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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 .1ddv4Hk  
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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。 r#~K[qb  
    8&a_A:h  
    模型 *PB/iVH%6  
    *)PG-$6X&  
    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。 .S vyj  
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    Table 1. AZ眼睛模型的定义
    .Dv=p B,u  
    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. 3YTIH2z 5  
    $Qq_qTJu?G  
    光源 >rRf9wO1l  
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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。 F_PTMl=Q|J  
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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。 u_'nOle K  
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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。 jyjQzt >\  
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    图2. 字母F光源的设定方法光 YmCbxYa7  
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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 (n=Aa;  
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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。 g5TkD~w"  
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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。 :1BM=_WwI  
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    图5. 视网膜重点采样规格设定
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    脚本 yam}x*O\xn  
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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: fv5C!> t  
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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。 >e_%M5 0  
    余下的脚本计算与屈光度有关的所有参数。 0:PSt_33F  
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    分析 x,-S1[#X;  
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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。 n>T:2PQ3  
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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 ;&7,7 3!  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. wEK%T P4  
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    Dim entity As T_ENTITY Xvq^1Y?  
    Dim op As T_OPERATION l<n5gfJ  
    Dim mat As T_MODELMATERIAL \AHY[WKx  
    Dim A As Double Za9$Hh/X  
    Dim pupilDiam As Double xi.IRAZX  
    Dim eID As Long p70,\&@3  
    Dim parID As Long ~ ;XYwQ"  
    Dim count As Integer l-MxLcz  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double F1\`l{B,\  
    Dim tlens As Double, nlens As Double O*ImLR)i+s  
    Dim curv As Double, conic As Double Y@ObwKcG  
    Dim ok As Long m6eFXP1U  
    "kU>~~y,  
    Sub Main -3\7vpcdN  
    To">DOt  
        '用户输入对话框 UIz:=DJ  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 QjqBO+  
            TextBox 220,21,40,21,.TextBox1 'default: 0 +q l  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Y[h#hZ  
            OKButton 40,91,90,21 /'mrDb_ip  
            CancelButton 190,91,90,21 :TlAL# s&  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 NA=#> f+U%  
            TextBox 220,49,40,21,.TextBox2 'default: 4 6SV7\,2M  
        End Dialog #>" }q3RO  
        Dim dlg As UserDialog \a?K?v|8  
    ,zD_% ox  
        ok = Dialog (dlg) 76$*1jB  
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        If ok=0 Then    'cancel button was pressed q[Vi[b^F  
            Print "Execution cancelled." U>in2u 9  
            End y&y/cML?  
        End If \hrrPPD1z  
    5cgo)/3M@}  
        'Assign accommodation and pupil diameter & use defaults if field left empty qP&byEs"  
        If dlg.TextBox1 = "" Then .uBO  
            A = 0           'Default accommodation ):^ '/e  
        Else 3;y_qwA  
            A = CDbl(dlg.TextBox1) TR~|c|B  
        End If z;[gEA+I  
    %v_IX2'  
        If dlg.TextBox2 = "" Then {s,^b|I2#U  
            pupilDiam = 4   'Default pupil diameter eN2dy-0  
        Else (*MNox?w  
            pupilDiam = CDbl(dlg.TextBox2) wLY#dm  
        End If ]GQv4-y  
    D DQs42[  
        Print " " OI*ZVD)J  
        Print "Accommodation = " & A & " Diopters" KS b(R/T  
        Print "Pupil Diameter = " & pupilDiam & " mm" 1B6C<cL:sU  
    A%h~Z a  
        ' Calculate new parameters with accommodation ;]{{)dst  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness c6t2Q6zV  
    '!Hhd![\=|  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens 7AI3|Ts]p  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ``+c`F?5  
    P`p6J8}4  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens %)8d{1at  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens m dC`W&r  
    sS-W~u|C  
        tlens = 3.767 + 0.04*A                  'Lens thickness y+?=E g  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction kNRyOUy  
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        'Adjust parameters to account for accommodation T_uNF8Bh  
    5.O-(eSa0&  
        '************************************************************************* mPckf  
        'Aqueous thickness (Position of Lens) XIqv {w  
        '************************************************************************* tB GkRd!  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Yr5iZ~V$  
        GetCustomElement eID, entity SrdE>fNbs  
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        parID = FindFullName( "Geometry.Arizona Eye" ) T}V7SD.  
    D}mo\  
        ' Delete any shift(s) in z   YfTd  
        count = 0 4xv9a;fP  
        While GetOperationCount(eID)>count EfFj!)fz  
            GetOperation eID, count, op ]#vWKNv:;  
            If op.Type="ShiftZ" Then \nC5 ,Rz  
                DeleteOperation eID,count ^a086n  
                count=count-1 ;:AG2zE!  
