[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 vB'>[jvA|  
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。 /F)H\*  
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模型 JRaq!/[(  
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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。 ino:N5&;;  
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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. .a'f|c6  
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光源 (Z]HX@"{J  
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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。 <
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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。 baV>N[F&  
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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。 KngTc(^_D  
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视网膜的散射 r!1D*v5&:  
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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。 : 18KR*;p  
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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。 Rhc-q
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脚本 OJ
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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： yZr M.%V  
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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。 !G^L/?z3  
余下的脚本计算与屈光度有关的所有参数。 wI]"U2L5  
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分析 ^bg2[FV  
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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。 -}O1dEn.  
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脚本代码 0sN.H=   
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. CYYkzcc^  
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Dim entity As T_ENTITY X[`bMa7IB(  
Dim op As T_OPERATION ];'v8
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Dim mat As T_MODELMATERIAL \PDd$syDA  
Dim A As Double L pR''`2BT  
Dim pupilDiam As Double  ]#7zk9  
Dim eID As Long w
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Dim parID As Long \drqG&wl  
Dim count As Integer VE+IKj!VG0  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 7K)6^r^  
Dim tlens As Double, nlens As Double FZ!`B]]le,  
Dim curv As Double, conic As Double /VmR<C?
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Dim ok As Long 3)-/
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Sub Main ;};wq&b#  
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    '用户输入对话框 }|P
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    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 }*.0N;;C  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ^Wxad?@  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 -@T/b$]'n  
        OKButton 40,91,90,21 PV|uPuz  
        CancelButton 190,91,90,21 64hk2a8  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 mM`wITy  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ]-ZEWt6lsc  
    End Dialog 311LC cRp  
    Dim dlg As UserDialog aLIBD'z  
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    ok = Dialog (dlg) 626Z5Afg  
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    If ok=0 Then    'cancel button was pressed 8_T6_jL<  
        Print "Execution cancelled." {?'fyEeg  
        End 7S?4XyU/o  
    End If A&nU]R8S  
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    'Assign accommodation and pupil diameter & use defaults if field left empty @V03a )6,h  
    If dlg.TextBox1 = "" Then J_s>N  
        A = 0           'Default accommodation v\p;SwI  
    Else e{m2l2Tx:  
        A = CDbl(dlg.TextBox1) v
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    End If @)Ofi j  
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    If dlg.TextBox2 = "" Then @}u9Rn*d;  
        pupilDiam = 4   'Default pupil diameter **}h&k&%2  
    Else `FoxP  
        pupilDiam = CDbl(dlg.TextBox2) H^YSJ6  
    End If *Z|y'<s  
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    Print " " :=J,z,H_U  
    Print "Accommodation = " & A & " Diopters" "~D]E7Q3y  
    Print "Pupil Diameter = " & pupilDiam & " mm" l
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    ' Calculate new parameters with accommodation K_dOq68_  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness O%FPS=  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens _-EyT  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens L'u\w  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens fFc/ d(  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens [7[0^ad  
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    tlens = 3.767 + 0.04*A                  'Lens thickness k1QpKn*  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction *8LMn  
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    'Adjust parameters to account for accommodation daYx76yP_?  
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    '************************************************************************* 3+XOZh8  
    'Aqueous thickness (Position of Lens) ra o[VZ  
    '************************************************************************* ayiu,DXx  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) rb|U;)C  
    GetCustomElement eID, entity zzxGAVu  
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    parID = FindFullName( "Geometry.Arizona Eye" ) kXf'5p1  
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    ' Delete any shift(s) in z gSh+}r<7  
    count = 0 ~c&bH]cj  
    While GetOperationCount(eID)>count cJrmm2.0kD  
        GetOperation eID, count, op vvm0t"|\  
        If op.Type="ShiftZ" Then yxH ( c  
            DeleteOperation eID,count Sv +IS  
            count=count-1 vMS |$L  
        End If <WcR,d  
        count=count+1 2o'Wy  
    Wend }5hqDBK?  
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    'Set new shift in IP(Vr7-v  
    op.Type = "ShiftZ" l?Ya"C`FL  
    op.val1 = taq cZ|\.0-  
    op.parent = parID a]MX)?  
