[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 %PQldPL8  
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。 Yw~;g:
=  
ur/Oc24i1n  
模型 84[|qB,ML  
0M#N=%31  
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。 tSEA999  
sTKab :  
4r_!>['`"  
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. -d|BO[4j  
?-pxte8  
光源 9"WRIHt'c  
a
);O3N/*I  
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。 "t5 +*  
?gd'M_-J,  
((-aC`  
8s QQK.N(  
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。 D-Bv(/Pz]$  
-/M9 vS  
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。 JZ %`%rA  
}Q`/K;yq  
t*o7,  
,]f),;=  
视网膜的散射 eZynF<i  
jv*Dg (  
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。 rU; g0'4e  
S8*^ss>?^R  
AU0$A403  
S#P+B*v  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 u
tq.r_  
V)2"l"Kt  
x HY+q;  
])N|[|$  
脚本 >ysriPnQ  
h^['rmd  
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： nA>*IU[  
:L]-'\y  
_mw13jcN]  
dj3|f{kg{  
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。 '!pAnsXfO  
余下的脚本计算与屈光度有关的所有参数。 =ZG<BG_  
XlRw Z/Wc  
分析 buRhQ"  
A)OdQFet(  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 u06tDJ[  
U%Dit  
h{\t*U54'  
脚本代码 MO[c0n%  
<H<!ht%q3  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. )y6QAp  
 NI^{$QMj  
Dim entity As T_ENTITY Z#CxQ D%\  
Dim op As T_OPERATION {":c@I  
Dim mat As T_MODELMATERIAL M#`{>R|  
Dim A As Double TKK,Y{{  
Dim pupilDiam As Double aZP2
R"  
Dim eID As Long :){)JZ}-95  
Dim parID As Long bi+9R-=&  
Dim count As Integer Cm^Ylp  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double Xc{ZN1 4n  
Dim tlens As Double, nlens As Double 9`&?hi49nK  
Dim curv As Double, conic As Double ol50d73B  
Dim ok As Long w_\nB}_  
iA]DE`S  
Sub Main VXiui'/(  
[9LxhPi  
    '用户输入对话框 [Uswf3  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 RZ*<n$#6  
        TextBox 220,21,40,21,.TextBox1 'default: 0 Jl\'V
  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 U4]30B{;H  
        OKButton 40,91,90,21 ?fB5t;~E  
        CancelButton 190,91,90,21 =`JW1dM  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 )5U!>,fT  
        TextBox 220,49,40,21,.TextBox2 'default: 4 g#w`J\iz  
    End Dialog ;"D~W#0-v  
    Dim dlg As UserDialog -=5EbNPwG  
xF&6e&nv  
    ok = Dialog (dlg) vlvvi()  
_wmI(+_  
    If ok=0 Then    'cancel button was pressed <o2,HTWNPS  
        Print "Execution cancelled." ^1R"7h  
        End Mw+v"l&mU  
    End If 3\1#eK'TK.  
-ovoRI^6`}  
    'Assign accommodation and pupil diameter & use defaults if field left empty B& "RS  
    If dlg.TextBox1 = "" Then d)\2U{  
        A = 0           'Default accommodation hzv3F9.x  
    Else .wP/ai>}  
        A = CDbl(dlg.TextBox1) ;ed#+$Na  
    End If w\Iqzpikr  
t-x[:i  
    If dlg.TextBox2 = "" Then },&h[\N{6  
        pupilDiam = 4   'Default pupil diameter pp<E))&R  
    Else 4oV {=~V  
        pupilDiam = CDbl(dlg.TextBox2) pziq
0  
    End If X~Cq  
l~NEGb  
    Print " " *Z >  
    Print "Accommodation = " & A & " Diopters" *U_S1>0n  
    Print "Pupil Diameter = " & pupilDiam & " mm" z{=v)F5y  
##v`(#fu  
    ' Calculate new parameters with accommodation vTHq)
C.7G  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness $2QYxY9s  
V3Yd&HVWNQ  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens lY8`5Uz  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens nZxSMN0]  
8TW5(f
l  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens GB=bG%Tb  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens )nOE8y/  
TtZ}
"MPZ  
    tlens = 3.767 + 0.04*A                  'Lens thickness AX;c}0g  
=DC3a3&%  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction s%O Y<B@V2  
eVx~n(m!}  
    'Adjust parameters to account for accommodation \s
ITwPA[z  
Q ?^4
\_  
    '************************************************************************* ]+ZM/'X  
    'Aqueous thickness (Position of Lens) {yS;NU`2  
    '************************************************************************* )b9_C O}  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) !VRo*[yD@  
    GetCustomElement eID, entity uFo/s&6K  
C `6S}f,  
    parID = FindFullName( "Geometry.Arizona Eye" ) s&VOwU  
o,*=$/or  
    ' Delete any shift(s) in z WL1\y|  
    count = 0 Pj&A=  
    While GetOperationCount(eID)>count `;cz;"  
        GetOperation eID, count, op tDt :^Bc  
        If op.Type="ShiftZ" Then 6OtVaT=}<O  
            DeleteOperation eID,count GyK(Vb"h6  
            count=count-1 bcn7,ht  
        End If ]Jn2Ra"j  
        count=count+1 @vt$MiOi  
    Wend VE$t%QT  
