[技术]Arizona眼睛模型 [复制链接]

简介 +uWDP.  
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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。 8zLY6@
  

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模型 fP tm0.r  
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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。 -LDCBc"  
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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. _LAS~x7,  
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光源 Q9d`z
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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。 }pk#!
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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。 Uie?9&3  
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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。 }?cGf-c  
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视网膜的散射 !zPG?q]3  
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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。 2j(h+?N7k  
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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。 vA$o~?a]/  
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脚本 Auy_K?he]  
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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： [Q\GxX.  
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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。 6"c1;P!4   
余下的脚本计算与屈光度有关的所有参数。
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分析 AtR?J"3E  
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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。 ^QuiH'  
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脚本代码 >
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. e]=!"nJ+  
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Dim entity As T_ENTITY +(uYwdcN  
Dim op As T_OPERATION )BfT7{WN  
Dim mat As T_MODELMATERIAL 3E f1bhi  
Dim A As Double y=Mq(c:'UN  
Dim pupilDiam As Double ZVeaTK4_ t  
Dim eID As Long 64-#}3zL  
Dim parID As Long 9h/>QLx  
Dim count As Integer x8
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Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double q1E:l!2al  
Dim tlens As Double, nlens As Double H _Va"yTO6  
Dim curv As Double, conic As Double o]IjK  
Dim ok As Long OMwsbp&  
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Sub Main bCZ gcN  
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    '用户输入对话框 RE.r4uOJg  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 #YDr%>
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        TextBox 220,21,40,21,.TextBox1 'default: 0 *m%]zj0bo  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 TO2c"7td  
        OKButton 40,91,90,21 ~2EHOO{  
        CancelButton 190,91,90,21 &C>/L;  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 DF6c|  
        TextBox 220,49,40,21,.TextBox2 'default: 4 OT^%3:
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    End Dialog $D31Q[p=+  
    Dim dlg As UserDialog fQLt=Lrp  
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    ok = Dialog (dlg) <o2r~E0r3  
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    If ok=0 Then    'cancel button was pressed iYnEwAoN;  
        Print "Execution cancelled." KJE[+R H+z  
        End ]pEV}@7  
    End If 3D9!M-  
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    'Assign accommodation and pupil diameter & use defaults if field left empty {brMqE>P#  
    If dlg.TextBox1 = "" Then 7u\*_mrv  
        A = 0           'Default accommodation ~)?  
    Else LJX-AO.4  
        A = CDbl(dlg.TextBox1) `si#aU  
    End If *&AfR8x_z  
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    If dlg.TextBox2 = "" Then /v095H@  
        pupilDiam = 4   'Default pupil diameter 4/X/>Y1  
    Else Nr2C@FU:0  
        pupilDiam = CDbl(dlg.TextBox2) :V)lbn\  
    End If E{HY!L[
 
