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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 @XOi62(  
    r3I,11B  
    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。 2w?G.pO#  
    GH'O! }  
    模型 vW' 5 ` %  
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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。 H?}wl%  
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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. 0 15Owi  
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    光源 ;mO,3dV  
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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。 ,VD6s !(  
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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。 '7nJb6V,0l  
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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。 &]nd!N  
    a'[)9:  
    图2. 字母F光源的设定方法光 L? ;/cO^  
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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 ^now}u9S6  
    }(=ml7)v  
    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。 |vy]8?Ak  
    *1;23BiH-  
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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。 ci7~KewJ*  
    \ j]~>9  
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    图5. 视网膜重点采样规格设定
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    脚本 K<,Y^3]6?  
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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: 0^>E`/  
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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。 v,\93mNp[  
    余下的脚本计算与屈光度有关的所有参数。 R+^zy"~  
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    分析 `9EVB;  
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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。 5}SXYA}  
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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 }9Q f#&o  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. pU[K%@sC  
    #! @m y  
    Dim entity As T_ENTITY N K"%DU<  
    Dim op As T_OPERATION IuWX*b`v  
    Dim mat As T_MODELMATERIAL SbJh(V-pr  
    Dim A As Double F25<+ 1kr  
    Dim pupilDiam As Double 3qcpf:  
    Dim eID As Long 9R:(^8P8  
    Dim parID As Long tD^a5qPh  
    Dim count As Integer (v|`LmV  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 8a!2zwUBV  
    Dim tlens As Double, nlens As Double % 9YA^ri  
    Dim curv As Double, conic As Double u p~@?t2  
    Dim ok As Long MZiF];OY  
    agTK =  
    Sub Main a?\ `  
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        '用户输入对话框 @ YrGyq  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 9>zDJx  
            TextBox 220,21,40,21,.TextBox1 'default: 0 |Qq+8IeYG  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 j5A\y^Kv  
            OKButton 40,91,90,21 Q5T(nEA  
            CancelButton 190,91,90,21 DUPmq!A  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 k^yy$^=<  
            TextBox 220,49,40,21,.TextBox2 'default: 4 SJF2k[da  
        End Dialog (77Dif0)'  
        Dim dlg As UserDialog TQ2i{e  
    %SFw~%@3&~  
        ok = Dialog (dlg) 6<Be#Y]b  
    :!hk~#yvJ9  
        If ok=0 Then    'cancel button was pressed '&{(:,!B  
            Print "Execution cancelled." 9Iy[E,j  
            End l85CJ+rg  
        End If @hBx, `H^  
    MSF Nw  
        'Assign accommodation and pupil diameter & use defaults if field left empty ~CJYQFt  
        If dlg.TextBox1 = "" Then ;p.j  
            A = 0           'Default accommodation @]yQJuXA&Z  
        Else !zl/0o  
            A = CDbl(dlg.TextBox1) q2D`1nT  
        End If <|wmjW/ D  
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        If dlg.TextBox2 = "" Then DvU~%%(0^  
            pupilDiam = 4   'Default pupil diameter r$Kh3EEF`E  
        Else hiT9H5 6 >  
            pupilDiam = CDbl(dlg.TextBox2) @D2`*C9  
        End If (2 mS v  
    bwT"$Ee  
        Print " " %{c2lyw  
        Print "Accommodation = " & A & " Diopters" H?ieNXP7{  
        Print "Pupil Diameter = " & pupilDiam & " mm" 8g&uE*7N  
    l'P[5'.  
        ' Calculate new parameters with accommodation WJP`0f3  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness mfUKHX5  
    >E{#HPpBi  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens V}p*HB@:  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens C3^X1F0  
    $d5&~I  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens X6n|Xq3k  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens $K;_Wf  
    if\k[O 1T6  
        tlens = 3.767 + 0.04*A                  'Lens thickness A/ r;;S)%2  
    T9,lblU Q  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ;o&_:]S  
    ZD iW72&Q  
        'Adjust parameters to account for accommodation !<JG&9ODP  
    R?i-"JhW  
        '************************************************************************* <$Xn:B<H  
        'Aqueous thickness (Position of Lens) ntd ":BKi  
        '************************************************************************* #IcT @(  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) >0[qi1  
        GetCustomElement eID, entity ^2P;CAjj-  
    9$}+-Z  
        parID = FindFullName( "Geometry.Arizona Eye" ) p=je"{  
    (2&K (1.Y  
        ' Delete any shift(s) in z JT}dor  
        count = 0 im_0ur&'  
        While GetOperationCount(eID)>count \["1N-q b  
            GetOperation eID, count, op B]CS2LEqh  
            If op.Type="ShiftZ" Then % DHP  
                DeleteOperation eID,count ;L MEU_  
                count=count-1 .l" _ K  
            End If LK oM\g(  
            count=count+1 Xb8:*Y1'  
        Wend C:TuC5Sr  
    ZnxOa  
        'Set new shift in `3H?*\<(  
        op.Type = "ShiftZ" 7zi^{]  
        op.val1 = taq Ji)a%j1V9  
        op.parent = parID %t(, *;  
        AddOperation eID, op c>%z)uY>/  
        Print "Set aqueous humor thickness = " & taq-0.55 rYP8V >  
    oC;l5v<  
        '************************************************************************* rmAP&Gw I  
        'Radius and conic constant of anterior lens '{1W)X  
        '************************************************************************* gGceK^#  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) >(YPkmH  
        GetConic eID, entity, curv, conic &)/H?S;yN  
    \^^hG5f  
        SetConic eID, entity, 1/Rant, CCant P,LXZ  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant xw/h~:NT  
    O=9VX  
        '************************************************************************* l)2HHu<  
        'Radius and conic constant of posterior lens jn#N7%{Mk  
        '************************************************************************* !F}J+N=}  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 7m@^=w  
        GetConic eID, entity, curv, conic }(hYG"5  
    ~]D \&D9=?  
