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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 O.40^u~  
    +Muia5G  
    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。 6[Pr<4J  
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    模型 ` a<|CcUGU  
    MdTd$ 4J3  
    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。 V44sNi  
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    Table 1. AZ眼睛模型的定义
    `a1R "A  
    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. gV.Pg[[1  
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    光源 fB ,!|u  
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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。 |(8Hk@\CT>  
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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。 >A@D;vx  
    0Ukl#6  
    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。 b+#~N>|  
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    图2. 字母F光源的设定方法光 a_fW {;}[  
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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 /v ;Kb|e  
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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。  ,8 NEnB  
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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。 /WgWe  
    2]3Jb{8FI>  
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    图5. 视网膜重点采样规格设定
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    脚本 5 nIlG  
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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: o 0 #]EMr  
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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。 I\6<)2j/L  
    余下的脚本计算与屈光度有关的所有参数。 G+^$JN=  
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    分析 Z!l!3(<G.f  
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    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 e(% Solkm?  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 /+U)!$zm*  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. ,ST.pu8N.  
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    Dim entity As T_ENTITY )P+GklI{4  
    Dim op As T_OPERATION *pUV-^uo  
    Dim mat As T_MODELMATERIAL +( (31l  
    Dim A As Double =9@yJ9c-  
    Dim pupilDiam As Double "fJ|DE&@<i  
    Dim eID As Long AFUl   
    Dim parID As Long 5VoiDM=\c  
    Dim count As Integer A+E@OOw*~  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double . TS=[WGMS  
    Dim tlens As Double, nlens As Double ]+7c1MB(5  
    Dim curv As Double, conic As Double zFQkUgb  
    Dim ok As Long ;@s~t:u  
    !T(Omve)  
    Sub Main <5vB{)Tq  
    ]7 mSM  
        '用户输入对话框 M:f=JuAx  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 80>!qG  
            TextBox 220,21,40,21,.TextBox1 'default: 0 * %BI*p  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 R*C+Yk)Tkt  
            OKButton 40,91,90,21 " CoR?[,x  
            CancelButton 190,91,90,21 5FKd{V'  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 g}KZL-p4\m  
            TextBox 220,49,40,21,.TextBox2 'default: 4 xmx;tq  
        End Dialog g$LwXfg  
        Dim dlg As UserDialog @ &yj7-]  
    ' uw&f;/E  
        ok = Dialog (dlg) TBT*j&!L  
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        If ok=0 Then    'cancel button was pressed vBnHG-5;P  
            Print "Execution cancelled." 5)<jPyC  
            End ?M(Wx  
        End If HNT8~s.2  
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        'Assign accommodation and pupil diameter & use defaults if field left empty Rx-i.EtZ  
        If dlg.TextBox1 = "" Then ~riw7"  
            A = 0           'Default accommodation mj|9x1U)  
        Else cLP @0`^H  
            A = CDbl(dlg.TextBox1) #_\~Vrf(#  
        End If @1Lc`;Wd  
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        If dlg.TextBox2 = "" Then LdUpVO8)l  
            pupilDiam = 4   'Default pupil diameter XLxr~Yo  
        Else ^SCWT\E  
            pupilDiam = CDbl(dlg.TextBox2) RVx<2,['  
        End If rM |RGe  
    Z+7S,M  
        Print " " #::vMnT  
        Print "Accommodation = " & A & " Diopters" *^_!W'T{j  
        Print "Pupil Diameter = " & pupilDiam & " mm" zy;w07-)  
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        ' Calculate new parameters with accommodation J< M;vB)  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness #Qd3A  
    0n=E.qZ9c  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens "FS.&&1(  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens {NDP}UATw  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens >YhqL62!a  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens s&</zU'  
    `_i-BdW  
        tlens = 3.767 + 0.04*A                  'Lens thickness `<d>C}9  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction =p6xc}N  
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        'Adjust parameters to account for accommodation &pz8vWCk  
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        '************************************************************************* Wz]S+IpY  
        'Aqueous thickness (Position of Lens) .5xM7,  
        '************************************************************************* ]"6<"1)  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) bHnQLJ  
        GetCustomElement eID, entity IIZsN*^  
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        parID = FindFullName( "Geometry.Arizona Eye" ) YSif`W!  
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        ' Delete any shift(s) in z i|mA/ e3b  
        count = 0 9A!qg<  
        While GetOperationCount(eID)>count T-TH. R  
            GetOperation eID, count, op %?jf.p*kY  
            If op.Type="ShiftZ" Then GZo4uwG@a  
                DeleteOperation eID,count p%-9T>og  
                count=count-1 }^q#0`e(y  
            End If }d(6N&;"zN  
            count=count+1 VUb*,/hxa  
        Wend %ZK}y{u\  
    *gn*S3Is[j  
        'Set new shift in .$iIr:Tc>  
        op.Type = "ShiftZ" x?IT#ty  
        op.val1 = taq tDo0Q/`  
        op.parent = parID f/ZE_MN2  
        AddOperation eID, op KX`,7-  
        Print "Set aqueous humor thickness = " & taq-0.55 w6_}] &F  
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        '************************************************************************* `upNP/,  
        'Radius and conic constant of anterior lens b}:Z(L,\  
        '************************************************************************* |=POV]K  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ./d (@@  
        GetConic eID, entity, curv, conic YaU A}0cW  
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        SetConic eID, entity, 1/Rant, CCant zBbTj IFQ  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant LHb{9x  
    @j6D#./7j  
        '************************************************************************* hd\#Vh(H  
        'Radius and conic constant of posterior lens ?6dtvz;K+?  
