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    [技术]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: 2021-10-22
    简介 gxmc|  
    GNU;jSh5  
    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。 /^2CGcT(  
    |>2: eH  
    模型 |<(t}}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。 A1-qtAO]  
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    Table 1. AZ眼睛模型的定义
    K-(;D4/sQE  
    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. cZi[(K  
    }OrYpZob  
    光源 N9]xJgTze  
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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。 M<(u A'  
    `?uPn~,e8  
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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。 FkB{ SC J  
    GwQn;gkF  
    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。 GMm'of#  
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    图2. 字母F光源的设定方法光 gs`> C(  
    ;|TT(P:d  
    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 f&yQhe6q  
    2-v\3voN  
    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。 ><Uk*mwL  
    C3S`}o.  
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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。 *48IF33&s  
    ` X}85  
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    图5. 视网膜重点采样规格设定
    El6bD% \G  
    脚本 @\}YAa>>"I  
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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: s'L?;:)dyB  
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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。 (1){A8=?o  
    余下的脚本计算与屈光度有关的所有参数。 J&6:d  
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    分析 Z;b+>2oL  
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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。 \+Y!ILOI  
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    图7. 字母F在视网膜上颜色分析
    l2&hBacT  
    脚本代码 \FifzKA  
    Jps .;yjk  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. }.{}A(^YR  
    :'*DMW~  
    Dim entity As T_ENTITY Np)aS[9W  
    Dim op As T_OPERATION 0H:dv:#WAI  
    Dim mat As T_MODELMATERIAL @2e2^8X7f  
    Dim A As Double DU{bonR`  
    Dim pupilDiam As Double ',mW`ZN  
    Dim eID As Long Fu)Th|5GZ  
    Dim parID As Long ax@H"d&  
    Dim count As Integer (ZPXdr  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double CV^c",b_  
    Dim tlens As Double, nlens As Double -x'e+zT  
    Dim curv As Double, conic As Double ^?"^Pmw  
    Dim ok As Long z{?4*Bq  
    6^YJ]w  
    Sub Main  @Fx@5e  
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        '用户输入对话框 nyhMnp#<  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 @]'S eiNp  
            TextBox 220,21,40,21,.TextBox1 'default: 0 m0( E kK  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 QzthTX<  
            OKButton 40,91,90,21 97!5Q~I  
            CancelButton 190,91,90,21 40K2uT{cq  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 8$}OS-  
            TextBox 220,49,40,21,.TextBox2 'default: 4 9L)L|4A.l  
        End Dialog @@} `hii  
        Dim dlg As UserDialog (5`T+pAsV  
    'sU)|W(3U  
        ok = Dialog (dlg) n33kb/q*  
    Alz~-hqQ  
        If ok=0 Then    'cancel button was pressed =! m JG  
            Print "Execution cancelled." S,vu]?-8  
            End 'G#SLqZy  
        End If Lk.h.ST  
    /iC_!nu  
        'Assign accommodation and pupil diameter & use defaults if field left empty ;^-:b(E  
        If dlg.TextBox1 = "" Then J22r v(  
            A = 0           'Default accommodation c8ZCs?   
        Else ,w`~K:b.  
            A = CDbl(dlg.TextBox1) G5c7:iGm/c  
        End If NWKi ()nA%  
    (9GbG"   
        If dlg.TextBox2 = "" Then ULl_\5s2  
            pupilDiam = 4   'Default pupil diameter iBvOJs  
        Else I; j3*lV_  
            pupilDiam = CDbl(dlg.TextBox2) Z?1OdoT-  
        End If ?q Xs-  
    ;~/4d-  
        Print " " 4lz{G*u  
        Print "Accommodation = " & A & " Diopters" -JTG?JOd]  
        Print "Pupil Diameter = " & pupilDiam & " mm" dlD}Ub  
    XxOn3i  
        ' Calculate new parameters with accommodation r95zP]T  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness K`4GU[ul  
    GqUSVQ  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens POGw`:)A  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 8:{ q8xZ=k  
    .~`Y)PON  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens d=F-L  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens yGEb7I$h  
    }O*WV1  
        tlens = 3.767 + 0.04*A                  'Lens thickness MY F#A  
    \ X$)vK  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 0Q1/n2V  
    ~3=2=Uf  
        'Adjust parameters to account for accommodation v~5<:0dL  
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        '************************************************************************* p\S8oHWe  
        'Aqueous thickness (Position of Lens) 0Hcbkep9D  
        '************************************************************************* <]Y[XI(kr  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) "{( [!  
