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    [分享]Arizona眼睛模型 [复制链接]

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    离线infotek
     
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    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 };sMU6e  
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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。 ;&,.TC?l  
    m:{tgcE  
    模型 gj+3y9  
    *{5>XH{ x  
    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。 8#59iQl  
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    Table 1. AZ眼睛模型的定义
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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. \L[i9m|e  
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    光源 \+Y!ILOI  
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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。 SLoo:)  
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    图1. 光源和提示信息使用
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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。  Q2\  
    ]}LGbv"`A  
    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。 2P5_zND  
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    图2. 字母F光源的设定方法光 F~_;o+e;X  
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    图3. 字母F在视网膜上位置点列图
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    视网膜的散射 6^YJ]w  
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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。 .ECHxDp  
    nyhMnp#<  
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    图4. 视网膜朗伯散射设定
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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。 xb$yu.c  
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    图5. 视网膜重点采样规格设定
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    脚本 8/Rm!.8+~  
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    内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: gfo}I2"  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
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    如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 b!a %YLL  
    余下的脚本计算与屈光度有关的所有参数。 >oqZ !V5[  
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    分析 v>-Y uS  
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    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 ybvI?#  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 DO^y;y>  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. QIAR  
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    Dim entity As T_ENTITY R6@uM<  
    Dim op As T_OPERATION lbkL yp2  
    Dim mat As T_MODELMATERIAL rn" pKUd  
    Dim A As Double o'Y#H r)/  
    Dim pupilDiam As Double ;~/4d-  
    Dim eID As Long !N~*EI$  
    Dim parID As Long E`xU m9F  
    Dim count As Integer Y';>O`  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double zj20;5o>U&  
    Dim tlens As Double, nlens As Double <t}?$1  
    Dim curv As Double, conic As Double qrDcL>Hrn  
    Dim ok As Long S< x:t(  
    yJ/#"z=h?  
    Sub Main b UvK  
    gX*K&*q   
        '用户输入对话框 $Jf9;.  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ,- HIFbXx@  
            TextBox 220,21,40,21,.TextBox1 'default: 0 hKksVi  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 :s*>W$Wp4  
            OKButton 40,91,90,21 #&siHHs \  
            CancelButton 190,91,90,21 .,mPdVof  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 OoaY  
            TextBox 220,49,40,21,.TextBox2 'default: 4 -1 W  
        End Dialog \cZfg%PN  
        Dim dlg As UserDialog D#v?gPo4  
    SE!L :  
        ok = Dialog (dlg) f z%tA39m  
    OCW+?B;  
        If ok=0 Then    'cancel button was pressed B||c(ue  
            Print "Execution cancelled." x!?Z *v@I  
            End t!jwY/T  
        End If O5;-Om  
    ;r!\-]5$  
        'Assign accommodation and pupil diameter & use defaults if field left empty w3bIb$12  
        If dlg.TextBox1 = "" Then <SQ(~xYi  
            A = 0           'Default accommodation 0QoLS|voA/  
        Else j9xXKa5  
            A = CDbl(dlg.TextBox1) ;3 UvkN  
        End If s.y}U5Ty?P  
    Dl\d_:+  
        If dlg.TextBox2 = "" Then sqG`"O4W  
            pupilDiam = 4   'Default pupil diameter EcW1;wH  
        Else &@; RI~  
            pupilDiam = CDbl(dlg.TextBox2) q\H7& w  
        End If k7Oy5$##  
    3bts7<K=  
        Print " " %6]\^  
        Print "Accommodation = " & A & " Diopters" M(5D'4.  
        Print "Pupil Diameter = " & pupilDiam & " mm" h5!d  
    -+P7:4/  
        ' Calculate new parameters with accommodation mV zu~xym  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness D rTM$)  
    k1iLnza%  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens {^wdJZ~QLK  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens gj;@?o0  
    @1.9PR$x  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens o?dR\cxj  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens P)IjL&[  
    W5I=X] &  
        tlens = 3.767 + 0.04*A                  'Lens thickness >zR14VO`_|  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction T*\$<-^  
    ;eh/_hPM  
        'Adjust parameters to account for accommodation 3{pk5_c  
    JUU&Z[6J  
        '************************************************************************* cY~M4:vgT  
        'Aqueous thickness (Position of Lens) \G3!TwC%  
        '************************************************************************* 0||F`24  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) P;c0L;/  
        GetCustomElement eID, entity f".q9{+p,  
    %M6 c0d[9-  
        parID = FindFullName( "Geometry.Arizona Eye" ) +-P<CCvWz  