Kp&3=e;vn{  
    'Set new shift in l `R KqT+  
    op.Type = "ShiftZ" "mA1H]r3  
    op.val1 = taq `XgFga)  
    op.parent = parID PS}73Y#  
    AddOperation eID, op d@ (v
g  
    Print "Set aqueous humor thickness = " & taq-0.55 ({ k7#1 h8  
>pdnCv_c  
    '************************************************************************* ?oKL&I@  
    'Radius and conic constant of anterior lens i/*,N&^  
    '************************************************************************* ISBF\ wQY  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) *)D1!R<\,R  
    GetConic eID, entity, curv, conic >f@ G>H)+  
]2$x|#Gg}  
    SetConic eID, entity, 1/Rant, CCant `{o$F ::(  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant OaaH$B  
8wmQ4){  
    '************************************************************************* V;;#/$oU:4  
    'Radius and conic constant of posterior lens .&|L|q}  
    '************************************************************************* (O0byu}  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) NzlAC  
    GetConic eID, entity, curv, conic v2>Z^  
M*`hDdS  
    SetConic eID, entity, 1/Rpost, CCpost 8UM0vNk  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost #xp(B5  
~OCZz$qA  
    '************************************************************************* ]0-<>  
    'Lens thickness (Position of posterior lens surface) YlKFw|=  
    '************************************************************************* D/:3RZF  
`eD1|Go9  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) 5v|EAjB6o  
MGaiTN^_<  
    ' Delete any z-shift(s) u"Y]P*[k  
    count = 0 [.&[<!,.  
    While GetOperationCount(eID)>count "dtlME{Bx  
        GetOperation eID, count, op NwpS)6<-  
        If op.Type="ShiftZ" Then ti2  
            DeleteOperation eID,count =/}X$,@2  
            count=count-1 HeozJ^u\?  
        End If mb{q(WEPP  
        count=count+1 @GeHWv  
    Wend <5IQc[3]aP  
Uk'U?9O  
    'Set new z-shift
S>t>6
&A  
    op.Type = "ShiftZ" "+h/
-2rA  
    op.val1 = tlens yU_9a[$V  
    op.parent = parID T*+A.G@L"  
    AddOperation eID, op '[0YIn  
    Print "Set lens thickness = " & tlens @i1q]0  
-nR\,+N  
    '************************************************************************* bEI!Ja  
    'Lens index of refraction U^?= 0+  
    '************************************************************************* (U9a@1  
    eID = FindMaterial( "Lens" ) 3U;1D2"AE  
    GetModelMaterial eID, mat e U;jP]FA  
Y/lN@  
    mat.Nd = nlens ti9}*8  
    SetModelMaterial eID, mat P {H{UKs#  
    Print "Set lens index of refraction = " & nlens vr4S9`,  
] .5OX84  
    '************************************************************************* - _t&+5]  
    'Pupil diameter WQKj]:qk0  
    '************************************************************************* ZqK]jT6V/X  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" )  AP w6  
HJ@5B"  
    'Adjust pupil diameter (trimming volume inner hole) lRND  
(oYW]c}G,  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" \_U*t!  
*Hu
np Y  
    ' Adjust pupil location to just in front of the lens ug&92Hdvy3  
    parID = FindFullName( "Geometry.Arizona Eye" ) XA3s],Rk  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) SdI1}&  
    count = 0 w~N-W8xNR  
    While GetOperationCount(eID)>count _]o5R7[MQ  
        GetOperation eID, count, op X4
Xf2aXI  
        If op.Type="ShiftZ" Then o5 WW{)Q  
            DeleteOperation eID,count hk;bk?:m  
            count=count-1 784;]wdy\  
        End If TQ'e  
        count=count+1 :Tb7r6  
    Wend w1i?#!|  
    op.Type = "ShiftZ" Euu ,mleM  
    op.val1 = taq-0.01 #T"64%dX  
    op.parent = parID 3cThu43c  
    AddOperation eID, op q%S8\bt  
I
?M@5u  
    Print "Set pupil diameter = " & pupilDiam J"&y|;G  
N^J*!]|  
    'Update AZ Eye subassembly Description &t6Tcy  
    eID = FindFullName( "Geometry.Arizona Eye" ) ";dU-\3M  
    GetEntity eID, entity fU ={a2  
    entity.Description = "Accommodation = " & A & "D" oMc1:=EG  
    SetEntity eID, entity W~NYU  
4B$bj`h  
    Update 38wq (  
    Print "DONE!" H,|YLKg-|  
     g1V)$s7  
End Sub +^gO/0  
%wW'!p-<  
如果屈光度是4，光瞳直径是4，则会输出如下数据： ^PQM;"  
or.\)(m#(  
Accommodation = 4 Diopters z2~87fv+  
Pupil Diameter = 4 mm -tyaE  
Set aqueous humor thickness = 2.81 ]M\q0>HoJ  
Set anterior lens radius = 10.4 and conic constant = -2.375869 e5OVq ,  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 s<VJ`Ur  
Set lens thickness = 3.927 \Tkp  
Set lens index of refraction = 1.42672 e&Rb  
Set pupil diameter = 4 FmI;lVF0j  
DONE! $5L(gn[  
L[.<o{