[技术]Arizona眼睛模型 [复制链接]

简介 \`x'g)z(i  
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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。 hR{Zh>  
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模型 ,iy   
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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。 |-<L :%  
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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. Z2 4 m  
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光源 Aed"J5[a  
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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。 sP7(1)\  
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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。 &n wg$z{Y  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 <hdCO< 0(  
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视网膜的散射 ualtIHXK)  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 hd' n"  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 /jAs`"U  
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脚本 u1l#k60  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： Ns_d10rZ.  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 *k -UQLJ  
余下的脚本计算与屈光度有关的所有参数。 hv6>3gbr  
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分析 K
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ns-x\B?^  
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脚本代码 _=b[b]Ec$s  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 2#!D"F  
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Dim entity As T_ENTITY jiat5  
Dim op As T_OPERATION R
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Dim mat As T_MODELMATERIAL o<y7Ut  
Dim A As Double QXCI+Fcg  
Dim pupilDiam As Double Qa=;Elp:[  
Dim eID As Long !VW#hc\A5  
Dim parID As Long o,L!F`W  
Dim count As Integer 7@\iBmr6  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double
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Dim tlens As Double, nlens As Double (Jm_2CN7X  
Dim curv As Double, conic As Double 3c)LBM  
Dim ok As Long 6O}r4*  
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Sub Main fXN;N&I  
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    '用户输入对话框 4s~o   
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 &AzA0r&,  
        TextBox 220,21,40,21,.TextBox1 'default: 0 X!m/I i$q  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 BmZd,}{  
        OKButton 40,91,90,21 d;z`xy(C  
        CancelButton 190,91,90,21 lPH]fWt<  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 Z`D#L[z$  
        TextBox 220,49,40,21,.TextBox2 'default: 4 TUT>*  
    End Dialog }.#C9<"}  
    Dim dlg As UserDialog xGqZ8v`v  
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    ok = Dialog (dlg) $ _zdjzT  
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    If ok=0 Then    'cancel button was pressed 2IGAZ%%  
        Print "Execution cancelled." B}vI<?c  
        End ?@ O[$9y  
    End If +XsY*$O  
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    'Assign accommodation and pupil diameter & use defaults if field left empty 
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    If dlg.TextBox1 = "" Then c7'Pzb)'  
        A = 0           'Default accommodation .gB#g{5+J  
    Else (g 8K?Q  
        A = CDbl(dlg.TextBox1) [mhY_Hmz]  
    End If XG0,
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    If dlg.TextBox2 = "" Then `Tab
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        pupilDiam = 4   'Default pupil diameter mesR)fTI  
    Else 8u>E(Vmpu  
        pupilDiam = CDbl(dlg.TextBox2) +m"iJW0  
    End If RtSk;U1  
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    Print " " {pVD`#Tl[  
    Print "Accommodation = " & A & " Diopters" _vad>-=D*U  
    Print "Pupil Diameter = " & pupilDiam & " mm" E@
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    ' Calculate new parameters with accommodation $Uzc  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness X{)M}WO+r  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens _:{XL c  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens )UWE.oBI  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens mFT[[Z#  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens c|E  
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    tlens = 3.767 + 0.04*A                  'Lens thickness b.$Gc!g  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction $Cte$jg{;  
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    'Adjust parameters to account for accommodation %hY+%^k.  
