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    [技术]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: 2021-10-22
    简介 [)M%cyQ  
    jyUjlYAAv`  
    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。  :D6 ON"6  
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    模型 p!7FpxZY  
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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。 KNvZm;Q6  
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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. >}8j+t&T  
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    光源 -`kW&I0  
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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。 wedbx00o  
    t7Iv?5]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。 !Vn\u  
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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。 qFCOUl  
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    图2. 字母F光源的设定方法光 KE5kOU;  
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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 3tIVXtUCUk  
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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。 /tx]5`#@7]  
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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。 A5I)^B<(  
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    图5. 视网膜重点采样规格设定
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    脚本 !&y8@MD15  
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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: u"cV%(#  
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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。 T= y}y  
    余下的脚本计算与屈光度有关的所有参数。 Cx@);4arj  
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    分析 )Pa'UGY  
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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。 r"3=44St  
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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 shy-Gu&  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. wY{-BuXv  
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    Dim entity As T_ENTITY TTX5EDCrC  
    Dim op As T_OPERATION Q2w_X8  
    Dim mat As T_MODELMATERIAL KEo ,m  
    Dim A As Double 7 UKh688  
    Dim pupilDiam As Double mUAi4N  
    Dim eID As Long 7?!d^$B  
    Dim parID As Long ?DS@e@lx  
    Dim count As Integer "yy5F>0Wt  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double bivuqKA  
    Dim tlens As Double, nlens As Double Drgv`z  
    Dim curv As Double, conic As Double 'A=^Se`=  
    Dim ok As Long ,GhS[VJjR  
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    Sub Main 9IdA%RM~mH  
    CAig ]=2'  
        '用户输入对话框 Fc)@,/R"v  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 HTv2#  
            TextBox 220,21,40,21,.TextBox1 'default: 0 }z'8Bu  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ~k-y &<UR  
            OKButton 40,91,90,21 p}z<Fdu 0  
            CancelButton 190,91,90,21 b4%??"&<Y  
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 W s3)gvpPA  
            TextBox 220,49,40,21,.TextBox2 'default: 4 xf\C|@i  
        End Dialog }1L4 "}L.  
        Dim dlg As UserDialog cN-?l7  
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        ok = Dialog (dlg) &T?RZ2  
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        If ok=0 Then    'cancel button was pressed c)6m$5]  
            Print "Execution cancelled." Gt8M&S-;  
            End :%_LpZ  
        End If RtkEGxw*^  
    '2A)}uR  
        'Assign accommodation and pupil diameter & use defaults if field left empty G/y5H;<9M  
        If dlg.TextBox1 = "" Then P[G)sA_"  
            A = 0           'Default accommodation "b~+;<}Q  
        Else ^&9zw\x;z  
            A = CDbl(dlg.TextBox1) #X+JHl  
        End If n$A9_cHF7  
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        If dlg.TextBox2 = "" Then Di,^%  
            pupilDiam = 4   'Default pupil diameter GLH0 ]  
        Else hIYNhZv  
            pupilDiam = CDbl(dlg.TextBox2) y;m|  
        End If H*?t^  
    @(EAq<5{  
        Print " " a Yg6H2Un  
        Print "Accommodation = " & A & " Diopters" Si4!R+4w  
        Print "Pupil Diameter = " & pupilDiam & " mm" 9R!atPz9  
    kP=eW_0D  
        ' Calculate new parameters with accommodation T= 80,  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness X~b X5b[P  
    ol\Utq,  
        Rant = 12.0 - 0.4*A                     'Radius of anterior lens W<h)HhyG  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens hk;5w{t}}  
    @Myo'{3vF  
        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens JMCKcZ%N  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens '0;l]/i.  
