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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 -KbO[b\V  
    <MO40MP  
    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。 %NlmLWF.  
    b; ;y|H  
    模型 N0D5N(kH%  
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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。 w U]8hkl?  
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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. T|oDJ]\J  
    ]+^4Yq>2  
    光源 PMQ31f/zf  
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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。 )"P.n-aF  
    Nt<Ac&6 s  
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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。 c7?|Tipc  
    >i1wB!gc8  
    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。 JP]4* l  
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    图2. 字母F光源的设定方法光 86&r;c:  
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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[ZWOi\- ;  
    | ~D~#Nz  
    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。 n n8N 9w  
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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。 wE <PXBl\b  
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    图5. 视网膜重点采样规格设定
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    脚本 N~yGtnW  
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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: Tkf4`Gxd  
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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。 '(($dT  
    余下的脚本计算与屈光度有关的所有参数。 9JC8OSjJ  
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    分析 4~:D7",Jn  
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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。 H&ZsMML/%  
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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 n-lDE}K9%B  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. 0jefV*3qpB  
    vr>Rd{dm  
    Dim entity As T_ENTITY %eqL)pC]  
    Dim op As T_OPERATION BA0.B0+"  
    Dim mat As T_MODELMATERIAL }xzbg  
    Dim A As Double (e{pAm  
    Dim pupilDiam As Double 1Yv#4t  
    Dim eID As Long O~g0R6M6e  
    Dim parID As Long nr9c G/"  
    Dim count As Integer ;,_c1x/F  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double {5:V hW}  
    Dim tlens As Double, nlens As Double <~qhy{hRn  
    Dim curv As Double, conic As Double y {1p#  
    Dim ok As Long Ed~2Qr\65  
    *8QGv6*vQ  
    Sub Main kIUb`b>B  
    (svd~he2  
        '用户输入对话框 MU&P+Wr  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 b<rJ@1qtJ  
            TextBox 220,21,40,21,.TextBox1 'default: 0 _\xd]~ELj  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 = l9H]`T/  
            OKButton 40,91,90,21 80ms7 B  
            CancelButton 190,91,90,21 GwVSRI:[N  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 SA$1rqU=  
            TextBox 220,49,40,21,.TextBox2 'default: 4 'xp&)g L  
        End Dialog | [lM2  
        Dim dlg As UserDialog e6?h4}[+*  
    ! =c&U.B  
        ok = Dialog (dlg) gobqS+c  
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        If ok=0 Then    'cancel button was pressed 68LB745  
            Print "Execution cancelled." \uV;UH7qe  
            End &ExYul  
        End If Z-+p+34ytq  
    ztS'Dp}q<  
        'Assign accommodation and pupil diameter & use defaults if field left empty G" Fd]'  
        If dlg.TextBox1 = "" Then GzUgzj|BN~  
            A = 0           'Default accommodation ^m:?6y_uw  
        Else BqKh&m  
            A = CDbl(dlg.TextBox1) \YBY"J  
        End If 8^N"D7{mO  
    4RqOg1  
        If dlg.TextBox2 = "" Then uU]4)Hp  
            pupilDiam = 4   'Default pupil diameter v2Bks 2  
        Else &H{KXX"X  
            pupilDiam = CDbl(dlg.TextBox2) ^25[%aJI  
        End If S|%f<zAtJ  
    }0Q6iHX@  
        Print " " `QlChxd  
        Print "Accommodation = " & A & " Diopters" %h%^i   
        Print "Pupil Diameter = " & pupilDiam & " mm" 8W"~>7/>D  
    ~l@SGHx  
        ' Calculate new parameters with accommodation U:`g12  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness d(L u|/~  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens "+ji`{  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens bgm$<;`U  
    q*<Df=+B  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens H{P"$zj`l  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens s3G3_&  
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        tlens = 3.767 + 0.04*A                  'Lens thickness jn#  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction |:tFQ.Z'2  
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        'Adjust parameters to account for accommodation RCq_FY  
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        '************************************************************************* Ss&R!w9p  
        'Aqueous thickness (Position of Lens) J~:/,'Ea  
        '************************************************************************* 3L4lk8Dd  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) $N=A,S  
        GetCustomElement eID, entity ![iAALPNl  
    ;ePmN|rq;  
        parID = FindFullName( "Geometry.Arizona Eye" ) cV5Lp4wY?  
    t\]CdH`+  
        ' Delete any shift(s) in z SD6xi\8  
        count = 0 It4J \S  
        While GetOperationCount(eID)>count ^6ZA2-f/<8  
            GetOperation eID, count, op n}yqpW!%n  
            If op.Type="ShiftZ" Then ~OEP)c\k  
                DeleteOperation eID,count SN'LUwaMp!  
                count=count-1 +aV>$Y  
            End If 8KW}XG  
            count=count+1 '@Y@H,  
        Wend xUzSS@ot^  
    fdCsn:  
        'Set new shift in Mx-,:a9}  
        op.Type = "ShiftZ" t_WNEZW7f  
        op.val1 = taq 56AaviEC  
        op.parent = parID ){")RrD(  
        AddOperation eID, op ~/h P6*  
        Print "Set aqueous humor thickness = " & taq-0.55 (6?pBdZ  
    @B~/0 9  
        '************************************************************************* w'.ny<Pe  
        'Radius and conic constant of anterior lens !o&Mw:d  
        '************************************************************************* d;(L@9HHD  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) oHbEHS61  
        GetConic eID, entity, curv, conic !w98 [BE7  
    a)[XJLCQ  
        SetConic eID, entity, 1/Rant, CCant gNzQ"W=  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant X1i6CEa<  
    \p.Byso,  
        '************************************************************************* JMOQDo  
        'Radius and conic constant of posterior lens xZL`<3?  
