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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 K/A*<<r ~  
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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。 hZh9uI7.  
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    模型 fNb`X  
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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。 3BB%Z 6F  
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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. )_mr! z(S  
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    光源 Qi_>Mg`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。 #k_HN}B  
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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。 Q>/C*@  
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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。 zXv3:uRp.  
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    图2. 字母F光源的设定方法光 bA\<.d  
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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 6fd+Q  /  
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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。 vJ\pR~?  
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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。 >tO`r.5u9  
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    图5. 视网膜重点采样规格设定
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    脚本 |;.o8}  
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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: *g y{]  
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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。 ]xX$<@HR  
    余下的脚本计算与屈光度有关的所有参数。 (>`5z(X  
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    分析 X5X?&* %{  
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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。 9AxCiT.  
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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 R  zf  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. ?T>'j mmV=  
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    Dim entity As T_ENTITY @O@GRq&V  
    Dim op As T_OPERATION 3 n'V\H vz  
    Dim mat As T_MODELMATERIAL 0PU8 #2pR  
    Dim A As Double AtF3%Z v2  
    Dim pupilDiam As Double ,z;ky5Ct  
    Dim eID As Long aYuD>rD  
    Dim parID As Long zX0md x<|<  
    Dim count As Integer ^ <Pq,u%k  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ,0E{h}(  
    Dim tlens As Double, nlens As Double 'XzXZJ[uq  
    Dim curv As Double, conic As Double 4m*M,#mV  
    Dim ok As Long d?:=PH  
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    Sub Main :um|nRwy9  
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        '用户输入对话框 G:pEE:W[  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 W D T]!  
            TextBox 220,21,40,21,.TextBox1 'default: 0 :WSDf VX  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 tID%}Zv  
            OKButton 40,91,90,21 u%]shm  
            CancelButton 190,91,90,21 c)A{p  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 HsnLm67'  
            TextBox 220,49,40,21,.TextBox2 'default: 4 1gmt2>#v%  
        End Dialog rg{9UVj  
        Dim dlg As UserDialog ={5#fgK>  
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        ok = Dialog (dlg) %H]lGN)  
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        If ok=0 Then    'cancel button was pressed vfl5Mx4  
            Print "Execution cancelled." 6_d.Yfbq  
            End e.@uhB.  
        End If 7UL qo>j  
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        'Assign accommodation and pupil diameter & use defaults if field left empty Ux#x#N  
        If dlg.TextBox1 = "" Then e|&6$A>4]  
            A = 0           'Default accommodation ?V}j`r8|\4  
        Else zGc: @z  
            A = CDbl(dlg.TextBox1) 4#5:~M }  
        End If jL^](J>  
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        If dlg.TextBox2 = "" Then m}8[#:  
            pupilDiam = 4   'Default pupil diameter 0TmR/uUT  
        Else Q}!mx7b0]  
            pupilDiam = CDbl(dlg.TextBox2) ?W0)nQU  
        End If &BtK($  
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        Print " " !!4Qj  
        Print "Accommodation = " & A & " Diopters" Kh4$ wwn  
        Print "Pupil Diameter = " & pupilDiam & " mm" (`6T&>(4  
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        ' Calculate new parameters with accommodation zfc3)7  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness "Vr[4&`  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens 0b/WpP  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens &f7fK|}  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens _=q! BW  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens QT9n,lX  
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        tlens = 3.767 + 0.04*A                  'Lens thickness v3GwD0 0  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction kN%MP 6?J  
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        'Adjust parameters to account for accommodation "wlt> SU  
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        '************************************************************************* yA)(*PFz  
        'Aqueous thickness (Position of Lens) >yXN,5d[  
        '*************************************************************************  .AYj'Y  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) qim 'dp:  
        GetCustomElement eID, entity =1P6Vk  
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        parID = FindFullName( "Geometry.Arizona Eye" ) kPQtQh]y%  
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        ' Delete any shift(s) in z 4GR!y)  
        count = 0 8/t$d#xHI  
        While GetOperationCount(eID)>count +rIL|c}J  
