[技术]Arizona眼睛模型 [复制链接]

简介 gR#lRA/  
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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。 + 7~u_J  
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模型 RX\l4H5;  
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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。 XLq%nVBM8\  
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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.
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光源 n97pxD_74  
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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。 OL0W'C9oA  
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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(9mnZ1  
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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。 A8jj]J+  
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视网膜的散射 40i]I@:JK  
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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。 %V;B{?>9zB  
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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。 N)0V6q"  
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脚本 '2=$pw  
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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： IMT]!j&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。 XhEJF !  
余下的脚本计算与屈光度有关的所有参数。 [!'fE#"a  
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分析 )&pcRFl  
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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。 D\CjR6DE  
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脚本代码 *^=zQ~  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. q1_iV.G<  
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Dim entity As T_ENTITY
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Dim op As T_OPERATION ih\
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Dim mat As T_MODELMATERIAL A.wuB  
Dim A As Double M9ACaf@  
Dim pupilDiam As Double s+a} _a:  
Dim eID As Long -:~"c@D  
Dim parID As Long v3I-i|L<)  
Dim count As Integer X :wfm
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Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double |g1~-  
Dim tlens As Double, nlens As Double hgPzx@  
Dim curv As Double, conic As Double *w,C5 f  
Dim ok As Long ww#]i&6  
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Sub Main QXLHQ_V  
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    '用户输入对话框 EZb_8<DH  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 yNDplm|9*  
        TextBox 220,21,40,21,.TextBox1 'default: 0 L<H zPg  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 $z \H*
  
        OKButton 40,91,90,21 B$D7}=|kc  
        CancelButton 190,91,90,21 0T7c=5z4W  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 < ?{ic2j#  
        TextBox 220,49,40,21,.TextBox2 'default: 4 al@H
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    End Dialog `E:&a]ul  
    Dim dlg As UserDialog J*nWCL  
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    ok = Dialog (dlg) I:=rwnd  
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    If ok=0 Then    'cancel button was pressed /+JHnedK  
        Print "Execution cancelled." 2|}`?bY]i`  
        End 2uT"LW/(H  
    End If mO8E-D*3  
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    'Assign accommodation and pupil diameter & use defaults if field left empty p"tCMB  
    If dlg.TextBox1 = "" Then 4Gor*
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        A = 0           'Default accommodation )Rc  
    Else z;Yo76P  
        A = CDbl(dlg.TextBox1) ]9hXiY  
    End If y*7{S{9  
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    If dlg.TextBox2 = "" Then -J]j=  
        pupilDiam = 4   'Default pupil diameter }-N4D"d4o  
    Else |y.^F3PE  
        pupilDiam = CDbl(dlg.TextBox2) H{U(Rt]
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    End If kkU#0p?7  
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    Print " " z{wZLqG  
    Print "Accommodation = " & A & " Diopters" vp&N)t_  
    Print "Pupil Diameter = " & pupilDiam & " mm" _h^er+d
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    ' Calculate new parameters with accommodation cTa$t :K@  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Lu5lpeSQ  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens =Ohro'   
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens =HHtLW.|,  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens )z!#8s  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens k<A|+![  
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    tlens = 3.767 + 0.04*A                  'Lens thickness HyYol*  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction F#KUu3;B  
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    'Adjust parameters to account for accommodation pF<KhE*V  
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    '************************************************************************* 5
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    'Aqueous thickness (Position of Lens) TR'<D9kn  
    '************************************************************************* &1FyauH  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ;U[W $w[  
    GetCustomElement eID, entity %(A@=0r#  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 2Kz407|'  
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    ' Delete any shift(s) in z %0q)PT\  
    count = 0 R/P9=yvg0  
    While GetOperationCount(eID)>count 8SOfX^;o  
        GetOperation eID, count, op 7bL48W<QD  
        If op.Type="ShiftZ" Then OLE@35"v]  
            DeleteOperation eID,count ge|Cvv  
            count=count-1 CF]#0*MI  
        End If FV\$M6 _  
        count=count+1 )^7- qy  
    Wend 3(3-#MD0  
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    'Set new shift in ]zh6[0V7V  
    op.Type = "ShiftZ" of/' 9Tj  
    op.val1 = taq 48LzI@H&  
    op.parent = parID 4$^rzAi5  
    AddOperation eID, op o+g\\5s  
    Print "Set aqueous humor thickness = " & taq-0.55 /NUu^ N  
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    '************************************************************************* seiE2F[  
    'Radius and conic constant of anterior lens xG:7AGZ$[  
    '************************************************************************* LX</xI08W  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) sWFw[Y>  
    GetConic eID, entity, curv, conic IPk"{
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    SetConic eID, entity, 1/Rant, CCant %o_CD>yD  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant
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    '************************************************************************* !m?W+z~J  
    'Radius and conic constant of posterior lens 5!qLJmd=  
    '************************************************************************* ,U=7#Cf!  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) @vPGkM#oW  
    GetConic eID, entity, curv, conic _Kg"l5?B  
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    SetConic eID, entity, 1/Rpost, CCpost N >k,"=N/  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost YJ{_%z|U  
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    '************************************************************************* +t}<e(  
    'Lens thickness (Position of posterior lens surface) b X4]/4%  
    '************************************************************************* Idr|-s%l6'  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 0pA>w8mh  
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    ' Delete any z-shift(s) lFD/hz7lc  
    count = 0 M7c53fz  
    While GetOperationCount(eID)>count Y*YV/E.  
