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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 YgNt>4K  
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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。 //nR=Dy{  
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    模型 dq28Y$9~  
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    模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 WLd{+y5#  
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    Table 1. AZ眼睛模型的定义
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    在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. xAw$bJj~s  
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    光源 U+F?b\  
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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。 Xi^3o  
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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。 1P:r=Rt/  
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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。 97lM*7h;  
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    图2. 字母F光源的设定方法光 oMawIND a  
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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 I&?(=i)N  
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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。 ]ppi962Z  
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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。 w?)v#]<-  
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    图5. 视网膜重点采样规格设定
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    脚本 y! he<4  
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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: 9otA5I^v  
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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。 ++d(}^C;  
    余下的脚本计算与屈光度有关的所有参数。 g+;)?N*j  
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    分析 /fC@T  
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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。 z/6/   
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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 ~WXT0-,  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. WBD e`  
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    Dim entity As T_ENTITY vH/ z|<  
    Dim op As T_OPERATION =!u9]3)  
    Dim mat As T_MODELMATERIAL Y^80@MJ  
    Dim A As Double }#}IR5`=E  
    Dim pupilDiam As Double SQ!wq  
    Dim eID As Long [ fvip_Pt  
    Dim parID As Long VP[ -BK[  
    Dim count As Integer ,_;+H*H>"  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 'zCJK~x`x  
    Dim tlens As Double, nlens As Double vH/<!jtI  
    Dim curv As Double, conic As Double H }w"4s  
    Dim ok As Long Ylbh_ d~BU  
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    Sub Main gM_z`H 5[!  
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        '用户输入对话框 7|4hs:4mD  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 c@9jc^CJ  
            TextBox 220,21,40,21,.TextBox1 'default: 0 V ;Kzh$^rk  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 vJ5`:4n"  
            OKButton 40,91,90,21 7L~LpB  
            CancelButton 190,91,90,21 <Wc98m  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 N!Dc\d=8q]  
            TextBox 220,49,40,21,.TextBox2 'default: 4 >;V ? s]  
        End Dialog E*VUP 5E  
        Dim dlg As UserDialog ~XAtt\WS  
    ]"bkB+I  
        ok = Dialog (dlg) 9Fb|B  
    }YUUCq&  
        If ok=0 Then    'cancel button was pressed Zwy8 SD'L  
            Print "Execution cancelled." [P,YW|:n  
            End Hik8u!#P  
        End If n+Ofbiz@  
    %-ih$ZY  
        'Assign accommodation and pupil diameter & use defaults if field left empty F02S(WWo;  
        If dlg.TextBox1 = "" Then <SM{yMz  
            A = 0           'Default accommodation <L|eY(:  
        Else `H+~LVH  
            A = CDbl(dlg.TextBox1) Ar&]/X,WG  
        End If #hL<9j  
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        If dlg.TextBox2 = "" Then 2>~{.4PI  
            pupilDiam = 4   'Default pupil diameter 86Q\G.h7  
        Else }G^Bc4@b  
            pupilDiam = CDbl(dlg.TextBox2) \2cbZQx  
        End If !wH7;tU  
    2 mM0\ja  
        Print " " 9>~UqP9  
        Print "Accommodation = " & A & " Diopters" 48X;'b,h  
        Print "Pupil Diameter = " & pupilDiam & " mm" ;0*T7l  
    s+Qm/ h2  
        ' Calculate new parameters with accommodation lK;/97Ze  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness {SH +lX0]{  
    8joJ e>9VJ  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens jR~2mf!h*e  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens Gy{C*m7Q  
    d{_tOj$  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 0l#{7^e  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 5G.A\`u%  
    ,EPs>#d  
        tlens = 3.767 + 0.04*A                  'Lens thickness -:9E+b  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction l!Q |]-.@  
    #fg RF  
        'Adjust parameters to account for accommodation ow:}NI  
    \ZdV|23  
        '************************************************************************* 6itp Mck  
        'Aqueous thickness (Position of Lens) bni :B?#  
        '************************************************************************* (QQ/I;  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) C~o6]'+F_  
        GetCustomElement eID, entity g Z3VT{  
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        parID = FindFullName( "Geometry.Arizona Eye" ) mo%9UL,#W  
    .<JD'%?"  
        ' Delete any shift(s) in z "B`yk/GM]  
        count = 0 y7M"Dr%t^  
        While GetOperationCount(eID)>count e-<fkU9^W  
            GetOperation eID, count, op YpQ/ )fSEV  
            If op.Type="ShiftZ" Then =x "N0p  
                DeleteOperation eID,count [uOW\)`  
                count=count-1 [~$Ji&Dd  
            End If Ko%&~C_  
            count=count+1 (:3rANY|  
        Wend S9X~<!]  
    k#k!AcC  
        'Set new shift in F?2(U\k#  
        op.Type = "ShiftZ" *au&ODa  
        op.val1 = taq }vBk ,ED  
        op.parent = parID Zab5"JR  
        AddOperation eID, op \~ O6S`,  
        Print "Set aqueous humor thickness = " & taq-0.55 cWIX!tc8  
    pE >~F  
        '************************************************************************* -05zcIVo  
        'Radius and conic constant of anterior lens |YjuaXd7N  
        '************************************************************************* YIs(Q  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) rC~hjViG.  
