[分享]Arizona眼睛模型 [复制链接]

简介 i7})V
DsZ  
q]tPsX5{*  
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。 .8CR \-
  
&|H?J,>  
模型 `jJ5us  
S 1|[}nYP  
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。 x<"e} Oo  
U\y];\~H  
/+Xv(B  
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. mz[rB|v"/7  

}(dhXOf\q  
光源 `Y/DttjL  
`w]=xe  
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。 (M6B$:  
0W9,uC2:N  
uA:|#mO  
IyYC).wU}  
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。 *:3flJt  
qr(SAIX"  
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。 C2,,+* v  
cI'&gT5  
vj^vzFbK  
j|KZ HH%dc  
视网膜的散射 Zo22se0)  
R\MM2_I  
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。 29pIO]8;  
|~CN]N  
9~<HTH  
CfoSow-  
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。 yEy} PCJ&  
G1vWHa7n;f  
mKPyM<Q  
@P4fR7  
脚本 ^
x4I  
B+wSLi(  
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： |SZRO,7x  
q/?#+d  
$k V^[  
b|wCR%  
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。 W{At3Bfy  
余下的脚本计算与屈光度有关的所有参数。 ?z171X0  
AIF?+i%H}  
分析 N0sf V  
r@H<@Vuc  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 (
+38z)f  
y1(smZU  
Xp
{+){Iu  
脚本代码 b"t!nfgo  
Ja|! fT  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. "CB*  
WsTbqR)W%  
Dim entity As T_ENTITY $OHY^IE(  
Dim op As T_OPERATION |%g^6RN  
Dim mat As T_MODELMATERIAL #q%xJ[  
Dim A As Double D!ToCVos  
Dim pupilDiam As Double j Aw&5,  
Dim eID As Long )
$I;)`q  
Dim parID As Long O$E3ry+?  
Dim count As Integer 9l@VxX68M  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double uR|Jn)/m(  
Dim tlens As Double, nlens As Double ,o]"G[J
k  
Dim curv As Double, conic As Double m\__F
l  
Dim ok As Long .ZFs+8qU>  
gdRwh  
Sub Main } '.l'%  
=4"D8UaHr  
    '用户输入对话框 t]#y}V  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 4iBp!k7  
        TextBox 220,21,40,21,.TextBox1 'default: 0 G\?fWqx  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ec[
S?-  
        OKButton 40,91,90,21 r+217fS>  
        CancelButton 190,91,90,21 su
N{)"  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 KtUI(*$`  
        TextBox 220,49,40,21,.TextBox2 'default: 4 ^1BQejD  
    End Dialog ``)ys^V  
    Dim dlg As UserDialog AdesR-e$R  
nKp='>Th  
    ok = Dialog (dlg) ^<'5 V)  
r ioNP(  
    If ok=0 Then    'cancel button was pressed DF-`nD  
        Print "Execution cancelled." OWxYV$  
        End z/)HJo2#  
    End If ]vMr@JM-G  
IExo#\0'6  
    'Assign accommodation and pupil diameter & use defaults if field left empty $*V:;
-H  
    If dlg.TextBox1 = "" Then a?.hvI   
        A = 0           'Default accommodation ykH?;Xu  
    Else k]!Fh^O~,  
        A = CDbl(dlg.TextBox1) ~C6d
5\  
    End If Gy hoo'<  
1hw1AJ}(F  
    If dlg.TextBox2 = "" Then Zj99]4?9  
        pupilDiam = 4   'Default pupil diameter 'due'|#^  
    Else 3k py3z[%  
        pupilDiam = CDbl(dlg.TextBox2) s"#JBw\7  
    End If )Ge.1B$8h  
Mp^%.m  
    Print " " E%t_17,=j  
    Print "Accommodation = " & A & " Diopters" &[f.;1+C  
    Print "Pupil Diameter = " & pupilDiam & " mm" ?D]4*qsIlu  
"ys#%,Z  
    ' Calculate new parameters with accommodation o_p#sdt"  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness  jhjb)r.  
4d#w}  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens Z|K+{{C  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens l69&-Nyg  
JziuwL5,  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens N@lTn}U  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens 9"Oz-!Y4  
k3h
,c;  
    tlens = 3.767 + 0.04*A                  'Lens thickness A9' [x7N  
1{i)7:Y  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction I&?(=i)N  
47.c  
    'Adjust parameters to account for accommodation ]pp
i962Z  
D::$YR ~R  
    '************************************************************************* fCdd,,,}  
    'Aqueous thickness (Position of Lens) 55MrsiW  
    '************************************************************************* la:i!qAH  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) kNP.0  
    GetCustomElement eID, entity 0OO$(R*  
/ PDe<p  
    parID = FindFullName( "Geometry.Arizona Eye" ) bmgK6OyVR  
FtXd6)_S  
    ' Delete any shift(s) in z +ntrp='7O7  
    count = 0 7pMQ1-(  
    While GetOperationCount(eID)>count j&6'sg;n)  
        GetOperation eID, count, op 6FNs4|(
d  
        If op.Type="ShiftZ" Then k~Qb"6n2  
            DeleteOperation eID,count 1t haQ"  
            count=count-1 20750G  
        End If ,S5tkTa  
        count=count+1 H=Rqr  
    Wend GxE"q-G  
VU3xP2c:  
    'Set new shift in @ c,KK~{  
    op.Type = "ShiftZ" NSH20$A<  
    op.val1 = taq >=Hm2daN  
    op.parent = parID 0`.3`Mk   
    AddOperation eID, op y`O !,kW  
    Print "Set aqueous humor thickness = " & taq-0.55 mL/]an@Y  
$Y.Z>I;  
    '************************************************************************* 4lhoA  
    'Radius and conic constant of anterior lens Jlw%t!Kx  
    '************************************************************************* -6a4H?L  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) [~03Z[_"/  
    GetConic eID, entity, curv, conic /+2;".  
u=NpL^6s<  
    SetConic eID, entity, 1/Rant, CCant RzCC>-  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant ,CqJ((  
CA%p^4Q  
    '************************************************************************* eFDhJ  
    'Radius and conic constant of posterior lens .J:04t1  
    '************************************************************************* y+xw`gR:  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) V^fSrW]  
    GetConic eID, entity, curv, conic >^}nk04  
Ncr38~;w  
    SetConic eID, entity, 1/Rpost, CCpost a)J3=Z-  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost 6(Za}H  
+p6cG\Gp  
    '************************************************************************* EH))%LY1y  
    'Lens thickness (Position of posterior lens surface) k$ k/U  
    '************************************************************************* B;Pws$J  

