[分享]Arizona眼睛模型 [复制链接]

简介 ~} 02q5H  
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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。 N!//m?}  
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模型 /u&7!>,  
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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。 cGSG}m@B`  
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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. JLbmh1'  
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光源 B/_~j_n$m  
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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。 ^H!45ph?Jc  
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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。 `J$7X  
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在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 =3Ohy,5L  
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视网膜的散射 p
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 ]P96-x  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 ]m :Y|,:6  
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脚本 e0M'\'J  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： v"l8[::  
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如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 T7^?j :kJ/  
余下的脚本计算与屈光度有关的所有参数。 F+]cFx,/  
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分析 A`* l+M^z  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 >uxAti\  
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脚本代码 eVzZfB-=4}  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 3a'#Z
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Dim entity As T_ENTITY mRy0zN>?  
Dim op As T_OPERATION xKkXr-yb`f  
Dim mat As T_MODELMATERIAL F#~*j  
Dim A As Double w3&L 6|,  
Dim pupilDiam As Double FzAzAl5  
Dim eID As Long =&)R2pLs*  
Dim parID As Long kz G W/  
Dim count As Integer x->+wJm@s  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double S4pEBbV^n  
Dim tlens As Double, nlens As Double Cg8  
Dim curv As Double, conic As Double Z^J7r&\V  
Dim ok As Long J$d']%Dwb  
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Sub Main MS]Q\g}U  
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    '用户输入对话框  7gx?LI_e  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 RN$>!b/  
        TextBox 220,21,40,21,.TextBox1 'default: 0 qCB{dp/  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 QQt4pDir>  
        OKButton 40,91,90,21 g""Ep  
        CancelButton 190,91,90,21 iz0:  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 8~F?%!X  
        TextBox 220,49,40,21,.TextBox2 'default: 4 I]%Kd('  
    End Dialog hrGX65>  
    Dim dlg As UserDialog F\jawoO9  
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    ok = Dialog (dlg) czsnPmNEI  
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    If ok=0 Then    'cancel button was pressed ?
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        Print "Execution cancelled." ">5$;{;2r  
        End r[wjE`Z/T  
    End If D^}2ilk!  
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    'Assign accommodation and pupil diameter & use defaults if field left empty j<k-w  
    If dlg.TextBox1 = "" Then DG}s`'  
        A = 0           'Default accommodation biS{.  
    Else Y ` Z,52  
        A = CDbl(dlg.TextBox1) nX\mCO4T  
    End If R:rols"QM  
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    If dlg.TextBox2 = "" Then ;/H/Gn+  
        pupilDiam = 4   'Default pupil diameter  >hzSd@J&  
    Else Y[W:Zhl;  
        pupilDiam = CDbl(dlg.TextBox2) k9;t3-P  
    End If R\<d&+q@  
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    Print " " V9Dq<y-y  
    Print "Accommodation = " & A & " Diopters" "xnULQK  
    Print "Pupil Diameter = " & pupilDiam & " mm" yF1p^>*ak&  
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    ' Calculate new parameters with accommodation TF80WMt  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness xdVsbW)L2  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens h6}rOchj  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens O<ybiPR  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens LB[?kpy  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ~,Yd.?.TI  
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    tlens = 3.767 + 0.04*A                  'Lens thickness ~Orz<%k.  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction itg"dGDk  
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    'Adjust parameters to account for accommodation GB;_!69I  
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    '************************************************************************* i52JY&N  
    'Aqueous thickness (Position of Lens) >UV}^OO  
    '************************************************************************* ZAn9A>5_  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) `sgW0Uf  
    GetCustomElement eID, entity IkG;j+=  
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    parID = FindFullName( "Geometry.Arizona Eye" ) dpX Fx"4A  
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    ' Delete any shift(s) in z <;
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    count = 0 mD|Q+~=|e  
    While GetOperationCount(eID)>count fsWIz1K  
        GetOperation eID, count, op awjAv8tPO!  
