[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 "<Q,|
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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。 H[e=^JuD  
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模型 voitdz  
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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。 1Y6DzWI  
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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. -"}mmTa*<  
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光源 J9V,U;"\  
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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。 ~6!TMVr  
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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。 g54b}vzm  
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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。 ^)%TQ.  
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视网膜的散射 i!7|YAu  
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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。 "b `R_gG9  
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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。 T*bBw  
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脚本 NA-)7i*>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： @";zM&  
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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。 _gn`Y(c$%  
余下的脚本计算与屈光度有关的所有参数。 N^@aO&+A  
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分析 P;DGs]PF  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 @@~Ql  
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脚本代码 0hoi=W6AQ  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. ])D39  
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Dim entity As T_ENTITY v
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Dim op As T_OPERATION m0[JiwPI  
Dim mat As T_MODELMATERIAL d"~-D;  
Dim A As Double ;Q8LA",5d  
Dim pupilDiam As Double *-lw2M9V  
Dim eID As Long :}{,u6\  
Dim parID As Long uYy&<_r  
Dim count As Integer @/ G$ C9<  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double us$=)m~v+  
Dim tlens As Double, nlens As Double (sN;B)  
Dim curv As Double, conic As Double {wy#HYhv  
Dim ok As Long 8D5v'[j-  
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Sub Main rFl6xM;F  
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    '用户输入对话框 'A)r)z{X  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 D
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        TextBox 220,21,40,21,.TextBox1 'default: 0 /+g)J0
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        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 KX
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        OKButton 40,91,90,21 >xK!J?!K  
        CancelButton 190,91,90,21 SM1[)jZ-  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 +L
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        TextBox 220,49,40,21,.TextBox2 'default: 4 h&O8e;S#  
    End Dialog gkRbb   
    Dim dlg As UserDialog "79"SSfOc  
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    ok = Dialog (dlg) } Rs@  
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    If ok=0 Then    'cancel button was pressed hsEQ6  
        Print "Execution cancelled." ,'z=cB`+o  
        End HI%#S&d  
    End If c$AwJhl^]  
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    'Assign accommodation and pupil diameter & use defaults if field left empty Kh,zp{  
    If dlg.TextBox1 = "" Then +#=l{_Z,ZJ  
        A = 0           'Default accommodation dRu|*s  
    Else [
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        A = CDbl(dlg.TextBox1) >cYYr@S  
    End If <WCTJ!Z  
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    If dlg.TextBox2 = "" Then k<i#agq  
        pupilDiam = 4   'Default pupil diameter H(,D5y`k1  
    Else ne-;gTP;  
        pupilDiam = CDbl(dlg.TextBox2) Vb$
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    End If `%
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    Print " " OS7^S1r-  
    Print "Accommodation = " & A & " Diopters" hUO&rov3@  
    Print "Pupil Diameter = " & pupilDiam & " mm" @24)*d^1  
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    ' Calculate new parameters with accommodation \2huDNW& !  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 3wf&,4`EX  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens |z%:{  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ?D8+wj  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens zc#$hIi  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens " _{o}
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    tlens = 3.767 + 0.04*A                  'Lens thickness N_^s;Qj  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction %{*)-_M  
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    'Adjust parameters to account for accommodation 5?M d  
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    '************************************************************************* U2TR>0l  
    'Aqueous thickness (Position of Lens) H\!p%Y  
    '************************************************************************* M*n@djL$\~  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) k/]4L!/ T  
    GetCustomElement eID, entity  SG@-b(  
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    parID = FindFullName( "Geometry.Arizona Eye" ) :y%CP8  
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    ' Delete any shift(s) in z mNDz|Ln  
    count = 0 }{#ty uzAo  
    While GetOperationCount(eID)>count K#_x.:<J  
