3D{t\hg  
    parID = FindFullName( "Geometry.Arizona Eye" ) .Ulrv5wJ  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) tgy= .o]  
    count = 0 YEL,TU  
    While GetOperationCount(eID)>count xz-z" 8d  
        GetOperation eID, count, op WOW:$.VO^  
        If op.Type="ShiftZ" Then 1Na*7|  
            DeleteOperation eID,count VJK?"mX  
            count=count-1 P8hA<{UFS\  
        End If wABaNB=9;  
        count=count+1 C #A sA  
    Wend 82S?@%}#J  
    op.Type = "ShiftZ" DrfOz#a0Uu  
    op.val1 = taq-0.01 'y
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    op.parent = parID T6gugDQ~.  
    AddOperation eID, op Q\pTyNAYn  
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    Print "Set pupil diameter = " & pupilDiam [^rT: %Z  
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    'Update AZ Eye subassembly Description k<aKT?Ek>  
    eID = FindFullName( "Geometry.Arizona Eye" ) ,/d R  
    GetEntity eID, entity lzJ[`i.  
    entity.Description = "Accommodation = " & A & "D" >zYO1.~  
    SetEntity eID, entity ]}KoW?M
 
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    Update ^ :%"Z&  
    Print "DONE!" s:_M+_7_  
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End Sub +(v<_#wR-  
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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： X6+2~'*t  
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Accommodation = 4 Diopters jwm2ZJ
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Pupil Diameter = 4 mm fs8nYgv|Q  
Set aqueous humor thickness = 2.81 :lF[k`S T  
Set anterior lens radius = 10.4 and conic constant = -2.375869 -8sm^A>C  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 
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Set lens thickness = 3.927 wYZ"fusT  
Set lens index of refraction = 1.42672 `t0?PpUo  
Set pupil diameter = 4 ``%uq)G=D  
DONE! 64qm  
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