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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 + hMF\@  
    #r80FVwiD  
    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。  W o$UV  
    8"x\kSMb  
    模型 `>{S?t<  
    N|s8PIcSp  
    模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 d/Fy0=0  
    :N:e3$c  
    Table 1. AZ眼睛模型的定义
    O>arCr=H  
    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. @XX7ydG5  
    kX'a*AG  
    光源 ?} U l(  
    2v1dSdX,W  
    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。 \1#!% I=.  
    VI^~I;M^  
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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。 _zFJ]7Ym.)  
    H?dEgubg7]  
    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。 q yYf&VC}  
    vjXCArS  
    图2. 字母F光源的设定方法光 `k'Dm:*`u4  
    ${, !Ll7)  
    图3. 字母F在视网膜上位置点列图
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    视网膜的散射 +P"u1q*+p  
    DBzF\-  
    在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 3a6  
    bn"z&g   
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    图4. 视网膜朗伯散射设定
    M9sB2Ips<  
    注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 ~Uaz;<"j0  
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    图5. 视网膜重点采样规格设定
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    脚本 Q02:qn?T  
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    内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框,如下图所示: fm^)u"  
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    图6. 用户对话框的创建与编辑
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    图7. 用户对话框编辑器
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    如果“OK”按钮按下,将会核对对话框下面的代码行,如果点击取消则脚本终止。然后输入的参数赋予变量,如果此处是保留为空白,则使用默认值。因此,如果没有值输入并点击“OK”按钮,则脚本是以屈光度为0,光瞳直径为4mm来运行的。 =J&aN1Hgt  
    余下的脚本计算与屈光度有关的所有参数。 vpqMKyy  
    -`e`U%n  
    分析 rwep e5  
    E 5bo60z  
    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 3+# "4O  
    z`+j]NX]  
    图7. 字母F在视网膜上颜色分析
    |m>n4 -5QL  
    脚本代码 h2Jdcr#@FF  
    dq$C COC^F  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. r=pb7=M#LN  
    <\5Y~!)  
    Dim entity As T_ENTITY r$.v"Wh)  
    Dim op As T_OPERATION Z8_Q Kw>  
    Dim mat As T_MODELMATERIAL yzmwNsu  
    Dim A As Double Y=N; Bj  
    Dim pupilDiam As Double H>2f M^  
    Dim eID As Long jF%[.n[BU  
    Dim parID As Long ( -rw]=Qu  
    Dim count As Integer lEv<n6:_  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double `` mi9E  
    Dim tlens As Double, nlens As Double ]&/KAk  
    Dim curv As Double, conic As Double ym)`<[T  
    Dim ok As Long .Qeml4(`3  
    9d!}]+"d42  
    Sub Main /!Kl  
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        '用户输入对话框 tpi>$:e  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 kaj6C_k|  
            TextBox 220,21,40,21,.TextBox1 'default: 0 ePJtdKN:  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 g$ oe00b  
            OKButton 40,91,90,21 4?^t=7N  
            CancelButton 190,91,90,21 `L=$ ,7`  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 lhA<wV1-9G  
            TextBox 220,49,40,21,.TextBox2 'default: 4 J]|lCwF  
        End Dialog \aO.LwYm;:  
        Dim dlg As UserDialog q#~]Hp=W5  
    |E)IJj 3  
        ok = Dialog (dlg) (^Kcyag4  
    /RmHG H!  
        If ok=0 Then    'cancel button was pressed h}_1cev?  
            Print "Execution cancelled." h7S&tW GU  
            End /U%Xs}A)  
        End If rn?:utP  
    97um7n  
        'Assign accommodation and pupil diameter & use defaults if field left empty ^f,('0p- >  
        If dlg.TextBox1 = "" Then Q`}n; DV  
            A = 0           'Default accommodation q(yw,]h]{  
        Else K>`7f]?H*e  
            A = CDbl(dlg.TextBox1) #?z 1cgCg  
        End If &n:F])`2  
    7^J-5lY3S  
        If dlg.TextBox2 = "" Then Pl }dA  
            pupilDiam = 4   'Default pupil diameter Vhww-A  
        Else ZK[S'(6q  
            pupilDiam = CDbl(dlg.TextBox2) oIM]  
        End If .#;;pu7W  
    iM Xl}3  
        Print " " a]465FY  
        Print "Accommodation = " & A & " Diopters" M#qZ0JT4  
        Print "Pupil Diameter = " & pupilDiam & " mm" 1& k_&o  
    <'4DMZ-G  
        ' Calculate new parameters with accommodation kgz2/,  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ?~a M<rcZ  
    9 0[gXj  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens I$neE"wW  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens +*Cg2`  
    )]%GNdU  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens yoj5XBM  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens AX%9k  
    &:-`3J-  
        tlens = 3.767 + 0.04*A                  'Lens thickness d%9r"=/  
    [PrR 3 0:  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction id.o )=  
    *Df|D/,WE  
        'Adjust parameters to account for accommodation [j5 ^Zb&0  
    MWCP/~>a2  
        '*************************************************************************  IjDG  
        'Aqueous thickness (Position of Lens) fwIZr~l  
        '************************************************************************* w>X33Ff]8@  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) #TUsi,jG  
        GetCustomElement eID, entity I/GZ  
    N L]:<FG  
        parID = FindFullName( "Geometry.Arizona Eye" ) sf?D4UdIH  
    doxQS ohS  
        ' Delete any shift(s) in z .J~iRhVOF  
        count = 0 CD^_>sya  
        While GetOperationCount(eID)>count )4a&OlEI  
