[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 \p@,+ -gX  
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。 ERGDo=j  
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模型 %nOBsl
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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。  O\]CfzR  
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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. AWQwpaj-  
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光源 1uMnlimr  
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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。 )J~Qx-jG  
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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。 yW|yZ(7  
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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。 I g-VSQ  
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视网膜的散射 qdZn9i  
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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。 RS<c&{?  
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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。 NqhRJa63  
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脚本 4y 582u6^  
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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： X?4
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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。 _Mq@58q'  
余下的脚本计算与屈光度有关的所有参数。 2c8,H29  
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分析 u"pn'H  
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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。 _k5KJKvr  
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脚本代码 JO+ hD4L  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. nV:.-JR  
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Dim entity As T_ENTITY UvQxtT]  
Dim op As T_OPERATION r^*,eF  
Dim mat As T_MODELMATERIAL _e~EQ[,  
Dim A As Double O_F<VV*MFQ  
Dim pupilDiam As Double Fo?2nQ<  
Dim eID As Long x0Tb7y`  
Dim parID As Long m&2<?a}l  
Dim count As Integer <ezvz..g  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double $D9JsUij  
Dim tlens As Double, nlens As Double PJA 1/"  
Dim curv As Double, conic As Double J"6_H =s   
Dim ok As Long zUwz[^d<C  
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Sub Main !i)?j@D  
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    '用户输入对话框 r<&d1fM;X  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 z${B|  
        TextBox 220,21,40,21,.TextBox1 'default: 0 De4+4&  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 *QjFrw3  
        OKButton 40,91,90,21 +Icg;m{  
        CancelButton 190,91,90,21 U6.$F#n  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1
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        TextBox 220,49,40,21,.TextBox2 'default: 4 =H!u4  
    End Dialog ?"qU.}kGL  
    Dim dlg As UserDialog #<v3G)|aS  
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    ok = Dialog (dlg) lQ!6n  
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    If ok=0 Then    'cancel button was pressed !Otyu6&  
        Print "Execution cancelled." $[FO(w@f  
        End lXv{+ic  
    End If lg1?g)lv  
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    'Assign accommodation and pupil diameter & use defaults if field left empty x8zUGvtQ  
    If dlg.TextBox1 = "" Then gfih;i.pY  
        A = 0           'Default accommodation Dyt}"r\  
    Else -f Zm_FE  
        A = CDbl(dlg.TextBox1) ,Y9lp)w  
    End If 7*@qd&  
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    If dlg.TextBox2 = "" Then $+7MY-9T  
        pupilDiam = 4   'Default pupil diameter fS!%qr  
    Else ,pf<"^li  
        pupilDiam = CDbl(dlg.TextBox2) bX5>qqB]  
    End If LRB#|PW  

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    Print " " /0"Y. @L  
    Print "Accommodation = " & A & " Diopters" _Y}(v((;  
    Print "Pupil Diameter = " & pupilDiam & " mm" ]_F%{8|  
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    ' Calculate new parameters with accommodation HRPTP+  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness uWi+F)GS^K  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 10}\7p8  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens Et`z7Q*e  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens m./lrz  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens *PZNZ{|m  
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    tlens = 3.767 + 0.04*A                  'Lens thickness {T m-X`  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction kQ{pFFO  
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    'Adjust parameters to account for accommodation h7I_{v8  
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    '************************************************************************* yy/wSk  
    'Aqueous thickness (Position of Lens) <P}{0Y~@*W  
    '************************************************************************* b/5;377_  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 
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    GetCustomElement eID, entity eNN%%Q  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 0I~xD9l9  
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    ' Delete any shift(s) in z y=5s~7]  
    count = 0 wdl6dLu  
    While GetOperationCount(eID)>count . (Q;EF`_U  
        GetOperation eID, count, op nmS3  
        If op.Type="ShiftZ" Then 0=L:8&m  
            DeleteOperation eID,count /`}C
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            count=count-1 bWUo(B#*I  
        End If }_gCWz-5?  
