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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 Xy%||\P{)  
    PJ; WNo8  
    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。 HHZw-/ s,%  
    4b[bj").A  
    模型 kc0MQ TJU  
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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。 @I-,5F|r  
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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. #2s}s<Sc;  
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    光源 Zj!,3{jX^  
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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。 ;&n iZKoe  
    =y-yHRC7  
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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。 J/jkb3  
    qF4tjza;k  
    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。 (_|*&au J  
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    图2. 字母F光源的设定方法光 C{}PO u  
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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 [:.wCG5  
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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。 e2v`  
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    图4. 视网膜朗伯散射设定
    W]#w4Fp!  
    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。 u+Ix''Fn#%  
    2=- .@,6  
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    图5. 视网膜重点采样规格设定
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    脚本 h\UKm|BZ  
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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: 72d|Jbd  
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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。 !h4T3sO  
    余下的脚本计算与屈光度有关的所有参数。 o[cOL^Xd1  
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    分析 jcJ 4?  
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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。 $ uHQl#!;  
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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 6&os`!  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. p /-du^:2  
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    Dim entity As T_ENTITY n#g_)\  
    Dim op As T_OPERATION Q"dq_8\`U  
    Dim mat As T_MODELMATERIAL V?j,$LixY  
    Dim A As Double yuZLsH  
    Dim pupilDiam As Double UqI #F  
    Dim eID As Long (M$0'BV0  
    Dim parID As Long !CUl1L1DSi  
    Dim count As Integer L]H'$~xx*  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double [*^.$s(  
    Dim tlens As Double, nlens As Double &N^~=y^`C'  
    Dim curv As Double, conic As Double 2.aCo, Kb;  
    Dim ok As Long >`0U2K  
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    Sub Main %PYO9:n  
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        '用户输入对话框 KAClV%jP  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 4C=W~6~  
            TextBox 220,21,40,21,.TextBox1 'default: 0 Uw("+[5O0  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 LZn'+{\`  
            OKButton 40,91,90,21 LG&BWs!  
            CancelButton 190,91,90,21 TI DgIK  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 Ab ,^y  
            TextBox 220,49,40,21,.TextBox2 'default: 4 RqTO3Kf  
        End Dialog wnokP  
        Dim dlg As UserDialog 8X7??f1;Y  
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        ok = Dialog (dlg) |T6K?:U7  
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        If ok=0 Then    'cancel button was pressed A4tk</A  
            Print "Execution cancelled." wtek5C^  
            End !G3AD3  
        End If @q'kKVJs  
    ?$6H',u  
        'Assign accommodation and pupil diameter & use defaults if field left empty ;\*3A22 #  
        If dlg.TextBox1 = "" Then 9~Dg<wQ  
            A = 0           'Default accommodation tVRN3fJH  
        Else ,/w*sE  
            A = CDbl(dlg.TextBox1) .rtA sbp.!  
        End If 8z1z<\  
    7.h{"xOx{  
        If dlg.TextBox2 = "" Then G]=z ![$  
            pupilDiam = 4   'Default pupil diameter P$obID  
        Else C#U(POA  
            pupilDiam = CDbl(dlg.TextBox2) ",b:rgpRp  
        End If bgor W"'  
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        Print " " ln82pQD2Y~  
        Print "Accommodation = " & A & " Diopters" .gJ2P?  
        Print "Pupil Diameter = " & pupilDiam & " mm" 3s%?)z  
    ""-wM~^D  
        ' Calculate new parameters with accommodation 0VNLhM(LM  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness dTg`z,^F  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens TwkT|Piw S  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens DO: ,PZX  
    |R9Lben',  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 0#]fEi  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens n-ffX*zA(  
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        tlens = 3.767 + 0.04*A                  'Lens thickness +Y 7M7  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction 8S1@,O,  
    x4^nT=?6_  
        'Adjust parameters to account for accommodation 6|jZv~rS$  
    .#yg=t1C  
        '************************************************************************* {zb'Z Yz  
        'Aqueous thickness (Position of Lens) ]UvB+M]Lv)  
        '************************************************************************* XKjrS 9:  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) -8n1y[  
        GetCustomElement eID, entity  _<S!tW  
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        parID = FindFullName( "Geometry.Arizona Eye" ) rt+4-WuK>  
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        ' Delete any shift(s) in z OXQ*Xpc  
        count = 0 $wUYK%.  
