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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 9PKoNd^e  
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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。 *vRI)>wU  
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    模型 kPO6gdwq$  
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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。 ("?&p3];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. AbF(MK=i  
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    光源 ;v1NL@w*  
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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。 oQ%\[s$  
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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。 `S\zqF<  
    ;P;"F21^>  
    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。 0iJ!K;A2%  
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    图2. 字母F光源的设定方法光 ?GO SeV  
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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 1yBt/U2  
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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。 dn ZzA  
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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。 U@6jOZ  
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    图5. 视网膜重点采样规格设定
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    脚本 +VCo$o  
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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: jzs.+dAg  
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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。 S&4+ e:K  
    余下的脚本计算与屈光度有关的所有参数。 Kt W6AZJ  
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    分析 SY-ez 91  
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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。 :O $@shV  
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    图7. 字母F在视网膜上颜色分析
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    脚本代码 d2rL 8jW  
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    Option Explicit     'Remove this to enable non-dimensioned variables to be used. .'|mY$U~]  
    9W!8gCs  
    Dim entity As T_ENTITY 4YszVT-MU~  
    Dim op As T_OPERATION bfgz1 `u  
    Dim mat As T_MODELMATERIAL TQP+>nS,  
    Dim A As Double ha*X6R  
    Dim pupilDiam As Double Sd},_Kh  
    Dim eID As Long OJAx:&]3  
    Dim parID As Long CI`N8 f=v  
    Dim count As Integer 5Go0}'*%  
    Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double }e<'BIM E  
    Dim tlens As Double, nlens As Double ddsUz1%l  
    Dim curv As Double, conic As Double dY}pN"  
    Dim ok As Long GCT@o!  
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    Sub Main lT]=&m>  
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        '用户输入对话框 mjb { ~  
        Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 9tn;L"#&N  
            TextBox 220,21,40,21,.TextBox1 'default: 0 $5,~JYcb  
            Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 Sp:l;SGd  
            OKButton 40,91,90,21 Bv $UFTz  
            CancelButton 190,91,90,21 ]q{ PDZ   
            Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 $>*Yhz `  
            TextBox 220,49,40,21,.TextBox2 'default: 4 nnNv0 ?>d(  
        End Dialog t<nFy  
        Dim dlg As UserDialog #~^btL'dHF  
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        ok = Dialog (dlg) +$47v$p  
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        If ok=0 Then    'cancel button was pressed fN-Gk(Ic  
            Print "Execution cancelled." 38~PWKt  
            End n@!wp/J,  
        End If Z%}4bJ  
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        'Assign accommodation and pupil diameter & use defaults if field left empty -4w%Iy  
        If dlg.TextBox1 = "" Then d?A}qA[(  
            A = 0           'Default accommodation k=[pm5ZvT~  
        Else @%1IkvJV  
            A = CDbl(dlg.TextBox1) ;QBh;jg4  
        End If KOey8tB)1  
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        If dlg.TextBox2 = "" Then 2j&v;dmh<  
            pupilDiam = 4   'Default pupil diameter vJ"i.:Gf4  
        Else )%mg(O8uL  
            pupilDiam = CDbl(dlg.TextBox2) hQRL,?  
        End If /b5>Qp  
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        Print " " NjX[;e-u  
        Print "Accommodation = " & A & " Diopters" ExVDkt0  
        Print "Pupil Diameter = " & pupilDiam & " mm" gZO&r#   
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        ' Calculate new parameters with accommodation mdW~~-@H  
        taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness j8++R&1f]  
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        Rant = 12.0 - 0.4*A                     'Radius of anterior lens .2W"w)$nuq  
        CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens wpXgPVZT  
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        Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 4zjs!AK%  
        CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens p[9s<lEh  
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        tlens = 3.767 + 0.04*A                  'Lens thickness mM_ k ^4:  
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        nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ${I*nh>=  
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        'Adjust parameters to account for accommodation 0 Y>M=|  
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        '************************************************************************* D3D}DaEYj  
        'Aqueous thickness (Position of Lens) k GHQ`h  
        '************************************************************************* 8|@9{  
        eID = FindFullName( "Geometry.Arizona Eye.Lens" ) xb:&(6\F  
        GetCustomElement eID, entity rf.`h{!!  
