[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 =r1@?x  
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。 n0<I  
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模型 ^E`SR6_cmj  
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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。 D+xHTQNTL  
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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. kqyPb$Wy  
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光源 B0#JX MX9  
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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。 FCMV1,  
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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。 G
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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##7^  
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视网膜的散射 }*s%|!{H  
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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。 N5\]VCX  
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脚本 Nn]|#lLP  
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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： 0k\BE\PQk  
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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。 3}lT"K  
余下的脚本计算与屈光度有关的所有参数。 c.;}e:)s  
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分析 _bm8m
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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。 Y3RaR 9  
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脚本代码 ltH?Ew<
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. "ke>O'   
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Dim entity As T_ENTITY [@LA<Z_
 
Dim op As T_OPERATION ;#jE??E/:  
Dim mat As T_MODELMATERIAL ndCHWhi  
Dim A As Double ?f\ ~:Gm/  
Dim pupilDiam As Double 6Yu&'[?H$  
Dim eID As Long { *&Wc Os  
Dim parID As Long _)U[c;^6  
Dim count As Integer 'l7ey3B%  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double B{ptP4As-  
Dim tlens As Double, nlens As Double V+'C71-P  
Dim curv As Double, conic As Double $
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Dim ok As Long /+g9C(['  
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Sub Main Z\9DtvV
 
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    '用户输入对话框 v3q.,I_  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 `1fNB1c  
        TextBox 220,21,40,21,.TextBox1 'default: 0 vl,Ff9  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 nB .?=eUa  
        OKButton 40,91,90,21 ,VdNP  
        CancelButton 190,91,90,21 JsZLBq*lP  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 b|'{f?  
        TextBox 220,49,40,21,.TextBox2 'default: 4 9yrSCDu00  
    End Dialog gf\F%VmSN  
    Dim dlg As UserDialog kl0|
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    ok = Dialog (dlg) @3_[NI%  
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    If ok=0 Then    'cancel button was pressed io1hUZ  
        Print "Execution cancelled." #i1z&b#@  
        End zZ*\v  
    End If X]T&kdQ6q  
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    'Assign accommodation and pupil diameter & use defaults if field left empty r]<?,xx[  
    If dlg.TextBox1 = "" Then dPmtU{E<M  
        A = 0           'Default accommodation 2C59f
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    Else !x@3U^${  
        A = CDbl(dlg.TextBox1) L$ki>._i\  
    End If =)Z~w`  
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    If dlg.TextBox2 = "" Then pX LXkF?  
        pupilDiam = 4   'Default pupil diameter |[B JZ  
    Else snm1EPj  
        pupilDiam = CDbl(dlg.TextBox2) #P)(/>nF  
    End If RAUD8Z  
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    Print " " D]StDOmM  
    Print "Accommodation = " & A & " Diopters" VTIRkC wl@  
    Print "Pupil Diameter = " & pupilDiam & " mm" :5, k64'D  
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    ' Calculate new parameters with accommodation
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    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness z1vSt[s  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens EWNm }C9  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens WTX!)H6Zv  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens *:tfz*FG$G  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens z\zqmW6  
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    tlens = 3.767 + 0.04*A                  'Lens thickness \{K~x@`  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction oa q!<lI  
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    'Adjust parameters to account for accommodation l1uv]t <  
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    '************************************************************************* dR@XwEpP  
    'Aqueous thickness (Position of Lens) ';iLk[  
    '************************************************************************* Jnl#d0) -  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) <R.Ipyt.  
    GetCustomElement eID, entity FwaYp\z  
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    parID = FindFullName( "Geometry.Arizona Eye" ) <S@XK%  
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    ' Delete any shift(s) in z 5ji#rIAhxh  
    count = 0 {O"N2W  
    While GetOperationCount(eID)>count Y'eE({)<K  
        GetOperation eID, count, op =}wqo6Bn|  
        If op.Type="ShiftZ" Then PGNH<E)  
            DeleteOperation eID,count w3E#v&"=Y  
            count=count-1 ]G
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        End If rcU*6`IWA  
        count=count+1 wG}Rh,  
    Wend _sX@BE  
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    'Set new shift in Kk|4  
    op.Type = "ShiftZ" >#EOCo  
    op.val1 = taq 1%Su~Z"W>  
    op.parent = parID m>&
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    AddOperation eID, op R!y`p:O C  
    Print "Set aqueous humor thickness = " & taq-0.55 ,f)#&}x*2+  
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    '************************************************************************* kDWMget$  
    'Radius and conic constant of anterior lens RElIWqgY  
    '************************************************************************* =PAsyj  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) *9)yN[w  
    GetConic eID, entity, curv, conic 07#e{   
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    SetConic eID, entity, 1/Rant, CCant :V ZXI#([  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant y\@INA^  
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    '************************************************************************* H%G|8,4  
    'Radius and conic constant of posterior lens Dg'BlrwbR  
    '************************************************************************* 0$:jZ/._  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 45U!\mG  
    GetConic eID, entity, curv, conic t~kh?u
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    SetConic eID, entity, 1/Rpost, CCpost ~d"9?K^#  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost +Vw]DLWR  
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    '************************************************************************* .)[0yW&  
    'Lens thickness (Position of posterior lens surface) 2kW*Z7@D  
    '************************************************************************* D V=xqC6}  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) ,ocAB;K  
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    ' Delete any z-shift(s) DTo P|P  
    count = 0 (Q[(]dfc  
    While GetOperationCount(eID)>count vNSeNS@jxC  
        GetOperation eID, count, op D]NJ^.X  
        If op.Type="ShiftZ" Then Ux+UcBKm-  
            DeleteOperation eID,count B'8T+qvA  
            count=count-1 v&r\Z @%  
        End If 2f0qfF  
        count=count+1  ?~=5x  
    Wend <gu>06  
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    'Set new z-shift ZIs=%6""&  
    op.Type = "ShiftZ" ?cKe~Q?3  
    op.val1 = tlens ,ePl>m:Z  
    op.parent = parID P&5kO;ia  
    AddOperation eID, op EPd
 
