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    [分享]Arizona眼睛模型 [复制链接]

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    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 k<N5*k8M  
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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。 ^ ~Tn[w W_  
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    模型 < 5ULu(b&$  
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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。 $V/Ke  
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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. c+whpQ=01  
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    光源 KXWz(L!1  
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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。 n2[h`zm1{B  
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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。 /Vx EqIK  
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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。 ,hT**(W  
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    图2. 字母F光源的设定方法光 : 'jVA  
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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 *Rc?rMF!  
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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。 k6\&[BQs  
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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。 z38Pi  
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    图5. 视网膜重点采样规格设定
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    脚本 |]Y6*uEX<  
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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: GQE7P()  
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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。  (8 /&  
    余下的脚本计算与屈光度有关的所有参数。 {D [z>I;D  
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    分析 Ov.oyke4  
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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。 )|Ka'\xr  
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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 ,z+n@sUR:  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. xBqZ: BQ  
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    Dim entity As T_ENTITY v,iq,p)&  
    Dim op As T_OPERATION EKmn@S-&P  
    Dim mat As T_MODELMATERIAL #V Z js`d6  
    Dim A As Double &m TYMpA  
    Dim pupilDiam As Double b~TTz`HZ  
    Dim eID As Long ?U2 'L2y  
    Dim parID As Long }|znQ3A2\l  
    Dim count As Integer W!* P  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ?|n@ %'  
    Dim tlens As Double, nlens As Double w@,v$4Oi  
    Dim curv As Double, conic As Double \e%%ik,<  
    Dim ok As Long }rWg ']  
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    Sub Main jRW@$ <mG  
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        '用户输入对话框 pM*( kN  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 >h(GmR*xM  
            TextBox 220,21,40,21,.TextBox1 'default: 0 }CrWmJu0  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 KJt6d`ZN  
            OKButton 40,91,90,21 *nV"X0&  
            CancelButton 190,91,90,21 acj-*I  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 q3GkfgY  
            TextBox 220,49,40,21,.TextBox2 'default: 4 MK!Aq^Jz  
        End Dialog >U]KPL[%  
        Dim dlg As UserDialog k#8E9/ t@  
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        ok = Dialog (dlg) a!;#u 8f  
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        If ok=0 Then    'cancel button was pressed Ghar hJ>v  
            Print "Execution cancelled." 9aKO||i,  
            End iY5V4Gbo  
        End If <." @H<-`*  
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        'Assign accommodation and pupil diameter & use defaults if field left empty `9acR>00$  
        If dlg.TextBox1 = "" Then !=6\70lJ  
            A = 0           'Default accommodation $JiypX^DOP  
        Else [|(=15;  
            A = CDbl(dlg.TextBox1) #E_<}o  
        End If  C8} ;,  
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        If dlg.TextBox2 = "" Then Lw<.QMN%f  
            pupilDiam = 4   'Default pupil diameter va0}?fy.O%  
        Else ? Q"1zcX  
            pupilDiam = CDbl(dlg.TextBox2) 9A9T'g)Du  
        End If &{ZUY3  
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        Print " " sR)jZpmC(  
        Print "Accommodation = " & A & " Diopters" vXG?8Q  
        Print "Pupil Diameter = " & pupilDiam & " mm"  nL[G@1nR  
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        ' Calculate new parameters with accommodation SU jo%3R  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness _SU6Bd/>  
    y8} /e@&  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens  eAG)+b  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens D?4bp'0 3  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Hk=HO|&<XB  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 'UC1!Z  
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        tlens = 3.767 + 0.04*A                  'Lens thickness j@{dsS: 6  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction s3 VD6xi7  
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        'Adjust parameters to account for accommodation Tf('iZ2+  
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        '************************************************************************* QH?sx k2  
        'Aqueous thickness (Position of Lens) Fe.90)  
        '************************************************************************* aDu[iaZ  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) dAy\IfZX=  
        GetCustomElement eID, entity L<6nM ;d  
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        parID = FindFullName( "Geometry.Arizona Eye" ) js% n]$N  
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        ' Delete any shift(s) in z [\  &2&  
        count = 0 d$Y_vX<  
        While GetOperationCount(eID)>count (B! DBnq  
            GetOperation eID, count, op Qraa0]56  
            If op.Type="ShiftZ" Then Np/vPaAk  
                DeleteOperation eID,count WuTkYiF  
                count=count-1 DgB;6Wl  
            End If G#A6<e/  
            count=count+1 s^Xs*T@~h  
        Wend Z$zX%w  
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        'Set new shift in +[4y)y`  
        op.Type = "ShiftZ" jB l$r{L  
        op.val1 = taq vG\ b `  
        op.parent = parID <`wOy [e  
        AddOperation eID, op .i^ @v<+  
        Print "Set aqueous humor thickness = " & taq-0.55 7zIfsb  
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        '************************************************************************* 'pB?  
