[分享]Arizona眼睛模型 [复制链接]

简介 M8lw; (  
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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。 .XpuD,^;@  
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模型 KyIUz9$  
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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。 USART}Us4  
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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. ")ys!V9  
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光源 Jd `Qa+  
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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。 CeU=A9  
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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。 ;/NC[:'$D  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 Z<<=2Xl(  
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视网膜的散射 7.2G}O6$  
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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。 ;E{jn4B'  
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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。 eSIG+{;&  
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脚本 )cL(()N  
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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：  &I-T  
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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。 6?lAbW  
余下的脚本计算与屈光度有关的所有参数。 W4.w  
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分析 Fa`%MR1  
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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。 Y8%l)g  
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脚本代码 iM7^  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 2aR9vmR  
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Dim entity As T_ENTITY U<F|A!Fg  
Dim op As T_OPERATION [< g9jX5  
Dim mat As T_MODELMATERIAL oM>UIDCY_v  
Dim A As Double 3H<%\SYp  
Dim pupilDiam As Double gT+wn-3  
Dim eID As Long i@D4bd9lR  
Dim parID As Long oR8'^G0<  
Dim count As Integer ->OVNmCB`+  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double EF$ASN
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Dim tlens As Double, nlens As Double >Mh\jt\  
Dim curv As Double, conic As Double `e;r$Vpd_  
Dim ok As Long t%e<]2-8  
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Sub Main du'`&{_/  
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    '用户输入对话框 'Qg!ww7O  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 -B/'ArOo]  
        TextBox 220,21,40,21,.TextBox1 'default: 0 [%yj' )R/  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 [;yH.wn#5  
        OKButton 40,91,90,21 _U LzA  
        CancelButton 190,91,90,21 }&L%c>  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 WZHw(BN{+  
        TextBox 220,49,40,21,.TextBox2 'default: 4 SAitufS  
    End Dialog 4 7mT  
    Dim dlg As UserDialog Ad,n+%"e  
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    ok = Dialog (dlg) $8(QBZq  
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    If ok=0 Then    'cancel button was pressed wC%qSy'  
        Print "Execution cancelled." Vg,nNa3  
        End WC=d@d)M  
    End If i?b9zn
  
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    'Assign accommodation and pupil diameter & use defaults if field left empty yEjiMtQll]  
    If dlg.TextBox1 = "" Then 21Dc.t{  
        A = 0           'Default accommodation fwA8=oSZd  
    Else 8oI|Z=  
        A = CDbl(dlg.TextBox1) ;!VxmZ:j[  
    End If K/Pw;{}  
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    If dlg.TextBox2 = "" Then ig YYkt  
        pupilDiam = 4   'Default pupil diameter NZZy^p&O  
    Else |,=^P`#%  
        pupilDiam = CDbl(dlg.TextBox2) : qK-Rku  
    End If hi$AZ+  
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    Print " " iFI+W<QR  
    Print "Accommodation = " & A & " Diopters" _x""-X~OL  
    Print "Pupil Diameter = " & pupilDiam & " mm" &L+.5i  
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    ' Calculate new parameters with accommodation }.'rhR+  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness (y6}xOa(  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens {PxFG<^U  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens k]$oir  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens f@hM^%  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens \X\f~CB  
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    tlens = 3.767 + 0.04*A                  'Lens thickness iSoQ1#MP)2  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction "9c=kqkX  
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    'Adjust parameters to account for accommodation VZr:yE  
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    '************************************************************************* R)*DkL!  
    'Aqueous thickness (Position of Lens) N8Zz6{rp  
    '************************************************************************* GrJLQO0$N  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) [|c%<|d2  
    GetCustomElement eID, entity 6YNL4HE?  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ,>b>I#{  
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    ' Delete any shift(s) in z +e2:?d@  
    count = 0 [(3s5)O  
    While GetOperationCount(eID)>count ^Z;zA@[wt  
        GetOperation eID, count, op j:'g*IxM_  
        If op.Type="ShiftZ" Then K
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            DeleteOperation eID,count 'n-y*f  
            count=count-1 v ;}s`P\"  
        End If MaHP):~  
        count=count+1 _ pz}  
    Wend n6WKk+  
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    'Set new shift in K6-M.I  
    op.Type = "ShiftZ" 
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    op.val1 = taq 4L8hn4F
 
