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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 +im>|  
    &F!Ct(c99  
    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。 kt0ma/QpP  
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    模型  3g#  
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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。 Y >83G`*}b  
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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. #7Pnw.s3zz  
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    光源 A%zX LV=3O  
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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。 S%sD#0l  
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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。 9Sy|:J0  
    |@+/R .l  
    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。 9c}mAg4  
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    图2. 字母F光源的设定方法光 z"vI-~,YU  
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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 /ZeN\ybx  
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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。 EJz?GM  
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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。 YIc|0[ ]*|  
    ]8c%)%Vi  
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    图5. 视网膜重点采样规格设定
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    脚本 L2jjkyX]  
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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: QR#L1+Hn  
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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。 3`mM0,fY  
    余下的脚本计算与屈光度有关的所有参数。 ~:ldGfb|  
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    分析 9bxBm  
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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$pUS{  
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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 ;GjZvo  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. R'Uw17I  
    '20SoVp  
    Dim entity As T_ENTITY ] C&AU[U*  
    Dim op As T_OPERATION 'ZUB:R@[  
    Dim mat As T_MODELMATERIAL 9eh9@~mU"l  
    Dim A As Double ^hN.FIzM  
    Dim pupilDiam As Double kYl')L6  
    Dim eID As Long L4x08 e  
    Dim parID As Long i"HENJyCb  
    Dim count As Integer ' thEZ  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double '/[9Xwh9  
    Dim tlens As Double, nlens As Double v Wt{kg;  
    Dim curv As Double, conic As Double kR1dk4I4  
    Dim ok As Long e+? -#  
    ,Q2?Z :l  
    Sub Main @#?w>38y  
    &|% F=/VU  
        '用户输入对话框 Vo; B#lK  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 pp!>:%  
            TextBox 220,21,40,21,.TextBox1 'default: 0 OfAh? ^R  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 [Dv6z t>  
            OKButton 40,91,90,21 VY#:IE:T  
            CancelButton 190,91,90,21 |rhCQ"H  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 $zR[2{bg  
            TextBox 220,49,40,21,.TextBox2 'default: 4 p^(gXzW  
        End Dialog bTrQ(qp  
        Dim dlg As UserDialog ,]\:]Y&?  
    '(4#He?Gd  
        ok = Dialog (dlg) M.loG4r!  
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        If ok=0 Then    'cancel button was pressed 1I1Z),  
            Print "Execution cancelled." 6 pQbh*  
            End \kQ@G  
        End If =64%eF  
    |9D;2N(&!  
        'Assign accommodation and pupil diameter & use defaults if field left empty zq?Iwyo  
        If dlg.TextBox1 = "" Then :AzP3~BI  
            A = 0           'Default accommodation ?#cX_  
        Else uINm>$G,5  
            A = CDbl(dlg.TextBox1) .AzGPcJY  
        End If $:aKb#l)  
    >d{O1by=d9  
        If dlg.TextBox2 = "" Then #G/ _FRo`  
            pupilDiam = 4   'Default pupil diameter L+b"d3!G&%  
        Else ?d? cD  
            pupilDiam = CDbl(dlg.TextBox2) |iJ+e -_R  
        End If _s&sA2r<  
    6$l6>A  
        Print " " x9Qa.Jmj  
        Print "Accommodation = " & A & " Diopters" hny):59f  
        Print "Pupil Diameter = " & pupilDiam & " mm" 2Y+8!4^L a  
    HVz,liq  
        ' Calculate new parameters with accommodation 8r 4 L4  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness s)e'}y  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens unUCn5hJ=  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens DW,fh8w  
    A)X 'We  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Mv O!p  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ,iUYsY  
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        tlens = 3.767 + 0.04*A                  'Lens thickness ];|;")#=  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction p(5'|eqBV  
    'aWzam>  
        'Adjust parameters to account for accommodation j(8I+||  
    1HBdIWhHv.  
        '************************************************************************* u}[Z=V  
        'Aqueous thickness (Position of Lens) ;zbF~5e  
        '************************************************************************* ~TGk`cAM>  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) n,Z B-"dW  
        GetCustomElement eID, entity m>@$T x  
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        parID = FindFullName( "Geometry.Arizona Eye" ) Xu1tN9:oE  
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        ' Delete any shift(s) in z 05<MsxB"w  
        count = 0 qX(sx2TK  
        While GetOperationCount(eID)>count bB^SD] }C  
            GetOperation eID, count, op ^c9~~m16+  
            If op.Type="ShiftZ" Then \\qw"w9  
                DeleteOperation eID,count y3 {om^ f  
                count=count-1 hE-u9i  
            End If }tIIA"dZ  
            count=count+1 d45JT?qg&  
        Wend <3!jra,h  
    ^[d|^fRH Q  
        'Set new shift in C?FUc cI  
        op.Type = "ShiftZ" Ef;OrE""  
        op.val1 = taq |7jUf$Q\p  
        op.parent = parID X3KP N  
        AddOperation eID, op ?hu$  
        Print "Set aqueous humor thickness = " & taq-0.55 Hm?zMyO.k  
    !V =s^8nj  
        '************************************************************************* az(u=}  
        'Radius and conic constant of anterior lens ak?XE4-N  
        '************************************************************************* pvJsSX  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) /&>6#3df-  
        GetConic eID, entity, curv, conic \h%/Cp+p  
    ~CQYF,[Th  
        SetConic eID, entity, 1/Rant, CCant H1,;Xrm  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant :VPZGzK4  
    B6gSt3w.  
