[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。 oRbWqN`F.  
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模型 "r6qFxY  
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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。 wiI@DJ>E  
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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. KF7w{A){  
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光源 dg|+?M^9`  
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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。 P"7` :a  
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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。 3Y P! B=  
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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。 S:!5|o|  
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视网膜的散射 m !:F/?B  
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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。 UW":&`i  
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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。 l4kqz.Z-g  
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脚本 !
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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： 7_Vd%<:  
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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。 ~H''RzN  
余下的脚本计算与屈光度有关的所有参数。 z .lb(xQ  
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分析 `LFT"qnp  
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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。 ^/2O_C  
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脚本代码 2;:]Q.g  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. qUe2(/TQu  
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Dim entity As T_ENTITY jhG6,;1zMI  
Dim op As T_OPERATION %_]O|(  
Dim mat As T_MODELMATERIAL -XECYwTh  
Dim A As Double [Qkj}  
Dim pupilDiam As Double l7ES*==&@0  
Dim eID As Long Uwiy@T Z  
Dim parID As Long %Y`)ZKh  
Dim count As Integer ,vi6<C\  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double :@~3wD[y  
Dim tlens As Double, nlens As Double @6jKjI  
Dim curv As Double, conic As Double mznE Cy  
Dim ok As Long 9MRe?  
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Sub Main =a
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    '用户输入对话框 1iY?t  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ohXbA9&(x  
        TextBox 220,21,40,21,.TextBox1 'default: 0 b4^a zY  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 #z}IW(u<  
        OKButton 40,91,90,21 KG5B6Om5'  
        CancelButton 190,91,90,21 YcaLc_pUx  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 P`hg*"<V  
        TextBox 220,49,40,21,.TextBox2 'default: 4 nNM)rW  
    End Dialog 9LEU
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    Dim dlg As UserDialog =>C3IR/  
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    ok = Dialog (dlg) wd:SBU~f5*  
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    If ok=0 Then    'cancel button was pressed h8SK8sK<  
        Print "Execution cancelled." \4q1<j  
        End n@e|PWu  
    End If 3Z)vJC9'  
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    'Assign accommodation and pupil diameter & use defaults if field left empty [VB\T|$  
    If dlg.TextBox1 = "" Then WAw} ?&k  
        A = 0           'Default accommodation `WU"*HqW  
    Else  b|h`v  
        A = CDbl(dlg.TextBox1) rFv=j:8  
    End If iGeuO[^  
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    If dlg.TextBox2 = "" Then ^nL_*+V`f  
        pupilDiam = 4   'Default pupil diameter r+l3J>:K  
    Else 2ap0/l[  
        pupilDiam = CDbl(dlg.TextBox2) /Big^^u  
    End If m>?{flO  
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    Print " " ?<$DQ%bf  
    Print "Accommodation = " & A & " Diopters" zwX1&rN  
    Print "Pupil Diameter = " & pupilDiam & " mm" *$7c||J7  
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    ' Calculate new parameters with accommodation UG
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    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness ~4tu*\P  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens of:xj$dQ_  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens O7RW*V:G@  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 0l
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 1vBXO bk  
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    tlens = 3.767 + 0.04*A                  'Lens thickness '`Z5.<n7p  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Dos`lh  
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    'Adjust parameters to account for accommodation 5zF7yvS.w  
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    '************************************************************************* Hi<5jl  
    'Aqueous thickness (Position of Lens) qMe$Qr8  
    '************************************************************************* p9)'nU'\t  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) W`-AN}C#  
    GetCustomElement eID, entity <J QvuC  
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    parID = FindFullName( "Geometry.Arizona Eye" ) y\&`A:^[ A  
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    ' Delete any shift(s) in z @
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    count = 0 Ie~#k[X  
    While GetOperationCount(eID)>count ^i^/d#  
        GetOperation eID, count, op rBZ0(XSZQ  
        If op.Type="ShiftZ" Then RscU=oaKi  
            DeleteOperation eID,count bgjo_!J+Pp  
            count=count-1 64>o3Hb2  
        End If ~sSlfQWMzy  