        If op.Type="ShiftZ" Then VDxF%!h(  
            DeleteOperation eID,count P]OUzI,  
            count=count-1 gf>GK/^HH  
        End If Qc=-M'9  
        count=count+1 0F.S[!I  
    Wend URt+MTU[  
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    'Set new shift in r'lANl-v  
    op.Type = "ShiftZ" E25w^x2  
    op.val1 = taq /5Vv5d/Z4!  
    op.parent = parID 5:#|Op N  
    AddOperation eID, op (_6JQn  
    Print "Set aqueous humor thickness = " & taq-0.55 W}%"xy]N  
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    '************************************************************************* JT=ax/%Mo  
    'Radius and conic constant of anterior lens l?YO!$  
    '************************************************************************* NciIqF  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) >yVp1Se  
    GetConic eID, entity, curv, conic 2m} bddS  
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    SetConic eID, entity, 1/Rant, CCant ?RW1%+[  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant h%NM%;"H/  
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    '************************************************************************* ReL+V  
    'Radius and conic constant of posterior lens G \Nnw==v  
    '************************************************************************* )heHERbJ  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) qJ<l$Ig  
    GetConic eID, entity, curv, conic n)z:C{  
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    SetConic eID, entity, 1/Rpost, CCpost S
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost /Ahh6=qQY  
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    '************************************************************************* JG7K-W|!c  
    'Lens thickness (Position of posterior lens surface) N R4\TU  
    '************************************************************************* 7$t['2j3  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Oamz>Hplu  
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    ' Delete any z-shift(s) *OIBMx#qxn  
    count = 0 `e?~c'a@  
    While GetOperationCount(eID)>count ^4'!B +}F  
        GetOperation eID, count, op Qw }1mRv  
        If op.Type="ShiftZ" Then y$_]}<b  
            DeleteOperation eID,count 8?x:PkK  
            count=count-1 ?Zk;NL9  
        End If RCxwiZaf33  
        count=count+1 ):}A Quy]  
    Wend e&Q w\Ze  
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    'Set new z-shift m~fDDQs  
    op.Type = "ShiftZ" c@)?V>oe  
    op.val1 = tlens u8`S*i/)m  
    op.parent = parID &-X51O C  
    AddOperation eID, op 065=I+Vo  
    Print "Set lens thickness = " & tlens !(viXV5  
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    '************************************************************************* a2kAZCQ  
    'Lens index of refraction $|TLt{ K  
    '*************************************************************************  Zy8tI#  
    eID = FindMaterial( "Lens" ) uJeJ=7,EO  
    GetModelMaterial eID, mat zjSl;ru  
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    mat.Nd = nlens T:9M|mD  
    SetModelMaterial eID, mat [TFp2B~)#  
    Print "Set lens index of refraction = " & nlens vts"  
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    '************************************************************************* m/(/!MVy  
    'Pupil diameter hY!>>  
    '************************************************************************* W:6#0b"_#  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) %+;l|Z{Uf  
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    'Adjust pupil diameter (trimming volume inner hole) 4FZ/~Y1}  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ! hEZV&y  
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    ' Adjust pupil location to just in front of the lens [McqwU/Q  
    parID = FindFullName( "Geometry.Arizona Eye" ) 5p5"3m;M7  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ,dw\y/d
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    count = 0 >!{8)ti  
    While GetOperationCount(eID)>count Ggsts  
        GetOperation eID, count, op bAuiMw7!  
        If op.Type="ShiftZ" Then 8Gy*BpmJn  
            DeleteOperation eID,count }d iE'  
            count=count-1 0Zo><=  
        End If 'zT7$ .L  
        count=count+1 N'$P( bx  
    Wend ^Jdg%U?  
    op.Type = "ShiftZ" \u(Gj]B#"  
    op.val1 = taq-0.01 oIIi_yc  
    op.parent = parID yf`_?gJ6d  
    AddOperation eID, op ) LTV+?  
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    Print "Set pupil diameter = " & pupilDiam PYY<
  
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    'Update AZ Eye subassembly Description Fm6]mz%~u#  
    eID = FindFullName( "Geometry.Arizona Eye" ) 9F6dKPN:  
    GetEntity eID, entity -f1}N|hy  
    entity.Description = "Accommodation = " & A & "D" ImH9 F\  
    SetEntity eID, entity QtWe,+WWV  
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    Update '&K' 0qG  
    Print "DONE!" ,!g/1m  
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End Sub !8W0XUqh+  
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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： W[]|Uu/%  
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Accommodation = 4 Diopters >1]hR)Ip  
Pupil Diameter = 4 mm OT6Te&  
Set aqueous humor thickness = 2.81 _FS #~z'j  
Set anterior lens radius = 10.4 and conic constant = -2.375869 DRXUQH  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 >uQjygjj  
Set lens thickness = 3.927 Pc5C*{C  
Set lens index of refraction = 1.42672 KbK!4  
Set pupil diameter = 4 U~@;2\ o  
DONE! In!^+j  
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