[技术]Arizona眼睛模型 [复制链接]

简介 IooAXwOF  
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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。 *ea%KE":  
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模型 I!IWmU6FN  
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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。 l{U-$}  
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在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd.
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光源 }Dk*Hs^E  
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多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 V=!tZ[4z$h  
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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。 hL:n9G  
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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。 Q v/}WnBk  
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视网膜的散射 GC(:}e|  
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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。 -)%l{@Mr  
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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。 qsnZ?hXPp  
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脚本 1#H=<iJ  
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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： JTuU}nm+  
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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。 @y,pfWh`  
余下的脚本计算与屈光度有关的所有参数。 $ZSjq  
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分析 >3R)&N  
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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。 0Da9,&D  
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脚本代码 z:B4  
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. @ i$jyc  
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Dim entity As T_ENTITY i v7^!  
Dim op As T_OPERATION qV^Z@N+,  
Dim mat As T_MODELMATERIAL 'l,ym~R  
Dim A As Double 906b=  
Dim pupilDiam As Double nCF1i2*6|"  
Dim eID As Long tOx)t$ix  
Dim parID As Long nM*-Dy3ou  
Dim count As Integer K&2{k+w  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double J[6`$$l0  
Dim tlens As Double, nlens As Double NRU&GCVwu  
Dim curv As Double, conic As Double JQCQpn/  
Dim ok As Long yu ~Rk  
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Sub Main }GV5':W@WG  
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    '用户输入对话框 WP/?(%#Y  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Ae,P&(  
        TextBox 220,21,40,21,.TextBox1 'default: 0 EqW/Wxv7b  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 '!8'Xo@Go3  
        OKButton 40,91,90,21 [ +w=  
        CancelButton 190,91,90,21 < {1'cx  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 0Z.bd=H  
        TextBox 220,49,40,21,.TextBox2 'default: 4 : b9X?%L~  
    End Dialog t= =+SHGP  
    Dim dlg As UserDialog A.0eeX{  
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    ok = Dialog (dlg) s,&tD WU  
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    If ok=0 Then    'cancel button was pressed HV_5 +  
        Print "Execution cancelled." 8UY[$lc  
        End A
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    End If AUZ^XiK  
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    'Assign accommodation and pupil diameter & use defaults if field left empty b#ih=qE  
    If dlg.TextBox1 = "" Then ;- ~}g7$  
        A = 0           'Default accommodation vU
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    Else h+,Eu7\88  
        A = CDbl(dlg.TextBox1) *^|.bBG  
    End If KmUH([#  
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    If dlg.TextBox2 = "" Then Y 6B7qp  
        pupilDiam = 4   'Default pupil diameter ;3~+M:{2  
    Else /r
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        pupilDiam = CDbl(dlg.TextBox2) J['pBlEb\  
    End If U]!~C 1cmw  
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    Print " " E'_3U5U  
    Print "Accommodation = " & A & " Diopters" 3<c_`BWu  
    Print "Pupil Diameter = " & pupilDiam & " mm" zTP|H5HyK  
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    ' Calculate new parameters with accommodation C"X; ,F<  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness >fX_zowX  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens )?L  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ExJch\  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens x^0MEsR  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens QC/%|M0 {  

