[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 O<f_-n@G|  
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。 ci
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模型 hr@KWE`  
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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。 -N5r[*>  
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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. bm%2K@ /U  
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光源 (5-"5<-@R  
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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。 *v:+AE  
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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。 Ca+d ?IS  
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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。 VbBZ\`b  
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视网膜的散射 N Ja]UZx  
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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。 "TtK!>!.  
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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。 yKZ~ ^  
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脚本 Vl^jTX5N  
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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： %PlPXoG=  
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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。 e yTYg  
余下的脚本计算与屈光度有关的所有参数。 XFK$p^qu  
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分析 Dvd.Q/f  
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屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 lt,x(2  
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脚本代码 _?q\tyf3  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. %*}JDx#@  
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Dim entity As T_ENTITY Zpu>T2Tp  
Dim op As T_OPERATION VJ_E]}H  
Dim mat As T_MODELMATERIAL Qt>yRt  
Dim A As Double puXJ:yo(  
Dim pupilDiam As Double 2vj)3%:7#E  
Dim eID As Long 8{?Oi'-|0  
Dim parID As Long %HYC-TF#  
Dim count As Integer 8(Z*Vz uu  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double P7u5Ykc*  
Dim tlens As Double, nlens As Double hC6$>tl  
Dim curv As Double, conic As Double L
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Dim ok As Long +hXph  
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Sub Main #+Vvf
  
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    '用户输入对话框 /-BplU*"9  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 |&RdOjw$u  
        TextBox 220,21,40,21,.TextBox1 'default: 0 {Qw,L;R  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 (x.K%QC)  
        OKButton 40,91,90,21 NO* 1km[#  
        CancelButton 190,91,90,21 Lk3@Eu)  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 /}M@ @W  
        TextBox 220,49,40,21,.TextBox2 'default: 4 P?TFX.p7
 
    End Dialog sF|<m)Kt{W  
    Dim dlg As UserDialog Iupk
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    ok = Dialog (dlg) .`)IC
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    If ok=0 Then    'cancel button was pressed <7TpC@"/g  
        Print "Execution cancelled." M5%u>$2  
        End :_Ng`b/  
    End If {Ja#pt  
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    'Assign accommodation and pupil diameter & use defaults if field left empty p(Qm\g<  
    If dlg.TextBox1 = "" Then )*s.AFu]7x  
        A = 0           'Default accommodation @.CPZT  
    Else 37lmB '~  
        A = CDbl(dlg.TextBox1) u[d8)+VX  
    End If C'5i>;  
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    If dlg.TextBox2 = "" Then Ah)7A|0rT  
        pupilDiam = 4   'Default pupil diameter {SROg;vA  
    Else i 3?zYaT  
        pupilDiam = CDbl(dlg.TextBox2) 0Y!Bb2m  
    End If <[a9"G7  
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    Print " " urog.Q  
    Print "Accommodation = " & A & " Diopters" -{L[Wt{1  
    Print "Pupil Diameter = " & pupilDiam & " mm" $fC=v  
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    ' Calculate new parameters with accommodation },[j+wx  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness XM8C{I1  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens %C)U F  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens }A2@1TTPX  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Iqo4INGIi  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens t3bDi/m  
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    tlens = 3.767 + 0.04*A                  'Lens thickness S)Ld^0w  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction M}@^8  
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    'Adjust parameters to account for accommodation UGR5ILf  
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    '************************************************************************* Jnv91*>h8  
    'Aqueous thickness (Position of Lens) TXy*-<#vR  
    '************************************************************************* Vw)\#6FL  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) n}?kQOg0/  
    GetCustomElement eID, entity |4-
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    parID = FindFullName( "Geometry.Arizona Eye" ) _G'.VSGH  
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    ' Delete any shift(s) in z 1S_KX.  
    count = 0 ^s24f?3  
    While GetOperationCount(eID)>count WddU|-W  
        GetOperation eID, count, op 0>.'w\,87B  
        If op.Type="ShiftZ" Then o*dhks[  
            DeleteOperation eID,count Hj2P|;2S  
            count=count-1 9$d (`-&9p  
        End If cJH7zumM)  
        count=count+1 Z/ThYbk  
    Wend ew"[]eZ:ut  
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    'Set new shift in VY![VnHsB  
    op.Type = "ShiftZ" flmcY7ZV  
    op.val1 = taq 1uD}V7_y"  
    op.parent = parID s'5 jvlG  
    AddOperation eID, op $]%k <|X  
    Print "Set aqueous humor thickness = " & taq-0.55 Kk??}  
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    '************************************************************************* Dcp,9"yt%  
    'Radius and conic constant of anterior lens 4NbC V)Dm  
    '************************************************************************* r9u
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    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) x&8?/BR  
    GetConic eID, entity, curv, conic U(i2j)|^I3  
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    SetConic eID, entity, 1/Rant, CCant T>LtN  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Xv'64Nc!;  
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    '*************************************************************************
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    'Radius and conic constant of posterior lens 3EzI~Zsx  
    '************************************************************************* =8<SKY&\X  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 47t^{WrT  
    GetConic eID, entity, curv, conic ql_aDoj  