        '************************************************************************* KC? hsID{  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) H4 & d,8:m  
        GetConic eID, entity, curv, conic oyJ/Oe {  
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        SetConic eID, entity, 1/Rpost, CCpost v)+wr[Qs  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 2 ,;+)  
    F)Yn1&a#H  
        '************************************************************************* ^Y ~ ,s  
        'Lens thickness (Position of posterior lens surface) F1)Q#ThF\  
        '************************************************************************* Ab-S*| B  
    T8ZBQ;o  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) iH( K[F /  
    >RBq&'f  
        ' Delete any z-shift(s) Nd#t !=  
        count = 0 Yk:fV&]  
        While GetOperationCount(eID)>count jfS?#;T)  
            GetOperation eID, count, op C_PXh>H]'  
            If op.Type="ShiftZ" Then q[1H=+  
                DeleteOperation eID,count _$wWKJy9  
                count=count-1 m^O:k"+!  
            End If KcfW+> W3  
            count=count+1 @"kA&=0;|J  
        Wend \%E Zg  
    iX.=8 ~3  
        'Set new z-shift RV^2[Gdi  
        op.Type = "ShiftZ" ph30/*8  
        op.val1 = tlens \h :Rw|  
        op.parent = parID %g0"Kj5  
        AddOperation eID, op H[<"DP  
        Print "Set lens thickness = " & tlens {j,bV6X  
    ;MCv  
        '************************************************************************* /pFg<  
        'Lens index of refraction LZM[Wg#  
        '************************************************************************* C\.?3  
        eID = FindMaterial( "Lens" ) FD#?pVyPn^  
        GetModelMaterial eID, mat +sE81B  
    Nb#E +\q  
        mat.Nd = nlens E`iT>+LG<  
        SetModelMaterial eID, mat \H<'W"  
        Print "Set lens index of refraction = " & nlens /zuU  
    "a5?cX;  
        '************************************************************************* ^P:9iu)+]~  
        'Pupil diameter 3l`yy])t  
        '************************************************************************* X||o iqbY  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) vV#Jl) A  
    <3 AkF# C9  
        'Adjust pupil diameter (trimming volume inner hole) /Rx%}~x/m  
    B HoZ}1_  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" F]z xx  
    o,D>7|h  
        ' Adjust pupil location to just in front of the lens g*- K!X6l  
        parID = FindFullName( "Geometry.Arizona Eye" ) ]![ewO@  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) A7+eWg{  
        count = 0 TxN#3m?G  
        While GetOperationCount(eID)>count *ta|,  
            GetOperation eID, count, op JF%+T yMe  
            If op.Type="ShiftZ" Then E} Uy-  
                DeleteOperation eID,count :8E(pq|1PB  
                count=count-1 bW3e*O$V  
            End If 8\. #  
            count=count+1 2p@Rr7  
        Wend  4rwfY<G  
        op.Type = "ShiftZ" /r[0Dw  
        op.val1 = taq-0.01 sUfH1w)0  
        op.parent = parID &UbNp8h  
        AddOperation eID, op ~e~4S~{  
    }n:'@}  
        Print "Set pupil diameter = " & pupilDiam 9!_`HE+(XJ  
    1reJ7b0  
        'Update AZ Eye subassembly Description f*1.Vg0`-  
        eID = FindFullName( "Geometry.Arizona Eye" ) N: d`L+tcc  
        GetEntity eID, entity cEve70MV  
        entity.Description = "Accommodation = " & A & "D" RQ9fA1YP  
        SetEntity eID, entity 2!7wGXm~U  
    @]Iku6d-  
        Update {\;CGoN|  
        Print "DONE!" '2uQ  
         IA$:r@QNx8  
    End Sub .FqbX5\p,  
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    如果屈光度是4,光瞳直径是4,则会输出如下数据: ="d}:Jl  
    d=xU f`^  
    Accommodation = 4 Diopters -zN*2T  
    Pupil Diameter = 4 mm a&.8*|w3  
    Set aqueous humor thickness = 2.81 4@/[aFH  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 BNQ~O^R0  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 y''`73U"  
    Set lens thickness = 3.927 5mnIQ~psR  
    Set lens index of refraction = 1.42672 fg*IHha  
    Set pupil diameter = 4 ojT TYR{  
    DONE! T.`EDluG  
    %^2LTK(P  
    *]W{83rXQ  
    QQ:2987619807 Dx4?6  
     
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