[技术]Arizona眼睛模型 [复制链接]

简介 .$y'>O*$G  
i0+e3!QU  
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。 :qB|~"9O  
zAklS 7L  
模型 PXtF#,roP  
UA~ 4O Q]  
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。 xz.M'az\  
6=,zkU*i^  
#6D>e~>n  
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. (jyufHm  
/5L\:eX%  
光源 J}8p}8eF,  
 -K8F$\W  
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。 2T(+VeM
Q=  

UmGKj9u  
ir{ 4k  
Oi^cs=}  
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。 |7A}LA  
kn$_X
4^?  
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。 !=*8*?@  
Q_iN/
F  
_&s pMf  
:WQlpLn  
视网膜的散射 _ gYj@ %  
xHaz*w1|  
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。 0} &/n>F  
Ac|dmu  
OA\]|2 :  
ZADMtsk  
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。 'yA/sZ  
_$D!"z7i  
3)?WSOsL:  
-D=Sj@G  
脚本 C%]qK(9vvd  
f`/('}t  
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： hjFht+j
1  
X?< L<:.  
X9FO"(J  
mF+8Q  
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。 ,t wB" *  
余下的脚本计算与屈光度有关的所有参数。 $^?VyHXvY  
A9K$:mL<2  
分析 f>ktv76  
&zEBfr  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 2@z.ory.  
G![4K#~NM  
y6[le*T  
脚本代码 ~re}6-?  
VzHrKI  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. </xf4.C  
##xvuLy-6  
Dim entity As T_ENTITY GtZ.'?-  
Dim op As T_OPERATION /JC1o&z_T  
Dim mat As T_MODELMATERIAL m&xVlS  
Dim A As Double V!^0E.?a  
Dim pupilDiam As Double oxL<\4)WJ  
Dim eID As Long
%3#C0%{x  
Dim parID As Long `#`jU"T|  
Dim count As Integer CZe
Zk  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double h\3-8m  
Dim tlens As Double, nlens As Double VR&dy|5BO  
Dim curv As Double, conic As Double CyYr5 Dz  
Dim ok As Long il!B={  
>8OY6wb  
Sub Main 6<fG;:  
ivq(eKy  
    '用户输入对话框 $*%,  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 `\\s%}vZ*T  
        TextBox 220,21,40,21,.TextBox1 'default: 0 s9nPxC&A  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ysIhUpd  
        OKButton 40,91,90,21 KT<$E!@  
        CancelButton 190,91,90,21 )&>W/56/  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 \$Wpt#V  
        TextBox 220,49,40,21,.TextBox2 'default: 4 Fih pp<  
    End Dialog Gvh"3|u?z  
    Dim dlg As UserDialog 5BXku=M  
FibZT1-k  
    ok = Dialog (dlg) _[Imwu}  
HSROgBNI:  
    If ok=0 Then    'cancel button was pressed pl1CPxSdO  
        Print "Execution cancelled." Bh cp=#  
        End ^4"AWps  
    End If y||RK`H  
z rSPa\M  
    'Assign accommodation and pupil diameter & use defaults if field left empty w@cW`PlF  
    If dlg.TextBox1 = "" Then BPt? 3tC  
        A = 0           'Default accommodation 1@KiP`DA  
    Else ^w~B]*A:"  
        A = CDbl(dlg.TextBox1) [yQ%g;m  
    End If L98T!5)  
r=Lgh#9S  
    If dlg.TextBox2 = "" Then `{Q'iydU  
        pupilDiam = 4   'Default pupil diameter G(#t,}S}@  
    Else Sm4B
ZF~!B  
        pupilDiam = CDbl(dlg.TextBox2) B^P&+,\[}  
    End If H#;*kc a4  
llX `  
    Print " " , %z HykP  
    Print "Accommodation = " & A & " Diopters" ztSQrDbbb4  
    Print "Pupil Diameter = " & pupilDiam & " mm" =N
C??e{  
a0sz$u  
    ' Calculate new parameters with accommodation =r ^_D=  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness \b(&-=(  
-~~h1  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens DWKQ>X6  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens ;;+AdN5  
}p2iF2g9`  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens <Jhd%O
 
