切换到宽版
  • 广告投放
  • 稿件投递
  • 繁體中文
    • 1768阅读
    • 0回复

    [分享]Arizona眼睛模型 [复制链接]

    上一主题 下一主题
    离线infotek
     
    发帖
    6634
    光币
    27319
    光券
    0
    只看楼主 倒序阅读 楼主  发表于: 2020-12-09
    简介 G^ZkY  
    un^IQMIh  
    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。 1ysLZ;K  
    ,*Z[P%<9  
    模型 aaug u.9  
    (I[h.\%  
    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。 /N]Ow  
    Mr NOcx&  
    Table 1. AZ眼睛模型的定义
    q AVfbcb  
    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. xFm{oJ!]&  
    ar qLp|  
    光源 lZA>L, \d  
    ]t*P5  
    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。 .-u k   
    _{`'{u  
    YeExjC  
    图1. 光源和提示信息使用
    DET!br'z5  
    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。 h NOYFH  
    R`C_CsXir  
    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。 )|h;J4V  
    v8vh~^X%P  
    图2. 字母F光源的设定方法光 k *;{n8o?)  
    B mBzOk^  
    图3. 字母F在视网膜上位置点列图
    mf;^b.mKh  
    视网膜的散射 FSwgPIO>  
    [OoH5dD  
    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。 G E~(N N  
    So\|Ye  
    aC8,Y$>?E`  
    图4. 视网膜朗伯散射设定
    }M9DqZ;I  
    注意在视网膜的表面有散射重点采样规格定义,在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳,半角度10度。 p]V-<  
    enbN0  
    KB,~u*~!  
    图5. 视网膜重点采样规格设定
    /Xu;/MMpd3  
    脚本 QVG0>,+}$  
    3^A/`8R7K  
    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: >.O*gv/ _  
    %I|+_ z&x  
    图6. 用户对话框的创建与编辑
    J<($L}T*$  
    图7. 用户对话框编辑器
    Zn<(,e  
    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。 l q\'  
    余下的脚本计算与屈光度有关的所有参数。  ny  
    V:F+HMBk  
    分析 CVGOX z  
    (@WDvgi(  
    屈光度为4,光瞳直径为4mm,字母F点在视网膜上所成的像。 Hc&uE3=%sL  
    =8$0$d  
    图7. 字母F在视网膜上颜色分析
    Ql: b1C,  
    脚本代码 \o62OfF!  
    }KD7 Y  
    Option Explicit     'Remove this to enable non-dimensioned variables to be used. v`_i1h9p{  
    wHt#'`5  
    Dim entity As T_ENTITY 0x]OF8=J  
    Dim op As T_OPERATION ){Ciu[h  
    Dim mat As T_MODELMATERIAL g]==!!^<D  
    Dim A As Double w$b+R8.n)  
    Dim pupilDiam As Double N[a ljC-R  
    Dim eID As Long 47C(\\  
    Dim parID As Long *< $c =  
    Dim count As Integer s}[A4`EWH  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double .o\;,l2  
    Dim tlens As Double, nlens As Double ;* wT,2;  
    Dim curv As Double, conic As Double n{.*El>{  
    Dim ok As Long M|[@znzR<  
    jHu,u|e0>S  
    Sub Main yUD_ w  
    _>gXNS r4u  
        '用户输入对话框 +(=0CA0GE  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Mz/]DJ8  
            TextBox 220,21,40,21,.TextBox1 'default: 0 9zoT6QP4  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 wr3_Bf3]  
            OKButton 40,91,90,21 t?]\M&i&  
            CancelButton 190,91,90,21 F=-uDtQ <N  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 Z^'?|qFj!  
            TextBox 220,49,40,21,.TextBox2 'default: 4 5#TrCPi6A  
        End Dialog P0'e"\$  
        Dim dlg As UserDialog KrdZEi vb  
    ,Lt~u_lve  
        ok = Dialog (dlg) IFd )OZ5  
    inr%XS/m  
        If ok=0 Then    'cancel button was pressed o~OwE7H)A  
            Print "Execution cancelled." [):{5hMA  
            End 6?3/Ul }  
        End If i\kTm?BQZ  
    &\J?[>EJ.  
