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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 e@3SF  
    M;A_'h?Z  
    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。 ,%pCcM)  
    l*ltS(?  
    模型 f&-`+V}U  
    #Xg;E3BM  
    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。 b(K"CL\p  
    p6JTNx D  
    Table 1. AZ眼睛模型的定义
    gT}H B.  
    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. #*(}%!rD*  
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    光源 7L~ *%j  
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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|LHnNQ  
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    图1. 光源和提示信息使用
    +wi=IrRr  
    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。 ZU 3Psj  
    ,{*g Q%7  
    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。 .s{ "NqRA  
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    图2. 字母F光源的设定方法光 6Zi{gx  
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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 KjGu !B  
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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。 *fN+wiPD  
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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。 sH6;__e  
    $N?8[  
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    图5. 视网膜重点采样规格设定
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    脚本 \%7*@&  
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    内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: [CQR  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
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    如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 FJvY`zqB  
    余下的脚本计算与屈光度有关的所有参数。 yTZev|ej@  
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    分析 *'((_ NZ>  
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    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 &nEL}GM)E  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 eiK_JPFA-  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. w)dnmrKDZg  
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    Dim entity As T_ENTITY s#?ZwD,=  
    Dim op As T_OPERATION ]N'3jf`W  
    Dim mat As T_MODELMATERIAL zQ,rw[C"W  
    Dim A As Double y% bIO6u:  
    Dim pupilDiam As Double <-I69`  
    Dim eID As Long KF(H >gs  
    Dim parID As Long PK]3uh  
    Dim count As Integer J,}h{-Xy`  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double +a5F:3$  
    Dim tlens As Double, nlens As Double H )ej]DXy  
    Dim curv As Double, conic As Double bYsX?0T!p  
    Dim ok As Long R`(2Fy%0\k  
    `2Pa{g- .  
    Sub Main G)am ng/  
    n&[CTOV  
        '用户输入对话框 5/"$ _7"{a  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Ty g>Xv  
            TextBox 220,21,40,21,.TextBox1 'default: 0 ` aVp#  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 *(9Tl]w  
            OKButton 40,91,90,21 >jt2vU@t.  
            CancelButton 190,91,90,21 [ U:C62oK,  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 +d3|Up8=  
            TextBox 220,49,40,21,.TextBox2 'default: 4 / l$enexSt  
        End Dialog ]PS`"o,pF$  
        Dim dlg As UserDialog >~o- 6g  
    2+9VDf2  
        ok = Dialog (dlg) zsp%Cz7T  
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        If ok=0 Then    'cancel button was pressed 8^>qor.]M  
            Print "Execution cancelled." x7S\-<8  
            End UF+Qx/4h0  
        End If g~DuK|+  
    3^/w`(-{@  
        'Assign accommodation and pupil diameter & use defaults if field left empty M@ U >@x;  
        If dlg.TextBox1 = "" Then ?c#s}IH  
            A = 0           'Default accommodation L-|l$Ti"  
        Else 03~ ADj  
            A = CDbl(dlg.TextBox1) W %*#rcdq  
        End If afrF%!  
    D40 vCax^J  
        If dlg.TextBox2 = "" Then Ll]5u~  
            pupilDiam = 4   'Default pupil diameter neFwxS?  
        Else zxn|]P bS  
            pupilDiam = CDbl(dlg.TextBox2) ]y@A=nR  
        End If z$J m1l  
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        Print " " C5~~$7k0  
        Print "Accommodation = " & A & " Diopters" WFF?VBT'^  
        Print "Pupil Diameter = " & pupilDiam & " mm" COw"6czX/  
    1Dr&BXvf]8  
        ' Calculate new parameters with accommodation w5>[hQR\  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ei5YxV6I  
    F{x+1hct0  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens 8 W  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens qPPe)IM'Sc  
    Wk[a|>  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens FI^Wh7J  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens LhL |ETrJ  
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        tlens = 3.767 + 0.04*A                  'Lens thickness M/ 64`lcb  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction SW9 C 8Q  
    CzBYH   
        'Adjust parameters to account for accommodation PMAz[w,R~  
    }PI:O%N;  
        '************************************************************************* h7#\]2U$[5  
        'Aqueous thickness (Position of Lens) e0(/(E:  
        '************************************************************************* f\2IKpF2  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 27!F B@k-  
        GetCustomElement eID, entity $M}"u [Qq  
    MG=E 6:  
        parID = FindFullName( "Geometry.Arizona Eye" ) `jeATxWv  
    'x%gJi#  
        ' Delete any shift(s) in z ) ^ En  
        count = 0 "}71z  
