[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 -d8TD*^  
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。 WxW7qt  
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模型 4Yxo~ m(  
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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。 eKgisY4#  
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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. e.]KL('  
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光源 ,pqGX3  
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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。 =fu :@+  
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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。 z)'Mk[  
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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。 dArDP[w  
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视网膜的散射 ="x\`+U  
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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。 &F\?  
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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。 S?RN?1  
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脚本 [E+$?a=  
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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： =g/{%;  
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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。 ,z3{u162  
余下的脚本计算与屈光度有关的所有参数。 0|2%vh>J  
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分析 CF+_/s#j^  
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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-bJS6  
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脚本代码 8aO~/i:(.  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. 1&^MfP}  
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Dim entity As T_ENTITY 1"/He ` 4  
Dim op As T_OPERATION \cC%!4  
Dim mat As T_MODELMATERIAL ,oaw0Vw  
Dim A As Double G"X8}:}  
Dim pupilDiam As Double la( <8  
Dim eID As Long =Vy`J)z9  
Dim parID As Long _/Gczy4)#  
Dim count As Integer f@8>HCI  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double b8LoIY*  
Dim tlens As Double, nlens As Double 5O~HWBX.  
Dim curv As Double, conic As Double 0@G")L Ue0  
Dim ok As Long S|apw7C  
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Sub Main ^
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    '用户输入对话框 SG
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    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 c7tfRq n+  
        TextBox 220,21,40,21,.TextBox1 'default: 0 vz^<YZMu  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 vFE;D@bz:  
        OKButton 40,91,90,21 ?_"+^R z  
        CancelButton 190,91,90,21 bx]N>k J  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 Q-MQ9'  
        TextBox 220,49,40,21,.TextBox2 'default: 4 2P/K K  
    End Dialog f 1w~!O9  
    Dim dlg As UserDialog 2>
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    ok = Dialog (dlg) 66.5QD0  
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    If ok=0 Then    'cancel button was pressed 9AxCiT.  
        Print "Execution cancelled." U+)xu>I  
        End ZKQG:M~|  
    End If R zf  
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    'Assign accommodation and pupil diameter & use defaults if field left empty ?T>'j mmV=  
    If dlg.TextBox1 = "" Then q4}PM[K?=\  
        A = 0           'Default accommodation slg ]#Dy  
    Else S+'rG+NJ  
        A = CDbl(dlg.TextBox1) +n<k)E@>J  
    End If NZ/yBOD(  
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    If dlg.TextBox2 = "" Then DyeQJ7p  
        pupilDiam = 4   'Default pupil diameter N@Y ljz|  
    Else vC1v"L;[o/  
        pupilDiam = CDbl(dlg.TextBox2) UB 6mqjPK  
    End If fv`O4  
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    Print " " 6oLwfTy  
    Print "Accommodation = " & A & " Diopters" ,WvY$_#xW%  
    Print "Pupil Diameter = " & pupilDiam & " mm" :um|nRwy9  
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    ' Calculate new parameters with accommodation .&9 i  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness PH> b-n  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens %{/%mJoX  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 3t<a $i
 
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens O~59FuL  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ]da^xWK  
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    tlens = 3.767 + 0.04*A                  'Lens thickness  ?p(/_@  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction QHWBAGA  
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    'Adjust parameters to account for accommodation p=C%Hmd5E  
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    '************************************************************************* 6I!7c^]t  
    'Aqueous thickness (Position of Lens) mwY IJy[  
    '************************************************************************* $&<uT  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ;zYqsS  
    GetCustomElement eID, entity :^Fh!br==  
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    parID = FindFullName( "Geometry.Arizona Eye" ) BCe|is0  
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    ' Delete any shift(s) in z `;l?12|X  
    count = 0 ^Ve<>b  
    While GetOperationCount(eID)>count t=u Qb=  
        GetOperation eID, count, op {X*^s5{
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        If op.Type="ShiftZ" Then Gg~QAsks   
            DeleteOperation eID,count #7ov#_2Jd  
            count=count-1 >IX/< {);M  
