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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 FJvY`zqB  
    9=>q0D2  
    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。 &nEL}GM)E  
    "L3mW=!*  
    模型 wfo,r 7  
    $zP5Hzx  
    模型的定义如表1种所示,由半径、圆锥常数、折射率、阿贝数、到下一面的距离等一系列表面组成。一些参数由屈光度(A)来决定。 /A{ Zf'DI  
    #E]K*mE'  
    Table 1. AZ眼睛模型的定义
    &%OY"Y~bI!  
    在FRED中使用0屈光度来创建的,光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. &y!?R$?b  
    z0[@O)Sj  
    光源 &=lc]sk  
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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。 $tZ {>!N  
    ]dUG=dWO  
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    图1. 光源和提示信息使用
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    除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 @R&d<^I&M  
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    在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 ceUe*}\cr  
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    图2. 字母F光源的设定方法光 01r%K@ xX\  
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    图3. 字母F在视网膜上位置点列图
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    视网膜的散射 C]!2   
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    在散射文件中,有一个名为“Retina surface”的72%的反射型朗伯散射,它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射,改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 ^_]ZZin  
    b~aM=71  
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    图4. 视网膜朗伯散射设定
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    注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 <- \|>r Q  
    %7ngAIg  
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    图5. 视网膜重点采样规格设定
    sh :$J[  
    脚本 v~mVf.j1  
    h%/BZC^L]|  
    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: !1l~UB_  
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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。 D0Q9A]bD;  
    余下的脚本计算与屈光度有关的所有参数。 ^8 VW$}  
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    分析 ?~o`mg  
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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。 T]tP!a;K  
    Cx TAd[az  
    图7. 字母F在视网膜上颜色分析
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    脚本代码 t\,Y<9{w  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. JX&U?Z  
    9L>?N:%5  
    Dim entity As T_ENTITY WZ'Z"'  
    Dim op As T_OPERATION 7DAP_C  
    Dim mat As T_MODELMATERIAL ^`cv6;)  
    Dim A As Double ${T/b(NM  
    Dim pupilDiam As Double h4]^~stI  
    Dim eID As Long `\( ?^]WLa  
    Dim parID As Long 2F2Hl   
    Dim count As Integer 0=>$J WF  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Xl4}S"a  
    Dim tlens As Double, nlens As Double mG1~rI  
    Dim curv As Double, conic As Double j!4{+&Laq  
    Dim ok As Long :qE.(k1@5  
    KZ5%q.  
    Sub Main h7#\]2U$[5  
    ov+{<0Q  
        '用户输入对话框 4kL6aSqT  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ^("b~-cJ  
            TextBox 220,21,40,21,.TextBox1 'default: 0 AMyg>n!  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 *q6XK_  
            OKButton 40,91,90,21 -m^- p  
            CancelButton 190,91,90,21 <1*kXTN(  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 xUn"XkhP  
            TextBox 220,49,40,21,.TextBox2 'default: 4 boojq{cvYA  
        End Dialog 4v_Ac;2m&  
        Dim dlg As UserDialog lrE"phYk  
    vaeQ}F  
        ok = Dialog (dlg) OJm ]gb7  
    !Q>xVlPVu  
        If ok=0 Then    'cancel button was pressed t oA}0MI(:  
            Print "Execution cancelled." FxlH;'+Q  
            End 8c) eaDu  
        End If ]$g07 7o  
    t~L4wr{B  
        'Assign accommodation and pupil diameter & use defaults if field left empty Sqa9+' [  
        If dlg.TextBox1 = "" Then 3S3 a|_+%  
            A = 0           'Default accommodation @g#5d|U);  
        Else ! yJ0A m>  
            A = CDbl(dlg.TextBox1) 6_%Cd`4Z  
        End If Un]wP`  
    Ovx *  
        If dlg.TextBox2 = "" Then ykC3Z<pI.  
            pupilDiam = 4   'Default pupil diameter qU#A,%kcV  
        Else Q>$B.z  
            pupilDiam = CDbl(dlg.TextBox2) XHA|v^  
        End If qiet<F  
    $2W#'_K+  
        Print " " J!om"h  
        Print "Accommodation = " & A & " Diopters" L"jA#ULg  
        Print "Pupil Diameter = " & pupilDiam & " mm" -Mr_Ao`E  
    K^!#;,0  
        ' Calculate new parameters with accommodation WHx #;  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness &KMI C  
    N'y<<tTA  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens a &tWMxBr  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens -Y524   
    '=;e# C`<{  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ( K[e=0Rf  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens UnDCC_ud  
    pJFn 8&!J  
        tlens = 3.767 + 0.04*A                  'Lens thickness T8m]f<  
    = 9Yf o,F  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction }36AeJ7L  
    V<5. 4{[G  
        'Adjust parameters to account for accommodation *w;?&)8%  
    6-\Mf:%B  
        '************************************************************************* >\K=)/W2  
        'Aqueous thickness (Position of Lens) N&G'i.w/  
        '************************************************************************* v/ Ge+o0K  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ~0,v Q   
        GetCustomElement eID, entity 2:|vJ<Q  
    ,~cK]!:>s  
        parID = FindFullName( "Geometry.Arizona Eye" ) @{b5x>KX  
    A!GvfmzqIn  
