[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 @@K@;Jox  
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。 X9C)FS  
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模型 Yf >SV #  
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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。 q1a}o%  
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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. de]r9$D  
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光源 }yCJ#}  
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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。 "f\2/4EIl  
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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。 -]"=b\Q  
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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。 l^4[;%*f#l  

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视网膜的散射 &\8.y2=9p  
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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。 1><\
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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。 T5_z^7d  
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脚本 _KiaeVE  

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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： "8|y  
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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。 Srj%6rgsB  
余下的脚本计算与屈光度有关的所有参数。 f'aQ T  
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分析 9i@AOU  
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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。 tdg.vYMDPC  
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脚本代码 6dTq&GZ\  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. k7P~*ll$  
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Dim entity As T_ENTITY :0>wm@qCQ  
Dim op As T_OPERATION @-~YQ@08`  
Dim mat As T_MODELMATERIAL X&DuX %x0  
Dim A As Double n m(yFX?=  
Dim pupilDiam As Double 
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Dim eID As Long QxvxeK!Y  
Dim parID As Long TuY{c%qQ:  
Dim count As Integer Y'"2s~_ Z  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double ;SkC[;`J  
Dim tlens As Double, nlens As Double )%%RI_JT  
Dim curv As Double, conic As Double WmLl.Vv=  
Dim ok As Long |Axg}Q|  
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Sub Main 0?l|A1I%  
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    '用户输入对话框 vFY/o,b \  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 j~c7nWfX  
        TextBox 220,21,40,21,.TextBox1 'default: 0 XPXC7_fV  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 YXXUYi~!f  
        OKButton 40,91,90,21 p%Ae"#_X%  
        CancelButton 190,91,90,21 EAo7(
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        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 I2("p.+R  
        TextBox 220,49,40,21,.TextBox2 'default: 4 bT-(lIU  
    End Dialog "lLt=s2>L  
    Dim dlg As UserDialog At%g^  
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    ok = Dialog (dlg) (FZL>  
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    If ok=0 Then    'cancel button was pressed @va{&i`%A7  
        Print "Execution cancelled." A=|LMJMWR  
        End q]:+0~cz  
    End If #/sKb2eQ  
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    'Assign accommodation and pupil diameter & use defaults if field left empty o1"U'y-9V  
    If dlg.TextBox1 = "" Then h*)spwF-  
        A = 0           'Default accommodation kac@yQD  
    Else YD2M<.U  
        A = CDbl(dlg.TextBox1) >#dNXH]9  
    End If ^ef:cS$;  
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    If dlg.TextBox2 = "" Then xr!FDfM.K  
        pupilDiam = 4   'Default pupil diameter ]g3&gw  
    Else oju/%ieh  
        pupilDiam = CDbl(dlg.TextBox2) 3O%[k<S\VO  
    End If CU6rw+Vax  
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    Print " " e.G&hJr  
    Print "Accommodation = " & A & " Diopters" wM(!9Ws3  
    Print "Pupil Diameter = " & pupilDiam & " mm" y% uUA]c*m  
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    ' Calculate new parameters with accommodation iKV;>gF,)v  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 2j-|.l c  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens '1ff|c!x9  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 8kAG EiC  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens td q;D  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ~FH''}3:3
 
