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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 "3?:,$*  
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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。 9O:-q[K**  
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    模型 "l6Ob  
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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。 ` h1>rP  
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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. #YLI"/Kn  
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    光源 zM'2opiUY  
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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。 x ~@%+d  
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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。 (m=F  
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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。 6^nxw>-   
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    图2. 字母F光源的设定方法光 4[K6ZDBU  
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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 TK%MVLTK  
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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。 Il<ezD{  
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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。 0 oHnam  
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    图5. 视网膜重点采样规格设定
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    脚本 0bR})}a+Yg  
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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:  <:`x> _  
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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。 >)iCKx  
    余下的脚本计算与屈光度有关的所有参数。 dn= g!=  
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    分析 GvD{I;  
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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。 wqf^n-Ze  
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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 {K+]^M  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. wLH[rwPr  
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    Dim entity As T_ENTITY q|wwfPez7  
    Dim op As T_OPERATION G+f@m,  
    Dim mat As T_MODELMATERIAL qi-!iT(fe  
    Dim A As Double ,;-55|o\V  
    Dim pupilDiam As Double 9\W }p\c  
    Dim eID As Long l+i9)Fc<i  
    Dim parID As Long {afR?3GK  
    Dim count As Integer 0p' =Vel{}  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double L&SlUXyt.c  
    Dim tlens As Double, nlens As Double L;k9}HWpP  
    Dim curv As Double, conic As Double ?3:xR_VWZu  
    Dim ok As Long - +=+W  
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    Sub Main /I3>u  
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        '用户输入对话框 &B5@\Hd;  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 9hIcnPu  
            TextBox 220,21,40,21,.TextBox1 'default: 0 `l8^n0-  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ,V2,FoJ 9  
            OKButton 40,91,90,21 rZv5>aEI  
            CancelButton 190,91,90,21 ! FVXNl  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 m;d#*}n\p  
            TextBox 220,49,40,21,.TextBox2 'default: 4 []rg'9B2b  
        End Dialog F2$Z4%x#  
        Dim dlg As UserDialog Ad:)5R o  
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        ok = Dialog (dlg) Q+UqLass  
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        If ok=0 Then    'cancel button was pressed 2qD80W<1  
            Print "Execution cancelled." P I0[  
            End _A%8oY S  
        End If 4^mpQ.]lO  
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        'Assign accommodation and pupil diameter & use defaults if field left empty A12#v,  
        If dlg.TextBox1 = "" Then GCTf/V\#  
            A = 0           'Default accommodation v&GBu  
        Else |tU4(hC  
            A = CDbl(dlg.TextBox1) HXTZ`'Rv  
        End If 7#BpGQJQ  
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        If dlg.TextBox2 = "" Then \Q+<G-Kb.  
            pupilDiam = 4   'Default pupil diameter D20n'>ddg  
        Else <ZV !fn  
            pupilDiam = CDbl(dlg.TextBox2) P]4C/UDS-~  
        End If P+Ta|-  
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        Print " "  OBCRZ   
        Print "Accommodation = " & A & " Diopters" v~N8H+! d  
        Print "Pupil Diameter = " & pupilDiam & " mm" M#Vl{ b  
    ` qqUuFMM  
        ' Calculate new parameters with accommodation k]=Yi;  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness @,RrAL }|  
    'K=n}}&:  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens OJUH".o  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens \i-HECc"U  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ?>V4pgGCE  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Ih]'OaE   
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        tlens = 3.767 + 0.04*A                  'Lens thickness 8Ilg[Drj*  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction -$#'  
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        'Adjust parameters to account for accommodation 9I:H=5c  
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        '************************************************************************* >900O4  
        'Aqueous thickness (Position of Lens) )/u?_)b4"  
        '************************************************************************* *t'q n   
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ZlHN-!OZp  
        GetCustomElement eID, entity p2;-*D  
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        parID = FindFullName( "Geometry.Arizona Eye" ) fD#VI   
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        ' Delete any shift(s) in z p-H q\DP  
        count = 0 _N5$>2  
        While GetOperationCount(eID)>count !Qu)JR  
            GetOperation eID, count, op QQ4  &,d  
            If op.Type="ShiftZ" Then C< GS._V&  
                DeleteOperation eID,count e 'I13)  
                count=count-1  opK=Z  
            End If + j._NRXRH  
            count=count+1 Q Fv"!Ql  
        Wend 1'dL8Y  
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        'Set new shift in UC)-Fd  
        op.Type = "ShiftZ" iol.RszlZ|  
        op.val1 = taq kETu@la}  
        op.parent = parID 0^VA,QkQ\  
        AddOperation eID, op $0C1';=^}  
        Print "Set aqueous humor thickness = " & taq-0.55 <!#6c :(Q  
    ^[{\ZX  
        '************************************************************************* /`YHPeXu  
        'Radius and conic constant of anterior lens ^ 1rw\Zp  
        '************************************************************************* >qjQ;z[  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Zk*/~f|\  
        GetConic eID, entity, curv, conic IG?044Y  
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        SetConic eID, entity, 1/Rant, CCant '"{ IV  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant tkBp?Wl  
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        '************************************************************************* d^"<Tz!  
