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    [分享]Arizona眼睛模型 [复制链接]

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    离线infotek
     
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    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 A]j}'  
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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。 n? ]f@OR  
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    模型 u^l*5F%DK  
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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。 dN<5JQql  
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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. $~=2{  
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    光源 v`SY6;<2  
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    多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 V/+Jc( N  
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    图1. 光源和提示信息使用
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    除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 WO@H*  
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    在往下看是内置的脚本用来修改屈光度,使其为4(250mm),光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 jXWNHIl)@  
    D M}s0O$ 0  
    图2. 字母F光源的设定方法光 3%2jwR  
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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 |Ytg  
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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。 V!xwb:J  
    *> KHRR<N  
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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。 (f~gEKcB2u  
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    图5. 视网膜重点采样规格设定
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    脚本 (Xo SG  
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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: sPy2/7Wqd  
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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。 YjLe(+ WQ  
    余下的脚本计算与屈光度有关的所有参数。 U CRAw3=  
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    分析 4\6: \  
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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。 ~{M@?8wi  
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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 *,lh:  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. ~@Kf2dHes  
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    Dim entity As T_ENTITY  rN"Xz  
    Dim op As T_OPERATION 2xn<E>]  
    Dim mat As T_MODELMATERIAL ^i'y6J  
    Dim A As Double ZPyM>XK$4  
    Dim pupilDiam As Double  s4$X  
    Dim eID As Long etyCrQ ?U  
    Dim parID As Long NR4Jn?l{  
    Dim count As Integer #6W,6(#^#  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double nm@']  
    Dim tlens As Double, nlens As Double qVBL>9O*.  
    Dim curv As Double, conic As Double p7C!G1+z  
    Dim ok As Long AIh*1>2Xn  
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    Sub Main *vnXlV4L  
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        '用户输入对话框 }1U*A#aN7K  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 #3 bv3m  
            TextBox 220,21,40,21,.TextBox1 'default: 0 9&K/GaG  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 2\0Oji\6  
            OKButton 40,91,90,21  AmcC:5  
            CancelButton 190,91,90,21 .X `C^z]+  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 OOB^gf}$'  
            TextBox 220,49,40,21,.TextBox2 'default: 4 >SDp uG&>  
        End Dialog [U.v:tR   
        Dim dlg As UserDialog {Q~7M$  
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        ok = Dialog (dlg) <9ifPSvJ  
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        If ok=0 Then    'cancel button was pressed T2weAk#J  
            Print "Execution cancelled." = .`jjDJ  
            End A#DR9Eq  
        End If |RhM| i  
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        'Assign accommodation and pupil diameter & use defaults if field left empty eH <Jng  
        If dlg.TextBox1 = "" Then kus}W  J  
            A = 0           'Default accommodation |!LnAh  
        Else 2 9#]Vr  
            A = CDbl(dlg.TextBox1) ?QpNjsF  
        End If 3KcaT5(&  
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        If dlg.TextBox2 = "" Then ^o d<JD4  
            pupilDiam = 4   'Default pupil diameter 'jvpNn  
        Else 2o5;Uz1{  
            pupilDiam = CDbl(dlg.TextBox2) `;F2n2@  
        End If 6RK\}@^=K  
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        Print " " &5Y_>{,  
        Print "Accommodation = " & A & " Diopters" - k`.j  
        Print "Pupil Diameter = " & pupilDiam & " mm" it1/3y =]  
    `.^ |]|u  
        ' Calculate new parameters with accommodation YG[w@u  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness &[j]Bp?  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens 8eyl,W=dn  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens [e e30ELn  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens T PYDs+U  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens N:W9},  
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        tlens = 3.767 + 0.04*A                  'Lens thickness ^M[P-#X_  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction '*!L!VJ  
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        'Adjust parameters to account for accommodation ~V+l_ :  
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        '************************************************************************* 8MZ$T3IM  
        'Aqueous thickness (Position of Lens) C2/}d? bki  
        '************************************************************************* A3+6 #?:;  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ycX{NDGs  
        GetCustomElement eID, entity o""~jc~  