        ' Delete any shift(s) in z 6{;6~?U  
        count = 0 O^\:J 2I(  
        While GetOperationCount(eID)>count 4Yvz-aSyO  
            GetOperation eID, count, op 9U;  
            If op.Type="ShiftZ" Then .=YV  
                DeleteOperation eID,count zx<t{e7  
                count=count-1 u)h {"pP  
            End If ^GV'Y  
            count=count+1 ,JI]Eij^  
        Wend \ C:Gx4K  
    5$+7Q$Gw  
        'Set new shift in {3KY:%6qj  
        op.Type = "ShiftZ" :g$"Xc8Zn  
        op.val1 = taq 0fstEExw  
        op.parent = parID =xkaF)AW&v  
        AddOperation eID, op o.r D  
        Print "Set aqueous humor thickness = " & taq-0.55 ue3 ].:  
    T x Mh_  
        '************************************************************************* r]LP=K1  
        'Radius and conic constant of anterior lens ;F1y!h67<  
        '************************************************************************* ^}2!fRKAmo  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) >A{e,&  
        GetConic eID, entity, curv, conic Btznms'  
    (@N ILK  
        SetConic eID, entity, 1/Rant, CCant waz5+l28  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Ag T)J  
    l'<&H#A;'  
        '************************************************************************* zATOFV  
        'Radius and conic constant of posterior lens |}^u<S8X  
        '************************************************************************* YCP D+  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) F ]X<q uuL  
        GetConic eID, entity, curv, conic [3=Y 9P:  
    Ma\%uEgTD  
        SetConic eID, entity, 1/Rpost, CCpost zdem}kBIe  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost d. d J^M  
    EyR/   
        '************************************************************************* >lmqPuf  
        'Lens thickness (Position of posterior lens surface) 'O 7:=l  
        '************************************************************************* 1d!s8um;  
    _ LgP  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) OE[7fDe'  
    w8 S pt  
        ' Delete any z-shift(s) V*JqC  
        count = 0 tMdSdJ8  
        While GetOperationCount(eID)>count R%LFFMVn  
            GetOperation eID, count, op IA}vN3  
            If op.Type="ShiftZ" Then 5fs,UH  
                DeleteOperation eID,count noaR3)  
                count=count-1 }x$@j  
            End If "< Di  
            count=count+1 C:&Sk\   
        Wend Ax|'uvVAPT  
    M'|[:I.V  
        'Set new z-shift mGg/F&G9  
        op.Type = "ShiftZ" !m=Js"  
        op.val1 = tlens BbFLT@W4  
        op.parent = parID q%bFR[p<*  
        AddOperation eID, op K_t >T)K  
        Print "Set lens thickness = " & tlens  [A,!3BN  
    sBWyUD  
        '************************************************************************* B.?F^m@zS  
        'Lens index of refraction Qu/f>tJN;  
        '************************************************************************* _)LXD,LA  
        eID = FindMaterial( "Lens" ) s hq +  
        GetModelMaterial eID, mat 3 P75:v  
    !iHC++D  
        mat.Nd = nlens kDJqT  
        SetModelMaterial eID, mat Mx0~^l  
        Print "Set lens index of refraction = " & nlens l`6.(6  
    ~f[;(?39xZ  
        '************************************************************************* 3J8>r|u;1'  
        'Pupil diameter IuFr:3(  
        '************************************************************************* RI<s mt.Ng  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) _8SB+s*  
    Qa2p34Z/  
        'Adjust pupil diameter (trimming volume inner hole) B(FM~TVZ  
    |gk4X%o6  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Y$, ++wx  
    d/+s-g p  
        ' Adjust pupil location to just in front of the lens `o9:6X?RA  
        parID = FindFullName( "Geometry.Arizona Eye" ) T6?03cSE  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) E>#@ H  
        count = 0 IEM{?  
        While GetOperationCount(eID)>count Bk~lM'  
            GetOperation eID, count, op kwww5p ["  
            If op.Type="ShiftZ" Then npytb*[|c  
                DeleteOperation eID,count fGH)Fgo`  
                count=count-1 <tO@dI$~>  
            End If 2ER_?y  
            count=count+1 "Ar|i8^G3  
        Wend "`S?q G  
        op.Type = "ShiftZ" s LDEa  
        op.val1 = taq-0.01 04-@c  
        op.parent = parID XdzC/ {G  
        AddOperation eID, op iBWEZw)  
    <AJRU l  
        Print "Set pupil diameter = " & pupilDiam iz[IK%K  
    SY.koW  
        'Update AZ Eye subassembly Description ^K8XY@{&  
        eID = FindFullName( "Geometry.Arizona Eye" ) xe.f]a  
        GetEntity eID, entity V2;Nv\J\  
        entity.Description = "Accommodation = " & A & "D" <%|u1cn~!v  
        SetEntity eID, entity @qWClr{`  
    FKe/xz  
        Update } nIYNeP?D  
        Print "DONE!" aWvC-vZk  
         @^# 9N!Fj]  
    End Sub Xmb##:  
    >pol'=  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: ?J+*i d  
    +?QHSIQo  
    Accommodation = 4 Diopters ~U]%>Zf  
    Pupil Diameter = 4 mm qauvwAMuX  
    Set aqueous humor thickness = 2.81 <Nloh+n=  
    Set anterior lens radius = 10.4 and conic constant = -2.375869  SN}3  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 1n*"C!q  
    Set lens thickness = 3.927 G7GKO  
    Set lens index of refraction = 1.42672 c8_,S[W  
    Set pupil diameter = 4 ,s}7KE  
    DONE! "WPWMQ+  
    P3a]*>.,  
    7bVKH[  
    QQ:2987619807 jCx*{TO  
     
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