[分享]Arizona眼睛模型 [复制链接]

简介 tWy0% -  
>AI65g  
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]@5M  
$TS4YaJ%  
模型 +]P??`,R;  
Z}6
  
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。 nn!W-Bsqjh  
=n|n%N4Y  
S,,,D+4  
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. )e`$'y@L$  
(<!Yw|~  
光源 :G\f(2@  
"b
5:6\  
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。 }S|~^  
P 0v&*y3Y  
'=}F}[d"kk  
'N#,,d/G  
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。 qg
6283'?  
ib8@U}Vn1  
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。 5>M6lwS  
i
bo{!>m  
v8Gm;~  
/f2HZfj  
视网膜的散射 4sOo>.<x  
X;/~d>@  
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。 70IBE[T&  
|c,,*^  
C,$$bmS=  
HC4qP9Gs  
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。 _GSl}\  
f&x7g.I  
_Eo$V&  
G*.}EoA  
脚本 {1a%CsCM  
HAJK%zLc  
内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： KneCMFy  
;s m )f  
]
Q-*xho  
?QuD:vck  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 4 0as7.q  
余下的脚本计算与屈光度有关的所有参数。 1#BMc%  
;Gf,$dbWn  
分析 @ov*Fh  
^i>Tm9vM  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 t;g=@o9YA  
z2:^Qg  
>p"ytRu^  
脚本代码 LDilrG)  
V80BO#Pk  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. @,btQ_'X  
"`;$wA  
Dim entity As T_ENTITY K)!yOa'fH  
Dim op As T_OPERATION i}d^a28  
Dim mat As T_MODELMATERIAL 7OSk0%Q,  
Dim A As Double };{V]f 0  
Dim pupilDiam As Double Lh eOGM  
Dim eID As Long P_Rh& gkuK  
Dim parID As Long 7{0;<@  
Dim count As Integer [N]5)n  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double iKs @oHW  
Dim tlens As Double, nlens As Double NrQGoAOw  
Dim curv As Double, conic As Double Ll4/P[7:?  
Dim ok As Long "N'|N.,  
O"%b@$p\L  
Sub Main xw[KP [(  
]Dj,8tf`H  
    '用户输入对话框 {,V.IDs8[  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ,ddoI
I  
        TextBox 220,21,40,21,.TextBox1 'default: 0 _Z9H
Ol@  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 t]dtBt].:  
        OKButton 40,91,90,21 v D"4aw  
        CancelButton 190,91,90,21 ~cC=DeX  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 B4fMD]  
        TextBox 220,49,40,21,.TextBox2 'default: 4 2VB|a;Mo  
    End Dialog +hoZW R  
    Dim dlg As UserDialog {, +,:w7  
'IVNqfC)u  
    ok = Dialog (dlg) 8OV;&Z,x  
K=S-p3\g  
    If ok=0 Then    'cancel button was pressed 7sgK+ ip  
        Print "Execution cancelled." X*4iNyIs_  
        End #Tm^$\*h\]  
    End If =t@8Y`9w  
F@4TD]E0^  
    'Assign accommodation and pupil diameter & use defaults if field left empty {Y0Uln5u  
    If dlg.TextBox1 = "" Then 1u9*)w  
        A = 0           'Default accommodation =x_~7 Xc{  
    Else IF>dsAAI<  
        A = CDbl(dlg.TextBox1) Vn7
FbaO^  
    End If aRt`IcZYz  
-XuRQ_)nG  
    If dlg.TextBox2 = "" Then 6!QY)H^j9,  
        pupilDiam = 4   'Default pupil diameter uD'GI  
    Else AbqeZn  
        pupilDiam = CDbl(dlg.TextBox2) 8ch^e[U`  
    End If [unK5l4_!  
\ytF@"7  
    Print " " KR49Y>s<  
    Print "Accommodation = " & A & " Diopters" `jI$>{oa  
    Print "Pupil Diameter = " & pupilDiam & " mm" cN{(XmX5n  
q3_ceXYU  
    ' Calculate new parameters with accommodation WUN|,P`b  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness XA1gV>SJ  
@2X{e7+D  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens [5"F=tT7WP  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens AlVBhR`  
>14x.c  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Z?@oe-mz  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens i(hL6DLD  
F4b$  
    tlens = 3.767 + 0.04*A                  'Lens thickness n7>L&?N#y#  
F{'lF^Dc  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction  K}OY!|  
9 SBVp6'  
    'Adjust parameters to account for accommodation ;A\SbLM  
Yg~$1b@  
    '************************************************************************* y\C_HCU H  
    'Aqueous thickness (Position of Lens) W Z_yaG$U  
    '************************************************************************* uOv0ut\\G  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) F5+)=P#  
    GetCustomElement eID, entity VhfMj|  
'ZiTjv]  
    parID = FindFullName( "Geometry.Arizona Eye" ) CGp7 Tx#  
_U<r@  
    ' Delete any shift(s) in z Wcf;ZX
  