            GetOperation eID, count, op 8*)zoT*A  
            If op.Type="ShiftZ" Then )E^4\3 ^:  
                DeleteOperation eID,count 11 .RG *  
                count=count-1 / GJ"##<  
            End If ?/{ qRz'C<  
            count=count+1 +6f5uMKUvs  
        Wend /+J?Ep(_  
    /PIU@$DV  
        'Set new shift in jjz<V(Sk  
        op.Type = "ShiftZ" g B<p  
        op.val1 = taq B\}E v&  
        op.parent = parID 9\Mesf1$o  
        AddOperation eID, op m7e$ Z  
        Print "Set aqueous humor thickness = " & taq-0.55 gW6lMyiLb  
    d?&?$qf[  
        '************************************************************************* sj`9O-?49  
        'Radius and conic constant of anterior lens \x x<\8Qr_  
        '************************************************************************* c?eV8h1G  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) OR( )D~:n  
        GetConic eID, entity, curv, conic $Kb-mFR  
    i2$U##-ro]  
        SetConic eID, entity, 1/Rant, CCant z0HCmj9T  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant H U$:x"AW  
    S_6`.@B}  
        '************************************************************************* pp#Kb 2*  
        'Radius and conic constant of posterior lens 9))%tYN  
        '************************************************************************* Z[AJat@H  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Ajq;\- :  
        GetConic eID, entity, curv, conic Y.i<7pBt  
    f8N  
        SetConic eID, entity, 1/Rpost, CCpost rEdr8qw  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost QKZm<lUL  
    "a`0s_F,^  
        '************************************************************************* B {/Pv0y   
        'Lens thickness (Position of posterior lens surface) 0wZLkU_(  
        '************************************************************************* `U!eh1*b  
    q&Q* gEFK  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) @OFl^U0/  
    <W/-[ M  
        ' Delete any z-shift(s) YIfPE{,  
        count = 0 @w6^*Z_hQ  
        While GetOperationCount(eID)>count v2EM| Q xp  
            GetOperation eID, count, op u;& `_=p  
            If op.Type="ShiftZ" Then x7Ly,  
                DeleteOperation eID,count =[t([DG  
                count=count-1 \#2,1W@  
            End If WqY:XE+?\  
            count=count+1 J%f5NSSU{6  
        Wend 1(hgSf1WH  
    A~I}[O~(pb  
        'Set new z-shift >|@ /GpD  
        op.Type = "ShiftZ" `z5j  
        op.val1 = tlens ( rZq0*  
        op.parent = parID ?*,N ?s(U  
        AddOperation eID, op ^bL.|vB  
        Print "Set lens thickness = " & tlens )J~Q x-jG  
    l%fnGe` _  
        '************************************************************************* wm*`  
        'Lens index of refraction _4zlEo-.gU  
        '************************************************************************* *M+:GH/5  
        eID = FindMaterial( "Lens" ) Mk|h ><Q"  
        GetModelMaterial eID, mat t ~U&a9&Z  
    r]BB$^@@V  
        mat.Nd = nlens $CL=M  
        SetModelMaterial eID, mat #5G!lbH  
        Print "Set lens index of refraction = " & nlens faD(, H  
    s;8J= \9W  
        '************************************************************************* )dC%g=dtc  
        'Pupil diameter b4ORDU  
        '************************************************************************* U G^6I5  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 6n%^ U2H/-  
    aKH\8O4L5  
        'Adjust pupil diameter (trimming volume inner hole)  >?U (w<  
    oc\rQ?  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" /kx:BoV  
    I7BfA,mZ7  
        ' Adjust pupil location to just in front of the lens 4d0PW#97.  
        parID = FindFullName( "Geometry.Arizona Eye" ) G:u[Lk#6K  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) HewVwD<C  
        count = 0 rm3 ~]  
        While GetOperationCount(eID)>count f} } Bb8  
            GetOperation eID, count, op ]Z<{ ~  
            If op.Type="ShiftZ" Then @] )a  
                DeleteOperation eID,count rCYNdfdpp  
                count=count-1  `9S<E  
            End If .t"s>jq 1  
            count=count+1 us`hR!_  
        Wend 6sQ"go$}  
        op.Type = "ShiftZ" ms;Lu- UR  
        op.val1 = taq-0.01 b LL!iz?  
        op.parent = parID d<7xSRC   
        AddOperation eID, op 6G@_!i*2F  
    7zR 7v  
        Print "Set pupil diameter = " & pupilDiam 3gv>AgG  
    |P5?0{  
        'Update AZ Eye subassembly Description En5I  
        eID = FindFullName( "Geometry.Arizona Eye" ) CzNSJVE5  
        GetEntity eID, entity _6=6 b!hD  
        entity.Description = "Accommodation = " & A & "D" ]7dm`XV  
        SetEntity eID, entity /:yKa=$  
    Pb]s+1  
        Update $`l- cSH;  
        Print "DONE!" "p2PZ)|  
         C+y:<oo)  
    End Sub 8{Zgvqbb  
    c?<FMb3]  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: >K50 h  
    [(#ncR8B  
    Accommodation = 4 Diopters dBobVT'  
    Pupil Diameter = 4 mm |!57Z4X  
    Set aqueous humor thickness = 2.81 !R)v2Mk|  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 ym(r;mj!  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 s`H}NjWx  
    Set lens thickness = 3.927 TmzEZ<} &7  
    Set lens index of refraction = 1.42672 =H!u4  
    Set pupil diameter = 4 I"T_<  
    DONE! #<v3G)|aS  
    uERc\TZ  
    G9Xrwk<g4  
    QQ:2987619807 !Otyu6&  
     
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