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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 7WV"Wrl]  
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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。 M7DoAS{6e  
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    模型 2Z(?pJyDM  
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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(G{_>>  
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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. p,4S?c r>a  
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    光源 d.snD)X  
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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_IF{%i  
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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。 m7,"M~\pX  
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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。 Y Odwd}M  
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    图2. 字母F光源的设定方法光 .v) A|{:2  
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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 r^d:Po  
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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。 (.M &nN'Ce  
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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。 ;>p{|^X0D  
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    图5. 视网膜重点采样规格设定
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    脚本 0Q/BTT%X  
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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: 7baQ4QY?n  
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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。 NSh~O!pX  
    余下的脚本计算与屈光度有关的所有参数。 "qY_O/Eg]]  
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    分析 Gy[m4n~Z5  
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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。 [M.!7+$o  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 _E[)_yH'-  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. I_h&35^t  
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    Dim entity As T_ENTITY ~LN {5zg  
    Dim op As T_OPERATION uHO>FM,  
    Dim mat As T_MODELMATERIAL 8DJoQl9  
    Dim A As Double |NWo.j>4-  
    Dim pupilDiam As Double jUX0sRDk  
    Dim eID As Long 7pz #%Hf  
    Dim parID As Long }Ias7d?re  
    Dim count As Integer r`CsR0[  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double lxD~[e  
    Dim tlens As Double, nlens As Double k| ,F/:  
    Dim curv As Double, conic As Double g~$cnU  
    Dim ok As Long h>'Mh;+  
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    Sub Main ],ISWb  
    nx'D&, VX  
        '用户输入对话框 .q (1  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 v|u[BmA)*k  
            TextBox 220,21,40,21,.TextBox1 'default: 0 CrI:TB>/ "  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 n[`FoY  
            OKButton 40,91,90,21 9TbRrS09  
            CancelButton 190,91,90,21 .~dNzonq  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 c'~6 1HA<  
            TextBox 220,49,40,21,.TextBox2 'default: 4 uz;z+Bd^  
        End Dialog =?g B@vS  
        Dim dlg As UserDialog 0T7""^'&  
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        ok = Dialog (dlg) S+&Bf ~~D  
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        If ok=0 Then    'cancel button was pressed IX) \z  
            Print "Execution cancelled." P+nd?:cz  
            End uMe]].04  
        End If aaM76;  
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        'Assign accommodation and pupil diameter & use defaults if field left empty ?#P@N4Uw}y  
        If dlg.TextBox1 = "" Then JQ)w/@Vu=  
            A = 0           'Default accommodation S 7 *LV;  
        Else m_g2Cep  
            A = CDbl(dlg.TextBox1) tjTnFP/=  
        End If (7_}UT@w-  
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        If dlg.TextBox2 = "" Then }grel5lq  
            pupilDiam = 4   'Default pupil diameter 0B?t:XU,  
        Else P4S]bPIp  
            pupilDiam = CDbl(dlg.TextBox2) G :JQ_w  
        End If $,9A?'  
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        Print " " iy\ 6e k1  
        Print "Accommodation = " & A & " Diopters" K/Qo~  
        Print "Pupil Diameter = " & pupilDiam & " mm" n6]8W^g  
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        ' Calculate new parameters with accommodation #.^A5`k  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness soXIPf  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens <@z!kl  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ^>ICycJ  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens qlgo#[i  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Yy 3g7!K5E  
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        tlens = 3.767 + 0.04*A                  'Lens thickness dF<GuS;l5  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction \hr2#!  
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        'Adjust parameters to account for accommodation 70BLd(?  
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        '************************************************************************* nA?Ks!9T  
        'Aqueous thickness (Position of Lens) nWz7$O  
        '************************************************************************* $]t3pAI[H0  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) -L&%,%  
        GetCustomElement eID, entity s7> a  
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        parID = FindFullName( "Geometry.Arizona Eye" ) MGU%"7i'}  
    ' V#$PZx  
        ' Delete any shift(s) in z F2:nL`]b[  
        count = 0 'NYW`,  
        While GetOperationCount(eID)>count $4ZjNN@  
            GetOperation eID, count, op *H({q`j33k  
            If op.Type="ShiftZ" Then O-jpS?@  
                DeleteOperation eID,count l1I\khS  
                count=count-1 [;RO=  
            End If O=E?m=FR"  
            count=count+1 Hru~Y}V  
        Wend 0Mu6R=s  
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        'Set new shift in ly~tB LH}  
        op.Type = "ShiftZ" Xdtyer%  
        op.val1 = taq b[s=FH]#N  
        op.parent = parID f~?4  
        AddOperation eID, op f5o##ia7:  
        Print "Set aqueous humor thickness = " & taq-0.55 cy @",z  
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        '************************************************************************* ,?/AIL]_  
        'Radius and conic constant of anterior lens .TpM3b#r  
        '************************************************************************* o<8SiVC2  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) eRm 9LOp  
        GetConic eID, entity, curv, conic yYN_]& ag  
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        SetConic eID, entity, 1/Rant, CCant Pof]9qE-y  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant *1c1XN<7  
    3K{G=WE$  
        '************************************************************************* GA+#'R  
        'Radius and conic constant of posterior lens Yx"un4  
        '************************************************************************* h= Mmd  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 9L7jYy=A#  
        GetConic eID, entity, curv, conic %s* F~E  
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        SetConic eID, entity, 1/Rpost, CCpost "l[ c/q[  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost -ztgirU  
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        '************************************************************************* YG K7b6  
        'Lens thickness (Position of posterior lens surface) h"ZR`?h  
        '************************************************************************* bBg=X}9  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Ce`#J6lT  
    @aY>pr5!  
