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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 OU#p^ 5K  
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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。 xWK/uE(  
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    模型 Eaxsg  
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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。 I\c7V~^hnG  
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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. Dr=$}Y  
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    光源 vZ57 S13  
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    多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 xaoR\H  
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    图1. 光源和提示信息使用
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    除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处,并增加了pre-propagation distance= -8。尽管光线在光瞳处创建,规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射,而不是在光瞳处入射。 AL,7rYZG$  
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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。 B)L0hi  
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    图2. 字母F光源的设定方法光 V mQ'  
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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 <%m1+%mA.  
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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。 cZ)mp`^n7  
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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。 6~2upy~e  
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    图5. 视网膜重点采样规格设定
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    脚本 _-543B}  
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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: yE,qLiH  
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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。 WcY_w`*L  
    余下的脚本计算与屈光度有关的所有参数。 Rf>)#hn%  
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    分析 )1Y?S;  
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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。 k0ai#3iJ  
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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 ]d7A|)q  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. >1Hv c7DP  
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    Dim entity As T_ENTITY %D:VcY9OC  
    Dim op As T_OPERATION oPni4^g i  
    Dim mat As T_MODELMATERIAL %,HUn`  
    Dim A As Double _xm<zy{`S  
    Dim pupilDiam As Double s2|.LmC3|B  
    Dim eID As Long =7H\llL4BC  
    Dim parID As Long kV T |(Y  
    Dim count As Integer dhnX\/  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 39 zfbxX  
    Dim tlens As Double, nlens As Double 6jgP/~hP>N  
    Dim curv As Double, conic As Double <Lxp t  
    Dim ok As Long 9*K-d'm  
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    Sub Main ~]d9 J  
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        '用户输入对话框 ^0}wmxDq  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 &S 66M2  
            TextBox 220,21,40,21,.TextBox1 'default: 0 4;AQ12<[1  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 m;{HlDez  
            OKButton 40,91,90,21 :A @f[Y'9  
            CancelButton 190,91,90,21 N wNxO  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 #5{xWMp/0  
            TextBox 220,49,40,21,.TextBox2 'default: 4 Z8Y& #cB  
        End Dialog }[UH1+`L  
        Dim dlg As UserDialog ]u$tKC  
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        ok = Dialog (dlg) U\qbr.<  
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        If ok=0 Then    'cancel button was pressed R13k2jLSQ  
            Print "Execution cancelled." o -)[{o\  
            End E#8|h(  
        End If &g23tT#P?  
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        'Assign accommodation and pupil diameter & use defaults if field left empty k \T]*A  
        If dlg.TextBox1 = "" Then Q%?%zuU  
            A = 0           'Default accommodation s[h;9 I1w  
        Else <X4f2z{T{@  
            A = CDbl(dlg.TextBox1) W5Pur lu?  
        End If aZ\Z7(  
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        If dlg.TextBox2 = "" Then @d|Sv1d%  
            pupilDiam = 4   'Default pupil diameter $V?sD{=W  
        Else 5WRqeSGh  
            pupilDiam = CDbl(dlg.TextBox2) MmvOyK NZF  
        End If 85[ 7lO)[  
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        Print " " 2 YWO'PL  
        Print "Accommodation = " & A & " Diopters" kJOZ;X=9/  
        Print "Pupil Diameter = " & pupilDiam & " mm" uaKbqX  
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        ' Calculate new parameters with accommodation w_@{v wM$A  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness H*3u]Ebh  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens Y:m8UnT  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens SC2LY  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Ti0kfjhX7  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens W|rAn2H  
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        tlens = 3.767 + 0.04*A                  'Lens thickness K3tW Y 4-  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction u^E0u^  
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        'Adjust parameters to account for accommodation =+T0[|gc(r  
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        '************************************************************************* G,Eh8 HboK  
        'Aqueous thickness (Position of Lens) ~~k0&mK|Q  
        '************************************************************************* d$+0 ;D4E  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) uTrzC+\aU  
        GetCustomElement eID, entity *9=}f;~  
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        parID = FindFullName( "Geometry.Arizona Eye" ) L1Yj9i  
