[分享]Arizona眼睛模型 [复制链接]

简介 k{^iv:  
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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。 }&EdA;/o_  
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模型 SFqq(K2u  
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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。 *+J`Yk7}  
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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. 4}<[4]f?|  
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光源 `>k7^!Ds  
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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。 ?"p.Gy)  
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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。 LlbE]_Z!U%  
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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。 ban;HGGNG{  
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视网膜的散射 S$nEflcz  
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在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 F\+!\b*lP  
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注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 K`kWfPwp  
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脚本 F2$?[1^f  
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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： ztV%W6  
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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。 h.aXW]]}(P  
余下的脚本计算与屈光度有关的所有参数。 cb_nlG!  
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分析 r} a,  
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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。 3x E^EXV  
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脚本代码 3xpygx9
 
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Option Explicit     'Remove this to enable non-dimensioned variables to be used. jN sM&s,  
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Dim entity As T_ENTITY A
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Dim op As T_OPERATION O29GPs  
Dim mat As T_MODELMATERIAL c4FU@^Vv  
Dim A As Double r%` |kN  
Dim pupilDiam As Double cu"ge]},  
Dim eID As Long | <- t  
Dim parID As Long W^1)7
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Dim count As Integer ^ V8?6E  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double 5`1p ?  
Dim tlens As Double, nlens As Double XM?C7/^k  
Dim curv As Double, conic As Double Xe<kd
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Dim ok As Long Hr;\}  
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Sub Main ]0myoWpi3  
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    '用户输入对话框 w:@W/e*9N  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 Ve\P,.  
        TextBox 220,21,40,21,.TextBox1 'default: 0 X6EnC57  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 #:}mi;{  
        OKButton 40,91,90,21 _l&.<nz  
        CancelButton 190,91,90,21 )zvjsx*e=J  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 `'/1Ij+  
        TextBox 220,49,40,21,.TextBox2 'default: 4 uE,j$d  
    End Dialog ?bl9e&
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    Dim dlg As UserDialog 0tP{
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    ok = Dialog (dlg) fZrB!\Q  
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    If ok=0 Then    'cancel button was pressed NPE7AdB8  
        Print "Execution cancelled." ^uWj#  
        End #i[V{J8.p  
    End If ,HfdiGs}j  
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    'Assign accommodation and pupil diameter & use defaults if field left empty M0"}>`1lJ  
    If dlg.TextBox1 = "" Then Xm[Cgt_?  
        A = 0           'Default accommodation q%8Ck)xz  
    Else #l-/!j  
        A = CDbl(dlg.TextBox1) 17B`  
    End If ;2iDa  
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    If dlg.TextBox2 = "" Then @7OE:& #V  
        pupilDiam = 4   'Default pupil diameter -bQi4  
    Else YEhPAQNj  
        pupilDiam = CDbl(dlg.TextBox2) h v/+  
    End If c"^g*i2&0  

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    Print " " "!_,N@\t  
    Print "Accommodation = " & A & " Diopters" 5D`!Tu3  
    Print "Pupil Diameter = " & pupilDiam & " mm" yo"!C?82=  
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    ' Calculate new parameters with accommodation |NXe{q7{  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness :A]CD(  
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    Rant = 12.0 - 0.4*A                     'Radius of anterior lens .Sjg  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens %pr}Xs(-f  
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    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens ed4`n
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    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens HWi: CDgm  
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    tlens = 3.767 + 0.04*A                  'Lens thickness t Ai?Bjo  
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    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction X16r$~Pb  
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    'Adjust parameters to account for accommodation udGZ%Mr_  
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    '************************************************************************* tY6QhhuS:  
    'Aqueous thickness (Position of Lens) \6K1Z!*;  
    '************************************************************************* vON1\$bu`  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) ,U#FtOec  
    GetCustomElement eID, entity 5WU?Km  
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    parID = FindFullName( "Geometry.Arizona Eye" ) $BWA=2$  
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    ' Delete any shift(s) in z Lo^gg#o  
    count = 0 _cD-E.E%  
    While GetOperationCount(eID)>count |A19IXZ\  
        GetOperation eID, count, op Q804_F F#  
        If op.Type="ShiftZ" Then m005*>IY  
            DeleteOperation eID,count T96M=?wh!  
            count=count-1 _"'0^F$I  
        End If >J_%'%%f  
        count=count+1 wBIhpiJX0  
    Wend 73>Hzpv0  
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    'Set new shift in W`` 
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    op.Type = "ShiftZ" -x2&IJ!  
    op.val1 = taq W#lt_2!j  
    op.parent = parID B*T;DE   
    AddOperation eID, op `Uy'YfYF  
    Print "Set aqueous humor thickness = " & taq-0.55 :}p<Hq 8Z  
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    '************************************************************************* '"fZGz?  
    'Radius and conic constant of anterior lens 2kVQ#JyuRI  
    '************************************************************************* bd@1j`i  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) vN3uLz'<  
    GetConic eID, entity, curv, conic #JW~&;  
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    SetConic eID, entity, 1/Rant, CCant j<C p&}X  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant !S5_+.U#  
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    '************************************************************************* <J.-fZS%  
    'Radius and conic constant of posterior lens #x[3@zP.  
    '************************************************************************* F=r`'\JV[  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) x|q|> dPB  
    GetConic eID, entity, curv, conic wl:[Ad
 
