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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 z;U LQ  
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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。 P&,hiGTDi  
    yB=C5-\F  
    模型 ^g70AqUc  
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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。 <sO?ev[  
    //~POm  
    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. y-%nJD$  
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    光源 (rAiDRQ[  
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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。 lfXH7jL2~  
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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。 >'eB2  
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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。 S^|$23}  
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    图2. 字母F光源的设定方法光 /3OC7!~;fM  
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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 7U&5^s )J  
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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。 fS5GICx8R  
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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。 3w t:5 Im  
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    图5. 视网膜重点采样规格设定
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    脚本 K5 5} Wi  
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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: i:V0fBR[>  
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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。 gsLr=  
    余下的脚本计算与屈光度有关的所有参数。 ?H y%ULk  
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    分析 \Y51KB\  
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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。 "Q3PC!7X:5  
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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 3DxZ#/!  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. <I>%m,  
    ` %FIgE^  
    Dim entity As T_ENTITY xIS\4]F?r  
    Dim op As T_OPERATION Ix*BI9E  
    Dim mat As T_MODELMATERIAL vh<]aiY  
    Dim A As Double "V*kOb&'*Z  
    Dim pupilDiam As Double ATKYjhc _  
    Dim eID As Long 4$0jz'  
    Dim parID As Long jz|Wj  
    Dim count As Integer [54@irH  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double v(qV\:s}m  
    Dim tlens As Double, nlens As Double 66I|0_  
    Dim curv As Double, conic As Double i0,%}{`  
    Dim ok As Long Rf)'HT  
    *Gg1h@&  
    Sub Main KU1+<OCh  
    zkjPLeX  
        '用户输入对话框 eNI kiJ$uS  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 GCcwEl!K^  
            TextBox 220,21,40,21,.TextBox1 'default: 0 ?R|fS*e2EB  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 X)`(nj  
            OKButton 40,91,90,21 |HaU3E*R  
            CancelButton 190,91,90,21 4 ?9soc  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 *4(/t$)pEl  
            TextBox 220,49,40,21,.TextBox2 'default: 4 DZHrR:q?e  
        End Dialog 9F2P(aS  
        Dim dlg As UserDialog :NwMb^>  
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        ok = Dialog (dlg) el <<D  
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        If ok=0 Then    'cancel button was pressed K$MJ#Zx^  
            Print "Execution cancelled." 5;3c<  
            End N&0uXrw  
        End If jOoIF/So  
    ,omp F$%  
        'Assign accommodation and pupil diameter & use defaults if field left empty g5kYyE  
        If dlg.TextBox1 = "" Then MZUF! B  
            A = 0           'Default accommodation d8Q_6(Ar|  
        Else $\YLmG  
            A = CDbl(dlg.TextBox1) GibggOj2Q,  
        End If ~pd1 )  
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        If dlg.TextBox2 = "" Then jMz1s%C  
            pupilDiam = 4   'Default pupil diameter )8 "EI-/.  
        Else Sb:zN'U  
            pupilDiam = CDbl(dlg.TextBox2) QrNL7{  
        End If &;6|nl9;  
    r 85Xa'hh  
        Print " " YLA557~  
        Print "Accommodation = " & A & " Diopters" %=NM_5a}]  
        Print "Pupil Diameter = " & pupilDiam & " mm" |xsV(jK8  
    )Dk0V!%N  
        ' Calculate new parameters with accommodation Z ,|1G6f@  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness PBxK>a  
    3PvZ_!G  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens H y.3ccZ0  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens jm#d7@~4  
    /XWPN(JC?  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ?l\gh1{C  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens a`EGx{q(  
    LH3N}J({  
        tlens = 3.767 + 0.04*A                  'Lens thickness ? RR Srr1  
    j,|1y5f  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Wvut)T  
    "W_jdE6v  
        'Adjust parameters to account for accommodation .WL\:{G8;  
    eB<V%,%N#  
        '************************************************************************* o-Q]Dk1W  
        'Aqueous thickness (Position of Lens)  \pewbu5^  
        '************************************************************************* rB.=f[aX[  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) !\&7oAs=I  
        GetCustomElement eID, entity h 0QYoDvbC  
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        parID = FindFullName( "Geometry.Arizona Eye" ) L5zG0mC8  
    DSDl[;3O{s  
        ' Delete any shift(s) in z UALg!M#  
        count = 0 c5B_WqjJ  
        While GetOperationCount(eID)>count T}w*K[z $  
            GetOperation eID, count, op CD8JYiJ  
            If op.Type="ShiftZ" Then JL.yd H79  
                DeleteOperation eID,count r'9=k x  
                count=count-1 @R'g@+{I  
            End If 9h3~;Q  
            count=count+1 VeN&rjc  
        Wend ."!8B9 s  
    ]df9'\  
        'Set new shift in {x&jh|f`g  
        op.Type = "ShiftZ" &-8-xw#.  
        op.val1 = taq os(Jr!p_=  
        op.parent = parID r.a9W? (E  
        AddOperation eID, op Cb@S </b  
        Print "Set aqueous humor thickness = " & taq-0.55 (}~eD  
    Z0F>"Z _qn  
        '************************************************************************* G3_mWppH  
        'Radius and conic constant of anterior lens ~G{$P'[  
        '************************************************************************* Hz3 S^o7  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) U&w 5&W{F}  
        GetConic eID, entity, curv, conic 6XOpB^@  
    -9H!j4]T?  
