[技术]Arizona眼睛模型 [复制链接]

简介 k;bdzcMkQ  
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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。 sAG#M\A6  
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模型 utDjN"  
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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。 N @24)g?  
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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. gLyE,1Z}u  
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光源 =83FCq"  
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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。 k1
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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。 9J0JSy  
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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。 ?pF7g$>q  
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视网膜的散射 ah(lH5r  
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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。 MY[QYBkn}  
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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。 0"*!0s~  
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脚本 |@a.dgz,  
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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： 9HjtWQn  
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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。 l20fA-T _I  
余下的脚本计算与屈光度有关的所有参数。 zuq7 x7
 
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分析 VhWF(*  
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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。  tdl Y  
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脚本代码 /:YJ
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. mkR1iY  
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Dim entity As T_ENTITY XpFoSW#K  
Dim op As T_OPERATION Zi0B$3iOb  
Dim mat As T_MODELMATERIAL y2>XLELy  
Dim A As Double @213KmB.  
Dim pupilDiam As Double ~(BvIzzD  
Dim eID As Long z2Pnni7Ys  
Dim parID As Long UJqDZIvC  
Dim count As Integer 1qR[&=/  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double <rO0t9OH  
Dim tlens As Double, nlens As Double FXHcy:)}G  
Dim curv As Double, conic As Double 'pJ46"D@m  
Dim ok As Long TTJFF\$?  
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Sub Main jK[~dY
  
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    '用户输入对话框 E!~Ok  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 *@XJ7G[  
        TextBox 220,21,40,21,.TextBox1 'default: 0 DP(JsZ}  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 %[x oA)0!  
        OKButton 40,91,90,21 lHV&8fny  
        CancelButton 190,91,90,21 h\jV@g$  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 $yZ(c#L  
        TextBox 220,49,40,21,.TextBox2 'default: 4 w4:  
    End Dialog [>B`"nyNQ  
    Dim dlg As UserDialog jkPye{j  
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    ok = Dialog (dlg) BD)5br].  
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    If ok=0 Then    'cancel button was pressed 986y\9Zu  
        Print "Execution cancelled." 8y<NT"  
        End @_gCGI>Q  
    End If our$Ka31  
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    'Assign accommodation and pupil diameter & use defaults if field left empty '8auj  
    If dlg.TextBox1 = "" Then ^yO+-A2zC  
        A = 0           'Default accommodation i; 8""A  
    Else y+ZRh?2  
        A = CDbl(dlg.TextBox1) Ft7{P.g  
    End If b'D|p/)m0S  
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    If dlg.TextBox2 = "" Then B,@<60u  
        pupilDiam = 4   'Default pupil diameter ewo
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    Else 1eg/<4]hA  
        pupilDiam = CDbl(dlg.TextBox2) `
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    End If nLA8Hy"8z  
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    Print " " 6;LM1 _  
    Print "Accommodation = " & A & " Diopters" D{Zjo)&tF'  
    Print "Pupil Diameter = " & pupilDiam & " mm" 7e{w)m:A  
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    ' Calculate new parameters with accommodation Dr;-2$Kt/&  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness E>/kNl  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens H5L~[\ 5t  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens QKj-"y[  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Ig9gGI,  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens //SH=>w2
 
