[技术]Arizona眼睛模型 [复制链接]

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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。 csF!*!tta  
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模型 9@."Y>1G  
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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。 ^N5BJ'[F:  
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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. aGY
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光源 l[q%1-N  
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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。 =@d IM  
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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。 e)~7pXYV)  
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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。 HV??B :  
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视网膜的散射 Jyx6{Oj  
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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。 bS+by'Ea1W  
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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。 ':f
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脚本 Cr,UP8MO  
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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： aD~3C/?aW  
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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。 @L8(
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余下的脚本计算与屈光度有关的所有参数。 9tVA.:FOZ  
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分析 K YFumR  
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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。  ? {Lp  
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脚本代码 'Pudy\Ab  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. v?)-KtX|  
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Dim entity As T_ENTITY J 21D/#v  
Dim op As T_OPERATION nB
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Dim mat As T_MODELMATERIAL .N99=%[}h  
Dim A As Double w<*tbq  
Dim pupilDiam As Double wj/\!V!  
Dim eID As Long 8YAUy\  
Dim parID As Long c<j2wKz  
Dim count As Integer LqTyE  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double q"5iza__H  
Dim tlens As Double, nlens As Double I)AV  
Dim curv As Double, conic As Double #N%xr'H  
Dim ok As Long $ +h~VC  
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Sub Main ?k~(E`ZE3  
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    '用户输入对话框 MJJy mi'b  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Dx =ms^oN5  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ^zHBDRsb2F  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 wAxXK94#3  
        OKButton 40,91,90,21 f0fN1
 
        CancelButton 190,91,90,21 z!5^UD8"W  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 vBUx)l  
        TextBox 220,49,40,21,.TextBox2 'default: 4 .Y!*6I  
    End Dialog LQ"56PP<  
    Dim dlg As UserDialog uh3%}2'P  
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    ok = Dialog (dlg) _*1/4^  
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    If ok=0 Then    'cancel button was pressed 'D8WNZ8Q  
        Print "Execution cancelled." T9\wkb.  
        End IpmblC4  
    End If Qj?+R F6(  
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    'Assign accommodation and pupil diameter & use defaults if field left empty |jV>  
    If dlg.TextBox1 = "" Then A^_BK(EY  
        A = 0           'Default accommodation kJqgY|  
    Else u-3A6Q  
        A = CDbl(dlg.TextBox1) rIg1]q  
    End If ]'=]=o~4  
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    If dlg.TextBox2 = "" Then }3F8[Td.~N  
        pupilDiam = 4   'Default pupil diameter wp`a:QZ8N  
    Else |BnjT*_9  
        pupilDiam = CDbl(dlg.TextBox2) -Zd!0HNW1  
    End If ^ElUU?rX  
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    Print " " CN@bJo2  
    Print "Accommodation = " & A & " Diopters" V} Y %9V  
    Print "Pupil Diameter = " & pupilDiam & " mm" D)XF@z;  
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    ' Calculate new parameters with accommodation QWv+Ja  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness bB'iK4  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens %geiJ z  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens W}bed],l  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens -! Hn,93  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens -l<b|`s=w.  
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    tlens = 3.767 + 0.04*A                  'Lens thickness W"+*%x  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction tM]~^U  
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    'Adjust parameters to account for accommodation okJ+Yl.[?7  
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    '************************************************************************* XRCiv   
    'Aqueous thickness (Position of Lens) x?Doe`/6?  