    -<d(  
        ' Delete any shift(s) in z h0XH`v  
        count = 0 "Q?_ EEn  
        While GetOperationCount(eID)>count 1p=&WM  
            GetOperation eID, count, op I-{^[pp  
            If op.Type="ShiftZ" Then %/%gMRXG2  
                DeleteOperation eID,count <Wf0QO,  
                count=count-1 b[0S=e G  
            End If %`oHemSy  
            count=count+1 `WlH*p)z9  
        Wend C9pnU,[  
    - 3]|[  
        'Set new shift in ,-:a?#f>  
        op.Type = "ShiftZ" to51hjV  
        op.val1 = taq [DhEh@  
        op.parent = parID ?OO%5PSen  
        AddOperation eID, op B~rU1Y)  
        Print "Set aqueous humor thickness = " & taq-0.55 B{99gwMe]  
    b- uZ"Kf^  
        '************************************************************************* 0@v 2*\D#  
        'Radius and conic constant of anterior lens 8~qlLa>jc  
        '************************************************************************* -xTKdm D  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) S ;h&5.p  
        GetConic eID, entity, curv, conic UEN56@eCNf  
    1x;@~yU  
        SetConic eID, entity, 1/Rant, CCant `fMpV8vv  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 94YA2_f;  
    nqeVV&b!  
        '************************************************************************* HSC6;~U  
        'Radius and conic constant of posterior lens -U:2H7  
        '************************************************************************* ?cJA^W  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) ( QKsB3X  
        GetConic eID, entity, curv, conic }v&K~!*  
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        SetConic eID, entity, 1/Rpost, CCpost cTy'JT7  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost u9,=po=+7f  
    G}q<{<+$  
        '************************************************************************* FXxN>\76.  
        'Lens thickness (Position of posterior lens surface) 2;h+;G  
        '************************************************************************* I<KCt2:X  
    hWm0$v 1p  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) tStJ2-5*t  
    /wlFD,+8  
        ' Delete any z-shift(s) d96fjj~  
        count = 0 ]h0Y8kpd  
        While GetOperationCount(eID)>count D>S8$]^Dm  
            GetOperation eID, count, op G-ZhGbAI7  
            If op.Type="ShiftZ" Then Eny!R@u7q  
                DeleteOperation eID,count oo\IS\  
                count=count-1 d#4Wj0x  
            End If !x6IV25  
            count=count+1 yE<,Z%J[n  
        Wend 0yKh p: ^  
    c{ 7<H  
        'Set new z-shift CxkMhd8qz  
        op.Type = "ShiftZ" l*qk1H"g  
        op.val1 = tlens 3+j^E6@  
        op.parent = parID PH[4y:^DN  
        AddOperation eID, op z41D^}b  
        Print "Set lens thickness = " & tlens 4':MI|/my_  
    9V.+U7\w  
        '************************************************************************* ZDfS0]0F  
        'Lens index of refraction >6w@{p2B  
        '************************************************************************* K(' 9l& A  
        eID = FindMaterial( "Lens" ) K1<k+t/V  
        GetModelMaterial eID, mat zWJKYFqK  
    fs7~NY  
        mat.Nd = nlens KjC[q  
        SetModelMaterial eID, mat waBRQh  
        Print "Set lens index of refraction = " & nlens @ }ZGY^  
    b#e]1Q  
        '************************************************************************* i:;$oT  
        'Pupil diameter $4sA nu]  
        '************************************************************************* _@7(g(pY 3  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 7bHE!#L`0  
    <Nvlk\LQ  
        'Adjust pupil diameter (trimming volume inner hole) 0,bt^a  
    xJ$Rs/9C  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" S3nB:$_-;  
    ykJ+%gla  
        ' Adjust pupil location to just in front of the lens DZ,<Jmg&e*  
        parID = FindFullName( "Geometry.Arizona Eye" ) BF>T*Z-Ki  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) )7tV*=?Ic8  
        count = 0 cl ?< 7  
        While GetOperationCount(eID)>count * q+oeAYX  
            GetOperation eID, count, op LE<:.?<Z-  
            If op.Type="ShiftZ" Then .vN)A *  
                DeleteOperation eID,count JATS6-Lz`  
                count=count-1 iOKr9%9?Z  
            End If :vw0r`  
            count=count+1 ZBPd(;"x+  
        Wend 2-QuT"Gkd  
        op.Type = "ShiftZ" }5QZ6i#  
        op.val1 = taq-0.01 tWcizj;?wK  
        op.parent = parID kx:c*3q.k  
        AddOperation eID, op K<D`(voL  
    | pF5`dX  
        Print "Set pupil diameter = " & pupilDiam V|+ `L-  
    P)a("XnJ`  
        'Update AZ Eye subassembly Description N'htcC  
        eID = FindFullName( "Geometry.Arizona Eye" ) 8}Fw%;Cb  
        GetEntity eID, entity od;Bb  
        entity.Description = "Accommodation = " & A & "D" bXa %EMF  
        SetEntity eID, entity USlF+RY@3L  
    dl7Riw-J  
        Update ,w,ENU0~f  
        Print "DONE!" 1'(_>S5CG  
         )e @01l  
    End Sub 38Bnf  
    j0ci~6&b3_  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: x8\E~6`,  
    nh _DEPMq  
    Accommodation = 4 Diopters d;;>4}XJ]  
    Pupil Diameter = 4 mm b #o}=m  
    Set aqueous humor thickness = 2.81 a7ub.9>  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 AsTMY02|  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 >1#DPU(g  
    Set lens thickness = 3.927 Oex{:dO "F  
    Set lens index of refraction = 1.42672 #j(q/ T{x  
    Set pupil diameter = 4 c#]'#+aH  
    DONE! U>e3_td3,  
    9^6|ta0;0  
    ;u4@iN}p  
    QQ:2987619807 (O M?aW  
     
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