[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介  jPC[_g  
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。 b IH;  
CWf /H)~  
模型 \@-@Y  
x
qXo0  
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。 *w$W2I>b7  
(ScxLf=]  
!ds
"9w
 
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. /Y*WBTV'  
1da@3xaF  
光源 JBD7h5|Lc  
_geWE0 E  
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。 A]y`7jJ  
'QG xd!4  
_G_Cj{w  
".f ;+wH  
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。 *xc_k
"\  
T`/AY?#  
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。 ylUb9KusOx  
{qDSPo  
|D'4uN8\  
f'8kish  
视网膜的散射 7t3X)Ah  
h}-3\8 >  
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。 +O'3|M  
"B8Q:  
-_ I_
W&  
3sc+3-TF  
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。 c@YI;HS_g  
"
-y-iJ  
Ulhk$CPA  
k2E0/ @f{k  
脚本 "vA}FV%tRq  
s.EI`*xylY  
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： O[# 27_dH  
M-\Y"]sW  
nvca."5y  
S(QpM.9*  
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。 Yi .u"sh]  
余下的脚本计算与屈光度有关的所有参数。 WJ)z6m]  
M]
<?k]_p  
分析
U -Y03  
\Fl+\?~D  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 M=.:,wRm  
<wZQc  
!P ~_Dl2d  
脚本代码 V=)_yIS  
3WN`y8l  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. k-Q%.o  
z+ s6)Ad  
Dim entity As T_ENTITY hZ[E7=NTQ^  
Dim op As T_OPERATION Yv hA_v  
Dim mat As T_MODELMATERIAL UYFwS/ RW}  
Dim A As Double U0=]  
Dim pupilDiam As Double  rL/H2[d  
Dim eID As Long r/& sub"X  
Dim parID As Long uC.K<jD%  
Dim count As Integer 2#o>Z4 r{  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double D@G\7KH@  
Dim tlens As Double, nlens As Double `J]fcE%T0R  
Dim curv As Double, conic As Double S2n39 3  
Dim ok As Long .id)VF-l  
+U_=*"@|  
Sub Main El<]b7  
R,)}>X|<
 
    '用户输入对话框 8iW;y2qF  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 7:Ax(El  
        TextBox 220,21,40,21,.TextBox1 'default: 0 u83J@nDQ  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1
M@h|bN  
        OKButton 40,91,90,21 e'~Zo9`r6  
        CancelButton 190,91,90,21 m#ZO`W  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 +$X#q8j06  
        TextBox 220,49,40,21,.TextBox2 'default: 4 .7zK@6i  
    End Dialog ~jK{ ,$:=  
    Dim dlg As UserDialog )=\#UE+W  
"8'@3$>R=  
    ok = Dialog (dlg) ]DZE%  
U;bK!&Z  
    If ok=0 Then    'cancel button was pressed y+!+ D[x  
        Print "Execution cancelled." iY`%SmB  
        End )v]/B+  
    End If RZ6xdq}>  
N+zKr/  
    'Assign accommodation and pupil diameter & use defaults if field left empty ;WgJ<&33  
    If dlg.TextBox1 = "" Then t^`O{m<  
        A = 0           'Default accommodation DKfE.p)  
    Else *"WDb|PBb  
        A = CDbl(dlg.TextBox1) cKN$ =gd  
    End If |_}2f  
Kh(ZU^{n  
    If dlg.TextBox2 = "" Then D,;\o7V  
        pupilDiam = 4   'Default pupil diameter !E,A7s  
    Else mK[)mC _8  
        pupilDiam = CDbl(dlg.TextBox2) 994`ua+  
    End If M(RZ/x  
`
L>  
    Print " " <WjF*x p  
    Print "Accommodation = " & A & " Diopters" hj  
    Print "Pupil Diameter = " & pupilDiam & " mm" o[v\|Q`d  
$KUos+%  
    ' Calculate new parameters with accommodation z?[r  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness Dw=gs{8D  
6&DX] [G  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens $BkubWM  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ^M%uV  
;l&4V  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens `Q+(LBP  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens I#m-g-J  
LVc4CE f  
    tlens = 3.767 + 0.04*A                  'Lens thickness *5 |)-E  
)'/|)  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Rp*R:3 C  
YFE&r  
    'Adjust parameters to account for accommodation @

