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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 `%-4>jI9-  
    UF@IBb}0  
    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。 r1i$D  
    1&"-*)  
    模型 <Ctyht0c.  
    %mY|  
    模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 Wgxn`6  
    Eo%UuSi  
    Table 1. AZ眼睛模型的定义
    [f<"p[  
    在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. Zxg1M  
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    光源 M'yO+bu  
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    多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 [^<SLTev  
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    图1. 光源和提示信息使用
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    除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 yZq?B  
    CV'&4oq  
    在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 Xo2^N2I  
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    图2. 字母F光源的设定方法光 "$GK.MP5  
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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 EPc!p>  
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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。 egfi;8]E  
    lp(Nv(S  
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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。 r,5-XB  
    / T ,zZ9=  
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    图5. 视网膜重点采样规格设定
    =(%*LY!Xc  
    脚本 DlDB=N0@S  
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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: DB#$~(o  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
    im=5{PbJ^  
    如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 XJUEwX  
    余下的脚本计算与屈光度有关的所有参数。 cST\~SUm  
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    分析 qmEoqU  
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    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 %*6RzJO6  
    ' PELf P8  
    图7. 字母F在视网膜上颜色分析
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    脚本代码 `qE4U4  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. T8U[xu.>  
    V7:\q^$  
    Dim entity As T_ENTITY K5{{:NR$  
    Dim op As T_OPERATION 4Q;<Q"  
    Dim mat As T_MODELMATERIAL \*uugw,\y  
    Dim A As Double hcyn  
    Dim pupilDiam As Double v;Es^ YI  
    Dim eID As Long ]oEQ4  
    Dim parID As Long ;Z*'D}  
    Dim count As Integer ?;^5ghY$  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double |CwG3&8  
    Dim tlens As Double, nlens As Double ijF V<P  
    Dim curv As Double, conic As Double .3@Ng  
    Dim ok As Long ojoxXly`  
    uoHqL IpQ  
    Sub Main JA<~xo[Q9  
    Pg Syt  
        '用户输入对话框 >b>gr OX  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ]U[&uymax  
            TextBox 220,21,40,21,.TextBox1 'default: 0 ^sV|ck  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 zks#EzQ  
            OKButton 40,91,90,21 )!eEO [\d  
            CancelButton 190,91,90,21 ENq"mwV|  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 !R74J=#(  
            TextBox 220,49,40,21,.TextBox2 'default: 4 LJWTSf"f?  
        End Dialog g2=}G<*0  
        Dim dlg As UserDialog _s*! t  
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        ok = Dialog (dlg) D-pX<0 -y  
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        If ok=0 Then    'cancel button was pressed N<liS3>  
            Print "Execution cancelled." 333u]  
            End !!WJn}  
        End If b66R}=P l  
    )|RZa|`-G  
        'Assign accommodation and pupil diameter & use defaults if field left empty &DLhb90  
        If dlg.TextBox1 = "" Then nhewDDu  
            A = 0           'Default accommodation j=W@P-  
        Else RL*]g*  
            A = CDbl(dlg.TextBox1) \5hw9T&[B  
        End If #h N.=~  
    ]G*$W+G]  
        If dlg.TextBox2 = "" Then 1i'Z ei)  
            pupilDiam = 4   'Default pupil diameter ]_u`EvEx6  
        Else 2ce'fMV  
            pupilDiam = CDbl(dlg.TextBox2) g\&2s,  
        End If vLDi ;  
    !BUi)mo  
        Print " " t8vc@of$c,  
        Print "Accommodation = " & A & " Diopters" TEWAZVE*  
        Print "Pupil Diameter = " & pupilDiam & " mm" Vv4H:BK$  
    \Yq0 zVol  
        ' Calculate new parameters with accommodation c&*l"  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness kOipH |.x  
    %ek"!A  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens Ea]T>4  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens b[srG6{ &  
    TatMf;?h&  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens X$V|+lTk  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens KjOi(YUnq7  
    6m[9b*s7  
        tlens = 3.767 + 0.04*A                  'Lens thickness +"uwV1)b"  
    tS<h8g_  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction j#3m|dQ  
    jDTUXwx7V  
        'Adjust parameters to account for accommodation WNF9#oN|oT  
    b_vTGl1_6  
        '************************************************************************* v`B4(P1Z  
        'Aqueous thickness (Position of Lens) lFf XWNb  
        '************************************************************************* k[9A,N^lZB  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) )0-o%- e  
        GetCustomElement eID, entity # X/Q  
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        parID = FindFullName( "Geometry.Arizona Eye" ) Uh}X<d/V  
    4AHL3@x  
        ' Delete any shift(s) in z A1-qtAO]  
        count = 0 0 d4cE10  
        While GetOperationCount(eID)>count w$>3pQ8d  
            GetOperation eID, count, op H$tb;:  
            If op.Type="ShiftZ" Then :Jl Di>B  
                DeleteOperation eID,count UX_I6_&  
                count=count-1 uyT/Xzo3  
            End If 0H[LS  
            count=count+1 >^3zU   
        Wend FH*RU1Z  
    }bMWTT  
        'Set new shift in Df@/cT  
        op.Type = "ShiftZ" d(S}NH  
        op.val1 = taq uV~e|X "9s  
        op.parent = parID uTGcQs}  
        AddOperation eID, op H/J<Pd$p  
        Print "Set aqueous humor thickness = " & taq-0.55 ~NNv>5 t5  
    J^ ={}  
        '************************************************************************* *#2Rvt*Ox  
        'Radius and conic constant of anterior lens @^? XaU  
        '************************************************************************* <AUWby,"  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) C3S`}o.  