        While GetOperationCount(eID)>count Ll|-CY $  
            GetOperation eID, count, op NO~G4PUM0C  
            If op.Type="ShiftZ" Then v]cw})l  
                DeleteOperation eID,count J.UNw8z  
                count=count-1 9G[ DuYJI  
            End If k7U.]#5V  
            count=count+1 IP`lx  
        Wend FxlH;'+Q  
    A}lxJ5h0  
        'Set new shift in UV2W~g  
        op.Type = "ShiftZ" nVs@DH  
        op.val1 = taq /bykIUTKI  
        op.parent = parID 54p{J  
        AddOperation eID, op %6q82}#`  
        Print "Set aqueous humor thickness = " & taq-0.55 @1o X&#  
    $z_yx `5  
        '************************************************************************* 20}HTV{v  
        'Radius and conic constant of anterior lens 5M=U*BI  
        '*************************************************************************  N}5  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) JL,Y9G*]s  
        GetConic eID, entity, curv, conic S})f`X9_}  
    '@Uu/~;h  
        SetConic eID, entity, 1/Rant, CCant )1 -<v);  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant U$5x#{AFp  
    fnX[R2KZ  
        '************************************************************************* @K <Onh`  
        'Radius and conic constant of posterior lens {H/%2  
        '************************************************************************* {|oWU8.l  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) u4hn9**a1  
        GetConic eID, entity, curv, conic suQTi'K1  
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        SetConic eID, entity, 1/Rpost, CCpost _S) K+C|@  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost K3mP6Z#2  
    bhD-;Y!6;  
        '************************************************************************* Gbhw7 (&  
        'Lens thickness (Position of posterior lens surface) (wL$ h5SG  
        '************************************************************************* hj1;f<' U  
    Sqi9'-%m  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) t0f7dU3e;L  
    Zd-qBOB2L  
        ' Delete any z-shift(s) +Kgl/Wg%  
        count = 0 V%4P.y  
        While GetOperationCount(eID)>count waMV6w)<  
            GetOperation eID, count, op ]?]M5rP  
            If op.Type="ShiftZ" Then _=0Ja S>M.  
                DeleteOperation eID,count !BVCuuM>w  
                count=count-1 >8/Otg+h  
            End If - G>J  
            count=count+1 bqH [-mu6  
        Wend %1TKgNf  
    mo<*h&;&  
        'Set new z-shift rd&d~R6  
        op.Type = "ShiftZ" ;>2-  
        op.val1 = tlens K\ Wzh;  
        op.parent = parID 5 Y&`ZJ  
        AddOperation eID, op T"P}`mT  
        Print "Set lens thickness = " & tlens 9X*Z\-  
    Aq(cgTNW  
        '************************************************************************* r ??_2>Q  
        'Lens index of refraction O^\:J 2I(  
        '************************************************************************* %( OP  [  
        eID = FindMaterial( "Lens" ) AO`@ &e]o  
        GetModelMaterial eID, mat hbYstK;]Z  
    D 6'd&U{_  
        mat.Nd = nlens :JSxsA6 k  
        SetModelMaterial eID, mat 7[=G;2<  
        Print "Set lens index of refraction = " & nlens jS]Saqd  
    %!iqJ)*~  
        '************************************************************************* !Fs$W  
        'Pupil diameter 5@l5exuG*m  
        '************************************************************************* -Y+pLvG*  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ~ ?nn(Q-  
     pF6u3]  
        'Adjust pupil diameter (trimming volume inner hole) `ZL^+h<b>M  
    TNh&g.  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Otu?J_d3  
    h];H]15&  
        ' Adjust pupil location to just in front of the lens w &YUb,{Y  
        parID = FindFullName( "Geometry.Arizona Eye" ) N^B7<~ bD  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) $MvKwQ/  
        count = 0 P 4)Q5r  
        While GetOperationCount(eID)>count 5 `TMqrk  
            GetOperation eID, count, op f'ld6jt|%  
            If op.Type="ShiftZ" Then VEa"^{,w  
                DeleteOperation eID,count &(<>} r  
                count=count-1 ]4B;M Ym*  
            End If t$qIJt$  
            count=count+1 #O_%!7M{4  
        Wend jh z*Y}MX  
        op.Type = "ShiftZ" VS4Glx73  
        op.val1 = taq-0.01 Ib{#dhV  
        op.parent = parID CV HKP[-  
        AddOperation eID, op $-^& AKc  
    +D @B eQu  
        Print "Set pupil diameter = " & pupilDiam gHh (QRA  
    YL`MLt4MC  
        'Update AZ Eye subassembly Description h7ZH/g$)  
        eID = FindFullName( "Geometry.Arizona Eye" ) M%54FsV  
        GetEntity eID, entity B!<B7Q  
        entity.Description = "Accommodation = " & A & "D" 6t!=k6`1  
        SetEntity eID, entity v@G&";|  
    =M:Po0?0E  
        Update ?v,c)  
        Print "DONE!" [ {"x{;  
         >l-u{([B  
    End Sub OS%[SHs  
    JkR%o #>5  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: #Qg)4[pMJ  
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    Accommodation = 4 Diopters {pi_yr3  
    Pupil Diameter = 4 mm 7gLk~*  
    Set aqueous humor thickness = 2.81 3Yx'/=]  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 XU<owk  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 ":e6s co  
    Set lens thickness = 3.927 4T52vM  
    Set lens index of refraction = 1.42672 yS K81`  
    Set pupil diameter = 4 ?.ObHV*k  
    DONE! `B&E?x  
    P$Y w'3v/  
    > mCH!ey  
    QQ:2987619807 |,KsJ2hD  
     
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