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens SU~.baP?  
XxmWj-=qO  
    tlens = 3.767 + 0.04*A                  'Lens thickness ,/b!Xm:  
fy"}# 2  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction b}0h()v  
4y7_P0}:B  
    'Adjust parameters to account for accommodation 1a{3k#}  
Fk3(( n=  
    '************************************************************************* A<)n H=G&  
    'Aqueous thickness (Position of Lens) EyPJ Jc8  
    '************************************************************************* _`\!+qGq  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) oHx:["F  
    GetCustomElement eID, entity H"AL@=  
B1nm?E 0i  
    parID = FindFullName( "Geometry.Arizona Eye" ) ~ `qWEu  
#'s$6gT=  
    ' Delete any shift(s) in z BM /FOY;  
    count = 0 fS4W*P[B3  
    While GetOperationCount(eID)>count \~%+)a%%  
        GetOperation eID, count, op NLL"~  
        If op.Type="ShiftZ" Then *%KIq/V  
            DeleteOperation eID,count xo'!$a}I2  
            count=count-1 )f:i4.M  
        End If a&8K5Z%0  
        count=count+1 "V]*ov&[  
    Wend lgU!D |v  
^w1+b;)  
    'Set new shift in l6HtZ(  
    op.Type = "ShiftZ" Ex p?x  
    op.val1 = taq 08nh y[  
    op.parent = parID &]n }fq  
    AddOperation eID, op Ie^Ed`  
    Print "Set aqueous humor thickness = " & taq-0.55 'M"z3j]m-,  
P knOeW"j  
    '************************************************************************* [6mK<A,/  
    'Radius and conic constant of anterior lens <7J3tn B  
    '************************************************************************* ?Cf'IBpN  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) ]z^jz#>um&  
    GetConic eID, entity, curv, conic wz:e\ !  
Bzwll  
    SetConic eID, entity, 1/Rant, CCant ,ZJ}X 9$<  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Cst1nGPL  
:P_h_Tizv  
    '************************************************************************* qco'neR"z  
    'Radius and conic constant of posterior lens "H(3pl.  
    '************************************************************************* 2v ~8fr4
  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) 1sj7]G]`
k  
    GetConic eID, entity, curv, conic @9 S ::  
^R@)CIQ  
    SetConic eID, entity, 1/Rpost, CCpost 2PSExK57  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost GCN-T1HvA2  
fL2P6N@  
    '************************************************************************* YM_[   
    'Lens thickness (Position of posterior lens surface) cwzkA,e@  
    '************************************************************************* $EFS_*<X  
g3
kbsi7_:  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) \2y/:  
geyCS3 :p  
    ' Delete any z-shift(s) IwnDG;+Ap  
    count = 0 #VX]tr
h,  
    While GetOperationCount(eID)>count i`F5  
        GetOperation eID, count, op /P,1KVQPh  
        If op.Type="ShiftZ" Then LD[\eJ_  
            DeleteOperation eID,count y+iRZ%V^  
            count=count-1 =A6*;T"W  
        End If QHO n?e  
        count=count+1 b_ZvI\H  
    Wend 0j!<eN=  
}~@/r5Zl  
    'Set new z-shift ZUHW*U.  
    op.Type = "ShiftZ" 3\m!  
    op.val1 = tlens $jh$nMx)!  
    op.parent = parID o i'iZX  
    AddOperation eID, op 6t;;Fz  
    Print "Set lens thickness = " & tlens UiV#w#&P  
h<&GdK2U+  
    '************************************************************************* J(#6Cld`c  
    'Lens index of refraction SV t~pE+Y  
    '************************************************************************* dM^EYW  
    eID = FindMaterial( "Lens" ) D@uVb4uK  
    GetModelMaterial eID, mat QYo04`Rl  
||X3g"2W9  
    mat.Nd = nlens JR`$t~0t  
    SetModelMaterial eID, mat K9xvog  
    Print "Set lens index of refraction = " & nlens h!SsIy(  
F;#$Q  
    '************************************************************************* "G>d8GbIh  
    'Pupil diameter ri4z^1\  
    '************************************************************************* IWv5UmjN  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) y_L8i
[  
b(N\R_IQ~  
    'Adjust pupil diameter (trimming volume inner hole) 7 w,D2T  
26aDPTP$<  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" _(J#RH  
MUl7o@{'  
    ' Adjust pupil location to just in front of the lens >U*p[FGW  
    parID = FindFullName( "Geometry.Arizona Eye" ) | I:@:  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) Rnwm6nu  
    count = 0 e4=FO;%  
    While GetOperationCount(eID)>count ':_9o5I
 
        GetOperation eID, count, op +:^l|6%}  
        If op.Type="ShiftZ" Then Eo
J\Jk  
            DeleteOperation eID,count rVP\F{Q4Tr  
            count=count-1 V. i
{IW  
        End If \}h  
        count=count+1 {K+f&75  
    Wend ]CLM'$  
    op.Type = "ShiftZ" -B-G$ii  
    op.val1 = taq-0.01 (]cL5o9  
    op.parent = parID Z#@  
    AddOperation eID, op 
U:8]G  
G8vDy1`q6  
    Print "Set pupil diameter = " & pupilDiam sDNWB_~  
$i+@vbU6  
    'Update AZ Eye subassembly Description M *w{PjU  
    eID = FindFullName( "Geometry.Arizona Eye" ) Qqg.z-G%.  
    GetEntity eID, entity ~.3v\Q  
    entity.Description = "Accommodation = " & A & "D" j=T8b  
    SetEntity eID, entity >z%YKdq  
9NwUXh(:(  
    Update ]:LlOv$  
    Print "DONE!" mOj;0 R  
     &Cb,C+q  
End Sub 8>WA5:]v  
(rhlK} C  
如果屈光度是4，光瞳直径是4，则会输出如下数据： kP$E+L  
V/H+9+B7Im  
Accommodation = 4 Diopters (<>??(VM  
Pupil Diameter = 4 mm ZMlBd}H  
Set aqueous humor thickness = 2.81 v|~=rvXFC  
Set anterior lens radius = 10.4 and conic constant = -2.375869 @.E9ml  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 OF`J{`{r  
Set lens thickness = 3.927 uz+WVmb  
Set lens index of refraction = 1.42672 KwHN c\\  
Set pupil diameter = 4 hNh!H<}|m8  
DONE! eb`3'&zV&)