[技术]Arizona眼睛模型 [复制链接]

简介 r+W8m?oi  
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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。 eABdye  
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模型 (Q p]0  
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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。 Lq8Z!AIw>  
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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. 3M:B?2  
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光源 JI#Enh!Lv  
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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。 HZQ3Ht3Vh  
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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。 uP'w.nA&2  
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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。 3
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视网膜的散射 a>jI_)L  
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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。 `h{mj|~  
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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。 dcTM02kEh  
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脚本 F0^~YYRJV  
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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： ,(kXF:  
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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。 >xMhA`
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余下的脚本计算与屈光度有关的所有参数。 ysn[-l#  
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分析 "?(Fb
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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。 v?"ee&Y6  
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脚本代码 MxA'T(Ay  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. v5ddb)  
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Dim entity As T_ENTITY {%~Ec4r  
Dim op As T_OPERATION s31_3?Vdf,  
Dim mat As T_MODELMATERIAL ew ,edU  
Dim A As Double BU{V,|10a  
Dim pupilDiam As Double ]=VI"v<X  
Dim eID As Long _q}%!#4  
Dim parID As Long $ttr_4=  
Dim count As Integer \@" . GM%  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double eZkz 1j~  
Dim tlens As Double, nlens As Double c)YGwkY,,  
Dim curv As Double, conic As Double <Y'YpH`l  
Dim ok As Long \I{A33i2w  
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Sub Main 6]49kHgMhe  
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    '用户输入对话框 ,/U9v~  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Rk0rHC6[  
        TextBox 220,21,40,21,.TextBox1 'default: 0 \-id[zKb  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 )cBV; E<  
        OKButton 40,91,90,21 U4pvQE.m<  
        CancelButton 190,91,90,21 A'R sy6  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 IoX9yGq  
        TextBox 220,49,40,21,.TextBox2 'default: 4 \uIC<#o"N  
    End Dialog y9 '3vZ  
    Dim dlg As UserDialog ADUI@#vk  
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    ok = Dialog (dlg) p{PYUW"?^  
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    If ok=0 Then    'cancel button was pressed go Z#  
        Print "Execution cancelled." B\w`)c  
        End LA0x6E+I  
    End If BJrNbo;T  
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    'Assign accommodation and pupil diameter & use defaults if field left empty m,q<R1  
    If dlg.TextBox1 = "" Then :|Ty 0>k  
        A = 0           'Default accommodation F+r6/e6a  
    Else d7gSkna`5c  
        A = CDbl(dlg.TextBox1) ^yZEpQN_  
    End If 'FXZ`+r|  
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    If dlg.TextBox2 = "" Then }PuO$ L  
        pupilDiam = 4   'Default pupil diameter 7!)%%K.z6  
    Else E/ )+hK&  
        pupilDiam = CDbl(dlg.TextBox2) oI
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    End If |th )Q  
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    Print " " |sAg@kM  
    Print "Accommodation = " & A & " Diopters" UGgi)  
    Print "Pupil Diameter = " & pupilDiam & " mm" 31Du@h8YX  
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    ' Calculate new parameters with accommodation C"WZsF^3  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness gH.^NO5\'  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens {`55nwd  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens u9(AT>HxT  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens \)WjkhG<w#  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens D._r@~o  
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    tlens = 3.767 + 0.04*A                  'Lens thickness .ji%%f  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction $!w%=  
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    'Adjust parameters to account for accommodation Bw[VK7  
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    '************************************************************************* 2ra4t]f6  
    'Aqueous thickness (Position of Lens) RPwSo.c4
 
    '************************************************************************* {lJpcS  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) zZ-*/THB@R  
    GetCustomElement eID, entity $la,_Sr  
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    parID = FindFullName( "Geometry.Arizona Eye" ) dZZ/(oE>  
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    ' Delete any shift(s) in z &baY[[N  
    count = 0 g.Q ?Z{  
    While GetOperationCount(eID)>count KivzgNz  
        GetOperation eID, count, op C/G[B?:h  
        If op.Type="ShiftZ" Then 'z/hj>B<  
            DeleteOperation eID,count zT8K})#  
            count=count-1 H#K|SSqY?  