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        parID = FindFullName( "Geometry.Arizona Eye" ) p;%<mUI  
    6 hiC?2b{x  
        ' Delete any shift(s) in z 4JO@BV>t  
        count = 0 |_zO_Frtp  
        While GetOperationCount(eID)>count ;BBpN`T  
            GetOperation eID, count, op @8gEH+r  
            If op.Type="ShiftZ" Then b{&FuvQg2  
                DeleteOperation eID,count =r6qX  
                count=count-1 n?QZFeI`  
            End If (vyz;Ob  
            count=count+1 OJ,m1{9$}  
        Wend t9u|iTY f!  
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        'Set new shift in 5w<A;f  
        op.Type = "ShiftZ" .j?kEN?w  
        op.val1 = taq m#H_*L0  
        op.parent = parID x$B&L`QV  
        AddOperation eID, op Pil;/t)"  
        Print "Set aqueous humor thickness = " & taq-0.55 lLiQ;@  
    '%7 Bxof  
        '************************************************************************* fx?$9(r,  
        'Radius and conic constant of anterior lens =`t^~.5  
        '************************************************************************* N|dD!  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) A3R#z]Ub  
        GetConic eID, entity, curv, conic M_1;$fWq  
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        SetConic eID, entity, 1/Rant, CCant PK:2xN:=  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant <P4 FzK  
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        '************************************************************************* eegx'VSX4  
        'Radius and conic constant of posterior lens E1*QdCV2  
        '************************************************************************* qd6fU^)i  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) =m tY  
        GetConic eID, entity, curv, conic n-afDV  
    + ^ yq;z  
        SetConic eID, entity, 1/Rpost, CCpost s3 B'>RG}  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost v1+U;Th>g  
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        '************************************************************************* .-]R9KjR1J  
        'Lens thickness (Position of posterior lens surface) >l5u54^3K  
        '************************************************************************* |>1hu1  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) S!Jh2tsg`-  
    ' Q7Y-V  
        ' Delete any z-shift(s) jRQ+2@n{E  
        count = 0 1oY^]OD]W  
        While GetOperationCount(eID)>count T>d.#  
            GetOperation eID, count, op \N6\v5vh  
            If op.Type="ShiftZ" Then p3]Q^KFS  
                DeleteOperation eID,count ]<trA$ 0  
                count=count-1 pJ^NA2  
            End If xeA#u J  
            count=count+1 "/+zMLY  
        Wend ZFxLBb:  
    ,sQ93(Vo  
        'Set new z-shift <$i4?)f(  
        op.Type = "ShiftZ" ^[q /Mw  
        op.val1 = tlens RFfIF]~3  
        op.parent = parID sC7/9</  
        AddOperation eID, op Zi ESlf$  
        Print "Set lens thickness = " & tlens ?Rr2/W#F  
    X?Pl<l&  
        '************************************************************************* " ;NRzY  
        'Lens index of refraction \8v91g91f  
        '************************************************************************* E^V |  
        eID = FindMaterial( "Lens" ) -Zc![cAlO  
        GetModelMaterial eID, mat Op}ZB:  
    =1hr2R(V  
        mat.Nd = nlens `8g7q 5  
        SetModelMaterial eID, mat Ciihsm  
        Print "Set lens index of refraction = " & nlens "@ E3MTW  
    u$*>`Xe6  
        '************************************************************************* #@f[bP}a  
        'Pupil diameter v#oi0-9o[  
        '************************************************************************* #1/}3+=5B  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) SoQR#(73HK  
    i*[n{=*l@  
        'Adjust pupil diameter (trimming volume inner hole) D$r Uid  
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        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" &t}?2>:  
    M {a #  
        ' Adjust pupil location to just in front of the lens _GA$6#]  
        parID = FindFullName( "Geometry.Arizona Eye" ) j,-C{ K  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) m5c&&v6%"b  
        count = 0 e x?v `9  
        While GetOperationCount(eID)>count k$7Z^~?Fz  
            GetOperation eID, count, op !{UTD+|=N  
            If op.Type="ShiftZ" Then e@]-D FG  
                DeleteOperation eID,count Af-UScD%G  
                count=count-1 TwahR:T   
            End If dQ:cYNm  
            count=count+1 `'4)q}bB  
        Wend N|Cs=-+  
        op.Type = "ShiftZ" `: |@Zln  
        op.val1 = taq-0.01 jgu*Y{ocm  
        op.parent = parID i!H!;z#  
        AddOperation eID, op OSDy'@   
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        Print "Set pupil diameter = " & pupilDiam +}kgQ^  
    x4kWLy7Sz  
        'Update AZ Eye subassembly Description X9=N%GY[  
        eID = FindFullName( "Geometry.Arizona Eye" ) [xlIG}e9  
        GetEntity eID, entity b{Zpux+  
        entity.Description = "Accommodation = " & A & "D" 2& LQg=O  
        SetEntity eID, entity vZAv_8S)  
    B(5c9DI`  
        Update 8*a), 3aK  
        Print "DONE!" @w9{5D4  
         1 Y/$,Oa5  
    End Sub ]7YNIS  
    -*ELLY[  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: ^))RM_ic  
    eVz#7vqv   
    Accommodation = 4 Diopters msx-O=4g  
    Pupil Diameter = 4 mm F2I 5q C/  
    Set aqueous humor thickness = 2.81 gX @`X  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 PGn);Baq  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 nHOr AD|&  
    Set lens thickness = 3.927 6z,Dyy]tl  
    Set lens index of refraction = 1.42672 y-aRXF=W  
    Set pupil diameter = 4 ?A*Kg;IU  
    DONE! oOU1{[  
    J ++v@4Z  
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    QQ:2987619807 gBw^,)Q{0Y  
     
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