    Print "Set lens thickness = " & tlens NT;cT
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    '************************************************************************* vu|-}v?:  
    'Lens index of refraction xFp?+a  
    '************************************************************************* W,bu=2K6  
    eID = FindMaterial( "Lens" ) TxvvCV^  
    GetModelMaterial eID, mat @r3,|tkrz  
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    mat.Nd = nlens tf4clzSTa  
    SetModelMaterial eID, mat $8WeWmY  
    Print "Set lens index of refraction = " & nlens M@<r8M]G  
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    '************************************************************************* \W+Hzf] W#  
    'Pupil diameter G0b##-.'^  
    '************************************************************************* k~IRds@G  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 3='
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    'Adjust pupil diameter (trimming volume inner hole) EFzPt?l  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" gP
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    ' Adjust pupil location to just in front of the lens mu$rG3M  
    parID = FindFullName( "Geometry.Arizona Eye" ) ~*hCTqHvN  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) i#:M2&twE  
    count = 0 Ls
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    While GetOperationCount(eID)>count 0`$fs.4c  
        GetOperation eID, count, op H?wf%0  
        If op.Type="ShiftZ" Then >9,:i)m_  
            DeleteOperation eID,count BDT"wy8  
            count=count-1 DA^!aJ6iF  
        End If Iwe  
        count=count+1 Ib2n Bg>j  
    Wend oq[r+E-]$@  
    op.Type = "ShiftZ" j026CVL  
    op.val1 = taq-0.01 (N?nOOQ  
    op.parent = parID 79Ur1-]/  
    AddOperation eID, op [7h/ 2La#  
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    Print "Set pupil diameter = " & pupilDiam ', P_a,\  
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    'Update AZ Eye subassembly Description ?$.x%G+  
    eID = FindFullName( "Geometry.Arizona Eye" ) qflOi8  
    GetEntity eID, entity ]e(\<R6Gf  
    entity.Description = "Accommodation = " & A & "D" <['ucp  
    SetEntity eID, entity eqk.+~^  
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    Update 2[i(XG{/  
    Print "DONE!" : $N43_
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End Sub 5V8`-yO9  
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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： z-^/<u1p  
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Accommodation = 4 Diopters vDC
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Pupil Diameter = 4 mm  Y}e3:\  
Set aqueous humor thickness = 2.81 CPcB17!  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ]sJjV A  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 BFZ\\rN`  
Set lens thickness = 3.927 {m/KD 'b_  
Set lens index of refraction = 1.42672 N5mhs#  
Set pupil diameter = 4 5?*Iaw  
DONE! >%A~ :  
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