        End If 549jWG  
        count=count+1 +=]!P#  
    Wend ZVbl88,(l  
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    'Set new shift in _>=L>*  
    op.Type = "ShiftZ" !<UJ6t}  
    op.val1 = taq hFk3[zTy  
    op.parent = parID ~}!3G  
    AddOperation eID, op +8v9flh  
    Print "Set aqueous humor thickness = " & taq-0.55 2-"0 ^n{  
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    '************************************************************************* O/.Uh`T`6  
    'Radius and conic constant of anterior lens rz"txN  
    '************************************************************************* xGU(n_Y  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) { .*y  
    GetConic eID, entity, curv, conic kKPi:G52F  
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    SetConic eID, entity, 1/Rant, CCant % ,N<  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant f>s?4  
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    '************************************************************************* = pI?A^  
    'Radius and conic constant of posterior lens 2P]L9'N{Y  
    '************************************************************************* Wm H~m k"  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) _{Sm k[  
    GetConic eID, entity, curv, conic / }Rz=&  
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    SetConic eID, entity, 1/Rpost, CCpost $5v0m#[^  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ]c&<zeX,  
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    '************************************************************************* u7xDau(c  
    'Lens thickness (Position of posterior lens surface) <BSc* 9Q  
    '************************************************************************* "+zCS|   
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) w=|GJ0  
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    ' Delete any z-shift(s) DAwqo.m  
    count = 0 s;1]tD  
    While GetOperationCount(eID)>count |A%<Z(  
        GetOperation eID, count, op }gkM^*$:%  
        If op.Type="ShiftZ" Then \`, [)`  
            DeleteOperation eID,count vsL[*OeI  
            count=count-1 tX!nsm1  
        End If EwS!]h?  
        count=count+1 i5>+}$1  
    Wend +525{Tj  
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    'Set new z-shift .XkMk|t8  
    op.Type = "ShiftZ" % aUsOB-RV  
    op.val1 = tlens k<RZKwQc  
    op.parent = parID 0 a~HiIh  
    AddOperation eID, op 66#
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    Print "Set lens thickness = " & tlens \m=?xb8 f  
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    '************************************************************************* vA)O{W\o  
    'Lens index of refraction P/JK$nb  
    '************************************************************************* 341?0%=  
    eID = FindMaterial( "Lens" ) 84i_k  
    GetModelMaterial eID, mat v`V7OD#:j]  
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    mat.Nd = nlens oo=#XZkk  
    SetModelMaterial eID, mat QRLJ_W^&u  
    Print "Set lens index of refraction = " & nlens x f4{r+  
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    '************************************************************************* YUQtMf9  
    'Pupil diameter 7O`o ovW$  
    '************************************************************************* - }!H3]tr  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) q!f1~aG  
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    'Adjust pupil diameter (trimming volume inner hole) ri1C-TJM)  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" o$C|J]%  
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    ' Adjust pupil location to just in front of the lens 9_fePS|Z4  
    parID = FindFullName( "Geometry.Arizona Eye" ) _MWM;f`b  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) |wox1Wt|E  
    count = 0 D;Gq)]O  
    While GetOperationCount(eID)>count +%N KQ'49I  
        GetOperation eID, count, op Pv<FLo%u<  
        If op.Type="ShiftZ" Then iqhOi|!  
            DeleteOperation eID,count *2}O-e  
            count=count-1 M[~{Vd  
        End If `]$?uQ  
        count=count+1 yMLOUUWa8x  
    Wend kCUT ^  
    op.Type = "ShiftZ" 19(Dj&x  
    op.val1 = taq-0.01 u@p?  
    op.parent = parID hNXBVIL<&  
    AddOperation eID, op e75UMWaeC  
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    Print "Set pupil diameter = " & pupilDiam PN$ .X"D8  
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    'Update AZ Eye subassembly Description qQ7w&9r.M  
    eID = FindFullName( "Geometry.Arizona Eye" ) j%<}jw[2  
    GetEntity eID, entity 4R>zPEo  
    entity.Description = "Accommodation = " & A & "D" Je4Z(kj 0  
    SetEntity eID, entity xx*2?i  
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    Update _SZ5P>GIU  
    Print "DONE!" ]WJfgN4  
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End Sub jnuY{0(&  
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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： 6Ggs JU  
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Accommodation = 4 Diopters [O-sVYB  
Pupil Diameter = 4 mm /T0nLp`gi  
Set aqueous humor thickness = 2.81 {+("C] b  
Set anterior lens radius = 10.4 and conic constant = -2.375869 >+cVs:  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 lf>nbv
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Set lens thickness = 3.927 (I{ $kB"p  
Set lens index of refraction = 1.42672 %up}p/?  
Set pupil diameter = 4 1'6cGpZY  
DONE! rFJ[dz  
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