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        parID = FindFullName( "Geometry.Arizona Eye" ) GIyF81KR 3  
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        ' Delete any shift(s) in z -TO\'^][X  
        count = 0 [;A[.&6  
        While GetOperationCount(eID)>count :nA.j"@  
            GetOperation eID, count, op !4(zp;WY^  
            If op.Type="ShiftZ" Then =-"c*^$]  
                DeleteOperation eID,count #wY0D_3@1  
                count=count-1 UAn&\8g_  
            End If L\%orLEmK  
            count=count+1 %<0eA`F4  
        Wend 5] 5 KB;  
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        'Set new shift in )G~w[~  
        op.Type = "ShiftZ" ?QZ"JX])  
        op.val1 = taq h6~$/`&]b  
        op.parent = parID >R\lqLILb,  
        AddOperation eID, op k D5!}+y  
        Print "Set aqueous humor thickness = " & taq-0.55 &V7M}@  
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        '************************************************************************* v{aq`uH  
        'Radius and conic constant of anterior lens b2,!g }I  
        '************************************************************************* zFz10pH  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 3^?ZG^V  
        GetConic eID, entity, curv, conic zZ=pP5y8  
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        SetConic eID, entity, 1/Rant, CCant #]P9b@@e  
        Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 2ZcKK8X;7  
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        '************************************************************************* \xv;sl$f  
        'Radius and conic constant of posterior lens e:'?*BYVg3  
        '************************************************************************* >J9oH=S6  
        eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) M_g ?<rK  
        GetConic eID, entity, curv, conic sEMQ  
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        SetConic eID, entity, 1/Rpost, CCpost Dre2J<QL  
        Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 9KWuN:Sg  
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        '************************************************************************* '2^7-3_1  
        'Lens thickness (Position of posterior lens surface) a.N{-2ptH  
        '************************************************************************* VTy9_~q  
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        parID = FindFullName( "Geometry.Arizona Eye.Lens" ) JjaoOe  
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        ' Delete any z-shift(s) AIMSX]m  
        count = 0 3?2 FP|G8  
        While GetOperationCount(eID)>count %`Z+a.~U  
            GetOperation eID, count, op b 5yW_Ozdh  
            If op.Type="ShiftZ" Then 7xRl9  
                DeleteOperation eID,count yY?b.ty  
                count=count-1 ls@i".[  
            End If ZKHG!`X0  
            count=count+1 (e(:P~Ry  
        Wend {9UEq0  
    8Nu=^[qwQM  
        'Set new z-shift #@<9S{F  
        op.Type = "ShiftZ" q$I:`&  
        op.val1 = tlens hGpv2>M  
        op.parent = parID ;rc`OZyE  
        AddOperation eID, op R2Zgx\VV'  
        Print "Set lens thickness = " & tlens dXF^(y]l  
    7}M2bH} \K  
        '************************************************************************* /|* Y2ETOr  
        'Lens index of refraction 93Co}@Y;Y+  
        '************************************************************************* '>r7V  
        eID = FindMaterial( "Lens" ) i3rH'B -I.  
        GetModelMaterial eID, mat Fu!RhsW5j  
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        mat.Nd = nlens &=VDASEu  
        SetModelMaterial eID, mat sI{ M  
        Print "Set lens index of refraction = " & nlens !pD*p)`s  
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        '************************************************************************* 'Lu__NfN  
        'Pupil diameter tH-C8Qxy  
        '************************************************************************* X5 j1`t,  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) yUpgoX(6  
    Q ]}Hd-  
        'Adjust pupil diameter (trimming volume inner hole) )wT-8o  
    EK4d_L]I  
        SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" #Y$hNQQ$F  
    J+`VujWT  
        ' Adjust pupil location to just in front of the lens 8ji_#og  
        parID = FindFullName( "Geometry.Arizona Eye" ) )jt #=9ZQ  
        eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Hv2De0W  
        count = 0 9I4K}R  
        While GetOperationCount(eID)>count x QIq^/F0  
            GetOperation eID, count, op {WYX~Mvvj  
            If op.Type="ShiftZ" Then E{|W(z,  
                DeleteOperation eID,count Q)IKOt;N]  
                count=count-1 %44leINx  
            End If +F^^c2E  
            count=count+1 97}OL`y  
        Wend 'Iw NTM  
        op.Type = "ShiftZ" H!$o$}A  
        op.val1 = taq-0.01 zx)z/1  
        op.parent = parID >k (C  
        AddOperation eID, op 0$ S8 fF@  
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        Print "Set pupil diameter = " & pupilDiam L U={")TdQ  
    mWsI}2  
        'Update AZ Eye subassembly Description !6*"(  
        eID = FindFullName( "Geometry.Arizona Eye" ) YB2VcF.LU  
        GetEntity eID, entity B!?%O  
        entity.Description = "Accommodation = " & A & "D" i%0ur}p  
        SetEntity eID, entity ~XO Ts  
    R}!:'^  
        Update AJF#Aw `o  
        Print "DONE!" /w}u3|L$  
         e]zBf;9 J  
    End Sub y ~U #veY  
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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: =Jyu4j *}  
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    Accommodation = 4 Diopters R8a3 1&  
    Pupil Diameter = 4 mm KV0]m^@x  
    Set aqueous humor thickness = 2.81 %`1q-,>v  
    Set anterior lens radius = 10.4 and conic constant = -2.375869 ZzJ?L4J5v  
    Set posterior lens radius = -4.424557 and conic constant = -3.081019 J^Wa8Q;9lX  
    Set lens thickness = 3.927 Yp^rR }N  
    Set lens index of refraction = 1.42672 P&*2pX:  
    Set pupil diameter = 4 K3#@SY j  
    DONE! dtRwTUMe?  
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    QQ:2987619807 $#9;)8J  
     
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