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    Print " " xoB},Xl$D  
    Print "Accommodation = " & A & " Diopters" #S%Q*k<hw  
    Print "Pupil Diameter = " & pupilDiam & " mm" (wc03,K^  
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    ' Calculate new parameters with accommodation crO@?m1  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness _md=Q$9!m  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 4`#F^2r!  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens D71;&G]0  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens k7tYa;C  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens T^Ab!O  
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    tlens = 3.767 + 0.04*A                  'Lens thickness ,mPnQ?  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction )hwV`2>l  
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    'Adjust parameters to account for accommodation $ _8g8r}  
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    '************************************************************************* ~_9"
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    'Aqueous thickness (Position of Lens) 93[DAs  
    '************************************************************************* #6Xs.*b5C  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) P
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    GetCustomElement eID, entity HxK$4I`  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ]E3U J!
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    ' Delete any shift(s) in z 1Xy]D  
    count = 0 sqx`">R  
    While GetOperationCount(eID)>count 2?Ye*-  
        GetOperation eID, count, op 5>9Y|UU  
        If op.Type="ShiftZ" Then DN4#H`  
            DeleteOperation eID,count ,n2i@?NHZ  
            count=count-1 0;
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        End If dQy>Nmfy  
        count=count+1 66snC{gU  
    Wend s!/TU{8J  
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    'Set new shift in r%Rs0)$yj  
    op.Type = "ShiftZ" {|9}+ @5Q1  
    op.val1 = taq }~Q"s2  
    op.parent = parID y0v]N  
    AddOperation eID, op lC97_T  
    Print "Set aqueous humor thickness = " & taq-0.55 *cWmS\h|  
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    '************************************************************************* l2b{u GE  
    'Radius and conic constant of anterior lens PXP`ZLF  
    '************************************************************************* `n!viW|tB  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) [%HIbw J  
    GetConic eID, entity, curv, conic 7#;vG>]  
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    SetConic eID, entity, 1/Rant, CCant fbZibcQ%k  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant
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    '*************************************************************************
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    'Radius and conic constant of posterior lens b syq*  
    '************************************************************************* }:iBx  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 2k7bK6=nm  
    GetConic eID, entity, curv, conic _BnTv$.P  
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    SetConic eID, entity, 1/Rpost, CCpost YHxbDf dA  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost ]pTvMom$6  
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    '************************************************************************* S_J :&9L  
    'Lens thickness (Position of posterior lens surface) z?8~[h{i%  
    '************************************************************************* ScnY3&rc  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) f<[jwhCWV  
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    ' Delete any z-shift(s) OVoO6F]  
    count = 0 HgJb4Fi  
    While GetOperationCount(eID)>count !7H6i#g*  
        GetOperation eID, count, op O^{1RV3:,T  
        If op.Type="ShiftZ" Then V7CoZnz  
            DeleteOperation eID,count (VHND%7P  
            count=count-1 Uv?'m&_  
        End If x49!{}  
        count=count+1 "#^MUQ!a  
    Wend a,'Cyv">  
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    'Set new z-shift T)u4S[ &  
    op.Type = "ShiftZ" :x>T}C<Y  
    op.val1 = tlens {'3D1#SK  
    op.parent = parID kv|,b  
    AddOperation eID, op ESQ!@G/n  
    Print "Set lens thickness = " & tlens f%fa{  
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    '************************************************************************* 4~?2wvz G4  
    'Lens index of refraction )@QJ  
    '************************************************************************* 4-4?IwS  
    eID = FindMaterial( "Lens" ) ;'kI/(;;C  
    GetModelMaterial eID, mat kM*T$JqN  
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    mat.Nd = nlens dBEIMn@  
    SetModelMaterial eID, mat c cG['7  
    Print "Set lens index of refraction = " & nlens Zy$Lrr!  
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    '************************************************************************* ?A=b6Um  
    'Pupil diameter ;"7/@&M\m  
    '************************************************************************* 4_Rdp`x#J  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ~@c-*  
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    'Adjust pupil diameter (trimming volume inner hole) IlZu~B9c  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ;x[pM_  
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    ' Adjust pupil location to just in front of the lens X\2_;zwf  
    parID = FindFullName( "Geometry.Arizona Eye" ) ,7/ _T\d<  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) k&Jo"[i&WO  
    count = 0 tP'GNsq+m  
    While GetOperationCount(eID)>count >[K?fJ$+  
        GetOperation eID, count, op 2;(W-]V?  
        If op.Type="ShiftZ" Then ;w6s<a@Zh  
            DeleteOperation eID,count qe?Ggz3p.  
            count=count-1 mZoD033H  
        End If Z.jCera.  
        count=count+1 wa?+qiWnrl  
    Wend Z] {@H  
    op.Type = "ShiftZ" jb@\i@-  
    op.val1 = taq-0.01 vo;5f[>4i  
    op.parent = parID v
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    AddOperation eID, op sco uO$
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    Print "Set pupil diameter = " & pupilDiam Q_lu`F|  
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    'Update AZ Eye subassembly Description U>3 >Ex  
    eID = FindFullName( "Geometry.Arizona Eye" ) wixD\t59X  
    GetEntity eID, entity )1z4q`  
    entity.Description = "Accommodation = " & A & "D" -N^=@Yx)  
    SetEntity eID, entity [t}):}~F|  
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    Update >\\5"Sf  
    Print "DONE!" q!
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End Sub $MT}l  
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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： W:B}u\)C  
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Accommodation = 4 Diopters 32KR--mn%  
Pupil Diameter = 4 mm .CmL7 5  
Set aqueous humor thickness = 2.81 _W+Q3Jx-(  
Set anterior lens radius = 10.4 and conic constant = -2.375869 =tq7z =k  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 7,su f }=  
Set lens thickness = 3.927 o[{&!t  
Set lens index of refraction = 1.42672 /$*; >4=>f  
Set pupil diameter = 4 t'Htx1#Zc[  
DONE! &Q+]t"OA!