            GetOperation eID, count, op 1Nu1BLPm  
            If op.Type="ShiftZ" Then 5OO'v07b  
                DeleteOperation eID,count T \CCF  
                count=count-1 +4\U)Z/\  
            End If S}f?.7  
            count=count+1 DAwqo.m  
        Wend s;1]tD  
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        'Set new shift in xr7+$:>a  
        op.Type = "ShiftZ" DfV~!bY  
        op.val1 = taq Dw7vv]+ S  
        op.parent = parID ,v&L:a  
        AddOperation eID, op hoT/KWD,  
        Print "Set aqueous humor thickness = " & taq-0.55 /t6X(*xoy  
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        '************************************************************************* +dBz`W D  
        'Radius and conic constant of anterior lens Z4){ 7|~a  
        '************************************************************************* DI`%zLDcY  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) saU]`w_Z*  
        GetConic eID, entity, curv, conic lCF `*DM#  
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        SetConic eID, entity, 1/Rant, CCant ^'p|!`:  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant +[J/Zw0{  
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        '************************************************************************* Qu< Bu)`  
        'Radius and conic constant of posterior lens aF|d^  
        '************************************************************************* <xJ/y|{  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) )HD`O~M>  
        GetConic eID, entity, curv, conic M7>(hVEAW'  
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        SetConic eID, entity, 1/Rpost, CCpost *_ +7ni  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost )RYG%  
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        '************************************************************************* ~^ ^ NHq  
        'Lens thickness (Position of posterior lens surface) c9j*n;Q  
        '************************************************************************* uY< H#k  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) s4%(>Q  
    \([WH!7  
        ' Delete any z-shift(s) b dJ+@r  
        count = 0 \<vNVz7.D  
        While GetOperationCount(eID)>count v(l eide  
            GetOperation eID, count, op YpUp@/"  
            If op.Type="ShiftZ" Then ]NhS=3*i+  
                DeleteOperation eID,count VD4C::J  
                count=count-1 ;WT{|z  
            End If H0a/(4/xg  
            count=count+1 i)Lp7m z  
        Wend j5 Un1  
    7([h4bg{  
        'Set new z-shift 55t\Bms{  
        op.Type = "ShiftZ" eQO#Qso]  
        op.val1 = tlens #'OaKt?Z)  
        op.parent = parID #a| L3zR5v  
        AddOperation eID, op Gg\G'QU  
        Print "Set lens thickness = " & tlens Q,Z*8FH=  
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        '************************************************************************* M}DH5H"s  
        'Lens index of refraction ha;l(U>  
        '************************************************************************* AGYm';z3  
        eID = FindMaterial( "Lens" ) vRA',(](  
        GetModelMaterial eID, mat tvX>{-M  
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        mat.Nd = nlens U,1AfzlF  
        SetModelMaterial eID, mat ,pK| SL  
        Print "Set lens index of refraction = " & nlens I\\QS.2  
    5&CDHc7Oj  
        '************************************************************************* _SZ5P>GIU  
        'Pupil diameter ]WJfgN4  
        '************************************************************************* /?"8-0d  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) lH|LdlX  
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        'Adjust pupil diameter (trimming volume inner hole) RV-hIdAU  
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        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 8_uzpeRhJc  
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        ' Adjust pupil location to just in front of the lens \'19BAm'  
        parID = FindFullName( "Geometry.Arizona Eye" ) *.f2VQ~H  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) r)1Z(tl  
        count = 0 |!d"*.Q@F  
        While GetOperationCount(eID)>count YEYY}/YX  
            GetOperation eID, count, op A%Z)wz{  
            If op.Type="ShiftZ" Then h5|.Et  
                DeleteOperation eID,count -%IcYzyA  
                count=count-1 yy2Ie  
            End If <XQ.A3SG!  
            count=count+1 Gie@JX  
        Wend XeUC0K[D  
        op.Type = "ShiftZ" ]*%+H|l  
        op.val1 = taq-0.01 Em13dem  
        op.parent = parID t~K%.|'0  
        AddOperation eID, op K.>wQA&  
    ;n#%G^!H  
        Print "Set pupil diameter = " & pupilDiam a0Oe:]mo\  
    E@QA".  
        'Update AZ Eye subassembly Description [JTto!Ih$  
        eID = FindFullName( "Geometry.Arizona Eye" ) Zu<]bv  
        GetEntity eID, entity w,.qCpT$_  
        entity.Description = "Accommodation = " & A & "D" O>DNC-m)i{  
        SetEntity eID, entity E\)eu1Hw4B  
    /k:$l9C[  
        Update ~el-*=<m  
        Print "DONE!" =N.!k Vkl  
         qFR dg V>8  
    End Sub ?~ULIO'  
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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: &hZwZgV +3  
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    Accommodation = 4 Diopters ,8K'F  
    Pupil Diameter = 4 mm oJ;rc{n-  
    Set aqueous humor thickness = 2.81 1]4^V7y  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 ;q#]-^  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 T|'&K:[TJ  
    Set lens thickness = 3.927 gb-{2p>}  
    Set lens index of refraction = 1.42672 gp< =Gmd  
    Set pupil diameter = 4 Wr|G:(kw\!  
    DONE! J?712=9  
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    QQ:2987619807 E[Bo4?s&^  
     
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