[分享]Arizona眼睛模型 [复制链接]

简介 hHXTSk2  
3pQ^vbQ"  
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。 ]H[%PQ r`Z  
JSKAlw  
模型 xn1=@0 a  
-bJC+Yn  
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。 Mzfuthq=@  
yex4A)n9"'  
oY;=$8y<q  
在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. P[q`{TdV  
ZP*(ZU@j=Z  
光源 a
J;6!WFW  
w+MCOAB  
多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 c
Hr.7 w  
Wbra*LNU  
~m0l_:SF  
`)Z+]5:  
除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 %p wpRD@  
;~nz%LJ  
在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 P/9iB/  
xNLvK:@0p  
"V7 SB   
-hn~-Sy+  
视网膜的散射 
e3YdHp  
6B pm+}  
在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 i7
*cpNPO  
E 0k1yA  
gJkvH[hDY  
Qx{[#[Da  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 o>G^)aRa  
IJnh@?BC  
~4MUac^w  
'5:P,1tWU  
脚本 Td|x~mZv:  
uoX] #<1J  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： Gd=l{
~  
#"3az8u  
+[2X@J  
J3;dRW  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 0SJ7Q
Ro|K  
余下的脚本计算与屈光度有关的所有参数。 "@h 5 SF  
\Gzo^w  
分析 ?M02|8-  
[p 6#fG *  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 3aK/5)4|B  
71$MhPvd<  
jT6zpi~]E  
脚本代码 slV7,4S&!  
MZ/PXY  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. x?|C-v  
+ISXyGu  
Dim entity As T_ENTITY lMcSe8LBQa  
Dim op As T_OPERATION .JJ^w!|>#  
Dim mat As T_MODELMATERIAL xUG:x4Gz+  
Dim A As Double TAXl73j_CY  
Dim pupilDiam As Double #_zd`s3k  
Dim eID As Long ;4g_~fB  
Dim parID As Long l:Y$A$W]>  
Dim count As Integer |>Xw"]b;  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double @|2}*_3\  
Dim tlens As Double, nlens As Double tFYIKiq2  
Dim curv As Double, conic As Double fK$N|r  
Dim ok As Long 0lvX,78G;  
zF F=v7[j  
Sub Main "eH~/6A  
JW5SBt>  
    '用户输入对话框 BhMHT:m  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 )kE(%q:*P$  
        TextBox 220,21,40,21,.TextBox1 'default: 0 bnWKfz5  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 T21SuM  
        OKButton 40,91,90,21 K%p*:P  
        CancelButton 190,91,90,21 vG
k}r  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 yL&_>cV  
        TextBox 220,49,40,21,.TextBox2 'default: 4 HxVQeyOR  
    End Dialog K7x,>  
    Dim dlg As UserDialog 7 %P?3  
,u,]ab  
    ok = Dialog (dlg) UJ0Dy` f  
R.g'&_zx  
    If ok=0 Then    'cancel button was pressed B) 81mcy  
        Print "Execution cancelled." N1V qK  
        End ;5*)kX  
    End If ?gSk%]S/!  
:*2+t-  
    'Assign accommodation and pupil diameter & use defaults if field left empty 3xW;qNj:!l  
    If dlg.TextBox1 = "" Then LRhq%7p7  
        A = 0           'Default accommodation Y=gj{]4  
    Else !n`ogzOh  
        A = CDbl(dlg.TextBox1) #0-!P+c[  
    End If !(!BW9Zt+  
X-Sso9/q.  
    If dlg.TextBox2 = "" Then t;DZ^Z"{  
        pupilDiam = 4   'Default pupil diameter cZRLYOC  
    Else {C%/>e2-%  
        pupilDiam = CDbl(dlg.TextBox2) 1%L* 9>e  
    End If ;z9(  
5k`[a93T  
    Print " " !U"1ZsO)l  
    Print "Accommodation = " & A & " Diopters" J3sO%4sYR  
    Print "Pupil Diameter = " & pupilDiam & " mm" ksxacRA7\  
ta+'*@V+G  
    ' Calculate new parameters with accommodation Q#@gOn=W\  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 6TE RQ  
}lgqRg)F9[  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens }P$48o VY  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens yaf&SR@7k{  
O_f|R1G5z  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens NgKbf vt  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens AJrwl^lm  
4/{Io &|  
    tlens = 3.767 + 0.04*A                  'Lens thickness ^uW!=%D  
S^
?OKqS  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction LnJ/t(KV  
y+RT[*bX5o  
    'Adjust parameters to account for accommodation y(:hN)  
>GiM?*cC  
    '************************************************************************* JF*JFOb  
    'Aqueous thickness (Position of Lens) laM0W5  
    '************************************************************************* k=[!{I  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) "F+ 9xf&r  
    GetCustomElement eID, entity )o[ O%b  
KQ/v](
77  
    parID = FindFullName( "Geometry.Arizona Eye" ) E{r_CR+8  
VEd#LSh  
    ' Delete any shift(s) in z oll~|J^sg  
    count = 0 Sv-}w$  
    While GetOperationCount(eID)>count FTt7o'U  
        GetOperation eID, count, op Iz
2K  
        If op.Type="ShiftZ" Then QEM")(  
            DeleteOperation eID,count q*A2>0O  
            count=count-1 -e%=Mpq.  