        count=count+1 jdGoPa\  
    Wend /t083  
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    'Set new shift in {(#>%f+|C  
    op.Type = "ShiftZ" 4cni_m]  
    op.val1 = taq Xj&fWuA  
    op.parent = parID _kb $S  
    AddOperation eID, op
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    Print "Set aqueous humor thickness = " & taq-0.55 m]$!wp  
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    '************************************************************************* >?q()>l  
    'Radius and conic constant of anterior lens mh"&KX86W  
    '************************************************************************* 9BPucXK  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) d3# >\QCD9  
    GetConic eID, entity, curv, conic S3u>a\  
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    SetConic eID, entity, 1/Rant, CCant brGUK PB  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 8-c1q*q)  
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    '************************************************************************* I_
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    'Radius and conic constant of posterior lens #]'#\d#i  
    '************************************************************************* vl<W`)'  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) |>(;gr/5(  
    GetConic eID, entity, curv, conic t3.;W/0_  
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    SetConic eID, entity, 1/Rpost, CCpost cbD&tsF  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost gf^"sfNk  
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    '************************************************************************* ON|Bpt2Qp  
    'Lens thickness (Position of posterior lens surface) ^9 gFW $]  
    '************************************************************************* Rw\ LVRd
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) eDR4c%  
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    ' Delete any z-shift(s) <)L'h  
    count = 0 ][1*.7-  
    While GetOperationCount(eID)>count sG`:mc~0  
        GetOperation eID, count, op u;m[,  
        If op.Type="ShiftZ" Then 2B{~"<  
            DeleteOperation eID,count FOxMt;|M  
            count=count-1 KPIc?|o/6  
        End If wiXdb[[#  
        count=count+1 vkWh2z  
    Wend T> cvV  
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    'Set new z-shift 2?hc94  
    op.Type = "ShiftZ" :gMcl"t--  
    op.val1 = tlens 48JD >=@7  
    op.parent = parID `x2Q:&.H`  
    AddOperation eID, op g/&`NlD  
    Print "Set lens thickness = " & tlens n$n)!XL/  
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    '************************************************************************* SnsOuC5Ah  
    'Lens index of refraction vs-%J6}G  
    '************************************************************************* Z?yMy zT  
    eID = FindMaterial( "Lens" ) $gU6=vN1#  
    GetModelMaterial eID, mat #;59THdtPk  
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    mat.Nd = nlens kXGJZ$  
    SetModelMaterial eID, mat / E~)xgPM<  
    Print "Set lens index of refraction = " & nlens ^sR]w]cz.  
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    '************************************************************************* EY=`/~|c  
    'Pupil diameter spIkXEK  
    '************************************************************************* 9~8 A>  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) z DDvXz  
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    'Adjust pupil diameter (trimming volume inner hole) :r%Hsur(  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" $xRZU9+  
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    ' Adjust pupil location to just in front of the lens Wy{xTLXk2  
    parID = FindFullName( "Geometry.Arizona Eye" ) 0F
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) $e66jV  
    count = 0 Y0`@$d&n  
    While GetOperationCount(eID)>count g.![>?2$8  
        GetOperation eID, count, op d4OWnPHv&}  
        If op.Type="ShiftZ" Then =\;yxl
 
            DeleteOperation eID,count w E^6DNh  
            count=count-1 $^|I?5xD  
        End If y{CyjYpz^  
        count=count+1 H'N$Vv2q  
    Wend TX7B(JZD  
    op.Type = "ShiftZ" NjT#p8d X  
    op.val1 = taq-0.01 DA'A-C2  
    op.parent = parID N|cWTbi  
    AddOperation eID, op KUs\7Sb  
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    Print "Set pupil diameter = " & pupilDiam  wfr+-  
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    'Update AZ Eye subassembly Description r83chR9  
    eID = FindFullName( "Geometry.Arizona Eye" ) So &c\Ff  
    GetEntity eID, entity a%f?OsY  
    entity.Description = "Accommodation = " & A & "D" ?@W=bJ8{  
    SetEntity eID, entity NPjh2 AJm  
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    Update -oGJPl{r  
    Print "DONE!" 2p3ep,  
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End Sub dxm_AUM  
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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： ;DWtCtD  
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Accommodation = 4 Diopters _y~H#r9:  
Pupil Diameter = 4 mm bJ8~/
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Set aqueous humor thickness = 2.81 v]*(Wd~|  
Set anterior lens radius = 10.4 and conic constant = -2.375869 MZ_+do
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Set posterior lens radius = -4.424557 and conic constant = -3.081019 RfPRCIo  
Set lens thickness = 3.927 >patv  
Set lens index of refraction = 1.42672 d\nBc6  
Set pupil diameter = 4 !6:q#B*  
DONE! 2Z]<MiAxD