        '************************************************************************* $gNCS:VG*  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) LsXYvX  
        GetConic eID, entity, curv, conic dQ[lXV[}v  
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        SetConic eID, entity, 1/Rpost, CCpost <_![~n$H  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost EB#z\  
    Lj H];=R  
        '************************************************************************* "{k3~epYaN  
        'Lens thickness (Position of posterior lens surface) P*SXfb"HC  
        '************************************************************************* :.cX3dP@  
    /2:r}O  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) o;.-I[9h]  
    JI&>w-~D  
        ' Delete any z-shift(s) vl<J-+|0C  
        count = 0 g:Dg?_o  
        While GetOperationCount(eID)>count $sJn: 8z  
            GetOperation eID, count, op &a`-NRU#  
            If op.Type="ShiftZ" Then ?,j:Y0l.L  
                DeleteOperation eID,count dZW:Cf 9K  
                count=count-1 89paR[  
            End If {x8`gP\H  
            count=count+1 MPt7 /  
        Wend (GQy"IuFh  
    b%kh:NV{S  
        'Set new z-shift +3C S3fTq  
        op.Type = "ShiftZ" L6a8%%`  
        op.val1 = tlens Y%faf.$/9  
        op.parent = parID 1pV"< ,t  
        AddOperation eID, op C$bK!]a  
        Print "Set lens thickness = " & tlens DB0xIP~i,?  
    /Yh8r1^2tZ  
        '************************************************************************* Ur`v*LT}~  
        'Lens index of refraction ;Gi w7a)  
        '************************************************************************* ^{s)`j'I*  
        eID = FindMaterial( "Lens" ) ^Z*_@A_v  
        GetModelMaterial eID, mat B$bsh.  
    v% 1#y5  
        mat.Nd = nlens ]HRZ9oP  
        SetModelMaterial eID, mat ; H3kb +  
        Print "Set lens index of refraction = " & nlens '/j`j>'!^  
    :* 'i\  
        '************************************************************************* C?O{l%0  
        'Pupil diameter <ygO?m{  
        '************************************************************************* mK4a5H  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) <ESAoY"RPN  
    >eC^]#c  
        'Adjust pupil diameter (trimming volume inner hole) F JzjS;  
    @.})nU  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" dw&Xg_$  
    TX>;2S3q   
        ' Adjust pupil location to just in front of the lens F4}Zl  
        parID = FindFullName( "Geometry.Arizona Eye" ) 9$_}E`  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) p;@PfhEz)  
        count = 0 s#Le`pGoW  
        While GetOperationCount(eID)>count T>c;q%A/  
            GetOperation eID, count, op yqK82z5U*R  
            If op.Type="ShiftZ" Then @ +7'0[y?  
                DeleteOperation eID,count %=]{~5f>  
                count=count-1 1t)6wk N  
            End If >$?Z&7Lv  
            count=count+1 rdK.*oT  
        Wend EU+sTe>  
        op.Type = "ShiftZ" -B_dE-l,  
        op.val1 = taq-0.01 PH]q#/'  
        op.parent = parID .VUZ4e  
        AddOperation eID, op qb! vI3  
    GL/\uq  
        Print "Set pupil diameter = " & pupilDiam H(pOR< `  
    +@!9&5S A  
        'Update AZ Eye subassembly Description SQeQ"k|P%  
        eID = FindFullName( "Geometry.Arizona Eye" ) i->sw#  
        GetEntity eID, entity J@Li*Ypo  
        entity.Description = "Accommodation = " & A & "D" g~cWBr%>  
        SetEntity eID, entity ht1 jrCe  
    _ pJU~8  
        Update 83 S],L  
        Print "DONE!" TWn7&,N  
         Z?GC+hG`  
    End Sub %(NRH?  
    3Mdg&~85  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: 9u:MF0:W  
    (s9?#t6  
    Accommodation = 4 Diopters )ow3Bl8w  
    Pupil Diameter = 4 mm H fRxgA@  
    Set aqueous humor thickness = 2.81 &o?pZ(\C  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 _-D(N/  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 5X  
    Set lens thickness = 3.927 .D7\Hao  
    Set lens index of refraction = 1.42672 /O8'8sL5  
    Set pupil diameter = 4 7Fq|Zc`P  
    DONE! *kDXx&7B$  
    D.HAp+lx  
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