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    tlens = 3.767 + 0.04*A                  'Lens thickness ?v#t{e0eQ  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction n5 @H  
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    'Adjust parameters to account for accommodation xZtA
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    '************************************************************************* QV+('  
    'Aqueous thickness (Position of Lens) 1mL--m'r  
    '************************************************************************* ckP&N:tC  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) g
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    GetCustomElement eID, entity p}uL%:Vr  
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    parID = FindFullName( "Geometry.Arizona Eye" ) }CaL:kY8  
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    ' Delete any shift(s) in z k<"ZNQm$.  
    count = 0 ~t<BZu  
    While GetOperationCount(eID)>count Y1{6lhxgE  
        GetOperation eID, count, op f|?i6.N>f  
        If op.Type="ShiftZ" Then )Be}Ev#)Zx  
            DeleteOperation eID,count nE]R0|4h  
            count=count-1 y_qFX
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        End If CeR4's7  
        count=count+1 gO<>L0,j  
    Wend .zlUN0oe  
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    'Set new shift in %whPTc0P  
    op.Type = "ShiftZ" / !jd%,G  
    op.val1 = taq o&rejj#  
    op.parent = parID e.\d7_T+  
    AddOperation eID, op 4&K~EX"^T  
    Print "Set aqueous humor thickness = " & taq-0.55 W3{k{~  
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    '************************************************************************* ,":ADO-  
    'Radius and conic constant of anterior lens )eY3[>`  
    '************************************************************************* RFDwL~-p  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) )Y Qtrc\91  
    GetConic eID, entity, curv, conic L\nWhmwl  
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    SetConic eID, entity, 1/Rant, CCant & @^|=>L  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant pb$U~TvzhM  
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    '************************************************************************* Jnb>u*7,  
    'Radius and conic constant of posterior lens _(<[!c!@0  
    '************************************************************************* 6T"[M  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) qW][Q%'lt  
    GetConic eID, entity, curv, conic Z)|*mJ  
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    SetConic eID, entity, 1/Rpost, CCpost
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost "%<Oadz ap  
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    '************************************************************************* !(w\%$|  
    'Lens thickness (Position of posterior lens surface) xO'1|b^&  
    '************************************************************************* wR@fB  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 8>T '  
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    ' Delete any z-shift(s) K)sO  
    count = 0 _Wk!d3bsx  
    While GetOperationCount(eID)>count rQ;m|@  
        GetOperation eID, count, op <{3VK  
        If op.Type="ShiftZ" Then E{_p&FF  
            DeleteOperation eID,count (lwkg8WC  
            count=count-1 }Wn6r_:  
        End If 5bH@R@3m  
        count=count+1 bMxzJRrNg  
    Wend IpB0~`7YI  
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    'Set new z-shift :?U1^!$$1  
    op.Type = "ShiftZ" tlCgW)<?  
    op.val1 = tlens Tr(w~et  
    op.parent = parID * "~^k^_b}  
    AddOperation eID, op ljlQ9wb[s  
    Print "Set lens thickness = " & tlens V!DQ_T+a  
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    '************************************************************************* 0{@E=}}h  
    'Lens index of refraction O6YYOmt3  
    '************************************************************************* tegLGp@_  
    eID = FindMaterial( "Lens" ) 3O:Z;YP:<  
    GetModelMaterial eID, mat 7$\;G82_  
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    mat.Nd = nlens = =cAL"Z  
    SetModelMaterial eID, mat <nvz*s  
    Print "Set lens index of refraction = " & nlens ql2>C.k3L  
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    '************************************************************************* hof:36 <  
    'Pupil diameter R}#?A%,*  
    '************************************************************************* ^^{K[sLB  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) t1 OnA#]/_  
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    'Adjust pupil diameter (trimming volume inner hole) tOn/r@Fd^E  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" <omSK- T
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    ' Adjust pupil location to just in front of the lens 38tRb"3zP  
    parID = FindFullName( "Geometry.Arizona Eye" ) dArg'Dc4  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) G9 ;X=
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    count = 0 Elom_   
    While GetOperationCount(eID)>count {<v?Z_!68  
        GetOperation eID, count, op GASDkVoij  
        If op.Type="ShiftZ" Then <2fZYt vt  
            DeleteOperation eID,count -L NJ*?b  
            count=count-1 Ev,>_1#Xm  
        End If uv%T0JA/  
        count=count+1 ]L"jt8E  
    Wend jav7V"$  
    op.Type = "ShiftZ" 0/6f9A  
    op.val1 = taq-0.01 h rW  
    op.parent = parID ,gVA^]eDh  
    AddOperation eID, op 9G[!"eZ}  
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    Print "Set pupil diameter = " & pupilDiam D. fPHq  
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    'Update AZ Eye subassembly Description Eh^c4x  
    eID = FindFullName( "Geometry.Arizona Eye" ) [6`8^-}?  
    GetEntity eID, entity ': 87.8$  
    entity.Description = "Accommodation = " & A & "D" yTm/P!1S  
    SetEntity eID, entity H{x'I@+  
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    Update <~X4&E]rT_  
    Print "DONE!" ]u?|3y^(  
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End Sub 66(|3DX  
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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： @SjISZw_  
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Accommodation = 4 Diopters <U%4$83$  
Pupil Diameter = 4 mm i882r=TE3  
Set aqueous humor thickness = 2.81 J: vq)G\F  
Set anterior lens radius = 10.4 and conic constant = -2.375869 I<L  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 -GJ~xcf0  
Set lens thickness = 3.927 Ngi]I#Vz  
Set lens index of refraction = 1.42672 wj!YYBH  
Set pupil diameter = 4 !'8.qs  
DONE! wW EnAW~  
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