        'Assign accommodation and pupil diameter & use defaults if field left empty T:K"  
        If dlg.TextBox1 = "" Then Ss@u,`pr  
            A = 0           'Default accommodation %XEKhy  
        Else @9}),hl`  
            A = CDbl(dlg.TextBox1) "*Lj8C3|n  
        End If *3A3>Rwu  
    bx hPjAL  
        If dlg.TextBox2 = "" Then )z2|"Lp  
            pupilDiam = 4   'Default pupil diameter G$?|S@I,  
        Else 0[n c7)sW  
            pupilDiam = CDbl(dlg.TextBox2) D~G5]M,}$  
        End If Xt</ -`  
    $$haVY&  
        Print " " u-AWJc+F.  
        Print "Accommodation = " & A & " Diopters" `3 f_d}b  
        Print "Pupil Diameter = " & pupilDiam & " mm" ,N;))3  
    5kGxhD  
        ' Calculate new parameters with accommodation [D*J[?yt  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Vk MinE  
    ^=eq .(>  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens Wmzq  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens q+YuVQ-fx  
    E S#rs="  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ZWf-X  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens [<]Y+33  
    1 L+=|*:  
        tlens = 3.767 + 0.04*A                  'Lens thickness !UBy%DN~k  
    V~/.Y&WN  
        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction YniZ( ~^K  
    Ze-MAt  
        'Adjust parameters to account for accommodation 8|1`Tn}o  
    T?W[Z_D  
        '************************************************************************* i LF^%!:X%  
        'Aqueous thickness (Position of Lens) UH5w7M  
        '************************************************************************* ,/i_QgP  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ANckv|&'v  
        GetCustomElement eID, entity . _1jk  
    J&A;#<qY  
        parID = FindFullName( "Geometry.Arizona Eye" ) U{73Xax  
    "e~k-\^Y  
        ' Delete any shift(s) in z jr9&.8%W:v  
        count = 0 /nc~T3j  
        While GetOperationCount(eID)>count RS'} nY}  
            GetOperation eID, count, op |r5e{  
            If op.Type="ShiftZ" Then q\a[S*  
                DeleteOperation eID,count o:_^gJ+|  
                count=count-1 HV ;;  
            End If 92!JKZe  
            count=count+1 Q(lku"U'  
        Wend Ee&hG[sx  
     OQ6sv/  
        'Set new shift in \;-qdV_JB  
        op.Type = "ShiftZ" >B0D/:R9  
        op.val1 = taq w|=gSC-o  
        op.parent = parID 'g]hmE  
        AddOperation eID, op $Z/klSEf  
        Print "Set aqueous humor thickness = " & taq-0.55 ,*7H|de7   
    2-~a P  
        '************************************************************************* Ejq=*UOP  
        'Radius and conic constant of anterior lens H6_xwuw:  
        '************************************************************************* B]1HS`*7  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ^"1TPd|  
        GetConic eID, entity, curv, conic hL0]R,t;'  
    Mec{_jiH&D  
        SetConic eID, entity, 1/Rant, CCant YZibi  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant M:_!w[NiLp  
    +O'vj  
        '************************************************************************* Qu`n&  
        'Radius and conic constant of posterior lens VMx%1^/(  
        '************************************************************************* 3w Z(+<4i  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) I0DM=V>;  
        GetConic eID, entity, curv, conic r=qLaPG  
    }'lNi^"XL  
        SetConic eID, entity, 1/Rpost, CCpost Uan,H1a   
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost v Xb:  
    NgHpIonC  
        '************************************************************************* p'&*r2_ram  
        'Lens thickness (Position of posterior lens surface) gv9=quG  
        '************************************************************************* 1i u =Y  
    PPa^o8jd  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Z v4<b  
    ;-Ss# &  
        ' Delete any z-shift(s) a\pi(9R  
        count = 0 ]M3# 3Ha"  
        While GetOperationCount(eID)>count >!}`%pk(  
            GetOperation eID, count, op ?vu_k 'io  
            If op.Type="ShiftZ" Then ^n9a " qz  
                DeleteOperation eID,count M/{g(|{  
                count=count-1 M-Y0xWs  
            End If x5OC;OQc  
            count=count+1 B;!f<"a8  
        Wend L,~MicgV  
    y? "@v.  
