[分享]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。 $,xnU.n  
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模型 \D>$aLO*?  
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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。 "U.^lkN  
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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. K/ &?VIi`z  
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光源 B*htN  
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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。 s] /tYJYl  
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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。 B12$I:x`  
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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。 C@N1ljXJT  
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视网膜的散射 :a:[.  
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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。
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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。 T^Ab!O  

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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： [nxE)D  
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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。 X5YiFLH>y\  
余下的脚本计算与屈光度有关的所有参数。 d@mo!zu  
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分析 +Taa!hfys  
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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。 KCe13!  
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脚本代码 :5GZ\Z8F  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. N__H*yP  
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Dim entity As T_ENTITY 7dihVvL $  
Dim op As T_OPERATION \EbbkN:D  
Dim mat As T_MODELMATERIAL F2(q>#<_  
Dim A As Double ]IJRnVp%  
Dim pupilDiam As Double x0a.!  
Dim eID As Long r%Rs0)$yj  
Dim parID As Long {|9}+ @5Q1  
Dim count As Integer }4co)B"  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double y0v]N  
Dim tlens As Double, nlens As Double lC97_T  
Dim curv As Double, conic As Double *cWmS\h|  
Dim ok As Long /EwGW  
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Sub Main j:5%ppIY  
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    '用户输入对话框 [%HIbw J  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 7#;vG>]  
        TextBox 220,21,40,21,.TextBox1 'default: 0 ~;-9X|
 
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 O`FqD{@V  
        OKButton 40,91,90,21 $#o1MX  
        CancelButton 190,91,90,21 _i}wK?n  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 jW*1E*"  
        TextBox 220,49,40,21,.TextBox2 'default: 4 eX&Gw{U-f  
    End Dialog g1DmV,W-Q  
    Dim dlg As UserDialog m$>iS@R
 
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    ok = Dialog (dlg) 8U~.\`H-PT  
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    If ok=0 Then    'cancel button was pressed ~Y5l+EF#  
        Print "Execution cancelled." x:K?\<  
        End BpAB5=M0  
    End If Z\X'd_1!  
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    'Assign accommodation and pupil diameter & use defaults if field left empty gLj?Ys  
    If dlg.TextBox1 = "" Then %@&a7JOL  
        A = 0           'Default accommodation $%2_{m_K:p  
    Else s #:%x#  
        A = CDbl(dlg.TextBox1) t[.W$1=  
    End If k/Mp6<?C:  
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    If dlg.TextBox2 = "" Then g+q@i{Yn  
        pupilDiam = 4   'Default pupil diameter .I?@o8'x  
    Else A,i()R'I  
        pupilDiam = CDbl(dlg.TextBox2) ^.X[)U  
    End If U/MFhD(06  
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    Print " " 5?u[XAE  
    Print "Accommodation = " & A & " Diopters" 6=|
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    Print "Pupil Diameter = " & pupilDiam & " mm" vg%QXaM  
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    ' Calculate new parameters with accommodation <SXZx9A!  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness >POO-8Q  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens .e[Tu|qo  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens D\L!F6taS  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens I{.HO<$7D}  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens H;vZm[\0N-  
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    tlens = 3.767 + 0.04*A                  'Lens thickness =v2%Vs\7k  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction MB$a82bY  
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    'Adjust parameters to account for accommodation 2PC5^Ni/9@  
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    '************************************************************************* 4^Qi2[w  
    'Aqueous thickness (Position of Lens)
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    '************************************************************************* n`5WXpz4;  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) g,
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    GetCustomElement eID, entity U~is-+Uq  
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    parID = FindFullName( "Geometry.Arizona Eye" ) wz#[:2  
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    ' Delete any shift(s) in z 1t~({Pl<>  
    count = 0 tW6#e(^l6  
    While GetOperationCount(eID)>count +mWjBY  
        GetOperation eID, count, op 4 eh=f!(+  
        If op.Type="ShiftZ" Then T&}Ye\%  
            DeleteOperation eID,count ?vbDB4  
            count=count-1 ofCVbn  
        End If  ]6~k4  
        count=count+1 OhWC}s  
    Wend iz x[  
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    'Set new shift in B3b,F
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    op.Type = "ShiftZ" #tz8{o?ebN  
    op.val1 = taq qzdaN5  
    op.parent = parID fGO*%)  
    AddOperation eID, op E`E'<"{Yd  
    Print "Set aqueous humor thickness = " & taq-0.55 _Xh=&(/8@  
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    '************************************************************************* gduxA/aT  
    'Radius and conic constant of anterior lens ,VG9)K1K  
    '************************************************************************* HYIRcY  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 9eSRCLhgD  
    GetConic eID, entity, curv, conic *,jqE9:O  
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    SetConic eID, entity, 1/Rant, CCant y9 uVCR
 