        While GetOperationCount(eID)>count Jp=qPG|  
            GetOperation eID, count, op *I]]Ogpq=  
            If op.Type="ShiftZ" Then G)7U &B  
                DeleteOperation eID,count VExhN';  
                count=count-1 jSem/;  
            End If XJ<"S p  
            count=count+1 0/Q_% :  
        Wend dtR"5TL<~}  
    SxRJ{m~  
        'Set new shift in & BPYlfB1  
        op.Type = "ShiftZ" VIp|U{  
        op.val1 = taq g Q\.|'%  
        op.parent = parID A^OwT#  
        AddOperation eID, op |}G"^r  
        Print "Set aqueous humor thickness = " & taq-0.55 .RxTz9(  
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        '************************************************************************* %> XsKXj  
        'Radius and conic constant of anterior lens $nE{%?n-#  
        '************************************************************************* wsQnjT>  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 9+ 1{a.JO  
        GetConic eID, entity, curv, conic 8T3,56 >  
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        SetConic eID, entity, 1/Rant, CCant {"wF;*U.V  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 5eTA]  
    tyR?A>F4  
        '************************************************************************* AIHH@z   
        'Radius and conic constant of posterior lens -N' (2'  
        '************************************************************************* KTm^}')C8  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) M}|(:o3Yo  
        GetConic eID, entity, curv, conic #z(:n5$F  
    1TZ[i  
        SetConic eID, entity, 1/Rpost, CCpost m^ xTV-#l@  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost gNZwD6GMe?  
    nd' D0<%  
        '************************************************************************* M1Q&)am  
        'Lens thickness (Position of posterior lens surface) ]ae(t`\l^  
        '************************************************************************* fV"Y/9}(  
    Wg}KQ6 6  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) p cLKE ZK  
    f+:iz'b#U  
        ' Delete any z-shift(s) [E9iuym  
        count = 0 fJ Ll-H  
        While GetOperationCount(eID)>count #ZZe*B!s_  
            GetOperation eID, count, op `:C1Wo^<  
            If op.Type="ShiftZ" Then j3sz"(  
                DeleteOperation eID,count \m7\}Nbz0/  
                count=count-1 &;$uU  
            End If ;u2[Ww~k  
            count=count+1 k4s V6f  
        Wend ,l&?%H9q  
    !td!">r46e  
        'Set new z-shift 0ca0-vY  
        op.Type = "ShiftZ" I$"Z\c8;  
        op.val1 = tlens SWdmej[  
        op.parent = parID :%gc Sm  
        AddOperation eID, op ;2kQ)Bq"  
        Print "Set lens thickness = " & tlens ika*w  
    ,ojJ;w5D  
        '************************************************************************* oywPPVxj  
        'Lens index of refraction +`F(wk["m  
        '************************************************************************* "r6qFxY  
        eID = FindMaterial( "Lens" ) 1sXCu|\q  
        GetModelMaterial eID, mat U.TZd"  
    :cA P{rSe  
        mat.Nd = nlens !>Nlp,r&~  
        SetModelMaterial eID, mat .w4|$.H  
        Print "Set lens index of refraction = " & nlens @ 51!3jeu  
    CAc]SxLh  
        '************************************************************************* 9'( _*KSH  
        'Pupil diameter ho>@ $9  
        '************************************************************************* /o4_rzR?  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) n~0wq(8M  
    `*U@d%a  
        'Adjust pupil diameter (trimming volume inner hole) ]{tWfv|Xg8  
    bm;iX*~  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" O+-+=W  
    <);j5)/  
        ' Adjust pupil location to just in front of the lens 0@_8JB ?E  
        parID = FindFullName( "Geometry.Arizona Eye" ) N~|f^#L  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) *$7^.eHfdd  
        count = 0 :awa  
        While GetOperationCount(eID)>count TY]0aw2]|7  
            GetOperation eID, count, op \B')2phE  
            If op.Type="ShiftZ" Then g(P7CX+y  
                DeleteOperation eID,count }<G a e5  
                count=count-1 "pt[Nm76)8  
            End If |e8A)xM]wC  
            count=count+1 }'<Z&NW6  
        Wend $idToOkw  
        op.Type = "ShiftZ" -F`gRAr-  
        op.val1 = taq-0.01 E `N`  
        op.parent = parID Gh_5$@ hF  
        AddOperation eID, op Rs<S}oeLn  
    9@t&jznt<  
        Print "Set pupil diameter = " & pupilDiam oxFd@WV5  
    ]>)}xfL &,  
        'Update AZ Eye subassembly Description .NdsKhg b  
        eID = FindFullName( "Geometry.Arizona Eye" ) CMC p7- v  
        GetEntity eID, entity a3A-N] ;f  
        entity.Description = "Accommodation = " & A & "D" 8k{XUn  
        SetEntity eID, entity Q-, 4  
    '5$: #|-  
        Update 1mgw0QO  
        Print "DONE!" <> =(BAw  
         g?1bEOA!  
    End Sub :TrP3wV _  
    KXTk.\c  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: (QFZM"G  
    ^p4`o>  
    Accommodation = 4 Diopters >CCy2W^W  
    Pupil Diameter = 4 mm XPYf1H  
    Set aqueous humor thickness = 2.81 P Jb /tKC  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 |{M F o)  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 O0^Y1l  
    Set lens thickness = 3.927 H{P*d=9v  
    Set lens index of refraction = 1.42672 &}gH!5L m  
    Set pupil diameter = 4 [HXd|,~_j-  
    DONE! '( ETXQ@  
    Q-_;.xy#4  
    {w>ofyqfp&  
    QQ:2987619807 s/?(G L+Ae  
     
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