        'Radius and conic constant of posterior lens iq>PN:mr  
        '************************************************************************* z\Vu`Y z  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) tH0=ysf  
        GetConic eID, entity, curv, conic "oX@Z^  
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        SetConic eID, entity, 1/Rpost, CCpost aZGX`;3  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost &u-H/C U%  
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        '************************************************************************* <4,n6$E  
        'Lens thickness (Position of posterior lens surface) {FO>^~>l  
        '************************************************************************* iV5x-G`  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) nmlQ-V-  
    \'I->O]  
        ' Delete any z-shift(s) lg_X|yhL  
        count = 0 tSK{Abw1B  
        While GetOperationCount(eID)>count =vx iqRm  
            GetOperation eID, count, op IP'gN-#i  
            If op.Type="ShiftZ" Then ", b}-B  
                DeleteOperation eID,count Fj<#*2{]B  
                count=count-1 [m7^Euury  
            End If f)x^s$H  
            count=count+1 *rPUVhD_  
        Wend 'ojI_%9<  
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        'Set new z-shift :*V1jp+  
        op.Type = "ShiftZ" t0XM#9L  
        op.val1 = tlens 2 fp\s5%J}  
        op.parent = parID y#HDJ=2  
        AddOperation eID, op V3O<l}ak  
        Print "Set lens thickness = " & tlens sr!m   
    d&n&_>  
        '************************************************************************* b_xn80O  
        'Lens index of refraction Vt-D8J\A 0  
        '************************************************************************* )En*5-1  
        eID = FindMaterial( "Lens" ) YNCQPN\v`1  
        GetModelMaterial eID, mat 5tMp@$F\{[  
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        mat.Nd = nlens 6]#pPk8[Z  
        SetModelMaterial eID, mat >]?!c5=  
        Print "Set lens index of refraction = " & nlens T0xU}  
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        '************************************************************************* M&Aeh8>uX  
        'Pupil diameter yrO \\No#H  
        '************************************************************************* '1]Iu@?  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) fI@4 v\  
    =ja(;uC  
        'Adjust pupil diameter (trimming volume inner hole) Id3i qAL  
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        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" X PnN"Y"y  
    4%/iu)nx  
        ' Adjust pupil location to just in front of the lens /*DC`,q  
        parID = FindFullName( "Geometry.Arizona Eye" ) Tl9KL%9  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) q1QrtJFPG  
        count = 0 K@u\^6419  
        While GetOperationCount(eID)>count dx{ZG'@aH  
            GetOperation eID, count, op :=u Ku'~  
            If op.Type="ShiftZ" Then Qzbelt@Wx  
                DeleteOperation eID,count KTX;x2r  
                count=count-1 >(Mu9ie*`  
            End If )*_4=-8H  
            count=count+1 ).HYW _Yih  
        Wend T\\Q!pY  
        op.Type = "ShiftZ" 3#7D g't  
        op.val1 = taq-0.01 X!r9  
        op.parent = parID Tdvw7I-q  
        AddOperation eID, op G%N3h'zDi  
    e >W}3H5w0  
        Print "Set pupil diameter = " & pupilDiam u\gPx4]4c  
    n DLr17  
        'Update AZ Eye subassembly Description =bm<>h7.)  
        eID = FindFullName( "Geometry.Arizona Eye" ) }{<@wE%s  
        GetEntity eID, entity alM ^ X  
        entity.Description = "Accommodation = " & A & "D" $agd9z,&m  
        SetEntity eID, entity -s Iji)t  
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        Update ptXCM[Z+  
        Print "DONE!" yj!4L&A  
         S`ms[^-q*  
    End Sub #SiOx/  
    'Dl31w%:  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: $7%e|0jC  
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    Accommodation = 4 Diopters PS ,@ \  
    Pupil Diameter = 4 mm )LESdX  
    Set aqueous humor thickness = 2.81 !o A,^4(  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 P)h e3  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 tjw4.L<r  
    Set lens thickness = 3.927 G?\\k[#,&  
    Set lens index of refraction = 1.42672 F)x^AJi e  
    Set pupil diameter = 4 bL>J0LWQ  
    DONE! =1' / ?  
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    [43:E*\$  
    QQ:2987619807 >q{E9.~b  
     
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