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        ' Delete any shift(s) in z "10\y{`v^  
        count = 0 s%Ph  
        While GetOperationCount(eID)>count Yqo@ g2g  
            GetOperation eID, count, op }u0&>k|y  
            If op.Type="ShiftZ" Then 9 lG a*f)  
                DeleteOperation eID,count WpE "A  
                count=count-1 4Jc~I  
            End If MwSfuP  
            count=count+1 f8r7 SFwUv  
        Wend $/#[,1  
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        'Set new shift in l"X,[  
        op.Type = "ShiftZ" knV*,   
        op.val1 = taq  DQV9=  
        op.parent = parID eA?|X|  
        AddOperation eID, op p}gA8 o  
        Print "Set aqueous humor thickness = " & taq-0.55 3&M0@/  
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        '************************************************************************* b{-|q6  
        'Radius and conic constant of anterior lens ]qq2VO<b  
        '************************************************************************* Tl-%;X<X  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Rh ]XJM  
        GetConic eID, entity, curv, conic y>u |3:z  
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        SetConic eID, entity, 1/Rant, CCant ?LU>2!jN  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant OR+py.vK  
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        '************************************************************************* (0_zp`)  
        'Radius and conic constant of posterior lens u` (yT<>H  
        '************************************************************************* "66#F  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Nqd9)WQ  
        GetConic eID, entity, curv, conic 7u :kR;wk  
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        SetConic eID, entity, 1/Rpost, CCpost I7Abf7>*Q  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 1LvR,V<  
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        '************************************************************************* y[S9b (:+  
        'Lens thickness (Position of posterior lens surface) ^AOJ^@H^>  
        '************************************************************************* J#3[,~  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) mC0Dj O  
    u%"5<ll  
        ' Delete any z-shift(s) #NL'r99D/o  
        count = 0 RwrRN+&s\  
        While GetOperationCount(eID)>count 7,alZ"%W  
            GetOperation eID, count, op :1gpbfW  
            If op.Type="ShiftZ" Then #RSUChe7w  
                DeleteOperation eID,count H`q[!5~8  
                count=count-1 JlRNJ#h>  
            End If "<)Jso|  
            count=count+1 o :4#Ak S  
        Wend .We{W{  
    ZIh)D[n  
        'Set new z-shift UFj!7gX]  
        op.Type = "ShiftZ" ]\}MSo3  
        op.val1 = tlens UYW'pV  
        op.parent = parID C,LosAd  
        AddOperation eID, op eC6wrpZO  
        Print "Set lens thickness = " & tlens H<?s[MH[  
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        '************************************************************************* g\IwV+iDf  
        'Lens index of refraction ]TcQGW@'  
        '************************************************************************* ^%LyT!y  
        eID = FindMaterial( "Lens" ) EUV8H}d5  
        GetModelMaterial eID, mat @+y,E-YTdV  
    'W("s  
        mat.Nd = nlens Y Ztd IG  
        SetModelMaterial eID, mat JZ:yPvJ  
        Print "Set lens index of refraction = " & nlens 0B}2~}#  
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        '************************************************************************* #<u;.'R  
        'Pupil diameter C 'Y2kb  
        '************************************************************************* MtoOIkQ  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) !gfd!R  
    kh#fUAt  
        'Adjust pupil diameter (trimming volume inner hole) ^7=7V0>,:  
    N qz6_!  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" \ptjnwC^O  
    P46Q3EE  
        ' Adjust pupil location to just in front of the lens K" X" 2c1o  
        parID = FindFullName( "Geometry.Arizona Eye" ) [/n@BK  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) M#m;jJqON  
        count = 0 5nsoWqnE8  
        While GetOperationCount(eID)>count b&LAk-}[  
            GetOperation eID, count, op ?0+g.,9  
            If op.Type="ShiftZ" Then Un T\6u  
                DeleteOperation eID,count =1,1}OucP  
                count=count-1 ev_'.t'  
            End If iXvrZofE  
            count=count+1 ]H\tz@ &  
        Wend -R\dgS3  
        op.Type = "ShiftZ" MPw?HpM  
        op.val1 = taq-0.01 x7G*xHJ  
        op.parent = parID o[+t}hC[  
        AddOperation eID, op DGS,iRLnA  
    ?N!kYTR%}  
        Print "Set pupil diameter = " & pupilDiam 4fjwC,,  
    P*VZ$bUe5@  
        'Update AZ Eye subassembly Description ,_,*I/o>B  
        eID = FindFullName( "Geometry.Arizona Eye" ) ~oT*@  
        GetEntity eID, entity DL!%Np?`  
        entity.Description = "Accommodation = " & A & "D" ;ny9q  
        SetEntity eID, entity N>]J$[j  
    mo(>SnS<  
        Update v'S5F@ln  
        Print "DONE!" P~iZae  
         n&?)gKL0g  
    End Sub t*)mX2R,  
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    如果屈光度是4,光瞳直径是4,则会输出如下数据: v_WQ<G?  
    }N$f=:iI  
    Accommodation = 4 Diopters )58 ~2vR  
    Pupil Diameter = 4 mm WW &Wh<4  
    Set aqueous humor thickness = 2.81 P+OS  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 s;* UP   
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 ['sNk[-C  
    Set lens thickness = 3.927 gw[Eu>I  
    Set lens index of refraction = 1.42672 +{I" e,Nk  
    Set pupil diameter = 4 K :~tZ  
    DONE! BOq9\g`5s  
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    QQ:2987619807 w-LENdw  
     
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