[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 Wzf1-0t  
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。 I!soV0VU]  
J6^Ct  
模型 &ttv4BC^r  
SCt=OdP=  
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。 95gsv\2  
&Curvc1fm  
&[2Ej|o  
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. #)h ~.D{  
=|WV^0=S'%  
光源 )68fm\t(  
bCaPJ!ZO  
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。 >`rNT|rg  
+~i+k~{`H  
hB GGs  
9Sj:nn^/u  
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。 l_j<aCY?|  
|au qj2  
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。 h<^:Nn  
\w0b"p  

,;=( )-  
e ka@?`  
视网膜的散射 1N$gE  
C +?@iMh  
在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 Jr>S/]"  
@y\{<X.F\1  
:2UC{_  
EDidg"0p  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 kFIB lPV  
vb"dX0)<  
va/4q+1GfH  
)D@n?qbG  
脚本 6 XOu~+7  
%d[xr h  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： #!d^3iB2  
|gRgQGeB  
_9-D3_P[3  
tj^:SW.0  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 gy
,TT<1)  
余下的脚本计算与屈光度有关的所有参数。 ?'/5%f`  
G>ptwB81KM  
分析 h^_taAdS`  
?.Yw%{?TG  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 > v!c\  
j.'"CU  
Y\z\{JW  
脚本代码 GWqY$YT  
`i)ePiE  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. FPUR0myCU  
:k )<1ua  
Dim entity As T_ENTITY ^.1VhTB  
Dim op As T_OPERATION &P{p\v2Y  
Dim mat As T_MODELMATERIAL F%+rOT<5  
Dim A As Double "`3^MvC  
Dim pupilDiam As Double TX [%s@C  
Dim eID As Long |m 5;M$M)  
Dim parID As Long X>GY*XU  
Dim count As Integer (F '  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double i`nw"8  
Dim tlens As Double, nlens As Double Q%VR@[`\  
Dim curv As Double, conic As Double [`-O-?=  
Dim ok As Long kq.h\[  
^\kHEM|5v  
Sub Main ,Ho.
O7H  
07"Oj9NlA  
    '用户输入对话框 s>``- ]3  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 U8$dG)PhA  
        TextBox 220,21,40,21,.TextBox1 'default: 0 zcWxyLifl0  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 -QI`npsnV  
        OKButton 40,91,90,21 ;q&D,4r]  
        CancelButton 190,91,90,21 jzA8f+:q  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 hGo|2@sc  
        TextBox 220,49,40,21,.TextBox2 'default: 4 0#/ 6P&6  
    End Dialog c2mt<DtWW  
    Dim dlg As UserDialog cASHgm  
z(X6%p0  
    ok = Dialog (dlg) =egi?Ne  
jsaCnm>
&  
    If ok=0 Then    'cancel button was pressed zomNjy*  
        Print "Execution cancelled." !K~$-jlT  
        End (4f9
wrK  
    End If N&h!14]{Z  
UYrzsUjg&  
    'Assign accommodation and pupil diameter & use defaults if field left empty 'I>#0VRr  
    If dlg.TextBox1 = "" Then 4bzn^  
        A = 0           'Default accommodation D=sc41]  
    Else _";pk _  
        A = CDbl(dlg.TextBox1) }~'Wz*Gm  
    End If de47O  
*>$)#?t  
    If dlg.TextBox2 = "" Then 4^ 6L])y  
        pupilDiam = 4   'Default pupil diameter fToI,FA
 