        End If ^gImb`<6-  
        count=count+1 IT|CfQ [D  
    Wend X,~C&#  
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    'Set new shift in ~7g6o^A>  
    op.Type = "ShiftZ" F
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    op.val1 = taq
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    op.parent = parID '"Gi&:*nQ<  
    AddOperation eID, op e6Y0
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    Print "Set aqueous humor thickness = " & taq-0.55 t*#T
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    '************************************************************************* D@e:Fu1\R  
    'Radius and conic constant of anterior lens KMa?2cJH#  
    '************************************************************************* LJ?7W,?  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) fqxMTTg@  
    GetConic eID, entity, curv, conic TQE_zOa:  
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    SetConic eID, entity, 1/Rant, CCant 2\n6XAQ*  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant a9%# J^!  
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    '************************************************************************* .vg
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    'Radius and conic constant of posterior lens Gwe9< y  
    '************************************************************************* ^<c?Ire  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) V.qB3V$  
    GetConic eID, entity, curv, conic \TjsXy=:)  
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    SetConic eID, entity, 1/Rpost, CCpost 3~ylBJJ  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ;IyQqP#,<  
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    '************************************************************************* [||$1
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    'Lens thickness (Position of posterior lens surface) *=rl<?tX  
    '************************************************************************* {>#Ya;E  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) $P$OWp?b  
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    ' Delete any z-shift(s) ~O!v?2it8q  
    count = 0 *5^h>Vk/  
    While GetOperationCount(eID)>count ]'Bz%[C)  
        GetOperation eID, count, op M%m$5[;n  
        If op.Type="ShiftZ" Then k2~j:&p  
            DeleteOperation eID,count iVE+c"c!2&  
            count=count-1 +NQw^!0qy  
        End If rRxqV?>n!  
        count=count+1 ,xGkE7=5  
    Wend ?(Nls.c  
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    'Set new z-shift :EZTJu  
    op.Type = "ShiftZ" Gmc
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    op.val1 = tlens z' @F@k6  
    op.parent = parID =73wngw  
    AddOperation eID, op yA~W|q(/V  
    Print "Set lens thickness = " & tlens Tw$lakw  
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    '************************************************************************* DF<_
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    'Lens index of refraction b1-JnEc  
    '************************************************************************* h<[o;E  
    eID = FindMaterial( "Lens" ) Xcb\N  
    GetModelMaterial eID, mat ,{$:Q}`  
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    mat.Nd = nlens "[76>\'H  
    SetModelMaterial eID, mat Y>r9"X|&H  
    Print "Set lens index of refraction = " & nlens k z<We/  
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    '************************************************************************* AkGCIn3  
    'Pupil diameter E1=]m  
    '************************************************************************* M^a QH/=:"  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ~Os~pTo  
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    'Adjust pupil diameter (trimming volume inner hole) P7Kp*He)  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" H'GyWG|Wx  
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    ' Adjust pupil location to just in front of the lens $Ad 5hkz  
    parID = FindFullName( "Geometry.Arizona Eye" ) 7cH[}v`pn  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) xI$B",?(  
    count = 0 .Gw;]s3  
    While GetOperationCount(eID)>count $5l8V  
        GetOperation eID, count, op ]h,XRDK  
        If op.Type="ShiftZ" Then '~2;WF0h  
            DeleteOperation eID,count L9(fa+$+#  
            count=count-1 ?Yxk1Y4ig)  
        End If -W2 !_  
        count=count+1 r\Zz=~![<  
    Wend >J+hu;I5  
    op.Type = "ShiftZ" pno]Bld'z  
    op.val1 = taq-0.01 5P [b/.n  
    op.parent = parID >zVj+  
    AddOperation eID, op &jr'vS[b  
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    Print "Set pupil diameter = " & pupilDiam t0(1qFi  
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    'Update AZ Eye subassembly Description 6Dwj^e0  
    eID = FindFullName( "Geometry.Arizona Eye" ) 1d,;e:=j  
    GetEntity eID, entity W&qE_r  
    entity.Description = "Accommodation = " & A & "D" Vv#|%^0  
    SetEntity eID, entity WbB0{s  
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    Update G<U MZg  
    Print "DONE!" blEs!/A`  
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End Sub F<VoPqHq  
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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： sz9C':`W  
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Accommodation = 4 Diopters #**vIwX-Q  
Pupil Diameter = 4 mm |5^tp  
Set aqueous humor thickness = 2.81 9q(*'rAm  
Set anterior lens radius = 10.4 and conic constant = -2.375869 -AWL :<  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 LR|LP)I  
Set lens thickness = 3.927 Z(k7&^d  
Set lens index of refraction = 1.42672 [9Q}e;T  
Set pupil diameter = 4 5ELKL#(  
DONE! &;I=*B~kE$