        GetConic eID, entity, curv, conic 'qy#)F  
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        SetConic eID, entity, 1/Rant, CCant *48IF33&s  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant XDYosC:  
    >Z\BfH  
        '************************************************************************* z+3 9ee  
        'Radius and conic constant of posterior lens r7I B{}>-  
        '************************************************************************* %-j&e44  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) nbxR"UH  
        GetConic eID, entity, curv, conic {oWsh)[x2  
    "^%Z'ou  
        SetConic eID, entity, 1/Rpost, CCpost ]US[5)EL-  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 1V%'.l9  
    A1A3~9HuK  
        '************************************************************************* H06Bj(Y!  
        'Lens thickness (Position of posterior lens surface) CLN+I'uX0  
        '************************************************************************* Nn#u%xvJt  
    m;/i<:`  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Vk7=7%xW  
    Uix{"  
        ' Delete any z-shift(s) PayV,8   
        count = 0 ;&?pd"^<_Z  
        While GetOperationCount(eID)>count 9;KJr[FQV  
            GetOperation eID, count, op EXpSh}  
            If op.Type="ShiftZ" Then dWR1cvB(wY  
                DeleteOperation eID,count @J vZ[T/  
                count=count-1 2c:f<>r0y  
            End If ]}LGbv"`A  
            count=count+1 Y\?j0X;  
        Wend ($WE=biZ&  
    {4rQ7J4Ux  
        'Set new z-shift CV^c",b_  
        op.Type = "ShiftZ" -x'e+zT  
        op.val1 = tlens ^?"^Pmw  
        op.parent = parID z{?4*Bq  
        AddOperation eID, op W9R`A  
        Print "Set lens thickness = " & tlens 0"4@;e_)>  
    z[&s5"  
        '************************************************************************* qY(:8yC36  
        'Lens index of refraction r4eUZ .8R  
        '************************************************************************* 9?`RR/w  
        eID = FindMaterial( "Lens" ) +Me2U9  
        GetModelMaterial eID, mat rsF:4G"%  
    i_U}{|j  
        mat.Nd = nlens nNn56&N]  
        SetModelMaterial eID, mat (0jr;jv  
        Print "Set lens index of refraction = " & nlens t(?<#KUB-  
    T;?+kC3  
        '************************************************************************* .JAcPyK^  
        'Pupil diameter .3wY\W8Dr-  
        '************************************************************************* LprM;Q_  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) )=H{5&e#u  
    ]\;xN~l  
        'Adjust pupil diameter (trimming volume inner hole) 3"rkko?A  
    Y}.Ystem  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" F?4Sz#  
    I/s.xk_i  
        ' Adjust pupil location to just in front of the lens GGE[{Gb9  
        parID = FindFullName( "Geometry.Arizona Eye" ) } uQ${]&D  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 3g'+0tEl  
        count = 0 lrys3  
        While GetOperationCount(eID)>count U e*$&VlT  
            GetOperation eID, count, op D ,M@8 h,  
            If op.Type="ShiftZ" Then '_o@V O  
                DeleteOperation eID,count ?`P2'i<b  
                count=count-1 u O'/|[`8  
            End If \P?A7vuhLs  
            count=count+1 A1_ J sS  
        Wend $D_HZ"ytu  
        op.Type = "ShiftZ" }lfn0 %(@  
        op.val1 = taq-0.01 0I zZKRw  
        op.parent = parID dlD}Ub  
        AddOperation eID, op xo~g78jm7,  
    ]Oso#GYD  
        Print "Set pupil diameter = " & pupilDiam T[2}p=<%  
    Lt>7hBe"  
        'Update AZ Eye subassembly Description A3s57.Z]|  
        eID = FindFullName( "Geometry.Arizona Eye" ) l)8sw=  
        GetEntity eID, entity gaeOgP.0  
        entity.Description = "Accommodation = " & A & "D" -e*BqH2t  
        SetEntity eID, entity Yx1 D)  
    g42T#p8^  
        Update \ X$)vK  
        Print "DONE!" 0Q1/n2V  
         ~3=2=Uf  
    End Sub v~5<:0dL  
    9#@Zz4Ww  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: 8p =>?wG  
    oVkr3K Z  
    Accommodation = 4 Diopters rJ(OAKnY  
    Pupil Diameter = 4 mm 93D \R  
    Set aqueous humor thickness = 2.81 Qp!J:YV  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 A,c'g}:  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 I,j3bC  
    Set lens thickness = 3.927 V2Y$yV8g1  
    Set lens index of refraction = 1.42672 D[~}uZ4\  
    Set pupil diameter = 4 #F4X}  
    DONE! 3h&bZ  
    [g|Hj)(  
    Taasi` k  
    QQ:2987619807 Y/P]5: =h  
     
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