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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 8?t"C_>*e  
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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。 =! Vf  
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    模型 %,@vWmn  
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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。 /5AW?2)  
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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. +,+vkpL-%  
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    光源 %ugHhS!  
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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。 )o1eWL}  
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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。 B(k=oXDF  
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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。 wCMQPt)VS  
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    图2. 字母F光源的设定方法光 Hi! Jj  
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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 S&O3HC  
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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。 DVZdClAL  
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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。 K`}{0@ilCw  
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    图5. 视网膜重点采样规格设定
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    脚本 5cr(S~Q;  
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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: !9*c8bL D  
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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。 sRVIH A ,  
    余下的脚本计算与屈光度有关的所有参数。 gieN9S  
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    分析 N(6|yZ<J3M  
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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。 s>_V   
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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 &K_)#v`|  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. #v#<itfFH  
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    Dim entity As T_ENTITY ;rI@ *An  
    Dim op As T_OPERATION p?[Tm*r  
    Dim mat As T_MODELMATERIAL k- V,~c  
    Dim A As Double +=Jir1SLV  
    Dim pupilDiam As Double ;a=w5,h:  
    Dim eID As Long m^'uipa\  
    Dim parID As Long ?7:KphFX)  
    Dim count As Integer rrg96WD  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double waX>0e  
    Dim tlens As Double, nlens As Double v}@xlB=  
    Dim curv As Double, conic As Double ~vLW.:  
    Dim ok As Long rn DCqv!'P  
    ?oZR.D|SZ  
    Sub Main V^y^ ;0I}[  
    Z UKf`m[  
        '用户输入对话框 U<XSj#&8|  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 _(J&aY\  
            TextBox 220,21,40,21,.TextBox1 'default: 0 @3fn)YQ'  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 9[!,c`pw  
            OKButton 40,91,90,21 _AV1WS;^^8  
            CancelButton 190,91,90,21 O/:UJ( e{  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 tH=P6vY  
            TextBox 220,49,40,21,.TextBox2 'default: 4 j Ja$a [  
        End Dialog XxHx:mi  
        Dim dlg As UserDialog 2._X|~0a  
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        ok = Dialog (dlg) %0#1t 5g  
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        If ok=0 Then    'cancel button was pressed d]9U^iy  
            Print "Execution cancelled." jq'!UN{  
            End l4T7'U>`  
        End If Li*eGlId  
    ld$i+6|   
        'Assign accommodation and pupil diameter & use defaults if field left empty r&-m=Kk$  
        If dlg.TextBox1 = "" Then '|;X0fD  
            A = 0           'Default accommodation .xf<=ep  
        Else b~dIk5>O  
            A = CDbl(dlg.TextBox1) 1[_mEtM:]B  
        End If <2C7<7{7  
    +C7 ~b~ %  
        If dlg.TextBox2 = "" Then Zmbfq8K  
            pupilDiam = 4   'Default pupil diameter 4|A>b})H  
        Else </uO e.l>Q  
            pupilDiam = CDbl(dlg.TextBox2) t|t#vcB  
        End If aq7~QX_0G  
    !w BJ,&E  
        Print " " #plY\0E@  
        Print "Accommodation = " & A & " Diopters" $mF_,|  
        Print "Pupil Diameter = " & pupilDiam & " mm" j }b\Z9)!  
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        ' Calculate new parameters with accommodation 8* Jw0mSw  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness %s19KGpA  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens @p\}pY$T  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens Dk48@`l2  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Vh>Z,()>>@  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens @cU&n6C@  
    % `Z! 4L  
        tlens = 3.767 + 0.04*A                  'Lens thickness P2 Vg4   
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction `y+tf?QN  
    Ov<NsNX]  
        'Adjust parameters to account for accommodation 9@+5LZR  
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        '************************************************************************* @k&qb!Qah  
        'Aqueous thickness (Position of Lens) |Ph3#^rM?  
        '************************************************************************* YKQr, Now  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Q_l'o3  
        GetCustomElement eID, entity /dnCwFXf  
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        parID = FindFullName( "Geometry.Arizona Eye" ) m,fAeln  
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        ' Delete any shift(s) in z },|M9 I0  
        count = 0 V59(Z  
        While GetOperationCount(eID)>count hlt[\LP=$  
            GetOperation eID, count, op s(W|f|R  
            If op.Type="ShiftZ" Then =-p$jXVW%  
                DeleteOperation eID,count m.,U:>  
                count=count-1 ID/ F  
            End If O*#*%RL|  
            count=count+1 6Aocm R0D'  
        Wend aMTu-hA  
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        'Set new shift in )=Jk@yj8x  
        op.Type = "ShiftZ" B7imV@<  
        op.val1 = taq bJs9X/E  
        op.parent = parID &r:7g%{n  
        AddOperation eID, op gCyW Vp  
        Print "Set aqueous humor thickness = " & taq-0.55 ,a#EW+" Z  
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        '************************************************************************* G8Du~h!!U  
        'Radius and conic constant of anterior lens $8BPlqBIZ  
        '************************************************************************* *?MGMhE  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) NIw\}[-Z0E  
        GetConic eID, entity, curv, conic 6uR^%W8]  
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        SetConic eID, entity, 1/Rant, CCant -lv)tHs<  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant p) +k=b  
    /&4U6a  
        '************************************************************************* c*~]zR>s!  