        'Set new z-shift [Uli>/%JB  
        op.Type = "ShiftZ" H?uukmZl  
        op.val1 = tlens ANMYX18M  
        op.parent = parID 2zK"*7b?  
        AddOperation eID, op jJ~Y]dQi  
        Print "Set lens thickness = " & tlens 3sFeP &  
    wVqd$nsY"  
        '************************************************************************* Kd3QqVJBz1  
        'Lens index of refraction }>&KUl  
        '************************************************************************* JDv-O&]  
        eID = FindMaterial( "Lens" ) t\r:E2 O  
        GetModelMaterial eID, mat .#fPw_i  
    <C<`J{X0  
        mat.Nd = nlens i"HgvBHx  
        SetModelMaterial eID, mat We}lx{E  
        Print "Set lens index of refraction = " & nlens |)o#|Qo  
    Q> 8pP\ho  
        '************************************************************************* aq Mc6N`z  
        'Pupil diameter $ [7 Vgs  
        '************************************************************************* R#(G%66   
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) @T&t.|`  
    H{V)g  
        'Adjust pupil diameter (trimming volume inner hole) s&'BM~WI  
    \k@Z7+&7  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ->E=&X  
    5| w&dM  
        ' Adjust pupil location to just in front of the lens #U=;T]!'$  
        parID = FindFullName( "Geometry.Arizona Eye" ) j7 d:v7+_  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) }q!_!q,@  
        count = 0 0xpx(T[  
        While GetOperationCount(eID)>count ip``v0Nf  
            GetOperation eID, count, op U,; xZe  
            If op.Type="ShiftZ" Then dvjTyX  
                DeleteOperation eID,count WM,i:P)b  
                count=count-1 A+ 0,i  
            End If d~*TIN8Ke~  
            count=count+1 /smiopFcq  
        Wend Lw*]EG|?  
        op.Type = "ShiftZ" u+D[_yd^  
        op.val1 = taq-0.01 Ct]A%=cZW  
        op.parent = parID /\=MBUN  
        AddOperation eID, op [VSU"AJY  
    RFko>d  
        Print "Set pupil diameter = " & pupilDiam _+w/ pS`M  
    7Kf}O6nE  
        'Update AZ Eye subassembly Description cDV ^8 R  
        eID = FindFullName( "Geometry.Arizona Eye" ) :0 ^s0l  
        GetEntity eID, entity 8o-bd_  
        entity.Description = "Accommodation = " & A & "D" O~@fXMthh  
        SetEntity eID, entity  k0H#:c}  
    c ~F dx  
        Update -<N&0F4|*  
        Print "DONE!" o a<q/  
         8#LJ*o  
    End Sub uQeu4$k!  
    QH@>icAb  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: $'"8QOnJ?k  
    ~}%~oT  
    Accommodation = 4 Diopters 1u}nm;3  
    Pupil Diameter = 4 mm vtxvS3   
    Set aqueous humor thickness = 2.81 2KI!af[I  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 m)&znLA  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 Ya Y8 `M{  
    Set lens thickness = 3.927 YQ(Po!NI\'  
    Set lens index of refraction = 1.42672 +S~.c;EK  
    Set pupil diameter = 4 IFuZ]CBz  
    DONE! "uD= KlA  
    6Nh0  
    P $ >`  
    QQ:2987619807 lCb+{OB  
     
    分享到