[技术]Arizona眼睛模型 [复制链接]

简介 8}\"LXRbo  
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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。 `bC_J,>_  
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模型 N7#GK]n%/}  
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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。 OClY,@  
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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. NM]6 o  
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光源 @pkozE-  
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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。 3 oWCQ  
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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。 &FanD  
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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。 )O&$-4gL'  
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视网膜的散射 JqZ%*^O  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 Kc{wv/6}T  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 yi%B5KF~Al  
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脚本 <St`"H  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： k4l72 'P  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 lubS{3<  
余下的脚本计算与屈光度有关的所有参数。 '\;tmD"N5#  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 I'j?
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脚本代码 X3>(K1  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 3A9|{Vaz+6  
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Dim entity As T_ENTITY 0jyokER  
Dim op As T_OPERATION 5Tu.2.)N  
Dim mat As T_MODELMATERIAL _\<M58/z  
Dim A As Double qnlj~]NV  
Dim pupilDiam As Double JSL3.J  
Dim eID As Long Mu%'cwp$  
Dim parID As Long YUH/t
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Dim count As Integer #-`lLI:w0  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double <eI;Jph5  
Dim tlens As Double, nlens As Double kDKpuA!  
Dim curv As Double, conic As Double yqU++;6  
Dim ok As Long N$+"zJmw&  
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Sub Main ~DD/\V  
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    '用户输入对话框 pqe tYu  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 g,;MV7yE  
        TextBox 220,21,40,21,.TextBox1 'default: 0 F, "x~C  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 : ?V;  
        OKButton 40,91,90,21 6IX!9I\sT  
        CancelButton 190,91,90,21 We ->d |=  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 fS~.K9  
        TextBox 220,49,40,21,.TextBox2 'default: 4 $1
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    End Dialog 40<&0nn  
    Dim dlg As UserDialog r~TT c)2  
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    ok = Dialog (dlg) t'J fiGM  
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    If ok=0 Then    'cancel button was pressed QJ>>&`{,  
        Print "Execution cancelled." piP8ObGjy  
        End TU/J]'))C  
    End If r)t^qhn  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 9ZBF1sMg  
    If dlg.TextBox1 = "" Then r>Ln*R,9D  
        A = 0           'Default accommodation )>fi={!=c  
    Else pR"qPSv'  
        A = CDbl(dlg.TextBox1) Y[!a82MTzn  
    End If >=V+X"\Z  
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    If dlg.TextBox2 = "" Then p{rS -`I  
        pupilDiam = 4   'Default pupil diameter p[b\x_0%c  
    Else Q-F9oZ*0  
        pupilDiam = CDbl(dlg.TextBox2) ,:`6x[ +  
    End If 1 XG-O  
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    Print " " U]|q4!WE  
    Print "Accommodation = " & A & " Diopters" 'm|m+K83  
    Print "Pupil Diameter = " & pupilDiam & " mm" :~(im
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    ' Calculate new parameters with accommodation >-P0wowL  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness zqh{=&Tjx  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens sD8S2  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens lIz_0rE  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens =FmU]DV  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens =@2V#X]M*  
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    tlens = 3.767 + 0.04*A                  'Lens thickness %'e(3;YI  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Q(UGwd1  
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    'Adjust parameters to account for accommodation Ct)MvZ  
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    '************************************************************************* j;)g+9`  
    'Aqueous thickness (Position of Lens) iI*7WO[W  
    '************************************************************************* iIE(zw)H  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) :,m)D775S  
    GetCustomElement eID, entity -`OR6jd  
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    parID = FindFullName( "Geometry.Arizona Eye" ) >Mw &Tw}o  
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    ' Delete any shift(s) in z (x qA.(F  
    count = 0 SbZt\a 8  
    While GetOperationCount(eID)>count 7X(]r1-+\  
        GetOperation eID, count, op {yR)}r  
        If op.Type="ShiftZ" Then xV#a(>-4  
            DeleteOperation eID,count n*Vd<m;w  
            count=count-1 N;'HR)  
        End If #OWs3$9  
        count=count+1 @@83PJFid  
    Wend ,
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    'Set new shift in wy{>gvqK  
    op.Type = "ShiftZ"  7E`(8i  
    op.val1 = taq R*Z]  
    op.parent = parID m> (h_j  
    AddOperation eID, op iIaT1i4t.  
    Print "Set aqueous humor thickness = " & taq-0.55 {X<4wxeTo  
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    '************************************************************************* q9Sz7_K  
    'Radius and conic constant of anterior lens 1G%PXrEj8  
    '************************************************************************* QO{=Wi-  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) JA(fam~{  
    GetConic eID, entity, curv, conic t3t0vWE<,  
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    SetConic eID, entity, 1/Rant, CCant 2BDan^:-Av  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant F,M"/hnPT  
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    '************************************************************************* =kh>s$We  
    'Radius and conic constant of posterior lens 6@q[tN7_^  
    '************************************************************************* N4mJU'_{  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) &4Con%YU[  
    GetConic eID, entity, curv, conic x$GsDV  
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    SetConic eID, entity, 1/Rpost, CCpost NOr <,  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost {R-82%X  
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    '************************************************************************* @f{_=~+  
    'Lens thickness (Position of posterior lens surface) Hp
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    '************************************************************************* 7B]:3M6d  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) u'i%~(:$\)  
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    ' Delete any z-shift(s) 6lmiMU&V  
    count = 0 wB>S\~i  
    While GetOperationCount(eID)>count y[p$/$bgC5  
        GetOperation eID, count, op f{Fe+iPc  
        If op.Type="ShiftZ" Then D!}K)T1~R  
            DeleteOperation eID,count 7~"(+f  
            count=count-1 Y^6[[vaj2  
        End If 5m^Hi}S_  
        count=count+1 U2V^T'Y[  
    Wend 
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    'Set new z-shift B9e.-Xaf  
    op.Type = "ShiftZ" :vK(LU0K  
    op.val1 = tlens pSQCT  
    op.parent = parID 8b 8\  
    AddOperation eID, op *i?rJH  
    Print "Set lens thickness = " & tlens 5BHOHw D{  
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    '************************************************************************* r|^lt7\  
    'Lens index of refraction C~{NKMeC/m  
    '************************************************************************* TTZ['HP oI  
    eID = FindMaterial( "Lens" ) _7lt(f[S  
    GetModelMaterial eID, mat Y:%m;b$]  
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    mat.Nd = nlens kqD*TJA  
    SetModelMaterial eID, mat 1iJ0Hut}d  
    Print "Set lens index of refraction = " & nlens `u#;MUg  
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    '************************************************************************* )d}H>Qx=  
    'Pupil diameter {jOzap|  
    '************************************************************************* | "Jx  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) aGB0-;.t7  
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    'Adjust pupil diameter (trimming volume inner hole) "($Lx  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" E+}GxFG-:  