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    tlens = 3.767 + 0.04*A                  'Lens thickness ?+^vU5b1u  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction {`X O3  
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    'Adjust parameters to account for accommodation 57nSyd]PR  
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    '************************************************************************* vh29mzum  
    'Aqueous thickness (Position of Lens) yu^n;gWH  
    '************************************************************************* Vdpvo;4uy  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ;s$bVGHr  
    GetCustomElement eID, entity Imv]V6"D=  
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    parID = FindFullName( "Geometry.Arizona Eye" ) ^nPk;%`0  
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    ' Delete any shift(s) in z Y2Z<A(W  
    count = 0 PPj_
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    While GetOperationCount(eID)>count _T8o
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        GetOperation eID, count, op 8Q
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        If op.Type="ShiftZ" Then /E%r@Rui3$  
            DeleteOperation eID,count mrc% 6Ri  
            count=count-1 ~a5-xWEZ  
        End If #RN"Ul-B|  
        count=count+1 xoT|fgb  
    Wend szZ8
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    'Set new shift in /kK%}L_D  
    op.Type = "ShiftZ" *{#l0My  
    op.val1 = taq v +$3Z5  
    op.parent = parID 3M@!?=|U  
    AddOperation eID, op v \xuq`  
    Print "Set aqueous humor thickness = " & taq-0.55 }\-"L/D?+  
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    '************************************************************************* _,G^#$pH  
    'Radius and conic constant of anterior lens <E&[sQ|3  
    '************************************************************************* |^&j'k+A  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" )  ~[wh  
    GetConic eID, entity, curv, conic =o<iBbK#|  
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    SetConic eID, entity, 1/Rant, CCant df'xx)kW  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 2{`[<w  
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    '************************************************************************* |1rKGDc  
    'Radius and conic constant of posterior lens 8Ev,9  
    '************************************************************************* 8`$lsD  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) m0$
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    GetConic eID, entity, curv, conic N.l
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    SetConic eID, entity, 1/Rpost, CCpost c^%vyBMY  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost l&2}/A  
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    '************************************************************************* /&T"w,D  
    'Lens thickness (Position of posterior lens surface) --t5jSS44  
    '************************************************************************* DXH"`1[-  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) yn;sd+:z  
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    ' Delete any z-shift(s) u#>*"4Q  
    count = 0 %K$f2):  
    While GetOperationCount(eID)>count QnJ(C]cW  
        GetOperation eID, count, op Fh3>y2`/  
        If op.Type="ShiftZ" Then [=otgVteN"  
            DeleteOperation eID,count #xlT,:_:)  
            count=count-1 f(}AdW}?  
        End If kpQXnDm2  
        count=count+1 =Eimbk  
    Wend A=+ |&+? t  
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    'Set new z-shift `'gadCTb=  
    op.Type = "ShiftZ" Zd Li<1P*d  
    op.val1 = tlens ^rP` .Z  
    op.parent = parID b5Sgf'B^  
    AddOperation eID, op AfV a[{E  
    Print "Set lens thickness = " & tlens )q>mt/,  
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    '************************************************************************* cc %m0p  
    'Lens index of refraction );~JyoDo  
    '************************************************************************* ;<?mMi@<E  
    eID = FindMaterial( "Lens" ) j1sZRl)D  
    GetModelMaterial eID, mat B7R*g,(  
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    mat.Nd = nlens 555*IT3b
 
    SetModelMaterial eID, mat e2@{Ab  
    Print "Set lens index of refraction = " & nlens GmJ4AYEP  
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    '************************************************************************* "PI]k  
    'Pupil diameter ZtFOIb*  
    '************************************************************************* ;rK= jz^Q  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) <691pkX  
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    'Adjust pupil diameter (trimming volume inner hole) ~%8T_R/3  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" qVpV ZH!  
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    ' Adjust pupil location to just in front of the lens 7v8V0Gp  
    parID = FindFullName( "Geometry.Arizona Eye" ) VPAi[<FzOG  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) u3Qm"?$`  
    count = 0 bIR&e E  
    While GetOperationCount(eID)>count ";PW#VHC  
        GetOperation eID, count, op 7tEkQZMDI  
        If op.Type="ShiftZ" Then &:3uK`  
            DeleteOperation eID,count A
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            count=count-1 bu j}pEI  
        End If "G&S`8  
        count=count+1 ?c$z?QTMJ  
    Wend "Q>gQKgL  
    op.Type = "ShiftZ" d5hYOhO[  
    op.val1 = taq-0.01 \m\E*c ):  
    op.parent = parID 6hW ~Q  
    AddOperation eID, op VN5UJ!$?J  
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    Print "Set pupil diameter = " & pupilDiam "k0bj>  
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    'Update AZ Eye subassembly Description &N`s@K
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    eID = FindFullName( "Geometry.Arizona Eye" ) 5\?\|*WT  
    GetEntity eID, entity a (mgz&*  
    entity.Description = "Accommodation = " & A & "D" _yu d  
    SetEntity eID, entity 3 W%Bsqn  
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    Update 5f` a7R  
    Print "DONE!" y,.X5#rnX*  
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End Sub 6ojEEM  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： vz[-8m:f  
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Accommodation = 4 Diopters N 9.$--X}D  
Pupil Diameter = 4 mm rmzM}T\20  
Set aqueous humor thickness = 2.81 &J <km  
Set anterior lens radius = 10.4 and conic constant = -2.375869 4Z&i\#Q  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 $wQk
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Set lens thickness = 3.927 vLc7RL  
Set lens index of refraction = 1.42672
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Set pupil diameter = 4 aT]G&bR?  
DONE! D.i(Irqw!