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    SetConic eID, entity, 1/Rpost, CCpost |&0zAP"\  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost mVdg0  
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    '************************************************************************* 9Jj:d)E>o  
    'Lens thickness (Position of posterior lens surface) A,
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    '************************************************************************* LP:F'Q:<  
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    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) rX@?~(^ML  
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    ' Delete any z-shift(s) 19 <Lgr  
    count = 0 J^)=8cy  
    While GetOperationCount(eID)>count fs6% M]u  
        GetOperation eID, count, op ^muPjM+D  
        If op.Type="ShiftZ" Then r>3y8
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            DeleteOperation eID,count KB6`OT^b{r  
            count=count-1 )ME'qA3K  
        End If u:GDM  
        count=count+1  ua]?D2  
    Wend C}8 3t~Q  
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    'Set new z-shift YH/3N(],  
    op.Type = "ShiftZ" 8bI;xjK^Q  
    op.val1 = tlens m.2=,,r<Fq  
    op.parent = parID 2}jC%jR2  
    AddOperation eID, op J{h?=vK  
    Print "Set lens thickness = " & tlens d+Au`'{>  
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    '************************************************************************* g]Fm%iy  
    'Lens index of refraction ypV>*  
    '************************************************************************* fe$OPl~  
    eID = FindMaterial( "Lens" ) gO
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    GetModelMaterial eID, mat 8lfKlXR78  
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    mat.Nd = nlens cOo@UU P  
    SetModelMaterial eID, mat a<d$P*I(cH  
    Print "Set lens index of refraction = " & nlens qF57T>v|  
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    '************************************************************************* do&0m[x%  
    'Pupil diameter ?2i\ERG?  
    '************************************************************************* 9G=H
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    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) x3]y*6  
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    'Adjust pupil diameter (trimming volume inner hole) MMS#Ci=Lj  
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    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" <Pg<F[eDM  
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    ' Adjust pupil location to just in front of the lens mj_V6`m4  
    parID = FindFullName( "Geometry.Arizona Eye" ) >a$b4 pvh  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Fooa~C"  
    count = 0 !y syb  
    While GetOperationCount(eID)>count o]O  
        GetOperation eID, count, op E!zAUEVQm[  
        If op.Type="ShiftZ" Then qS}pv  
            DeleteOperation eID,count #xTu {  
            count=count-1 d6ABgQi0  
        End If |VE*_G  
        count=count+1 xA {1XS}  
    Wend ;/|3U7{c  
    op.Type = "ShiftZ" IM9P5?kJ ?  
    op.val1 = taq-0.01 [>wvVv  
    op.parent = parID V07? sc<  
    AddOperation eID, op R'1L%srTM+  
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    Print "Set pupil diameter = " & pupilDiam aT`. e  
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    'Update AZ Eye subassembly Description '1te(+;e@  
    eID = FindFullName( "Geometry.Arizona Eye" ) $mZpX:7/u8  
    GetEntity eID, entity %5|DdpES  
    entity.Description = "Accommodation = " & A & "D" }}MZgm~U)  
    SetEntity eID, entity JwMFu5@  
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    Update QQIU5  
    Print "DONE!" IWD21lS  
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End Sub SF?s^  
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如果屈光度是4，光瞳直径是4，则会输出如下数据： .,7ZDO9{  
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Accommodation = 4 Diopters g{%2*{;i  
Pupil Diameter = 4 mm 3PU'd^  
Set aqueous humor thickness = 2.81 aB+B1YdY"  
Set anterior lens radius = 10.4 and conic constant = -2.375869 h&$,mbEoI  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 [tY+P7j9)  
Set lens thickness = 3.927 iz pFl@WS  
Set lens index of refraction = 1.42672 96.Vm*/7  
Set pupil diameter = 4 I7/X6^/}  
DONE! 6K 6uB ~  
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