        GetOperation eID, count, op pXf5/u8&  
        If op.Type="ShiftZ" Then QA#Jx  
            DeleteOperation eID,count :s#&nY  
            count=count-1 jN{+$ @cI  
        End If c:,K{ZR  
        count=count+1 J-W8wCq`  
    Wend =z9FjK  
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    'Set new z-shift YiC
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    op.Type = "ShiftZ" ~i=5NUE  
    op.val1 = tlens 2fG[q3`  
    op.parent = parID j]  
    AddOperation eID, op +A<7:`sO  
    Print "Set lens thickness = " & tlens e@L?jBj8m  
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    '************************************************************************* iQz c$y^,9  
    'Lens index of refraction ^A$p)`KR  
    '************************************************************************* *7K)J8kq  
    eID = FindMaterial( "Lens" ) gF&HJF 0x  
    GetModelMaterial eID, mat H~~>ut6`  
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    mat.Nd = nlens e! 0Y`lQ  
    SetModelMaterial eID, mat #RP7?yGM,  
    Print "Set lens index of refraction = " & nlens !\|L(Paf  
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    '************************************************************************* Te@=8-u-  
    'Pupil diameter CxJH)H$  
    '************************************************************************* RaAvPIJa |  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) -4t!k Aw`  
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    'Adjust pupil diameter (trimming volume inner hole) V,>uM >$  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" %$zX a%A  
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    ' Adjust pupil location to just in front of the lens kcZz WG|n  
    parID = FindFullName( "Geometry.Arizona Eye" ) S3&lkN5  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Cm[^+.=I  
    count = 0 qh/}/Sl;  
    While GetOperationCount(eID)>count 7=pJ)4;ZA  
        GetOperation eID, count, op Q#sLIZ8=  
        If op.Type="ShiftZ" Then kqp*o+Oz',  
            DeleteOperation eID,count |H4f&&Wd  
            count=count-1 g:fzf>oQ>p  
        End If j(];b+>  
        count=count+1 3L-}B#tI  
    Wend _2nNCu (  
    op.Type = "ShiftZ" gBJM|"_A
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    op.val1 = taq-0.01 z#t;n  
    op.parent = parID
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    AddOperation eID, op j4!oBSp  
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    Print "Set pupil diameter = " & pupilDiam "oo j;  
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    'Update AZ Eye subassembly Description Oh/2$72  
    eID = FindFullName( "Geometry.Arizona Eye" ) dnstm@0k  
    GetEntity eID, entity 5Jm%*Wb  
    entity.Description = "Accommodation = " & A & "D" Wf5ohXm>  
    SetEntity eID, entity m>LC2S; f  
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    Update D|X@aUp8}  
    Print "DONE!" !&@
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End Sub GB` G(a  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： 7N I~47s|v  
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Accommodation = 4 Diopters a29rD$  
Pupil Diameter = 4 mm &l2C-(  
Set aqueous humor thickness = 2.81 SZm&2~|J  
Set anterior lens radius = 10.4 and conic constant = -2.375869 aW7)}"j4  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 9zD^4j7  
Set lens thickness = 3.927 6YpP/ K  
Set lens index of refraction = 1.42672 8ZvozQE  
Set pupil diameter = 4 t+m ug  
DONE! iBy &#^