        SetConic eID, entity, 1/Rant, CCant 3'sWlhf;  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant QN}3S0  
    S\v&{  
        '************************************************************************* +4:+qGAJ{  
        'Radius and conic constant of posterior lens M[ ~2,M&H  
        '************************************************************************* 'a-5 U TT  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) t0asW5f  
        GetConic eID, entity, curv, conic <SC|A|  
    !aW*dD61  
        SetConic eID, entity, 1/Rpost, CCpost vY0V{u?J  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost o. V0iS]  
    ,I2re G  
        '************************************************************************* L>5!3b=b  
        'Lens thickness (Position of posterior lens surface) M;p q2$   
        '************************************************************************* :LIKp;  
    rt@-Pw!B  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) y`B!6p 5j  
    Z'EO   
        ' Delete any z-shift(s) )(ZPSg$/F  
        count = 0 >nIcF m  
        While GetOperationCount(eID)>count 8v)~J}[Bz  
            GetOperation eID, count, op @Pb 1QLiz  
            If op.Type="ShiftZ" Then mk`cyN>m  
                DeleteOperation eID,count P{i8  
                count=count-1 L$u&~"z-  
            End If 7]. IT(  
            count=count+1 y8~)/)l&  
        Wend zIYr0k*%  
    Acq>M^E3  
        'Set new z-shift WH*=81)zp  
        op.Type = "ShiftZ" S4:\`Lo-;  
        op.val1 = tlens 1M~:]}*<  
        op.parent = parID KEVy%AP=*h  
        AddOperation eID, op 0Li'a{n2  
        Print "Set lens thickness = " & tlens dpGQ0EzH^  
    5.K$ X$+7}  
        '************************************************************************* ux 79"5qb  
        'Lens index of refraction ,?~UpsUx  
        '************************************************************************* ! ^*;c#  
        eID = FindMaterial( "Lens" ) kJ<Xq   
        GetModelMaterial eID, mat %}]4Nsde  
    Mevyj;1t  
        mat.Nd = nlens ZhbY, wJ,  
        SetModelMaterial eID, mat agxSb^ 8tF  
        Print "Set lens index of refraction = " & nlens NK#"qK""k  
    @8M2'R\  
        '************************************************************************* .McoW7|Y  
        'Pupil diameter zc,9Qfn  
        '************************************************************************* xc]C#q  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) q(ET)xCeD  
    )|^<woli,  
        'Adjust pupil diameter (trimming volume inner hole) komxot[[  
    yE|} r  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" K^qUlyv  
    \,bFm,kC?  
        ' Adjust pupil location to just in front of the lens %:;[M|.  
        parID = FindFullName( "Geometry.Arizona Eye" ) Hv7D+ j8M  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) i!}nGJGg  
        count = 0 L z>{FOR  
        While GetOperationCount(eID)>count - 2na::<K  
            GetOperation eID, count, op [@)z$W  
            If op.Type="ShiftZ" Then /'=^^%&:B  
                DeleteOperation eID,count #z^1)7  
                count=count-1 JX@6Sg<  
            End If 'S D|ObBY  
            count=count+1 A&lgiR*ObT  
        Wend 09;'z  
        op.Type = "ShiftZ" F-7b`cF9[r  
        op.val1 = taq-0.01 8 8 =c3^  
        op.parent = parID H- qP>:  
        AddOperation eID, op HYYx*CJ)  
    @?cXa: tX  
        Print "Set pupil diameter = " & pupilDiam ~Ow23N  
    AFB 7s z  
        'Update AZ Eye subassembly Description *0@; kD=  
        eID = FindFullName( "Geometry.Arizona Eye" ) A8Z?[,Mq!  
        GetEntity eID, entity E?h2e~ ,]  
        entity.Description = "Accommodation = " & A & "D" ,, #rv-*  
        SetEntity eID, entity !2M[  
    GKx,6E#JM  
        Update y~ 4nF  
        Print "DONE!" d8 Nh0!  
         iXS-EB/  
    End Sub CU^3L|f2N  
    EC!Cv;'  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: T2_#[bk*d  
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    Accommodation = 4 Diopters yr 9)ga%  
    Pupil Diameter = 4 mm vyOC2c8  
    Set aqueous humor thickness = 2.81 ^8*SCM_A  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 _3G)S+ 7#  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 lLFBop  
    Set lens thickness = 3.927 Y+`-~ 88  
    Set lens index of refraction = 1.42672 0?;Hmq3  
    Set pupil diameter = 4 {s'_zS z  
    DONE! :w_1J'D}  
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    D!$ =oK  
    QQ:2987619807 {1U*: @j  
     
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