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 8&Wx@QI  
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    '************************************************************************* Vu|dV\N0*  
    'Radius and conic constant of posterior lens ABiC9[Q0  
    '************************************************************************* b+$o4l/x  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) kgc.8  
    GetConic eID, entity, curv, conic wO.B~`y  
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    SetConic eID, entity, 1/Rpost, CCpost 03
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    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost WB;
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    '*************************************************************************
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    'Lens thickness (Position of posterior lens surface) E3tj/4:L  
    '************************************************************************* <j"O%y.  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) TAAR'Jz S  
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    ' Delete any z-shift(s) ORtg>az\%  
    count = 0 ?1DUNZ6  
    While GetOperationCount(eID)>count GU#Q}L2  
        GetOperation eID, count, op [J:zE&aj
  
        If op.Type="ShiftZ" Then wy\o*P9mG)  
            DeleteOperation eID,count CRd_}  
            count=count-1 B%(K0`G#X  
        End If }!knU3J  
        count=count+1 _DrnL}9I7  
    Wend B{4"$Mi  
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    'Set new z-shift r'PE5xqF  
    op.Type = "ShiftZ" p}r yKW\cJ  
    op.val1 = tlens XWf7"]%SX  
    op.parent = parID ZU^Q1}</5  
    AddOperation eID, op !xJFr6G~8  
    Print "Set lens thickness = " & tlens
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    '************************************************************************* .Wh6(LDY(  
    'Lens index of refraction c}8 -/P=  
    '************************************************************************* {'&8`d  
    eID = FindMaterial( "Lens" ) \|Y{jG<cu  
    GetModelMaterial eID, mat mR6E]TuM  
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    mat.Nd = nlens 8}J(c=4Gk  
    SetModelMaterial eID, mat Ta,u-!/I  
    Print "Set lens index of refraction = " & nlens ~|qXtds$  
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    '************************************************************************* k~ZBJ+ 94  
    'Pupil diameter Hc"N& %X[  
    '************************************************************************* [I_BCf  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 6J]~A0vsi}  
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    'Adjust pupil diameter (trimming volume inner hole) ,&4zKm  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 8[f8k3g  
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    ' Adjust pupil location to just in front of the lens kS[Dy$AB/2  
    parID = FindFullName( "Geometry.Arizona Eye" ) w# xncH:1  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) !+%Az*ik  
    count = 0 c;nx59w]q  
    While GetOperationCount(eID)>count nJW_a&'  
        GetOperation eID, count, op r$Yh)rp
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        If op.Type="ShiftZ" Then m*OLoZVy  
            DeleteOperation eID,count '=-s1c@^  
            count=count-1 $)4GCP  
        End If qW+=g]x\  
        count=count+1 ;}$Z 80  
    Wend P~n8EO1r  
    op.Type = "ShiftZ" 6j?FRs  
    op.val1 = taq-0.01 r=xTs,xx  
    op.parent = parID _95- -\  
    AddOperation eID, op N,h1$)\B#  
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    Print "Set pupil diameter = " & pupilDiam qAnA=/k`  
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    'Update AZ Eye subassembly Description (ej:_w1  
    eID = FindFullName( "Geometry.Arizona Eye" ) d%S=$}o  
    GetEntity eID, entity <=#lRZW[z  
    entity.Description = "Accommodation = " & A & "D" 7AS.)Q#=x  
    SetEntity eID, entity Xv`2hf  
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    Update hg$qbeUl  
    Print "DONE!" s@.`"TF.7  
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End Sub A%.J%[MVz  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： CM+F7#T?n  
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Accommodation = 4 Diopters GMVC&^  
Pupil Diameter = 4 mm ey'pm\Z  
Set aqueous humor thickness = 2.81 tn(?nQN3  
Set anterior lens radius = 10.4 and conic constant = -2.375869 Tb5$  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 8<E!rn-  
Set lens thickness = 3.927 GlXA-p<  
Set lens index of refraction = 1.42672 $]Q*E4(kV9  
Set pupil diameter = 4 BG(R=, 7  
DONE! UrD=|-r`  
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