[技术]Arizona眼睛模型 [复制链接]

简介 ftb .CPWI  
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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。 D(;jv="/  
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模型 VQ R E]  
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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。 ,`pUz[wl  
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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. \CU-a`n  
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光源 /f*QxNZ,p  
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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。 ts:YJAu+F  
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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。 E%b*MU  
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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。 N,3 )`Vm  
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视网膜的散射 Nx;Oz  
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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。 , 3&DA  
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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。 O}-+o1  
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脚本 Xk(p:^ R  
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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： Mp3nR5@d$  
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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。 v.6K;TY.  
余下的脚本计算与屈光度有关的所有参数。 Vv&GyqoO]  
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分析 j,79G^/YG  
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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`X}
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脚本代码 4*&2D-8<K  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. U?xa^QVhj  
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Dim entity As T_ENTITY v05$"Ig  
Dim op As T_OPERATION NydF'N_1  
Dim mat As T_MODELMATERIAL Oj>;[O"  
Dim A As Double Tl L,dPM  
Dim pupilDiam As Double RZ0+Uu/J  
Dim eID As Long AQGl}%k_  
Dim parID As Long b?j\YX[e  
Dim count As Integer v=~+o[  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double d$HPpi1LL  
Dim tlens As Double, nlens As Double #2dH2k\F  
Dim curv As Double, conic As Double f~?kx41dq  
Dim ok As Long xz-?sD/xe  
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Sub Main y-uSpW  
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    '用户输入对话框 Hyb_>n  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 f&I5bPS7}  
        TextBox 220,21,40,21,.TextBox1 'default: 0 48)D%867.;  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 cDq*B*e  
        OKButton 40,91,90,21 eyuQ}
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        CancelButton 190,91,90,21 ;TL>{"z`x  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 6f^IAa|  
        TextBox 220,49,40,21,.TextBox2 'default: 4 +yxL}=4s  
    End Dialog kA/yL]m^S  
    Dim dlg As UserDialog {n{-5Y  
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    ok = Dialog (dlg) i|x
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    If ok=0 Then    'cancel button was pressed 0*,]`A=  
        Print "Execution cancelled." GK[9Cm"v  
        End l\
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    End If ~?Zm3zOCc2  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 9vBW CCf
 
    If dlg.TextBox1 = "" Then H`4KhdqR
 
        A = 0           'Default accommodation };g<|v*o  
    Else _Mi*Fvj  
        A = CDbl(dlg.TextBox1) qS?^(Vt|R  
    End If A}[x))r  

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    If dlg.TextBox2 = "" Then J;N\q  
        pupilDiam = 4   'Default pupil diameter L0qL\>#ejr  
    Else Q[9W{l+  
        pupilDiam = CDbl(dlg.TextBox2)  = Atyy  
    End If eMtQa;Lc9o  
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    Print " " ZyV^d3F@$  
    Print "Accommodation = " & A & " Diopters" +o]J0Gu  
    Print "Pupil Diameter = " & pupilDiam & " mm" GHQm$|3I  
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    ' Calculate new parameters with accommodation !$p E=~1C  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness kBtzJ#j
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens -YS9u[   
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens PnH5[4&k  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens -PaR&0Tt  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ~&WBA]w'+  
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    tlens = 3.767 + 0.04*A                  'Lens thickness w& )ApfL  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction esd9N'.Q*  
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    'Adjust parameters to account for accommodation ^*F'[!. p  
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    '************************************************************************* or(P?Ro  
    'Aqueous thickness (Position of Lens) v!#koqd1y.  
    '************************************************************************* SmV}Wf  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) $U'*}S  
    GetCustomElement eID, entity 'M fVZho{  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ZQyXzERp  
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    ' Delete any shift(s) in z ~BgNMO;|  
    count = 0 SqVh\Nn  
    While GetOperationCount(eID)>count :ay`Id_tm  
        GetOperation eID, count, op T3t w.yh  
        If op.Type="ShiftZ" Then 7)BK&kpVr  
            DeleteOperation eID,count [f?x
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            count=count-1 |Ew&.fgz  
        End If Y]Zp[!  
        count=count+1 |AS9^w  
    Wend {(Ba  
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    'Set new shift in =c
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    op.Type = "ShiftZ" 'JJ :  
    op.val1 = taq :q$.=?X3  
    op.parent = parID a[J_
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    AddOperation eID, op 4 ;^  
    Print "Set aqueous humor thickness = " & taq-0.55 .#LHj}u  
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    '************************************************************************* Vg7BK%  
    'Radius and conic constant of anterior lens ,D'bIk  
    '************************************************************************* -ug-rdXV  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) #(-?i\i  
    GetConic eID, entity, curv, conic 58]t iP"  
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    SetConic eID, entity, 1/Rant, CCant ODKS6E1{  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant gyobq'o-  
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    '************************************************************************* >[g.8'hI  
    'Radius and conic constant of posterior lens L"}2Y3
 