            End If cC b>zI  
            count=count+1 =>HIF#jU  
        Wend ,D:iQDG^  
    yEE|e&#>  
        'Set new shift in 2~#ZO?jE6  
        op.Type = "ShiftZ" se~ *<5  
        op.val1 = taq 9+]ZH.(YE  
        op.parent = parID : [A?A4l  
        AddOperation eID, op D_O5k|-V  
        Print "Set aqueous humor thickness = " & taq-0.55 7J0 ^N7"o  
    7YMxr3F  
        '************************************************************************* 1f+*Tmc5]Q  
        'Radius and conic constant of anterior lens !}iL O0  
        '************************************************************************* %T3j8fC{s  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) -X`~;=m>U  
        GetConic eID, entity, curv, conic ;~}- AI-  
    b%=1"&JI:  
        SetConic eID, entity, 1/Rant, CCant \7|s$ XQ\  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant # rh0r`  
    zd?bHcW/h  
        '************************************************************************* c80 }1  
        'Radius and conic constant of posterior lens {;]uL`abi?  
        '************************************************************************* j09mI$2y67  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 1j oc<EI  
        GetConic eID, entity, curv, conic p5lR-G  
    O{;M6U8C\  
        SetConic eID, entity, 1/Rpost, CCpost  JA }S{  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost F@>w&A ~K  
    VFe-#"0ZO  
        '************************************************************************* Xulh.: N}  
        'Lens thickness (Position of posterior lens surface) )v*v  
        '************************************************************************* gg lNpzj  
    P Xyyyir{  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) |usnY  
    ~0VwF  
        ' Delete any z-shift(s) /V#MLPA  
        count = 0 0!3!?E <  
        While GetOperationCount(eID)>count wo,""=l  
            GetOperation eID, count, op Jm{As*W>  
            If op.Type="ShiftZ" Then F!z! :yp  
                DeleteOperation eID,count U92B+up-  
                count=count-1 E'S<L|A/  
            End If k#l'ko/X  
            count=count+1 5*G8W\ $  
        Wend =2ATqb"$w  
    NTpz)R  
        'Set new z-shift r?Ev.m  
        op.Type = "ShiftZ" ANA2S*r  
        op.val1 = tlens *X-~TC0 [  
        op.parent = parID / t%"Dh 8x  
        AddOperation eID, op kw*Cr/'*  
        Print "Set lens thickness = " & tlens #Pe\Z/  
    4aIlzaA  
        '************************************************************************* c]cO[T_gGa  
        'Lens index of refraction M]8eW  
        '************************************************************************* Q%gY.n{=  
        eID = FindMaterial( "Lens" ) hEdo,gF*  
        GetModelMaterial eID, mat 1CF7  
    ZI#SYEF6  
        mat.Nd = nlens C%x(`S^/  
        SetModelMaterial eID, mat  6Dr$*9  
        Print "Set lens index of refraction = " & nlens L!G9O]WB  
    7|{%CckN  
        '************************************************************************* l(0&6ENyj  
        'Pupil diameter <.y^  
        '************************************************************************* p ] $  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 9M-NItFos  
    NO0[`jy(  
        'Adjust pupil diameter (trimming volume inner hole) 37ri b  
    d-A%ZAkE]  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 0qaG#&!  
    -\sKSY5{R  
        ' Adjust pupil location to just in front of the lens g,z&{pZch  
        parID = FindFullName( "Geometry.Arizona Eye" ) ~gzpX,{ n  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) nvUkbmZG#  
        count = 0 Is,*qrl :  
        While GetOperationCount(eID)>count +Qb2LR  
            GetOperation eID, count, op 0SGczgg  
            If op.Type="ShiftZ" Then c'wU O3S  
                DeleteOperation eID,count 7W>}7  
                count=count-1 ' /@!"IXz  
            End If G`3vH,  
            count=count+1 =t>`< T|(  
        Wend .J7-4  
        op.Type = "ShiftZ" $F /p8AraK  
        op.val1 = taq-0.01 +kdU%Sm  
        op.parent = parID .+ yJh  
        AddOperation eID, op FdK R{dX}  
    ggYIq*4  
        Print "Set pupil diameter = " & pupilDiam c,u$tnE)  
    5qODS_Eq  
        'Update AZ Eye subassembly Description Zj /H3,7  
        eID = FindFullName( "Geometry.Arizona Eye" ) =f{Z~`3  
        GetEntity eID, entity \-`oFe"  
        entity.Description = "Accommodation = " & A & "D" A.'`FtV  
        SetEntity eID, entity =tvm=  
    ^PCL^]W  
        Update @_ tA"E  
        Print "DONE!" 5kL#V  
         J4R  
    End Sub ph|2lLZ  
    *rMN,B@  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: ^ _#gIT\  
    "~,(Xa3x  
    Accommodation = 4 Diopters CBgFB-!qpe  
    Pupil Diameter = 4 mm ?;r7j V/`j  
    Set aqueous humor thickness = 2.81 Q*{H]  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 ":#A>L? l  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 f@V{}&ZWp  
    Set lens thickness = 3.927 ^ 8Nr %NJ  
    Set lens index of refraction = 1.42672 e715)_HD  
    Set pupil diameter = 4 [4 (A458H  
    DONE! eVbh$cIrZ  
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    QQ:2987619807 [7t0[U~3?  
     
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