#U45H.Rz  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Q-([3%  
F7$x5h@  
    ' Delete any z-shift(s) N2:};a[ui5  
    count = 0 fFP>$  
    While GetOperationCount(eID)>count \Y.&G,?  
        GetOperation eID, count, op UB[tYZ  
        If op.Type="ShiftZ" Then 3 $7TeqfAC  
            DeleteOperation eID,count fy|ycWW>8  
            count=count-1 .Rt_j  
        End If )6mx\t  
        count=count+1 '5xf?0@s.  
    Wend ?^]29p_  
t}m6];  
    'Set new z-shift ~5Wr |qg%{  
    op.Type = "ShiftZ" P<P4*cOV  
    op.val1 = tlens 7^$PauAv  
    op.parent = parID $nN`K*%  
    AddOperation eID, op KV1zx(WI  
    Print "Set lens thickness = " & tlens w?_y;&sbR  
U-.?+`  
    '************************************************************************* p\lS)9  
    'Lens index of refraction wI'8B{[  
    '************************************************************************* 4T#B7wVoM  
    eID = FindMaterial( "Lens" ) |lH~nU.*  
    GetModelMaterial eID, mat dm3cQ<
0  
ECHl9; +  
    mat.Nd = nlens K"'W4bO#7  
    SetModelMaterial eID, mat OiPE,sv  
    Print "Set lens index of refraction = " & nlens *&p`8:  
""`>v`\  
    '************************************************************************* -$Bom  
    'Pupil diameter AWlR" p2  
    '************************************************************************* w)I!q&`Y  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) \m @8$MK  
:x e/7
-  
    'Adjust pupil diameter (trimming volume inner hole) Bi?.w5  
y[7*^9J  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" Jp)>Wd  
bA]/p%rZ8  
    ' Adjust pupil location to just in front of the lens &.k'Dj2hf  
    parID = FindFullName( "Geometry.Arizona Eye" ) MGn:Gj"d  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) KQsS)ju  
    count = 0 bni :B?#  
    While GetOperationCount(eID)>count Id8^6FLw  
        GetOperation eID, count, op S-^y;#=  
        If op.Type="ShiftZ" Then g Z3VT{  
            DeleteOperation eID,count vn;_|NeSf  
            count=count-1 mo%9UL,#W  
        End If .<JD'%?"  
        count=count+1 R03V+t=  
    Wend {E!"^^0`  
    op.Type = "ShiftZ" 1g`$[wp|  
    op.val1 = taq-0.01 cy=,Dr9O  
    op.parent = parID $-""=O|"  
    AddOperation eID, op ;OW`(jC  
:b+C<Bp64r  
    Print "Set pupil diameter = " & pupilDiam #5HJW[9  
$I(2}u?1+d  
    'Update AZ Eye subassembly Description 9:0JWW^so  
    eID = FindFullName( "Geometry.Arizona Eye" ) <qH>[
\  
    GetEntity eID, entity d!) &@k  
    entity.Description = "Accommodation = " & A & "D" uiq)?XUKv  
    SetEntity eID, entity k,0RpE  
xM85^B'  
    Update 7NG^X"N{Ul  
    Print "DONE!" ^T\JFzV  
     *LJN2;  
End Sub )W9$_<Z  
& i|x2; v  
如果屈光度是4，光瞳直径是4，则会输出如下数据： ~ar8e  
L+Q"z*W  
Accommodation = 4 Diopters jYKs| J)[  
Pupil Diameter = 4 mm btb-MSkO  
Set aqueous humor thickness = 2.81 +) 2c\1  
Set anterior lens radius = 10.4 and conic constant = -2.375869 ^!^8]u<Q  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 +s&+G![  
Set lens thickness = 3.927 (1\!6  
Set lens index of refraction = 1.42672 cw#p!mOi~  
Set pupil diameter = 4 Mj5=
t:MI  
DONE! -)@DH;[tb  
w#_xV =  
.(Q3M0.D  
QQ：2987619807 88Yp0T<1