    count = 0 JtbwY@R  
    While GetOperationCount(eID)>count nf2[hx@=U  
        GetOperation eID, count, op @dHQ}Ni  
        If op.Type="ShiftZ" Then "NMSLqO  
            DeleteOperation eID,count N!Cy)HnS\w  
            count=count-1 YD@n8?~$$  
        End If ],l}J'.8<V  
        count=count+1 6!|/(~  
    Wend i^Ip+J+[  
a0
/[L  
    'Set new shift in d95 $w8>  
    op.Type = "ShiftZ" -|WQs'%O  
    op.val1 = taq {kdS t1  
    op.parent = parID `JZ`j7f  
    AddOperation eID, op (j%;)PTe+&  
    Print "Set aqueous humor thickness = " & taq-0.55 $:u5XJx  
nvOJY6)$V  
    '************************************************************************* ZDl6F`  
    'Radius and conic constant of anterior lens ^!j,d_)b!  
    '************************************************************************* c*N>7IF,  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) H3Zsm)+:  
    GetConic eID, entity, curv, conic Fs 95^T  
(DTXc2)c  
    SetConic eID, entity, 1/Rant, CCant lWRRB&8  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant 6^#@y|.  
TJ`Jqnh  
    '************************************************************************* [:"7B&&A  
    'Radius and conic constant of posterior lens tvEf-z  
    '************************************************************************* ,+U,(P5>s  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Ra-%,cS  
    GetConic eID, entity, curv, conic M\L^ Wf9  
T8US` MZ  
    SetConic eID, entity, 1/Rpost, CCpost 56l1&hp8In  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost %]\IC(q  
G5hh$Nmpi  
    '************************************************************************* %7[Z/U=  
    'Lens thickness (Position of posterior lens surface) 4lsg%b6_%,  
    '************************************************************************* grbUR)f<?-  
sF!nSr  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) >oasA2S  
P;DGs]PF  
    ' Delete any z-shift(s)  WgayH  
    count = 0 "qxu9Hg!  
    While GetOperationCount(eID)>count N799@:.  
        GetOperation eID, count, op  M_ii  
        If op.Type="ShiftZ" Then a%N
SL6  
            DeleteOperation eID,count m6iQB\ \  
            count=count-1 %DIZgPd\  
        End If k]] e8>  
        count=count+1 |4?O4QN
 
    Wend Fo$'*(i  
)|Xi:Zd5>  
    'Set new z-shift p)y'a+|7  
    op.Type = "ShiftZ" E(/M?>t-  
    op.val1 = tlens se]q~<&  
    op.parent = parID ]<g`rR
7}  
    AddOperation eID, op
#z&@f  
    Print "Set lens thickness = " & tlens fXfO9{E  
)DwHLaLW  
    '************************************************************************* IuN:*P  
    'Lens index of refraction c@<vFoq  
    '************************************************************************* :o=a@Rqx  
    eID = FindMaterial( "Lens" ) H
COE'24I  
    GetModelMaterial eID, mat )D>= \Me  
&vHfuM`  
    mat.Nd = nlens S*9qpes-m|  
    SetModelMaterial eID, mat Kjfpq!NYE  
    Print "Set lens index of refraction = " & nlens ReZ&SNJ  
V0)F/qY  
    '************************************************************************* ~uRL+<.c  
    'Pupil diameter r.#"he_6!.  
    '************************************************************************* k%2Rv4)hU  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) = k7}[!T  
i?D KKjN$  
    'Adjust pupil diameter (trimming volume inner hole) a
i@hQJ*  
'pQ\BH  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" b@?pofZ`k  
V+- ]txu|  
    ' Adjust pupil location to just in front of the lens ,[{Z_co  
    parID = FindFullName( "Geometry.Arizona Eye" ) p"k[ac{  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) ^Z`?mNq9  
    count = 0 Qk h}=3u  
    While GetOperationCount(eID)>count XJ{b_h#N  
        GetOperation eID, count, op -er8(snDQ  
        If op.Type="ShiftZ" Then 'BmLR{[2L  
            DeleteOperation eID,count e=#'rDm  
            count=count-1 i3v|r 0O~L  
        End If W&H
F*Aw  
        count=count+1 ]46#u=y~3  
    Wend X\ bXat+  
    op.Type = "ShiftZ" c D0-g=&   
    op.val1 = taq-0.01 s?pd&_kOv3  
    op.parent = parID K%
iA-h  
    AddOperation eID, op 2SHS!6
:Rl  
=&YhA}l\O  
    Print "Set pupil diameter = " & pupilDiam sBV})8]KM  
{IR-g,B  
    'Update AZ Eye subassembly Description 71(C@/J  
    eID = FindFullName( "Geometry.Arizona Eye" ) RhQ[hI  
    GetEntity eID, entity T=D|jt  
    entity.Description = "Accommodation = " & A & "D" Gr}lr gPS  
    SetEntity eID, entity c3]X#Qa#m$  
5*P+c(=  
    Update
0kOl,%Ey  
    Print "DONE!" DSX.84  
     OD~B2MpM>  
End Sub C]'ru  
N`1W"Rx!  
如果屈光度是4，光瞳直径是4，则会输出如下数据： 8{ooLdpX7  
g*%z{w  
Accommodation = 4 Diopters
f tE2@}  
Pupil Diameter = 4 mm =/zb$d cz  
Set aqueous humor thickness = 2.81 _dk/SWb)  
Set anterior lens radius = 10.4 and conic constant = -2.375869 k
3S  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 P<s0f:".  
Set lens thickness = 3.927 lU&[){  
Set lens index of refraction = 1.42672 ;I@@PUnR  
Set pupil diameter = 4 ~+OAAkJ9  
DONE! ZA{T0:  
\Jy/ a-  
b`yb{& ,?  
QQ：2987619807 Lw_s'QNWR