        GetConic eID, entity, curv, conic rlu{C4l  
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        SetConic eID, entity, 1/Rant, CCant A S;ra,x  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ji {V#  
    bG nBV7b  
        '************************************************************************* :,<e  
        'Radius and conic constant of posterior lens \2i4]V  
        '************************************************************************* m;o \.s  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) *g&[?y`UC  
        GetConic eID, entity, curv, conic MO)N0{.b  
    Er} xB~<t  
        SetConic eID, entity, 1/Rpost, CCpost "^~f.N  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost CD1}.h  
    (_-<3)q4  
        '************************************************************************* w C]yE\P1  
        'Lens thickness (Position of posterior lens surface) %t M]|!yw  
        '************************************************************************* }_}C ^  
    M9*7r\hqYV  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) pc}Q_~e  
    e $QX?y .  
        ' Delete any z-shift(s) X tZ0z?  
        count = 0 Bn*D<<{T  
        While GetOperationCount(eID)>count 5T}$+R0&  
            GetOperation eID, count, op W|~Lmdzj  
            If op.Type="ShiftZ" Then Q/4g)(~J  
                DeleteOperation eID,count AR'q2/cw  
                count=count-1 I"*g-ji0  
            End If  ~d_Z?Z  
            count=count+1 uy{mSx?td  
        Wend %*]3j^b Q+  
    2;.7c+r0  
        'Set new z-shift =3lUr<Ze  
        op.Type = "ShiftZ" O-:#Q(H!  
        op.val1 = tlens [(}f3W&  
        op.parent = parID '#[U7(lIQ  
        AddOperation eID, op ^dH#n~Wx0  
        Print "Set lens thickness = " & tlens Y[Us"K`  
    <QT u"i  
        '************************************************************************* rP,i,1Ar 4  
        'Lens index of refraction qQ%zSJ?  
        '************************************************************************* pu nc'~  
        eID = FindMaterial( "Lens" ) AS`0.RC-  
        GetModelMaterial eID, mat GEfX,9LF&  
    /lDW5;d  
        mat.Nd = nlens RvV4SlZz  
        SetModelMaterial eID, mat =K{$?%"  
        Print "Set lens index of refraction = " & nlens y.5mYQA4=[  
    K,%H*1YKK  
        '*************************************************************************  (:].?o  
        'Pupil diameter vG#|CO9  
        '************************************************************************* wlBdA  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 2fTkHBhn&  
    ~ C6< 75  
        'Adjust pupil diameter (trimming volume inner hole) G+AD &EHV  
    c3&F\3  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ja70w:ja  
    d|]F^DDuI  
        ' Adjust pupil location to just in front of the lens r Y|'<$wvg  
        parID = FindFullName( "Geometry.Arizona Eye" ) #*#4vMk<  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 8dq{.B?  
        count = 0 D|9C|q  
        While GetOperationCount(eID)>count o %A4wEye  
            GetOperation eID, count, op %l[Cm4  
            If op.Type="ShiftZ" Then :1eI"])(  
                DeleteOperation eID,count `rW{zQYM  
                count=count-1 P1 =bbMk  
            End If 3lhXD_Y  
            count=count+1 i;*c|ma1>  
        Wend $&nF1HBI4  
        op.Type = "ShiftZ" Pk[f_%0  
        op.val1 = taq-0.01 j{>E.F2.  
        op.parent = parID g$kK)z  
        AddOperation eID, op ;SeDxyKG  
    &1893#V  
        Print "Set pupil diameter = " & pupilDiam )QaI{ z  
    _)p@;vGV  
        'Update AZ Eye subassembly Description I(P|`"  
        eID = FindFullName( "Geometry.Arizona Eye" ) W!.UMmw`  
        GetEntity eID, entity $$<9tqA  
        entity.Description = "Accommodation = " & A & "D" >BMJA:j  
        SetEntity eID, entity 7<x0LW  
    : RnjcnR  
        Update vLD Ma>  
        Print "DONE!" t= "EbPE  
         =t<!W  
    End Sub |^C?~g  
    pZ+zm6\$  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: ./jkY7 k  
    j\q1b:pE  
    Accommodation = 4 Diopters I/jMe'Kp  
    Pupil Diameter = 4 mm 39S}/S)  
    Set aqueous humor thickness = 2.81 %MU<S9k  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 ,AGK O,w  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 FoWE<  
    Set lens thickness = 3.927 \K`AO{ D@  
    Set lens index of refraction = 1.42672 4otB1{  
    Set pupil diameter = 4 *'`ByS  
    DONE! z 4Qz9#*"^  
    !sEI|47{  
    b.47KJzt  
    QQ:2987619807 8<0H(lj7_  
     
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