[技术]Arizona眼睛模型 [复制链接]

简介 ;8XRs?xyd  
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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。 0sU*3r?  
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模型 9s_^?
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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。 2? yo  
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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. Dfzj/spFV  
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光源 +@^);b6  
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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。 MhCU; !  
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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。 uarfH]T{  
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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。 -_Z4)"k  
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视网膜的散射 8 5ET$YV  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 \\\8{jq  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 Jf?6y~X>Y  
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脚本 Godrz*"  
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内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： gm)Uyr$  
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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。 GqRXNs!  
余下的脚本计算与屈光度有关的所有参数。 A`Dx]y  
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分析 L_Gw:"-+Q  
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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。 Oq.ss!/z  
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脚本代码 e9[72V  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. u5A?; a  
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Dim entity As T_ENTITY ;B=aK"\  
Dim op As T_OPERATION DO80HS3ZD  
Dim mat As T_MODELMATERIAL * HKu%g  
Dim A As Double l{Df{1b.  
Dim pupilDiam As Double b&F9<XLqq  
Dim eID As Long RJ3oI+gI  
Dim parID As Long ;`#R9
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Dim count As Integer A!bG2{r  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double /dY
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Dim tlens As Double, nlens As Double VdK%m`;2  
Dim curv As Double, conic As Double 3>1^$0iq  
Dim ok As Long W\kli';jyC  
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Sub Main xW`y7Q}p  
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    '用户输入对话框 D|9+:Y  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Bx#i?=*W  
        TextBox 220,21,40,21,.TextBox1 'default: 0 DRQx5fgL  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 N;|^C{uz  
        OKButton 40,91,90,21 ~'_cBJ 'XD  
        CancelButton 190,91,90,21 S\TXx79PhC  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 en< $.aY  
        TextBox 220,49,40,21,.TextBox2 'default: 4 06pvI}  
    End Dialog bGWfMu=n  
    Dim dlg As UserDialog l\s!A&L  

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    ok = Dialog (dlg) U7s$';y"%  
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    If ok=0 Then    'cancel button was pressed _!',%+  
        Print "Execution cancelled." -)}s{[]d6m  
        End =hKAwk/^  
    End If Z0Z6aZeb  
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    'Assign accommodation and pupil diameter & use defaults if field left empty y>a?<*Y+e  
    If dlg.TextBox1 = "" Then &-ropY  
        A = 0           'Default accommodation 9wWBE<}>u  
    Else "@UQSf,  
        A = CDbl(dlg.TextBox1) 3%Y:+%VE  
    End If &$ h~Q  
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    If dlg.TextBox2 = "" Then
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        pupilDiam = 4   'Default pupil diameter Uq .6h  
    Else )Z/"P\qo  
        pupilDiam = CDbl(dlg.TextBox2) "bo0O7InOV  
    End If P"w\hF  
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    Print " " >pU9}2fpT  
    Print "Accommodation = " & A & " Diopters" Op'a=4x]  
    Print "Pupil Diameter = " & pupilDiam & " mm" [%P#ieD4  
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    ' Calculate new parameters with accommodation ^LMgOA(7  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness cl~Yx4  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens ote,`h  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens (GSP3KKo*G  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens x)::^'74  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens M5^Y W#e  
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    tlens = 3.767 + 0.04*A                  'Lens thickness W7>2&$
  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Zl
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    'Adjust parameters to account for accommodation HxG8'G  
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    '************************************************************************* YT\@fgBt  
    'Aqueous thickness (Position of Lens) ":Wq<Z'  
    '************************************************************************* bNea5u##  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) Y?0/f[Ax,y  
    GetCustomElement eID, entity JVE\{ e)  
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    parID = FindFullName( "Geometry.Arizona Eye" ) -#|D>  
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    ' Delete any shift(s) in z HK@ij,px  
    count = 0 @]=40Yj~w  
    While GetOperationCount(eID)>count }s}g}t8v-  
        GetOperation eID, count, op [?!I*=*b  
        If op.Type="ShiftZ" Then 1+x" 5<(W  
            DeleteOperation eID,count q-F K=r 5  
            count=count-1 pO`KtagL  
        End If 8|a./%gixs  
        count=count+1 (`tRJWbdz  
    Wend ScPVjqG2{  
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    'Set new shift in 2{OR#v~  
    op.Type = "ShiftZ" %Y^J''  
    op.val1 = taq [{x}# oRSE  
    op.parent = parID AYts &+  
    AddOperation eID, op J+6zV m  
    Print "Set aqueous humor thickness = " & taq-0.55 Rr)+M3'  
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    '************************************************************************* 4U}qrN~=  
    'Radius and conic constant of anterior lens 3N7H7(IR  
    '************************************************************************* TktH28tK  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) K+B978XD  
    GetConic eID, entity, curv, conic UiFH*HT  
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    SetConic eID, entity, 1/Rant, CCant u^80NR  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant G-aR%]7$g  
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    '************************************************************************* Zi!Ta"}8  
    'Radius and conic constant of posterior lens $NXP)Lic)  
    '************************************************************************* F@w; .e!  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) xs$$fPAQ  
    GetConic eID, entity, curv, conic iGN\ >m}  
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    SetConic eID, entity, 1/Rpost, CCpost }lJ;|kx$  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost bzgC+yT  
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    '************************************************************************* }U_ '7_JT  
    'Lens thickness (Position of posterior lens surface) "t@p9>  
    '************************************************************************* 8%?y)K^ D  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) [Kgb#L'{  
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    ' Delete any z-shift(s) &p0e)o~Ux  
    count = 0 UO/sv2CN  
    While GetOperationCount(eID)>count VtreOJ+  
        GetOperation eID, count, op wp[Ug2;G  
        If op.Type="ShiftZ" Then ,"(L2+Yp  
            DeleteOperation eID,count @f!X%)\;x  
            count=count-1 okNo-\Dh!  
        End If sp9gz~Kq
 