    AddOperation eID, op :3I@(k\PY  
    Print "Set aqueous humor thickness = " & taq-0.55 Y*14v~\'  
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    '************************************************************************* kOed ]>H  
    'Radius and conic constant of anterior lens *FMMjz  
    '************************************************************************* }b-g*dn]5  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) (_"*NY0  
    GetConic eID, entity, curv, conic og kD^   
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    SetConic eID, entity, 1/Rant, CCant >M`CV
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    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant *"{lMZ+  
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    '************************************************************************* #H:7@  
    'Radius and conic constant of posterior lens F~P%AjAx'  
    '************************************************************************* *cgI.+  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) lqm1!5dt  
    GetConic eID, entity, curv, conic 1A\OC  
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    SetConic eID, entity, 1/Rpost, CCpost sPR1?:0:  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost sn)3ZA  
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    '************************************************************************* Zd')57{  
    'Lens thickness (Position of posterior lens surface) 0`[wpZ  
    '************************************************************************* zlEX+=3  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) nuw70*ell  
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    ' Delete any z-shift(s) }3OKC2K~  
    count = 0 Ym =FgM\  
    While GetOperationCount(eID)>count 
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        GetOperation eID, count, op E/%9jDTQ  
        If op.Type="ShiftZ" Then * iF]n2g:  
            DeleteOperation eID,count |v$JCU3!A  
            count=count-1 RH&~+5  
        End If MpF$xzh  
        count=count+1 )3>hhuaa  
    Wend K5x
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    'Set new z-shift ce7CcHQ?B  
    op.Type = "ShiftZ" E(Z8  
    op.val1 = tlens %@6}GmK^  
    op.parent = parID 1q,{0s_kp  
    AddOperation eID, op  [D<1CF  
    Print "Set lens thickness = " & tlens R wZ]),o  
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    '************************************************************************* {o.FlX  
    'Lens index of refraction u
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    '************************************************************************* 5) pj]S!]-  
    eID = FindMaterial( "Lens" )  O4og?h>  
    GetModelMaterial eID, mat Vz=PiMO  
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    mat.Nd = nlens XBp?w  
    SetModelMaterial eID, mat ]%IT|/;9Y  
    Print "Set lens index of refraction = " & nlens 9f<MQ6_UU  
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    '************************************************************************* sXD1C2o  
    'Pupil diameter V;,{}  
    '************************************************************************* ~wkj&yVT  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Y7*U:I+N  
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    'Adjust pupil diameter (trimming volume inner hole) i?
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" c'S,hCe*  
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    ' Adjust pupil location to just in front of the lens *%S"eWb  
    parID = FindFullName( "Geometry.Arizona Eye" ) p(/dBt[3k  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) /#m=*&!CB  
    count = 0 VB,?Mo}R  
    While GetOperationCount(eID)>count `s8{C b=}1  
        GetOperation eID, count, op N<IT w/@^  
        If op.Type="ShiftZ" Then Yd#/1!A7u  
            DeleteOperation eID,count =9fajRFTt  
            count=count-1 JNJ=e,O,  
        End If k[:bQ)H  
        count=count+1 6{^E{go  
    Wend *fn*h[pV&  
    op.Type = "ShiftZ" 9*{[buZX  
    op.val1 = taq-0.01 9mmCp&~Z  
    op.parent = parID X ><?F|#7T  
    AddOperation eID, op rjp-Fw~1w  
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    Print "Set pupil diameter = " & pupilDiam `CgaS#  
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    'Update AZ Eye subassembly Description :[hgxJu+  
    eID = FindFullName( "Geometry.Arizona Eye" ) {6_|/KE9_  
    GetEntity eID, entity NqDHCI  
    entity.Description = "Accommodation = " & A & "D" ?C&z]f3(:  
    SetEntity eID, entity oaoU _V  
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    Update w[IE
 
    Print "DONE!" S&b*rA02zp  
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End Sub zhpt%7So  
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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： CkdP#}f  
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Accommodation = 4 Diopters ,z-}t& _t  
Pupil Diameter = 4 mm zY"1drE>G  
Set aqueous humor thickness = 2.81 xK6n0] A  
Set anterior lens radius = 10.4 and conic constant = -2.375869 :F{:Z*Fi0  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 .2v_H5<  
Set lens thickness = 3.927 5`gQ~  
Set lens index of refraction = 1.42672 .xH5fMj,"  
Set pupil diameter = 4 /q5v"iX]T  
DONE! RkBb$q9F]  
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