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    SetConic eID, entity, 1/Rpost, CCpost [9$>N  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost XFM6.ye  
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    '************************************************************************* sg9ZYWcL  
    'Lens thickness (Position of posterior lens surface) p%,JWZ[  
    '************************************************************************* O0~[]3Y[=  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) zzPgLE55  
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    ' Delete any z-shift(s) BeplS  
    count = 0 `cVG_=2  
    While GetOperationCount(eID)>count v|n.AGn  
        GetOperation eID, count, op GL (YC-{  
        If op.Type="ShiftZ" Then WRD^S:`BH  
            DeleteOperation eID,count D4 e)v%  
            count=count-1 BDcl1f T  
        End If (+T|B E3*#  
        count=count+1 TNiFl hq  
    Wend ^8We}bs-c  
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    'Set new z-shift GKm)wOb(*S  
    op.Type = "ShiftZ" m#8mU,7  
    op.val1 = tlens @0t,vye  
    op.parent = parID !QC->  
    AddOperation eID, op S* <:He&1  
    Print "Set lens thickness = " & tlens K4oLb"gB1  
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    '************************************************************************* t'7)aJMP  
    'Lens index of refraction |%TH|?kB  
    '************************************************************************* CQ13fu+|6  
    eID = FindMaterial( "Lens" ) 3D%I=p(  
    GetModelMaterial eID, mat  +/AW6  
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    mat.Nd = nlens "y5c)l(Rg  
    SetModelMaterial eID, mat Soq 'B?>  
    Print "Set lens index of refraction = " & nlens \}G/F
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    '************************************************************************* B&<Z#C:I  
    'Pupil diameter 
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    '************************************************************************* 8Gs{Zfp!D  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ? NVN&zD]  
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    'Adjust pupil diameter (trimming volume inner hole) r=s2wjk  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" OSsdB%bIu`  
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    ' Adjust pupil location to just in front of the lens kjjO<x?&*  
    parID = FindFullName( "Geometry.Arizona Eye" ) VxaJ[s3PQ&  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Pm V:J9  
    count = 0 zq(AN<  
    While GetOperationCount(eID)>count +dIg&}Tr  
        GetOperation eID, count, op C\ 9eR  
        If op.Type="ShiftZ" Then H?^Poe(=(  
            DeleteOperation eID,count %0=|WnF-  
            count=count-1 c1!h;(&  
        End If -pyTzC$HO  
        count=count+1 ={8ClUV#  
    Wend Smg,1,=  
    op.Type = "ShiftZ" \%rX~UhZ=  
    op.val1 = taq-0.01 lHr?sMt
 
    op.parent = parID c00a;=ji  
    AddOperation eID, op 0FH
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    Print "Set pupil diameter = " & pupilDiam lYD-
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    'Update AZ Eye subassembly Description 57rc|]C  
    eID = FindFullName( "Geometry.Arizona Eye" ) ,in`JM<o  
    GetEntity eID, entity $)z(4Ev  
    entity.Description = "Accommodation = " & A & "D" *|ubH?71%Y  
    SetEntity eID, entity ~B|K]&/]  
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    Update dk-Y!RfNx  
    Print "DONE!" 8^^Xr  
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End Sub {N/(lB8  
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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： jt=mK,%  
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Accommodation = 4 Diopters -
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Pupil Diameter = 4 mm XwE(&ZCf'b  
Set aqueous humor thickness = 2.81 Pr<.ld\  
Set anterior lens radius = 10.4 and conic constant = -2.375869 S0,p:Wey  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 $hn#T#J3  
Set lens thickness = 3.927 Ryr2  
Set lens index of refraction = 1.42672 VuPa'2  
Set pupil diameter = 4 YN.rj-;^+  
DONE! [f&ja[m q  
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