        GetCustomElement eID, entity Gah lS*W  
    k18$JyaG  
        parID = FindFullName( "Geometry.Arizona Eye" ) Y:pRcO.4g  
    hTw}X.<4  
        ' Delete any shift(s) in z Jz$ >k$!UD  
        count = 0 RWikJ   
        While GetOperationCount(eID)>count |s|/]aD}o  
            GetOperation eID, count, op K-4tdC3  
            If op.Type="ShiftZ" Then v@_in(dk  
                DeleteOperation eID,count Mi74Xl i  
                count=count-1 ,qy&|4Jz  
            End If uaxB -PZ  
            count=count+1 ^saM$e^c:  
        Wend 'v`_Ii|-  
    D5` (}  
        'Set new shift in BKA]G)G7u!  
        op.Type = "ShiftZ" q\H7& w  
        op.val1 = taq k7Oy5$##  
        op.parent = parID 3bts7<K=  
        AddOperation eID, op k4R4YI"jV  
        Print "Set aqueous humor thickness = " & taq-0.55 }17bV, t  
    fuyl/bx}  
        '************************************************************************* -eL'KO5'  
        'Radius and conic constant of anterior lens QUp?i  
        '************************************************************************* GP]TnQ<*;  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) }ecs Gw  
        GetConic eID, entity, curv, conic )ddsyFGW  
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        SetConic eID, entity, 1/Rant, CCant xjrlc9  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant <gcmsiB|  
    la702)N{  
        '************************************************************************* b~as64  
        'Radius and conic constant of posterior lens \`gEu{  
        '************************************************************************* +H}e)1^ I  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) u]*5Ex(?  
        GetConic eID, entity, curv, conic :#SNpn=@  
    ]xrD<  
        SetConic eID, entity, 1/Rpost, CCpost f0FP9t3k  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost .K7C-Xn=  
    )* 3bkKVB  
        '************************************************************************* yFO)<GLk  
        'Lens thickness (Position of posterior lens surface) 4:3_ER]J  
        '************************************************************************* 6n-r  
    z1Q2*:)c  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) J)huy\>,  
    jGiw96,Y  
        ' Delete any z-shift(s) raHVkE{<  
        count = 0 B^m!t7/,  
        While GetOperationCount(eID)>count r=0j7^B#  
            GetOperation eID, count, op $rTu6(i1  
            If op.Type="ShiftZ" Then 4k$0CbHx0  
                DeleteOperation eID,count 0etwz3NuW  
                count=count-1 >{F!ntEj  
            End If l $w/Fz  
            count=count+1 kp; &cQu!  
        Wend cz>mhD  
    InN{^uN  
        'Set new z-shift X~zRZ0  
        op.Type = "ShiftZ" w&C1=v -h  
        op.val1 = tlens EW9b*r7./  
        op.parent = parID ,`"K  
        AddOperation eID, op SS0_P jKz  
        Print "Set lens thickness = " & tlens !l"tI#?6W%  
    @it/$>R^)  
        '************************************************************************* E [*0Bo]  
        'Lens index of refraction U1kh-8  :  
        '************************************************************************* lG 8dI\`  
        eID = FindMaterial( "Lens" ) 1b+h>.gWar  
        GetModelMaterial eID, mat b-4dsz 'ai  
    dm  2EH  
        mat.Nd = nlens `x*/UCy\  
        SetModelMaterial eID, mat OF-WUa4t  
        Print "Set lens index of refraction = " & nlens ) H+d.Y  
    GVZTDrC  
        '************************************************************************* L?Tu)<Mn  
        'Pupil diameter Oc~VHT  
        '************************************************************************* \H[Yyp4  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) :ovt?q8">  
    a_AJ)4  
        'Adjust pupil diameter (trimming volume inner hole) L,W:,i/C  
    `OBl:e  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" V:8@)Hc=  
    J7Sx!PQ  
        ' Adjust pupil location to just in front of the lens _1\poAy  
        parID = FindFullName( "Geometry.Arizona Eye" ) k|5k8CRX  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) @Rf^P(  
        count = 0 SlT7L||Ww  
        While GetOperationCount(eID)>count ovSH}h!  
            GetOperation eID, count, op @x*.5:[  
            If op.Type="ShiftZ" Then p$XnOh  
                DeleteOperation eID,count DEcGFRgN~  
                count=count-1 S,VyUe4P4  
            End If <irpmRQr  
            count=count+1 '?b\F~$8  
        Wend N-xnenci  
        op.Type = "ShiftZ" -FaaFw:Z;A  
        op.val1 = taq-0.01 *cPN\Iu.W  
        op.parent = parID .}`V I`z*  
        AddOperation eID, op }\ EL;sT  
    lj Y  
        Print "Set pupil diameter = " & pupilDiam !9PX\Xbn  
    JC/d:.  
        'Update AZ Eye subassembly Description 5Vm Eyb  
        eID = FindFullName( "Geometry.Arizona Eye" ) T"IW Jpc  
        GetEntity eID, entity sc9]sIb  
        entity.Description = "Accommodation = " & A & "D" dt0T t  
        SetEntity eID, entity PQi }Evxa  
    eA1'qww"'  
        Update =^#0.  
        Print "DONE!" E~}[+X@  
         y1nP F&_  
    End Sub |MVV +.X  
    'Z y{mq\  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: u!M& ;QL  
    8z?$t-DO  
    Accommodation = 4 Diopters ^^7gDgT  
    Pupil Diameter = 4 mm A_aO }oBX  
    Set aqueous humor thickness = 2.81 \6Xn]S  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 f^~2^p 1te  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 7WXiG0  
    Set lens thickness = 3.927 K[n<+e;G  
    Set lens index of refraction = 1.42672 [+_\z',u  
    Set pupil diameter = 4 5%'o%`?i  
    DONE! vu44!c@  
     
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