        '************************************************************************* r lalr+Rf  
        'Radius and conic constant of posterior lens 0ih=<@1K  
        '************************************************************************* _RFTm.9&  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) pZ/aZg1Ld  
        GetConic eID, entity, curv, conic e+z_Rj%Y;I  
    :bLLN  
        SetConic eID, entity, 1/Rpost, CCpost xj/ +Z!,9  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost D]9I-|  
    uvK1gJrA)  
        '************************************************************************* !\a'GO[  
        'Lens thickness (Position of posterior lens surface) Cwxy ~.mI  
        '************************************************************************* F6gboo)SD  
    RZ!-,|"cwL  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 21$YZlhJ  
    {XMF26C#  
        ' Delete any z-shift(s) ;}b.gpG  
        count = 0 ZGHkW9b&  
        While GetOperationCount(eID)>count /q4<ZS#  
            GetOperation eID, count, op fA u^%jiU  
            If op.Type="ShiftZ" Then _MfB,CS  
                DeleteOperation eID,count slV+2b  
                count=count-1 'AX/?Srd  
            End If Uhc2`r#q  
            count=count+1 -{i;!XE$SR  
        Wend 6@-VLO))O  
    Y"&&=M#  
        'Set new z-shift QvK-3w;=  
        op.Type = "ShiftZ" %aU4d e^  
        op.val1 = tlens /jQW4eW0  
        op.parent = parID W6t"n_%?"  
        AddOperation eID, op /O1r=lv3Z  
        Print "Set lens thickness = " & tlens O_#Ag K<A  
    8[SiIuIV  
        '************************************************************************* ~3 Y)o|D3  
        'Lens index of refraction [XWY-q#Gg  
        '************************************************************************* 4tTK5`7N  
        eID = FindMaterial( "Lens" )  9x/HQ(1  
        GetModelMaterial eID, mat LlP_`fA  
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        mat.Nd = nlens , ;L  
        SetModelMaterial eID, mat  h&\%~LO.  
        Print "Set lens index of refraction = " & nlens P SDzs\s  
    KH)(xB=  
        '************************************************************************* ^w.x~#zI  
        'Pupil diameter PW"G]G,  
        '************************************************************************* 2]n"7Z8(v8  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) )A9K9pZj  
    [?mDTD8zU  
        'Adjust pupil diameter (trimming volume inner hole) XJ~_FiB  
    3A%/H`  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" *a*\E R  
    ;aKdRhDo  
        ' Adjust pupil location to just in front of the lens !8^:19+  
        parID = FindFullName( "Geometry.Arizona Eye" ) N.OC _H&  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 1>OfJc(K  
        count = 0 77- Jx`C  
        While GetOperationCount(eID)>count ?y82S*sb#  
            GetOperation eID, count, op c Q~}qE>I  
            If op.Type="ShiftZ" Then +!IIt {u  
                DeleteOperation eID,count %"~\Pu*>  
                count=count-1 U7d%*g  
            End If N"MuAUB:K  
            count=count+1 4:-h\%  
        Wend &K5wCNX1  
        op.Type = "ShiftZ" jy`jxOoG~Z  
        op.val1 = taq-0.01 jA R@?X  
        op.parent = parID 8munw  
        AddOperation eID, op mAh0xgm  
    _IJPZ'Hr  
        Print "Set pupil diameter = " & pupilDiam = R|?LOEK+  
    m RB-}  
        'Update AZ Eye subassembly Description YRF%].A%2  
        eID = FindFullName( "Geometry.Arizona Eye" ) ^~Nz8PCY  
        GetEntity eID, entity {7 &(2Z]z  
        entity.Description = "Accommodation = " & A & "D" K*Y.mM)  
        SetEntity eID, entity n.]K"$230  
    `T2RaWR4=  
        Update [OBj2=  
        Print "DONE!" 8`Fo^c=j  
         6%Ap/zvCZ>  
    End Sub ZzPlIl}\  
    rD)yEuYX  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: YXxaD@  
    ;u!qu$O  
    Accommodation = 4 Diopters !0:uM)_k  
    Pupil Diameter = 4 mm 9,=3D2x&  
    Set aqueous humor thickness = 2.81 I#QBJ#  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 k`Nc<nN8  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 AVyO5>w  
    Set lens thickness = 3.927 _hyboQi  
    Set lens index of refraction = 1.42672 =8S*t5  
    Set pupil diameter = 4 Xk%92Pto  
    DONE! J<Di2b+  
    `9rwu:3i  
    .C(Ir  
    QQ:2987619807 N*w/\|  
     
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