        SetConic eID, entity, 1/Rpost, CCpost "m\UqQGX  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost b smoLT  
    {{#a%O  
        '************************************************************************* @[Jt~v  
        'Lens thickness (Position of posterior lens surface) dk, I?c &  
        '************************************************************************* QL|:(QM  
    _mq*j^u,j  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) S{r)/ ~/  
    *X =f  
        ' Delete any z-shift(s) a5Acqa  
        count = 0 xaq=?3QOH  
        While GetOperationCount(eID)>count \!4ghev3  
            GetOperation eID, count, op au9Wo<mR  
            If op.Type="ShiftZ" Then &t=>:C$1Y  
                DeleteOperation eID,count J 6d n~nPK  
                count=count-1 Duo#WtC  
            End If D2wgSrY  
            count=count+1 qS[p|*BL  
        Wend cq+M *1;  
    th>yi)m  
        'Set new z-shift >t6'8g"T  
        op.Type = "ShiftZ" \Lh<E5@]  
        op.val1 = tlens 1rzq$,O  
        op.parent = parID ."#jN><t  
        AddOperation eID, op I! eSJTN  
        Print "Set lens thickness = " & tlens U*Q5ff7M6"  
    r~B Qy'  
        '************************************************************************* L)//- k9  
        'Lens index of refraction B}xo|:f!zj  
        '************************************************************************* gQcr'[[a  
        eID = FindMaterial( "Lens" ) DF&jZ[##  
        GetModelMaterial eID, mat :e9jK[)h0  
    O|g!Y(  
        mat.Nd = nlens 7=ga_2  
        SetModelMaterial eID, mat RAkFgC~  
        Print "Set lens index of refraction = " & nlens do?n /<@o  
    <raqp Oo&  
        '************************************************************************* t>=y7n&q  
        'Pupil diameter HjY-b*B  
        '************************************************************************* :+V1682u  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) g>oYEFFJ  
    5Vm}<8{  
        'Adjust pupil diameter (trimming volume inner hole) +cOI`4`$  
    :DF4g=  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" nO7o7bc  
    u5)A+.v  
        ' Adjust pupil location to just in front of the lens aw@Aoq  
        parID = FindFullName( "Geometry.Arizona Eye" ) 4lKbw4[a  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) "5DAGMU  
        count = 0 Q Fqv,B\<  
        While GetOperationCount(eID)>count :?XHZ  
            GetOperation eID, count, op V6!73 iY  
            If op.Type="ShiftZ" Then 0FR%<u  
                DeleteOperation eID,count e~~k}2~  
                count=count-1 s&_O2(l  
            End If *9:6t6x  
            count=count+1 %T*+t"\)  
        Wend HyYQQ  
        op.Type = "ShiftZ" L$kAe1 V^m  
        op.val1 = taq-0.01 =y(YMWGS  
        op.parent = parID Ch!Q?4  
        AddOperation eID, op KI QBY!N+  
    }8]uZ)[p=  
        Print "Set pupil diameter = " & pupilDiam (C_o^_I:  
    h sw My  
        'Update AZ Eye subassembly Description (cew:z H  
        eID = FindFullName( "Geometry.Arizona Eye" ) (tz]!Aa{s  
        GetEntity eID, entity #CP, \G  
        entity.Description = "Accommodation = " & A & "D" Wjk;"_"gd  
        SetEntity eID, entity F`}w0=-*(  
    umrI4.1c  
        Update s!!t  
        Print "DONE!" p. ~jo  
         E4@fP] R+  
    End Sub ;p"XCLHl  
    BW\5RIWwE5  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: ;= @-j@?  
    ;{7lc9uRj  
    Accommodation = 4 Diopters j/ IZm)\  
    Pupil Diameter = 4 mm zLK ~i>aW  
    Set aqueous humor thickness = 2.81 m95$V&  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 toZI.cSg4  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 3E@&wpj  
    Set lens thickness = 3.927 &rWJg6/  
    Set lens index of refraction = 1.42672 nt`l6b  
    Set pupil diameter = 4 T.dO0$,Q@$  
    DONE! Kd1\D!#!6  
    )Bvu[r Uy  
    !D5`8   
    QQ:2987619807 E4ee_`p  
     
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