        count=count+1 d0cL9&~qW  
    Wend NFK
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    'Set new z-shift 1<@SMcj>  
    op.Type = "ShiftZ" I.2J-pu}  
    op.val1 = tlens x&}]8S)  
    op.parent = parID 3a/n/_D  
    AddOperation eID, op r~w.J+W  
    Print "Set lens thickness = " & tlens '%)R}wgV  
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    '************************************************************************* 4zug9kFK  
    'Lens index of refraction 9>""x
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    '************************************************************************* Yo-}uTkw  
    eID = FindMaterial( "Lens" ) Cs,H#L  
    GetModelMaterial eID, mat )G? qX.D  
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    mat.Nd = nlens vW63j't_  
    SetModelMaterial eID, mat IgT`on3Y  
    Print "Set lens index of refraction = " & nlens
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    '************************************************************************* +/:tap|V  
    'Pupil diameter ?GhyVXS y.  
    '************************************************************************* 5En
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 1v o)]ff  
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    'Adjust pupil diameter (trimming volume inner hole) *Ak.KBg  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" PT"}2sR)  

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    ' Adjust pupil location to just in front of the lens jYsAL=oh,*  
    parID = FindFullName( "Geometry.Arizona Eye" ) R[WiW RfD  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) }`"`VLh  
    count = 0 4 1_gak;  
    While GetOperationCount(eID)>count jm_-f  
        GetOperation eID, count, op 7>JYwU{  
        If op.Type="ShiftZ" Then B.z$0=b  
            DeleteOperation eID,count +)]YvZ6%[,  
            count=count-1 p!.~hw9  
        End If g(7-3q8eq  
        count=count+1 @=J|%NO  
    Wend |HazM9=  
    op.Type = "ShiftZ" @Mk`Tl  
    op.val1 = taq-0.01 ]B8 A  
    op.parent = parID q76POytV|  
    AddOperation eID, op }
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    Print "Set pupil diameter = " & pupilDiam h}b:-a  
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    'Update AZ Eye subassembly Description O*yxOb*  
    eID = FindFullName( "Geometry.Arizona Eye" ) Iv`IJQH>  
    GetEntity eID, entity w~'xZ?  
    entity.Description = "Accommodation = " & A & "D" *Cy54Z#  
    SetEntity eID, entity u\R?(G&  
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    Update UA[`{rf  
    Print "DONE!" dZM^?rq  
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End Sub qsj{0Go  
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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： qTO6I5u  
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Accommodation = 4 Diopters ul{x|R  
Pupil Diameter = 4 mm _vQ52H,  
Set aqueous humor thickness = 2.81 ZbnAAbfKH  
Set anterior lens radius = 10.4 and conic constant = -2.375869 qY_qS=H^  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 J0G@]H  
Set lens thickness = 3.927 TS<d?:  
Set lens index of refraction = 1.42672 j0=6B  
Set pupil diameter = 4 $-4](br|  
DONE! +X?ErQm