        GetOperation eID, count, op PbpnjvVrM  
        If op.Type="ShiftZ" Then GX-V|hLaGX  
            DeleteOperation eID,count Z?"f#  
            count=count-1 (eEs0  
        End If W3aFao>!OZ  
        count=count+1 /.m&rS  
    Wend U?.cbB,  
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    'Set new shift in 1 |T{RY5  
    op.Type = "ShiftZ" !${7)=|=1  
    op.val1 = taq 14Y<-OO: k  
    op.parent = parID & cV$`L  
    AddOperation eID, op M|DVFC  
    Print "Set aqueous humor thickness = " & taq-0.55 +$y%H  
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    '************************************************************************* qGVf!R  
    'Radius and conic constant of anterior lens %!X9>i>  
    '************************************************************************* X" m0||  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 97 eEqI$#  
    GetConic eID, entity, curv, conic 0tb%h[%,M  
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    SetConic eID, entity, 1/Rant, CCant h}$g}f%$+  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant INjr$'*  
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    '************************************************************************* -'%>Fon  
    'Radius and conic constant of posterior lens Ql8s7%  
    '************************************************************************* kVeR{i<*(  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) R!Lh~~@{(  
    GetConic eID, entity, curv, conic '
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    SetConic eID, entity, 1/Rpost, CCpost G~mLc  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ($or@lfs  
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    '************************************************************************* ;eY.4/*R  
    'Lens thickness (Position of posterior lens surface) K6d2}!5  
    '************************************************************************* W{W8\  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) z&KrG  
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    ' Delete any z-shift(s) UI%Z`.&  
    count = 0 Qo$j'|lD  
    While GetOperationCount(eID)>count Mv?$zV"`#  
        GetOperation eID, count, op ic;M=dsh:  
        If op.Type="ShiftZ" Then Cno+rmsfT  
            DeleteOperation eID,count #
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            count=count-1 1"yr`,}?8r  
        End If }5]2tH${  
        count=count+1 &,8F!)[9  
    Wend z)Gd3C  
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    'Set new z-shift slTE.  
    op.Type = "ShiftZ" e%_J O7  
    op.val1 = tlens C116c"  
    op.parent = parID SUC'o"  
    AddOperation eID, op F?+\J =LT  
    Print "Set lens thickness = " & tlens mJNw<T4!/  
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    '************************************************************************* E! GH$%:;  
    'Lens index of refraction ;V0^uB.z  
    '************************************************************************* cw"Ou%  
    eID = FindMaterial( "Lens" ) L+.&e4f'oj  
    GetModelMaterial eID, mat >r\q6f#J4  
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    mat.Nd = nlens Bw/8-:eb  
    SetModelMaterial eID, mat 1Eh6ti  
    Print "Set lens index of refraction = " & nlens (Cb;=:3G  
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    '************************************************************************* H@!]5 <:9  
    'Pupil diameter lc[)O3,,B  
    '************************************************************************* 363KU@`  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) _J"fgxW  
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    'Adjust pupil diameter (trimming volume inner hole) iY*fp=c9  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" $W]}m"l  
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    ' Adjust pupil location to just in front of the lens RJ1@a  
    parID = FindFullName( "Geometry.Arizona Eye" ) Dv"HFQuF  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) s[bQO1g;*  
    count = 0 J'C9}7G  
    While GetOperationCount(eID)>count = glF6a  
        GetOperation eID, count, op b/"gUYo  
        If op.Type="ShiftZ" Then i_(6}Y&  
            DeleteOperation eID,count ShesJj  
            count=count-1 c!ieN9^+  
        End If fSVb.MZa7  
        count=count+1 ,@kLH"a0  
    Wend $p|Im,  
    op.Type = "ShiftZ" s}F.D^^G  
    op.val1 = taq-0.01 m6uFmU*<M}  
    op.parent = parID k8c(|/7d  
    AddOperation eID, op #y-R*4G  
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    Print "Set pupil diameter = " & pupilDiam GTM@9^  
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    'Update AZ Eye subassembly Description h S)lQl:^  
    eID = FindFullName( "Geometry.Arizona Eye" ) z HT#bP:o  
    GetEntity eID, entity &=]!8z=  
    entity.Description = "Accommodation = " & A & "D" lVCnu>8  
    SetEntity eID, entity ,bzC|AK  
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    Update jO-T1P']Y  
    Print "DONE!" ~BiLzT1,  
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End Sub ,BFw-A  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： RzU
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Accommodation = 4 Diopters tA]u=-_h  
Pupil Diameter = 4 mm .'>d7  
Set aqueous humor thickness = 2.81 cJf&R^[T  
Set anterior lens radius = 10.4 and conic constant = -2.375869 h=Q2 ?O8  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 n&,X']z.  
Set lens thickness = 3.927 P?^%i  
Set lens index of refraction = 1.42672 osc A\r  
Set pupil diameter = 4 pk`5RDBu  
DONE! X.sOZb?$  
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