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    '************************************************************************* +&|WC2#  
    'Aqueous thickness (Position of Lens) 1<lLE1fk  
    '************************************************************************* J|s4c`=  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 55Jk "V#8  
    GetCustomElement eID, entity U|,VH-#  
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    parID = FindFullName( "Geometry.Arizona Eye" ) " 4s,a  
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    ' Delete any shift(s) in z S53[K/dZo  
    count = 0 d"$ \fL  
    While GetOperationCount(eID)>count F`'e/  
        GetOperation eID, count, op vQztD_bX%  
        If op.Type="ShiftZ" Then =8[HC}s|$  
            DeleteOperation eID,count >hHn{3y  
            count=count-1 -8g ;t3z  
        End If ]U]{5AA6  
        count=count+1 &FGz53fd4  
    Wend 7)~/`w)P  
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    'Set new shift in >pr{)bp G  
    op.Type = "ShiftZ" W*gu*H^s~  
    op.val1 = taq |Zz3X  
    op.parent = parID QO0T<V  
    AddOperation eID, op }56"4/ Z  
    Print "Set aqueous humor thickness = " & taq-0.55 H=EvT'g  
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    '************************************************************************* Ju+r@/y%  
    'Radius and conic constant of anterior lens #AE'arT<  
    '************************************************************************* .BZw7 YV  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 87y$=eZ  
    GetConic eID, entity, curv, conic 9J*m!-hOY  
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    SetConic eID, entity, 1/Rant, CCant #}l}1^$  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant SxNs  

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    '************************************************************************* db4Ol=  
    'Radius and conic constant of posterior lens ,Epg&)wC]  
    '************************************************************************* (',G Ako  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) u JGYXlLE  
    GetConic eID, entity, curv, conic XswEAz0=  
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    SetConic eID, entity, 1/Rpost, CCpost [[ HXOPaV  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ^<7)w2ns  
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    '************************************************************************* }B^KV#_{S  
    'Lens thickness (Position of posterior lens surface) Jy{A1i@4~s  
    '************************************************************************* a'rN&*P  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) qVx0VR1:  
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    ' Delete any z-shift(s) =D<46T=(RB  
    count = 0 Ay/ "2pDZ  
    While GetOperationCount(eID)>count ~\(U&2t  
        GetOperation eID, count, op =k'3rm*ld  
        If op.Type="ShiftZ" Then 0; M+8  
            DeleteOperation eID,count ?E=&LAI#  
            count=count-1 tNoo3&  
        End If w*OZ1|  
        count=count+1 3;@t{rIin  
    Wend Wl?*AlFlk  
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    'Set new z-shift 7{2knm^  
    op.Type = "ShiftZ" 52,pCyU  
    op.val1 = tlens ma?$@]`k  
    op.parent = parID 4L(axjMYU  
    AddOperation eID, op mM&H;W  
    Print "Set lens thickness = " & tlens
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    '************************************************************************* s'J8E+&5  
    'Lens index of refraction \|L@  
    '************************************************************************* A !x"*  
    eID = FindMaterial( "Lens" ) eOE7A'X  
    GetModelMaterial eID, mat A!x_R {,yH  
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    mat.Nd = nlens >x eKO2o  
    SetModelMaterial eID, mat L Lm{:T7  
    Print "Set lens index of refraction = " & nlens ?S36)oZzg  
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    '************************************************************************* i\XOk!  
    'Pupil diameter 3W5|Y@0  
    '************************************************************************* % Lhpj[C  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) GTyS8`5E*  
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    'Adjust pupil diameter (trimming volume inner hole) { %vX/Ek  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" (&=-o(  
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    ' Adjust pupil location to just in front of the lens 5rr7lwWZ  
    parID = FindFullName( "Geometry.Arizona Eye" ) ]3BTL7r  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) =hH>]$J[  
    count = 0 y4tM0h  
    While GetOperationCount(eID)>count ;^^u_SuH  
        GetOperation eID, count, op Hl8-1M$&  
        If op.Type="ShiftZ" Then b54<1\&  
            DeleteOperation eID,count n{6XtIoYq  
            count=count-1 s*>s;S?{|  
        End If *RD9gIze  
        count=count+1 [-x~Q[  
    Wend P>+{}c}3I  
    op.Type = "ShiftZ" be|k"s|6)  
    op.val1 = taq-0.01 MS)#S&  
    op.parent = parID h/?8F^C#v  
    AddOperation eID, op 47ppyh6@  
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    Print "Set pupil diameter = " & pupilDiam ),(ejRP'r  
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    'Update AZ Eye subassembly Description EW%%W6O6  
    eID = FindFullName( "Geometry.Arizona Eye" ) `(vgBz`e[  
    GetEntity eID, entity O[+S/6uy  
    entity.Description = "Accommodation = " & A & "D" +y!dU{L^  
    SetEntity eID, entity j7K9T  
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    Update Ek~Qp9B  
    Print "DONE!" r :{2}nE  
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End Sub 5)+(McJC  
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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： [ dpd-s  
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Accommodation = 4 Diopters gbL99MZ@~  
Pupil Diameter = 4 mm (YVl5}V  
Set aqueous humor thickness = 2.81 \bw71( Q  
Set anterior lens radius = 10.4 and conic constant = -2.375869 S7N3L."  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 hZ Gr/5f  
Set lens thickness = 3.927 2f9~:.NgF  
Set lens index of refraction = 1.42672 #O6SEK|Z  
Set pupil diameter = 4  kj~)#KDN  
DONE! (cAv :EKpo