        'Radius and conic constant of posterior lens 8g7<KKw  
        '************************************************************************* }u1O#L}F5  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) )vxUT{;sH  
        GetConic eID, entity, curv, conic 3 h<,  
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        SetConic eID, entity, 1/Rpost, CCpost vhhC> 7  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost o6p98Dpg   
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        '************************************************************************* jRatm.N  
        'Lens thickness (Position of posterior lens surface) TiH) 5  
        '************************************************************************* B/n[m@O  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) "!EcbR  
    x,'!eCKN  
        ' Delete any z-shift(s) :<|<|qJWo  
        count = 0 ]~Z6;  
        While GetOperationCount(eID)>count Qa.u Mq  
            GetOperation eID, count, op zen*PeIrA^  
            If op.Type="ShiftZ" Then =)7s$ p  
                DeleteOperation eID,count @$z<i `4  
                count=count-1 &zo|Lfe  
            End If \Acqr@D  
            count=count+1 vI@%Fg+D  
        Wend D:K4H+ch  
    L{c q, jk  
        'Set new z-shift y\x+  
        op.Type = "ShiftZ" J4\qEO  
        op.val1 = tlens ? C/Te)  
        op.parent = parID }-@`9(o`)  
        AddOperation eID, op x+]\1p  
        Print "Set lens thickness = " & tlens m1*O0Tg]"  
    dc rSz4E|>  
        '************************************************************************* KSrx[q  
        'Lens index of refraction x]33LQ1]  
        '************************************************************************* uDZT_c'Y  
        eID = FindMaterial( "Lens" ) nakYn  
        GetModelMaterial eID, mat )[Yv?>ib  
    /g4f`$a  
        mat.Nd = nlens c?@T1h4  
        SetModelMaterial eID, mat ~ _!F01s  
        Print "Set lens index of refraction = " & nlens 42qYg(tZ  
    q?ix$nKOv  
        '************************************************************************* vz!s~cAt  
        'Pupil diameter Kx%Sku<F'  
        '************************************************************************* Z@$8I{}G  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) R`~z0 d.  
    (V HL{rj  
        'Adjust pupil diameter (trimming volume inner hole) >_LDMs[-p  
    qQH]`#P  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 5;{H&O9Q  
    $ O5UyKI  
        ' Adjust pupil location to just in front of the lens wLH] <k  
        parID = FindFullName( "Geometry.Arizona Eye" ) D~\$~&_]=  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) [r[ =W!  
        count = 0 .?hP7;hhI  
        While GetOperationCount(eID)>count )[|3ZP`  
            GetOperation eID, count, op >MvDVPi~+  
            If op.Type="ShiftZ" Then Y"wUt &  
                DeleteOperation eID,count <(-hx+^  
                count=count-1 pLzk   
            End If Kc^;vT>3  
            count=count+1 *VZ5B<Ic  
        Wend oo.2Dn6z  
        op.Type = "ShiftZ" 0a"c2J  
        op.val1 = taq-0.01 Xqm::1(-(  
        op.parent = parID I2nhqJy^  
        AddOperation eID, op uF3qD|I\  
    J>bJ 449B  
        Print "Set pupil diameter = " & pupilDiam X7g1:L1Ys  
    E2{FK)qT  
        'Update AZ Eye subassembly Description >#y^;/bb  
        eID = FindFullName( "Geometry.Arizona Eye" ) 5EfS^MRf\n  
        GetEntity eID, entity KFwzy U"  
        entity.Description = "Accommodation = " & A & "D" d:U9pC$  
        SetEntity eID, entity oGRhnP'PF+  
    g'm+/pU)w)  
        Update ]V#M%0:Q82  
        Print "DONE!" [n$BRk|  
         ^~A>8CQOU  
    End Sub i|m3mcI%2  
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    如果屈光度是4,光瞳直径是4,则会输出如下数据: 5x>}O3Q_  
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    Accommodation = 4 Diopters \9g+^vQg  
    Pupil Diameter = 4 mm jE/AA!DC#  
    Set aqueous humor thickness = 2.81  pn5Q5xc  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 wD]/{ jw  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 "UJ S5[7$  
    Set lens thickness = 3.927 dp*u9z~NA  
    Set lens index of refraction = 1.42672 ~'CE[G5  
    Set pupil diameter = 4 /Dj=iBO  
    DONE! Q{lpKe0  
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    QQ:2987619807 >b{q.  
     
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