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    ' Adjust pupil location to just in front of the lens %1\v7Xw{9  
    parID = FindFullName( "Geometry.Arizona Eye" ) B;z;vrrL  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) V(;55ycr  
    count = 0 ;Y'8:ncDn  
    While GetOperationCount(eID)>count GS ;HtUQ  
        GetOperation eID, count, op 7~wFU*P1  
        If op.Type="ShiftZ" Then }+Rgx@XZ\  
            DeleteOperation eID,count |*^8~u3J"  
            count=count-1 4>4V-m\  
        End If 5/B#)gm  
        count=count+1 +65oC x  
    Wend JFkN=YR8  
    op.Type = "ShiftZ" & u$(NbK  
    op.val1 = taq-0.01 Hp btj  
    op.parent = parID ePp[m zg6  
    AddOperation eID, op j)jCu ;`  
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    Print "Set pupil diameter = " & pupilDiam EKZA5J7kn  
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    'Update AZ Eye subassembly Description w4\BD&7V  
    eID = FindFullName( "Geometry.Arizona Eye" ) X=v~^8M7%  
    GetEntity eID, entity i@P9EU  
    entity.Description = "Accommodation = " & A & "D" )]%e  
    SetEntity eID, entity ?gLR<d_  
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    Update SQ}S4r  
    Print "DONE!" oW0gU?Rr)u  
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End Sub [6AHaOhR'  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： ,H>
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Accommodation = 4 Diopters L-#e?Y}$J
 
Pupil Diameter = 4 mm oJ^C]E  
Set aqueous humor thickness = 2.81 q75ky1^1:  
Set anterior lens radius = 10.4 and conic constant = -2.375869 r0>q%eM8  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 'KH lrmnr  
Set lens thickness = 3.927 cZqfz  
Set lens index of refraction = 1.42672 >Q; g0\I_  
Set pupil diameter = 4 qQ^d9EK'?~  
DONE! HmvsYP66