        End If vj
J!d#8  
        count=count+1 dUn8Xqj1  
    Wend i^uC4S~  
f?F i{m  
    'Set new shift in o lNL|WJ`w  
    op.Type = "ShiftZ" >"F~%D<.  
    op.val1 = taq }se)=7d8 Z  
    op.parent = parID w\_NrsO!x  
    AddOperation eID, op *6Rl[eXS  
    Print "Set aqueous humor thickness = " & taq-0.55 >w9)c|  
PpGNA  
    '************************************************************************* $BE^'5G&4Y  
    'Radius and conic constant of anterior lens
g_] u<8&  
    '************************************************************************* K 3&MR=#^  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) /[[zAq{OA  
    GetConic eID, entity, curv, conic "h7-nwm  
;sNyN#  
    SetConic eID, entity, 1/Rant, CCant PZpwi?N  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant c6s(f  
S:vv*5  
    '************************************************************************* HtEjM|zj  
    'Radius and conic constant of posterior lens N) 
{  
    '************************************************************************* *^c4q|G.-  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) qB]z"Hfq,  
    GetConic eID, entity, curv, conic $Miii`VS9  
]Nt97eD
)  
    SetConic eID, entity, 1/Rpost, CCpost W\U zw,vI  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost yixW>W}  
ynM{hN.+H  
    '************************************************************************* 5v
bnO]8  
    'Lens thickness (Position of posterior lens surface) K;6K!6J:[  
    '************************************************************************* "MC&!AMv  
'QT(TF>  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) qvYY
Ku  
M=o,Sav5*  
    ' Delete any z-shift(s) 9aZ3W<N`M  
    count = 0 92Ar0j]  
    While GetOperationCount(eID)>count H gNUr5p  
        GetOperation eID, count, op Yc?taL)  
        If op.Type="ShiftZ" Then #A]7cMZ'W  
            DeleteOperation eID,count  Kz3u  
            count=count-1 |,dMF2ADc  
        End If QJdSNkc6  
        count=count+1 @aCg1Rm  
    Wend {K3\S 0L  
 TWx<)  
    'Set new z-shift a2=wJhk  
    op.Type = "ShiftZ" GetUCb%1  
    op.val1 = tlens =#Vdz=.  
    op.parent = parID nQ$N(2<Fe  
    AddOperation eID, op ;S?1E
:\av  
    Print "Set lens thickness = " & tlens kP;:s  
:jp?FF^j;  
    '************************************************************************* aGpRdF1;!  
    'Lens index of refraction >j`*-(`2fa  
    '************************************************************************* & p_;&P_  
    eID = FindMaterial( "Lens" ) i6`8yw  
    GetModelMaterial eID, mat @%\ANM$S  
{]D!@87  
    mat.Nd = nlens oN `tZ;a  
    SetModelMaterial eID, mat 34;c0
0  
    Print "Set lens index of refraction = " & nlens g=U?{<8.m  
7vj[ AOq3l  
    '************************************************************************* ljt1:@SN(  
    'Pupil diameter cC}s
5`  
    '************************************************************************* uhc0,V;S  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) r]HLO'<]  
YSa:"A  
    'Adjust pupil diameter (trimming volume inner hole) *?K`T^LS  
iBo-ANnK9  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" lZ)u4_  
|%RFXkHS  
    ' Adjust pupil location to just in front of the lens ~-:CN(U  
    parID = FindFullName( "Geometry.Arizona Eye" ) LWQ BGiJj  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) 0a'@J~v!  
    count = 0 :X4\4B*~  
    While GetOperationCount(eID)>count }SN'*w@E  
        GetOperation eID, count, op 'h= >ej*  
        If op.Type="ShiftZ" Then iMA)(ZS  
            DeleteOperation eID,count _r8AO>  
            count=count-1 qyJpm{  
        End If Bp/8 >EO`  
        count=count+1 \FKIEg+(2  
    Wend vy#c(:UQR  
    op.Type = "ShiftZ" Y4714  
    op.val1 = taq-0.01 njq-
iU  
    op.parent = parID sQ)4kF&,  
    AddOperation eID, op I9Sh~vTm=u  
ix#  
    Print "Set pupil diameter = " & pupilDiam KdR&OBm  
kW:!$MX!  
    'Update AZ Eye subassembly Description }jk^M|Z"Oz  
    eID = FindFullName( "Geometry.Arizona Eye" ) 4xYo2X,B  
    GetEntity eID, entity zp9 ?Ia  
    entity.Description = "Accommodation = " & A & "D" Wey\GQ`"8  
    SetEntity eID, entity A!Yqj~  
5:PZ=jPR  
    Update d:wAI|  
    Print "DONE!" 5-3gsy/Mo  
     $U0(%lIU  
End Sub A+
}4N%kh  
_0f[.vN  
如果屈光度是4，光瞳直径是4，则会输出如下数据： 3PEs$m9e  
 WcJ{}V9  
Accommodation = 4 Diopters Grub1=6l  
Pupil Diameter = 4 mm vOj$-A--qU  
Set aqueous humor thickness = 2.81 Hb$q}1+y  
Set anterior lens radius = 10.4 and conic constant = -2.375869 5;Z~+$1  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 $_ i41f[  
Set lens thickness = 3.927 W&Hf}q
s  
Set lens index of refraction = 1.42672 zSH#j RDV  
Set pupil diameter = 4 [<`+9R  
DONE! 37[C^R!1c  
0IdD  
WE"'3u
^k  
QQ：2987619807 y5ExEXa