        'Radius and conic constant of anterior lens 14*6+~38m&  
        '************************************************************************* ef/43+F^x  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" )  QS1lg  
        GetConic eID, entity, curv, conic )<qL8#["U  
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        SetConic eID, entity, 1/Rant, CCant Ex skd}  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant yB 'C9wEH  
    ;' H\s  
        '************************************************************************* !!w(`kmn1  
        'Radius and conic constant of posterior lens k4E9=y?  
        '************************************************************************* W=OryEV?  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) NytodVZ'3  
        GetConic eID, entity, curv, conic \,r* -jr  
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        SetConic eID, entity, 1/Rpost, CCpost *xY3F8  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost %~,Fe7#p  
    Hi*|f!,H?  
        '************************************************************************* eKZS_Qd  
        'Lens thickness (Position of posterior lens surface) AlkHf]oB  
        '************************************************************************* 5)5yH bS  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) PsD)]V9%:  
    uZ'Z-!=CL  
        ' Delete any z-shift(s) g,W34*7=Q  
        count = 0 Of-xGo YZ  
        While GetOperationCount(eID)>count c]bG5  
            GetOperation eID, count, op [x]~G  
            If op.Type="ShiftZ" Then pS}IU{#;  
                DeleteOperation eID,count 1LAd5X  
                count=count-1 {J,4g:4G  
            End If %r*,m3d  
            count=count+1 KWAd~8,mk  
        Wend S\Le;,5Z  
    He}?\C Bo  
        'Set new z-shift o=K9\l  
        op.Type = "ShiftZ" LsaX HI/?b  
        op.val1 = tlens B692Mn  
        op.parent = parID w{So(AF  
        AddOperation eID, op }maD8,:t  
        Print "Set lens thickness = " & tlens hZ!kh3@:`  
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        '************************************************************************* z( }w|  
        'Lens index of refraction 8eYEi  
        '************************************************************************* *::.Uo4O  
        eID = FindMaterial( "Lens" ) 5X>~39(r  
        GetModelMaterial eID, mat #y[omla8  
    @^  *62  
        mat.Nd = nlens ,2+d+Zuh  
        SetModelMaterial eID, mat MNb9~kM  
        Print "Set lens index of refraction = " & nlens CDsl)  
    T?6<1nU)  
        '************************************************************************* %lGOExV%  
        'Pupil diameter DS>&|zF5l  
        '************************************************************************* mH4u@aQ}  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 2oRwDg&7|  
    %<[{zd1C-  
        'Adjust pupil diameter (trimming volume inner hole) 9F?-zn;2s  
    [{Q$$aV1  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Un,'a8>V`  
    (E&M[hH+  
        ' Adjust pupil location to just in front of the lens S]~5iO_bst  
        parID = FindFullName( "Geometry.Arizona Eye" ) q9{)nU  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) /!A"[Tyt  
        count = 0 P8|ANe1 v  
        While GetOperationCount(eID)>count AI#.+PrC{/  
            GetOperation eID, count, op "5O>egt  
            If op.Type="ShiftZ" Then EltCtfm`  
                DeleteOperation eID,count qSG0TWD!pq  
                count=count-1 }4H}*P>+  
            End If r]D U  
            count=count+1 y'I m/{9U  
        Wend ?!/8~'xA6  
        op.Type = "ShiftZ" 5>daWmD  
        op.val1 = taq-0.01 ksuePMIK  
        op.parent = parID D %)L "5C  
        AddOperation eID, op m)"(S  
    B8n[ E  
        Print "Set pupil diameter = " & pupilDiam Dq$1 j%4Y  
    ?A_+G 5  
        'Update AZ Eye subassembly Description vNuws_  
        eID = FindFullName( "Geometry.Arizona Eye" ) js"5{w&  
        GetEntity eID, entity e*PUs  
        entity.Description = "Accommodation = " & A & "D" W*CRxGyZCl  
        SetEntity eID, entity |YyNqwP`,  
    "kBVHy  
        Update ^_DwuY  
        Print "DONE!" vM5/KrW  
         b7I0R; Zj  
    End Sub Ak('4j!*}^  
    *AGf'+j*z  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: yt="kZ  
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    Accommodation = 4 Diopters ~u2f`67{  
    Pupil Diameter = 4 mm qGEp 6b H  
    Set aqueous humor thickness = 2.81 w5~j|c=_W  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 `XK\', }F  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 II.: k.D`  
    Set lens thickness = 3.927 cc_'Kv!  
    Set lens index of refraction = 1.42672 a|oh Ad  
    Set pupil diameter = 4 .r6x9t  
    DONE! hhZ%{lqL  
    Ng*-Bw)p]  
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    QQ:2987619807 f+n {9Hz  
     
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