    Else _1c_TMh}9  
        pupilDiam = CDbl(dlg.TextBox2) 
6jo&i  
    End If 6MNA.{Jdd  
*9(1:N;#  
    Print " " 9ufs6z  
    Print "Accommodation = " & A & " Diopters" Z2jb>%  
    Print "Pupil Diameter = " & pupilDiam & " mm" [gp:nxyfQm  
TPFmSDq  
    ' Calculate new parameters with accommodation /(pChY>  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness
BIf].RY  
slfVQ809  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens \o)4m[oF  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens s;WCz  
J\D3fh97-  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 2B dr#qr  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens l*H"]6cXRL  
\U>Kn_7m  
    tlens = 3.767 + 0.04*A                  'Lens thickness N4jLb
nA  
'k Z1&_{  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction u*N
8s[s'  
Wj=ex3K3u.  
    'Adjust parameters to account for accommodation T=dvc}  
R_n-&d'PP  
    '************************************************************************* tgA |Vwwk  
    'Aqueous thickness (Position of Lens) Hvo27THLo  
    '************************************************************************* z5
vI0 N$  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) _u2  
    GetCustomElement eID, entity 5305N!  
ye2Oh7  
    parID = FindFullName( "Geometry.Arizona Eye" ) PzDgl6C  
-V<"Ay  
    ' Delete any shift(s) in z p,Hk"DSs%  
    count = 0 ~"Ki2'j)^]  
    While GetOperationCount(eID)>count VW`=9T5%@  
        GetOperation eID, count, op n5>N9lc  
        If op.Type="ShiftZ" Then rapca'&#  
            DeleteOperation eID,count 0|;=mYa4M  
            count=count-1 #K w\r50  
        End If 5VbNWrw  
        count=count+1 ]t;5kj/  
    Wend %WN2 xCSf  
Tj9q(Vq  
    'Set new shift in \"Iy<zG  
    op.Type = "ShiftZ" X&Lt?e,&  
    op.val1 = taq &}1)]6q$  
    op.parent = parID c.v)M\:  
    AddOperation eID, op K_n%`
5  
    Print "Set aqueous humor thickness = " & taq-0.55 P$I\)Q H  
'VEpVo/  
    '************************************************************************* Din)5CxFX  
    'Radius and conic constant of anterior lens p]4 sN  
    '************************************************************************* GK&Dd"v  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) fif<[Ax  
    GetConic eID, entity, curv, conic Hp!F?J7sx  
P\e%8&_U/  
    SetConic eID, entity, 1/Rant, CCant xK3;/!\`  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant C<>.*wlp=  
Q>$L;1E*,  
    '************************************************************************* .SN
]hLV5  
    'Radius and conic constant of posterior lens aa/9o]  
    '************************************************************************* uLF55:`<  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) <bI,y_<K  
    GetConic eID, entity, curv, conic 7<D_ h/WV  
[dMxr9M  
    SetConic eID, entity, 1/Rpost, CCpost &=bI3-  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost [_n|n"M  
n TG|Isa  
    '************************************************************************* Vk-_H)*r  
    'Lens thickness (Position of posterior lens surface) K>y+3HN[6  
    '************************************************************************* pdSyx>rJ  
^h=kJR9  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) e$=|-Jz  
kZQ;\QL1}  
    ' Delete any z-shift(s) M.xEiHz  
    count = 0 :xCobMs_/  
    While GetOperationCount(eID)>count BL67sva;  
        GetOperation eID, count, op d%bL_I)  
        If op.Type="ShiftZ" Then ~55>uw<  
            DeleteOperation eID,count y1X.Mvc  
            count=count-1 u:ISwAp  
        End If / yCV-L2J  
        count=count+1 ikQ2x]Sp  
    Wend > R=YF*t  
X6RM2  
    'Set new z-shift B|v fkX2f  
    op.Type = "ShiftZ" CR<l"~X  
    op.val1 = tlens \m&:J>^  
    op.parent = parID A7H=#L+C  
    AddOperation eID, op ?t-2oLE  
    Print "Set lens thickness = " & tlens |4vk@0L  
5 *_#"  
    '************************************************************************* V QI7lJV"  
    'Lens index of refraction G1rgp>m  
    '************************************************************************* ^gG,}GTl  
    eID = FindMaterial( "Lens" ) (C&f~U  
    GetModelMaterial eID, mat ,P^"X5$  
6]VTn-  
    mat.Nd = nlens M:x(_Lu  
    SetModelMaterial eID, mat bPNsy@
"6  
    Print "Set lens index of refraction = " & nlens \XC1/LZQ  
("Zi,3"+  
    '************************************************************************* *3|KbCX  
    'Pupil diameter ^s5)FdF8  
    '************************************************************************* n" sGI  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) bTj,5,8i  
"TPMSx&Ei  
    'Adjust pupil diameter (trimming volume inner hole) Mtu8zm  
qcqf9g  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" RW5T
}  
;\h'A(  
    ' Adjust pupil location to just in front of the lens AOpf
Byw  
    parID = FindFullName( "Geometry.Arizona Eye" ) g(1'i1  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) <javZJ  
    count = 0 3XIxuQwf  
    While GetOperationCount(eID)>count ,~v1NK*  
        GetOperation eID, count, op NJ.kT uk  
        If op.Type="ShiftZ" Then 3hkA`YSYt  
            DeleteOperation eID,count "='|c-
x  
            count=count-1 )j](_kvK  
        End If ][3 "xP  
        count=count+1 52
oR^|  
    Wend FXbNmBXF  
    op.Type = "ShiftZ" sB $!X@  
    op.val1 = taq-0.01 fI6F};I5}T  
    op.parent = parID so;aN'{6@  
    AddOperation eID, op ZEW`?6  
V5=Injs*  
    Print "Set pupil diameter = " & pupilDiam PqfH}d0l  
Epx.0TA=t  
    'Update AZ Eye subassembly Description d97wiE/i<  
    eID = FindFullName( "Geometry.Arizona Eye" ) il:""x7^y  
    GetEntity eID, entity 4WLB,<b}  
    entity.Description = "Accommodation = " & A & "D" + EM '-  
    SetEntity eID, entity  M`
bK   
\o/oM,u  
    Update ~!@a  
    Print "DONE!" Rcu/ @j{O  
     
$lvpBs  
End Sub .NjOaK)\  
<3i!{"}  
如果屈光度是4，光瞳直径是4，则会输出如下数据： IlH*s/  
o^Ms(?K%t  
Accommodation = 4 Diopters L;Nm"[`  
Pupil Diameter = 4 mm .^/OL}/~<  
Set aqueous humor thickness = 2.81 !aLL|}S  
Set anterior lens radius = 10.4 and conic constant = -2.375869 $#CkI09  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 %#= 1?1s  
Set lens thickness = 3.927 (|W@p\Q  
Set lens index of refraction = 1.42672 s+aeP  
Set pupil diameter = 4 ALhu\x>AY  
DONE! q?`bu:yS
 
^*Sb)tu\ W