    op.parent = parID egG<"e*W}N  
    AddOperation eID, op T#3@r0M  
    Print "Set aqueous humor thickness = " & taq-0.55 xR3$sA2  
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    '************************************************************************* -c0ypz  
    'Radius and conic constant of anterior lens 7g"u)L&32  
    '************************************************************************* z dgS@g  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Lm2!<<<  
    GetConic eID, entity, curv, conic $+7uB-KsU  
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    SetConic eID, entity, 1/Rant, CCant f!#!  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Px=@Tw N,  
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    '************************************************************************* thJ~* 0^  
    'Radius and conic constant of posterior lens ZzupK^5Z  
    '************************************************************************* 2,q*[Kh1  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) edq,:  
    GetConic eID, entity, curv, conic 18Y#=uH}  
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    SetConic eID, entity, 1/Rpost, CCpost :+PE1=v  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost s b;q)Rh  
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    '************************************************************************* A'KH_])  
    'Lens thickness (Position of posterior lens surface) ,?|$DY+=  
    '************************************************************************* yzhNl'Rz  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) vW=L{8zu  
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    ' Delete any z-shift(s) <ErX<(0`ig  
    count = 0 I} jgz  
    While GetOperationCount(eID)>count MY@&^71i4  
        GetOperation eID, count, op zd=O;T;.  
        If op.Type="ShiftZ" Then _rwJ:r  
            DeleteOperation eID,count RTm/-6[N  
            count=count-1  L\PmT  
        End If c[,h|~K/_?  
        count=count+1 2aM7zP[Z  
    Wend u##th8h4U  
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    'Set new z-shift E7
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    op.Type = "ShiftZ" cQK-Euum  
    op.val1 = tlens :D)
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    op.parent = parID A#=TR_@:  
    AddOperation eID, op Mu?|<#s  
    Print "Set lens thickness = " & tlens @vt.Db  
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    '************************************************************************* hGz_F/  
    'Lens index of refraction 'k X8}bx  
    '************************************************************************* (.ir"\k1(  
    eID = FindMaterial( "Lens" ) =:^aBN#  
    GetModelMaterial eID, mat \_ 3>v5k|  
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    mat.Nd = nlens Dw%'u'HG  
    SetModelMaterial eID, mat by/H:
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    Print "Set lens index of refraction = " & nlens  yfZNL?2x  
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    '************************************************************************* x=oV!x  
    'Pupil diameter -&5YRfr!  
    '************************************************************************* ^viabkf C  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) mn/)_1'
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    'Adjust pupil diameter (trimming volume inner hole) VVas>/0qr  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" U)/.wa>  
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    ' Adjust pupil location to just in front of the lens 8W\yM;'  
    parID = FindFullName( "Geometry.Arizona Eye" ) hx:q@[ +J/  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) }Kp!,  
    count = 0 8=`L#FkRp  
    While GetOperationCount(eID)>count p0Jr{hM  
        GetOperation eID, count, op Q/+`9z+c  
        If op.Type="ShiftZ" Then Jb QK$[z"  
            DeleteOperation eID,count 8s1nE_3  
            count=count-1 rAH!%~  
        End If F8f}PV]b  
        count=count+1 1RRE{]2v#  
    Wend Ie.*x'b?y  
    op.Type = "ShiftZ" y[8;mCh  
    op.val1 = taq-0.01 wFJf"@/vJ  
    op.parent = parID >h\y1IrAaG  
    AddOperation eID, op 1<YoGm&  
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    Print "Set pupil diameter = " & pupilDiam YB38K(  
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    'Update AZ Eye subassembly Description ZL( j5E  
    eID = FindFullName( "Geometry.Arizona Eye" ) oac)na:O#  
    GetEntity eID, entity 'Gy`e-yB  
    entity.Description = "Accommodation = " & A & "D" ?jmP]MM  
    SetEntity eID, entity 0q}i5%m7  
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    Update uX_H;,n  
    Print "DONE!" 5G
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End Sub Er;/zxg9p  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： e"E8BU  
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Accommodation = 4 Diopters !eW1d0n'+f  
Pupil Diameter = 4 mm +fP.Ewi  
Set aqueous humor thickness = 2.81 ;TAj;Tf]H  
Set anterior lens radius = 10.4 and conic constant = -2.375869 G4* LO  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 pbH!u+DF  
Set lens thickness = 3.927 b] 5weS-<  
Set lens index of refraction = 1.42672 h `Lr5)B'  
Set pupil diameter = 4 3s6obw$ki  
DONE! 7%*#M#
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