    '************************************************************************* cUwR6I9  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) T!|-dYYI  
    GetConic eID, entity, curv, conic ygxaT"3"=  
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    SetConic eID, entity, 1/Rpost, CCpost r|3<UR%  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost twp~#s:\z  
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    '************************************************************************* Ju_(,M-Vgr  
    'Lens thickness (Position of posterior lens surface) \7Fp@ .S3  
    '************************************************************************* US&:UzI.  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) zS `>65}e  
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    ' Delete any z-shift(s) 21hTun"W  
    count = 0 ;JX2ebx  
    While GetOperationCount(eID)>count A6#v6iT  
        GetOperation eID, count, op JR|P
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        If op.Type="ShiftZ" Then Agwl2AM5k  
            DeleteOperation eID,count L/,M@1@R  
            count=count-1 tw<}7l_>Au  
        End If UbP$WIrq  
        count=count+1 q]v{o8:U  
    Wend :-j/Y'H_  
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    'Set new z-shift u9{Z*w3L7  
    op.Type = "ShiftZ" (n2=.9k!  
    op.val1 = tlens 1(/rg  
    op.parent = parID `LJ.NY pP  
    AddOperation eID, op FwDEYG  
    Print "Set lens thickness = " & tlens (!T\[6  
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    '************************************************************************* MYUL y2)  
    'Lens index of refraction `'ak/%Krh  
    '************************************************************************* 7qg. :h  
    eID = FindMaterial( "Lens" ) $~T|v7Y%  
    GetModelMaterial eID, mat nW]T-!  
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    mat.Nd = nlens T>m|C}yy  
    SetModelMaterial eID, mat dEfP272M  
    Print "Set lens index of refraction = " & nlens |qb-iXW=  
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    '************************************************************************* 9iGp0_J  
    'Pupil diameter BsYJIKfW  
    '************************************************************************* -V:7j8  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 8VMD304  
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    'Adjust pupil diameter (trimming volume inner hole) 0~cbB  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" lv&
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    ' Adjust pupil location to just in front of the lens #|6M*;lN|  
    parID = FindFullName( "Geometry.Arizona Eye" ) )"s(
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) - S%8  
    count = 0 BSg3  
    While GetOperationCount(eID)>count IR"=8w#MP  
        GetOperation eID, count, op f:h<tlob  
        If op.Type="ShiftZ" Then ?YnB:z*eV  
            DeleteOperation eID,count G V%@A  
            count=count-1 U zMIm  
        End If ,>3|\4/Q  
        count=count+1 Uy$?B"Z  
    Wend SoB6F9  
    op.Type = "ShiftZ" !p3vnOX6  
    op.val1 = taq-0.01 8&v%>wxR@  
    op.parent = parID G\ /L.T  
    AddOperation eID, op fCi1JH;  
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    Print "Set pupil diameter = " & pupilDiam 7G23D  
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    'Update AZ Eye subassembly Description CK1gzIg>  
    eID = FindFullName( "Geometry.Arizona Eye" ) iuEQ?fp  
    GetEntity eID, entity vtXZ`[D,l)  
    entity.Description = "Accommodation = " & A & "D" ljjnqQ%  
    SetEntity eID, entity EV N:3  
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    Update ;V4f6[<]'z  
    Print "DONE!" tnC,1HV0[  
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End Sub "@@Z{  
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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： =kn-F T  
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Accommodation = 4 Diopters hi9@U]H#  
Pupil Diameter = 4 mm p}h9>R  
Set aqueous humor thickness = 2.81 O-]^_LV`  
Set anterior lens radius = 10.4 and conic constant = -2.375869 %s[ n2w  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 \_3#%%z  
Set lens thickness = 3.927 TRQH{O\O  
Set lens index of refraction = 1.42672 )[5.*g@  
Set pupil diameter = 4 F6-U{+KU$!  
DONE! [HQ Bx`3TS