        ' Delete any z-shift(s) *wp>a?sG\  
        count = 0 VbfTdRD-  
        While GetOperationCount(eID)>count 7;r Jr&.)  
            GetOperation eID, count, op h;DLD8L  
            If op.Type="ShiftZ" Then ,0\P r  
                DeleteOperation eID,count V_"UiN"o  
                count=count-1 + C'<*  
            End If *Eg[@5;QA  
            count=count+1 Q|7l!YTzVu  
        Wend B x-"<^<  
    Zg=jDPt}  
        'Set new z-shift 6BH P#B2j  
        op.Type = "ShiftZ" oxZXY]$y  
        op.val1 = tlens HA`q U  
        op.parent = parID JDP/vNq  
        AddOperation eID, op B0$ge"FK9  
        Print "Set lens thickness = " & tlens 0'zX6%  
    ;GV~MH-F  
        '************************************************************************* Mem1X rBH  
        'Lens index of refraction J u"K"  
        '************************************************************************* ,%d?gi"&  
        eID = FindMaterial( "Lens" ) [DD#YL\P  
        GetModelMaterial eID, mat vR*p1Kq:  
    .!Q*VTW  
        mat.Nd = nlens ( 8Q*NZ  
        SetModelMaterial eID, mat ;/ASl<t,  
        Print "Set lens index of refraction = " & nlens [ ~:wS@%  
    L['g')g.  
        '************************************************************************* 'bn$"A"{o  
        'Pupil diameter ~%?LFR'  
        '************************************************************************* bwyj[:6l  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) BFvRU5&Sz  
    v ocWV/  
        'Adjust pupil diameter (trimming volume inner hole) HyC826~-rI  
    'mYUAVmSC#  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" #u/5 nm  
    FwwOp"[~t  
        ' Adjust pupil location to just in front of the lens g]Z@_  
        parID = FindFullName( "Geometry.Arizona Eye" ) H6Q!~o\"H  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ;5&=I|xqe  
        count = 0 "@(Sw>*o  
        While GetOperationCount(eID)>count +j(7.6ia  
            GetOperation eID, count, op i% n9RuULh  
            If op.Type="ShiftZ" Then xz3|m _)  
                DeleteOperation eID,count bx:j`5Uj`  
                count=count-1 ,w%hD*  
            End If su0q 2.  
            count=count+1 QC<O=<$Q[  
        Wend q!y!=hI  
        op.Type = "ShiftZ" X?++I 4\  
        op.val1 = taq-0.01 L "5;<  
        op.parent = parID tJII-\3"  
        AddOperation eID, op =4#p|OZP  
    (d*~Qpi{7  
        Print "Set pupil diameter = " & pupilDiam 7bYN  
    O&evv8 6L  
        'Update AZ Eye subassembly Description vVf%wei^#  
        eID = FindFullName( "Geometry.Arizona Eye" ) ;( [^+_/  
        GetEntity eID, entity cCv@f ks  
        entity.Description = "Accommodation = " & A & "D" e/R$Sfj]  
        SetEntity eID, entity /3j3'~0  
    )-^[;:B\k"  
        Update z 8<"  
        Print "DONE!" \pVNJ y$`<  
         Dd'J"|jF38  
    End Sub En{< OMg  
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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: }ws(:I^  
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    Accommodation = 4 Diopters ,qwVDYJ  
    Pupil Diameter = 4 mm K$c?:?wmo  
    Set aqueous humor thickness = 2.81 :aR_f`KMm  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 "Bl6 ) qw  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 '}9 %12\^h  
    Set lens thickness = 3.927 h3j`X'  
    Set lens index of refraction = 1.42672 nG~^-c+  
    Set pupil diameter = 4 t/J|<Ooj?  
    DONE! C&f{LpB`  
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    QQ:2987619807 ?0?+~0sI  
     
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