    '************************************************************************* f/RzE  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 72R|zR  
    GetCustomElement eID, entity yB\}e'J^  
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    parID = FindFullName( "Geometry.Arizona Eye" ) 0gw0  
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    ' Delete any shift(s) in z 
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    count = 0 DZ -5A  
    While GetOperationCount(eID)>count X&fM36o7  
        GetOperation eID, count, op St9W{  
        If op.Type="ShiftZ" Then K>X#,lE-  
            DeleteOperation eID,count Fg<$;p  
            count=count-1 A#$oY{"2Y  
        End If ]3]I`e{  
        count=count+1 A ><  
    Wend ol7%$:S  
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    'Set new shift in w%R(*,r6  
    op.Type = "ShiftZ" A@xa$!4}  
    op.val1 = taq F7lhLly  
    op.parent = parID reJw&t}Q  
    AddOperation eID, op ^.)oQo SE  
    Print "Set aqueous humor thickness = " & taq-0.55 Bee`Pp2  
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    '************************************************************************* "C%<R  
    'Radius and conic constant of anterior lens 5H#f;L\k  
    '************************************************************************* NovF?kh2  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ,Bax0p  
    GetConic eID, entity, curv, conic =aZgq99  
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    SetConic eID, entity, 1/Rant, CCant _K["qm{X_  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant H<41H;m  
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    '************************************************************************* =vJ:R[Ilw  
    'Radius and conic constant of posterior lens Hy=';Ccn}  
    '************************************************************************* !m8MyZ}%  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) OP0KK^#  
    GetConic eID, entity, curv, conic 5r)ndW,aN  
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    SetConic eID, entity, 1/Rpost, CCpost tb36c<U-  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost c-1,((p  
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    '************************************************************************* 
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    'Lens thickness (Position of posterior lens surface) vOIK6-  
    '************************************************************************* sI\v}$(~  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) .kKU
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    ' Delete any z-shift(s) L~9Q7 6w  
    count = 0 2$ m#)*\  
    While GetOperationCount(eID)>count !YX$4_I  
        GetOperation eID, count, op Kz>bfq7  
        If op.Type="ShiftZ" Then ,5}%_  
            DeleteOperation eID,count A$d)xq-]K  
            count=count-1 ZYRZ$87jZ  
        End If ZcJa:  
        count=count+1 Lv;% z  
    Wend t<=Ru*p  
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    'Set new z-shift _v=S4A#tF  
    op.Type = "ShiftZ" /bm2v;  
    op.val1 = tlens 9O(vh(C  
    op.parent = parID 4-j3&
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    AddOperation eID, op HK}br!?  
    Print "Set lens thickness = " & tlens ].ZfT
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    '************************************************************************* RHO|g0  
    'Lens index of refraction 1M@OBfB8  
    '************************************************************************* M9[52D!{  
    eID = FindMaterial( "Lens" ) YA+jLy6ZL  
    GetModelMaterial eID, mat 8w4-Ud*$i  
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    mat.Nd = nlens bsClw  
    SetModelMaterial eID, mat Nk JOD3>U  
    Print "Set lens index of refraction = " & nlens `G/%U~  
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    '************************************************************************* CG#lpAs  
    'Pupil diameter AS1#_fC  
    '************************************************************************* GgT 5'e;N  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 1`6kc9f.  
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    'Adjust pupil diameter (trimming volume inner hole) K Eda6zZH  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" |ty?Ah,vb  
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    ' Adjust pupil location to just in front of the lens 2uSXC*Phz  
    parID = FindFullName( "Geometry.Arizona Eye" ) qb$&BZj]|  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) y  J|/^qs  
    count = 0 L<D<3g|4  
    While GetOperationCount(eID)>count p]jkfsCjN  
        GetOperation eID, count, op 0Y>5&  
        If op.Type="ShiftZ" Then 4*0C_F@RX  
            DeleteOperation eID,count r~[Bzw"c  
            count=count-1 lIhP\:;S&  
        End If WHF[l1  
        count=count+1 ()}(3>O-  
    Wend $Wy(Wtrx|  
    op.Type = "ShiftZ" 8_W=
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    op.val1 = taq-0.01 xF8U )j!  
    op.parent = parID k3PFCl~e  
    AddOperation eID, op !k3 eUBF  
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    Print "Set pupil diameter = " & pupilDiam H^3f!\MC;o  
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    'Update AZ Eye subassembly Description Q6 oM$qiM  
    eID = FindFullName( "Geometry.Arizona Eye" ) Tv[h2_+E  
    GetEntity eID, entity aRV.;S  
    entity.Description = "Accommodation = " & A & "D" G-6k[-@-v  
    SetEntity eID, entity }AW"2<@  
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    Update OH >#f6`[  
    Print "DONE!" 5FJ(x:k?z  
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End Sub 4j1$1C{  
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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： @?2ES@G+Ji  
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Accommodation = 4 Diopters _|Uv7>}J^  
Pupil Diameter = 4 mm tE8aL{<R  
Set aqueous humor thickness = 2.81 f&L3M)T  
Set anterior lens radius = 10.4 and conic constant = -2.375869 FoQy@GnM5  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 3<x1s2
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Set lens thickness = 3.927 ;7>k[?'e  
Set lens index of refraction = 1.42672 x%'5rnm|  
Set pupil diameter = 4 M!wa }  
DONE! v]GQb