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    tlens = 3.767 + 0.04*A                  'Lens thickness px@:t}  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ZT UaF4k j  
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    'Adjust parameters to account for accommodation uR|?5DK  
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    '************************************************************************* !xU1[,9  
    'Aqueous thickness (Position of Lens) hAPWEh^  
    '************************************************************************* <<43'N+  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) \DP*?D_}?  
    GetCustomElement eID, entity Ca: jN0  
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    parID = FindFullName( "Geometry.Arizona Eye" ) /H_,1Fu|  
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    ' Delete any shift(s) in z bITc9Hqc  
    count = 0 6$1d
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    While GetOperationCount(eID)>count k{*IR  
        GetOperation eID, count, op 0KW@j>=jK  
        If op.Type="ShiftZ" Then WaU+ZgDrG  
            DeleteOperation eID,count 8PQn=k9  
            count=count-1 ]9xuLJ)  
        End If 'A0.(a5  
        count=count+1 7j9:s>D  
    Wend ()< E?D=  
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    'Set new shift in }b9"&io  
    op.Type = "ShiftZ" UL81x72O  
    op.val1 = taq _l?InNv  
    op.parent = parID s>=DfE-;"  
    AddOperation eID, op &RRHmJI:  
    Print "Set aqueous humor thickness = " & taq-0.55 9:|z^r  
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    '************************************************************************* =0te.io)3O  
    'Radius and conic constant of anterior lens QXXB>gOY5  
    '************************************************************************* {1RI!#[\  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) {K\l3_=5qb  
    GetConic eID, entity, curv, conic C- Aiv@@<=  
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    SetConic eID, entity, 1/Rant, CCant _[zZm*  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant z6~cm6j  
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    '************************************************************************* `1|#Za~e  
    'Radius and conic constant of posterior lens !PQ%h/ix  
    '************************************************************************* .\r=1HZ3  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) a;=)`  
    GetConic eID, entity, curv, conic "N"$B~W*  
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    SetConic eID, entity, 1/Rpost, CCpost {!? @u?M  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost x-wIgo+  
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    '************************************************************************* :}QBrd  
    'Lens thickness (Position of posterior lens surface) Tr}z&efY  
    '************************************************************************* =oN(1k^  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) &`#k1t'  
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    ' Delete any z-shift(s) X9W'.s.[Q  
    count = 0 UKYQ @m  
    While GetOperationCount(eID)>count gN2$;hb?  
        GetOperation eID, count, op ~%SmH[i  
        If op.Type="ShiftZ" Then {M`yYeo  
            DeleteOperation eID,count 'q158x  
            count=count-1 cT2&nZ  
        End If H
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        count=count+1 j_` [Z  
    Wend []i/\0C^  
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    'Set new z-shift s)Gnj;  
    op.Type = "ShiftZ" N$\'X<{  
    op.val1 = tlens j7(sYo@x7  
    op.parent = parID !n;0%"(FH  
    AddOperation eID, op rF9|xgFK  
    Print "Set lens thickness = " & tlens MQs!+Z"m>  
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    '************************************************************************* Ban@$uf  
    'Lens index of refraction cB$OkaG#  
    '************************************************************************* $w,?%i97  
    eID = FindMaterial( "Lens" ) -^1}J  
    GetModelMaterial eID, mat cyM9[X4rC  
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    mat.Nd = nlens @uh^)6i]/  
    SetModelMaterial eID, mat to2;. ~X  
    Print "Set lens index of refraction = " & nlens |PGF g0li  
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    '************************************************************************* \a<7DTV  
    'Pupil diameter `,lm:x+(0  
    '************************************************************************* [ B{F(~O  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) mLEJt,X  
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    'Adjust pupil diameter (trimming volume inner hole) C bWz;
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" ;(&$Iw9X  
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    ' Adjust pupil location to just in front of the lens csh@C ckC8  
    parID = FindFullName( "Geometry.Arizona Eye" ) 1X8P v*,  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" )  lu_kir~  
    count = 0 u+5&^"72,  
    While GetOperationCount(eID)>count +9^V9]{Vo  
        GetOperation eID, count, op Z\lJE>1  
        If op.Type="ShiftZ" Then _GhP{C$  
            DeleteOperation eID,count ~Q+E""  
            count=count-1 0W_olnZ  
        End If PO*;V<^  
        count=count+1 CF,-l B  
    Wend r\PO?1  
    op.Type = "ShiftZ" (DLk+N4UHA  
    op.val1 = taq-0.01 JXx[e  
    op.parent = parID g~7x+cu0  
    AddOperation eID, op <?2g\+{s9  
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    Print "Set pupil diameter = " & pupilDiam xK*G'3Ge  
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    'Update AZ Eye subassembly Description e/7rr~"|  
    eID = FindFullName( "Geometry.Arizona Eye" ) ugu|?z*dI  
    GetEntity eID, entity XRl!~Y|  
    entity.Description = "Accommodation = " & A & "D" `4Swd
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    SetEntity eID, entity R|@?6<  
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    Update WMw|lV r  
    Print "DONE!" (]@yDb4  
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End Sub gzMp&J  
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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： euMJ c  
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Accommodation = 4 Diopters 3(oB[9]s  
Pupil Diameter = 4 mm |j2$G~B6  
Set aqueous humor thickness = 2.81 E%b*MU  
Set anterior lens radius = 10.4 and conic constant = -2.375869 nk*T x  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 ]lqe,>  
Set lens thickness = 3.927 ;f!}vo<;  
Set lens index of refraction = 1.42672 ,qK'!  
Set pupil diameter = 4 p!o?2Lbiw  
DONE! gcA,u)z}R