Ukr  
#Y0-BYa^  
    '************************************************************************* rEHkw '  
    'Aqueous thickness (Position of Lens) !FA# K8  
    '************************************************************************* o }3uo6GIB  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) B.g[c97  
    GetCustomElement eID, entity s <   
+j(d| L\  
    parID = FindFullName( "Geometry.Arizona Eye" ) "Vw m  
?pYKZg/c  
    ' Delete any shift(s) in z *+TH#EL2  
    count = 0 nl(
WJKq'  
    While GetOperationCount(eID)>count )+6v  
        GetOperation eID, count, op :ml2.vP  
        If op.Type="ShiftZ" Then G P:FSprP  
            DeleteOperation eID,count 89n:)|rWq  
            count=count-1 `W dD8E  
        End If
CbPuoOl  
        count=count+1 %FS$zOsgGK  
    Wend N=5)fe%{4  
>$
NDv  
    'Set new shift in 2pzF5h  
    op.Type = "ShiftZ" %VzKqh  
    op.val1 = taq \A#1y\ok  
    op.parent = parID HD
da@Jy  
    AddOperation eID, op fwrJ!j  
    Print "Set aqueous humor thickness = " & taq-0.55 -zp0S*iP7  
-+7uy.@cS  
    '************************************************************************* A a=u+  
    'Radius and conic constant of anterior lens y"6y
!  
    '************************************************************************* 7_.11$E=H  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Rl
qQ  
    GetConic eID, entity, curv, conic -b9;5eS!  
UPc<gB  
    SetConic eID, entity, 1/Rant, CCant M t*6}Cl  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant /,MJq#@K  
zaFt*~@X  
    '************************************************************************* Kx.X
7R  
    'Radius and conic constant of posterior lens .s<*'B7&  
    '************************************************************************* 9Ro6fjjE  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) yf
jK2  
    GetConic eID, entity, curv, conic y kW [B  
j:}J}P  
    SetConic eID, entity, 1/Rpost, CCpost `%E8-]{uS  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost cooUE<a  
s0*0 'f  
    '************************************************************************* EyI}{6~F  
    'Lens thickness (Position of posterior lens surface) cXR1grz  
    '************************************************************************* rwniOQe  
~`GhS<D  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) LAP6U.m'd  
?_oF:*~\  
    ' Delete any z-shift(s) Dy]I8_  
    count = 0 ~%/Wupf  
    While GetOperationCount(eID)>count m6MOW&  
        GetOperation eID, count, op RP2_l$  
        If op.Type="ShiftZ" Then .MVYB\6Q0  
            DeleteOperation eID,count 6vp *9  
            count=count-1 8>7Rx
SF  
        End If +B'8|5tPX  
        count=count+1 g ^!C  
    Wend 7_wJpTz  
65oWD-  
    'Set new z-shift ]Ni;w]KE  
    op.Type = "ShiftZ" Nrah;i+H\o  
    op.val1 = tlens !Oj)B1gc6&  
    op.parent = parID Z2Zq'3*  
    AddOperation eID, op k-E{d04-2  
    Print "Set lens thickness = " & tlens "c(Sysl.L  
TgTnqR@/  
    '************************************************************************* f`8OM}un&  
    'Lens index of refraction F( Ak  
    '************************************************************************* j}F-Xs+  
    eID = FindMaterial( "Lens" ) v[TYc:L=  
    GetModelMaterial eID, mat ?sBh=Ds  
dl5=q\1=  
    mat.Nd = nlens \ A%eG&  
    SetModelMaterial eID, mat ckjrk  
    Print "Set lens index of refraction = " & nlens 7l."b$U4yv  
z305{B:Y  
    '************************************************************************* :s-o0$PlJ  
    'Pupil diameter DY{cQb  
    '************************************************************************* nRb^<cZf  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) wNNB;n`l  
)9B:wc"
 
    'Adjust pupil diameter (trimming volume inner hole) v)f7};"z   
/ahNnCtu?1  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 1|ZhPsD.}g  
3L_I[T$s  
    ' Adjust pupil location to just in front of the lens LF?P> 1%-  
    parID = FindFullName( "Geometry.Arizona Eye" ) ?-OPX_i_  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 4KI
[D{  
    count = 0 _Mc>W0'5@  
    While GetOperationCount(eID)>count y/? &pKH^  
        GetOperation eID, count, op m7=1%6FN3  
        If op.Type="ShiftZ" Then NQ|xM"MqD  
            DeleteOperation eID,count 3Z>YV]YbeU  
            count=count-1 2X88:  
        End If |<`.fOxJP  
        count=count+1 maSgRf[g  
    Wend -$<O\5cAQ  
    op.Type = "ShiftZ" (QB+%2v  
    op.val1 = taq-0.01 J$9:jE-4  
    op.parent = parID h?UVDzI!O  
    AddOperation eID, op hzY[ G:  
G",.,Px  
    Print "Set pupil diameter = " & pupilDiam yg;_.4TpIO  
Y\+KoR';  
    'Update AZ Eye subassembly Description R4e&^tI@*  
    eID = FindFullName( "Geometry.Arizona Eye" ) PoShQR<  
    GetEntity eID, entity p"`
%  
    entity.Description = "Accommodation = " & A & "D"  >0Ev#cX4  
    SetEntity eID, entity C+K=[

 
ekQrW%\3  
    Update %*z-PT22  
    Print "DONE!" DB`QsiC)  
     ~^N]yb  
End Sub b^`AJK  
kII7z;<^`  
如果屈光度是4，光瞳直径是4，则会输出如下数据： :Dl%_l  
WW "i  
Accommodation = 4 Diopters .~=HgOJ  
Pupil Diameter = 4 mm $v}<'  
Set aqueous humor thickness = 2.81 fP%Fyg^k  
Set anterior lens radius = 10.4 and conic constant = -2.375869 :DkAQ-<~  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 _qWC4NMF(  
Set lens thickness = 3.927 hPdx(E)8!d  
Set lens index of refraction = 1.42672 zPZF|%|  
Set pupil diameter = 4 0y%L-:/c|  
DONE! 8NimZ(  
8 #oR/Nt