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        tlens = 3.767 + 0.04*A                  'Lens thickness rET\n(AJ  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction F>Ah0U0  
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        'Adjust parameters to account for accommodation i]c!~`  
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        '************************************************************************* ~Py`P'+  
        'Aqueous thickness (Position of Lens) B6+khuG(  
        '************************************************************************* GhAlx/K  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ~f2z]JLr:  
        GetCustomElement eID, entity V5@:#BIs  
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        parID = FindFullName( "Geometry.Arizona Eye" ) RXMISt3+{y  
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        ' Delete any shift(s) in z DaQ?\uq  
        count = 0 {S]}.7`l9(  
        While GetOperationCount(eID)>count nAAs{  
            GetOperation eID, count, op )N{Pw$l_  
            If op.Type="ShiftZ" Then /s&9SYF  
                DeleteOperation eID,count %@J.{@>  
                count=count-1 6D;Sgc5"  
            End If vQG5*pR*w  
            count=count+1 UkwP  
        Wend 3)wN))VBX  
    [C 7^r3w  
        'Set new shift in 94`7a<&ZNL  
        op.Type = "ShiftZ" )b L'[h  
        op.val1 = taq R{`(c/%8  
        op.parent = parID h%na>G  
        AddOperation eID, op W\$`w  
        Print "Set aqueous humor thickness = " & taq-0.55 FW;?s+Uyx  
    T9|m7  
        '************************************************************************* VOsR An/N  
        'Radius and conic constant of anterior lens Wx%H%FeK  
        '************************************************************************* ;3coP{  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ah$b [\#C  
        GetConic eID, entity, curv, conic .&iawz  
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        SetConic eID, entity, 1/Rant, CCant (62"8iD6  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant |)DGkOtd  
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        '************************************************************************* \[i1JG  
        'Radius and conic constant of posterior lens .[KrlfI  
        '************************************************************************* 5X$jl;6  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) tmYz R%i  
        GetConic eID, entity, curv, conic ;W )Y OT  
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        SetConic eID, entity, 1/Rpost, CCpost QD&`^(X1p  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ~8Fk(E_  
    )gUR@V>e2  
        '*************************************************************************  :A_@,Q  
        'Lens thickness (Position of posterior lens surface) =_*Zn(>t`  
        '************************************************************************* ?3`UbN:  
    Y=?3 js?O  
        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Xf]d. :  
    x_Y!5yg E  
        ' Delete any z-shift(s) :uS\3toj  
        count = 0 CI0C1/:@  
        While GetOperationCount(eID)>count |$Sedzj'  
            GetOperation eID, count, op Yx%Hs5}8  
            If op.Type="ShiftZ" Then V#$RR!X'  
                DeleteOperation eID,count h 0Q5-EA  
                count=count-1 '3tCH)s  
            End If ibk6|pp  
            count=count+1 7hcYD!DS  
        Wend f|c{5$N!  
    9ULQrq$?  
        'Set new z-shift ,AFu C <  
        op.Type = "ShiftZ" g}{aZ$sta  
        op.val1 = tlens :J@ gmY:C  
        op.parent = parID R4cM%l_#W  
        AddOperation eID, op c ( C%Hld  
        Print "Set lens thickness = " & tlens =z69e%.  
    n0 {i&[I~+  
        '************************************************************************* 6,"Q=9k4[  
        'Lens index of refraction :Yh+>c}N  
        '************************************************************************* L|xbR#v  
        eID = FindMaterial( "Lens" ) g-bK|6?yz  
        GetModelMaterial eID, mat I3I/bofz  
    ;bib/  
        mat.Nd = nlens 7(8;t o6(  
        SetModelMaterial eID, mat 5c0 ZRV#  
        Print "Set lens index of refraction = " & nlens Om\vMd@!  
    cp7=epho  
        '************************************************************************* Ya"a`ozq  
        'Pupil diameter zu{P#~21  
        '************************************************************************* J=I:CD%  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) >*_$]E  
    ,m:.-iy?  
        'Adjust pupil diameter (trimming volume inner hole) AjMh,@  
    IfAZn_  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ,T$U'&;  
    BM .~ 5\  
        ' Adjust pupil location to just in front of the lens Id .nu/  
        parID = FindFullName( "Geometry.Arizona Eye" ) WiR(;m<g  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) NP3y+s  
        count = 0 vMH  
        While GetOperationCount(eID)>count b9HtR-iR;  
            GetOperation eID, count, op %_W)~Pv{+  
            If op.Type="ShiftZ" Then f+,qNvBY/  
                DeleteOperation eID,count _op}1   
                count=count-1 )_S(UVI5  
            End If Fj3a.'  
            count=count+1 )U:m:cr<  
        Wend l4YJ c  
        op.Type = "ShiftZ" !ons]^km  
        op.val1 = taq-0.01 k2tF}  
        op.parent = parID 7WS p($  
        AddOperation eID, op 6}Ci>_i4#  
    jcf7n`L  
        Print "Set pupil diameter = " & pupilDiam ?X<eV1a   
    R"t,xM  
        'Update AZ Eye subassembly Description 04P}-L,  
        eID = FindFullName( "Geometry.Arizona Eye" ) e\zm7_+i{  
        GetEntity eID, entity CxW>~O:  
        entity.Description = "Accommodation = " & A & "D" j-}O0~Jz  
        SetEntity eID, entity plstZ,#j  
    mL{6L?  
        Update V5>B])yQ  
        Print "DONE!" 0 ZKx<]!  
         G}raA%  
    End Sub  |TH\`U  
     SRDp*  
    如果屈光度是4,光瞳直径是4,则会输出如下数据: 4p;`C  
    _8UU'1d  
    Accommodation = 4 Diopters vr6w^&[c^  
    Pupil Diameter = 4 mm \V~eVf;~  
    Set aqueous humor thickness = 2.81 >@_^fw)  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 *P=VFP  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 2eY_%Y0  
    Set lens thickness = 3.927 jLm ;ty2;  
    Set lens index of refraction = 1.42672 <<5(0#y#  
    Set pupil diameter = 4 N5 6g+,w%)  
    DONE! iz PDd{[  
     
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