        count=count+1 8Ay#6o  
    Wend KuE 2a,E4  
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    'Set new shift in jyLpe2 S  
    op.Type = "ShiftZ" fLct!H3  
    op.val1 = taq !=|3^A  
    op.parent = parID QjF.U8  
    AddOperation eID, op u|O5ZV-cd  
    Print "Set aqueous humor thickness = " & taq-0.55 i nF&Pv  
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    '************************************************************************* .5KRi6  
    'Radius and conic constant of anterior lens MDl  
    '************************************************************************* ]%ikr&78u  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 9'td}S  
    GetConic eID, entity, curv, conic O^F%ssF8  
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    SetConic eID, entity, 1/Rant, CCant 2vu"PeU9  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant pbR84g^p.S  
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    '************************************************************************* Lt|k}p@]  
    'Radius and conic constant of posterior lens SYeCz(H>d  
    '************************************************************************* WLv( K_3Y  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) jO<K0cc  
    GetConic eID, entity, curv, conic +%$!sp?  
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    SetConic eID, entity, 1/Rpost, CCpost p,$1%/m  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost rsOon2|  
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    '************************************************************************* F+*: >@3  
    'Lens thickness (Position of posterior lens surface) K?(ls$  
    '************************************************************************* k]ptk^  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) nPR_:_^  
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    ' Delete any z-shift(s) -"<H$  
    count = 0 9@:H9"w  
    While GetOperationCount(eID)>count 9\R:J"X  
        GetOperation eID, count, op >c5Vz^uM{4  
        If op.Type="ShiftZ" Then W>bhSKV%  
            DeleteOperation eID,count o5i?|HJ  
            count=count-1 cQ1oy-paD  
        End If Z\6azhbI}  
        count=count+1 $9M>B<]  
    Wend ;BejFcb  
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    'Set new z-shift oT5?*3f  
    op.Type = "ShiftZ" v^HDR 3I  
    op.val1 = tlens M)Vz9,  
    op.parent = parID }\OLBg/  
    AddOperation eID, op {~[H"h537t  
    Print "Set lens thickness = " & tlens < 5;0LPU  
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    '************************************************************************* mQ('X~l  
    'Lens index of refraction zPH1{|H+l  
    '************************************************************************* q'hMf?_  
    eID = FindMaterial( "Lens" ) l/DV ?27  
    GetModelMaterial eID, mat =_D82`
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    mat.Nd = nlens t A\N$  
    SetModelMaterial eID, mat iG6 ^s62z7  
    Print "Set lens index of refraction = " & nlens i8Yl1nF  
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    '************************************************************************* zTAt% w5  
    'Pupil diameter xAjLn*d|N  
    '************************************************************************* "z=A=~~<{  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Qh? E*9  
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    'Adjust pupil diameter (trimming volume inner hole) slDxsb  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" os/~6  
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    ' Adjust pupil location to just in front of the lens C ])Q#!D|  
    parID = FindFullName( "Geometry.Arizona Eye" ) dY;^JPT  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) dV<M$+;s]  
    count = 0 wI1[I  
    While GetOperationCount(eID)>count 5#80`/w^U  
        GetOperation eID, count, op one^XYy1%  
        If op.Type="ShiftZ" Then Y H 2iV  
            DeleteOperation eID,count t TA6 p  
            count=count-1 MN$j{+!Q  
        End If zt[TS
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        count=count+1  +h9UV  
    Wend E,c~.jYc  
    op.Type = "ShiftZ" YRG+I GX  
    op.val1 = taq-0.01 =<
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    op.parent = parID ^W_}Gd<-#Y  
    AddOperation eID, op YQ,IdWav  
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    Print "Set pupil diameter = " & pupilDiam #_2V@F+,  
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    'Update AZ Eye subassembly Description SjtGU47$!  
    eID = FindFullName( "Geometry.Arizona Eye" ) @Sq=#f/=  
    GetEntity eID, entity hO;bnt%(  
    entity.Description = "Accommodation = " & A & "D" )N)ziAy}  
    SetEntity eID, entity \CUxGyu  
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    Update S/~6%uJ  
    Print "DONE!" C;dA?Es>R  
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End Sub $rFv(Qc^=  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： rJ\A)O+Mq(  
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Accommodation = 4 Diopters ^}/YGAA  
Pupil Diameter = 4 mm j@GMZz<  
Set aqueous humor thickness = 2.81 k_P`t[YZV  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ^3=8*Xr  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 /rvXCA)j  
Set lens thickness = 3.927 (g7nMrE$j  
Set lens index of refraction = 1.42672 Mh~T.;f.qq  
Set pupil diameter = 4 B1nb23SY T  
DONE! Z]w_2- -  
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