[分享]Arizona眼睛模型 [复制链接]

简介 |w^nCsv  
2ap0/l[  
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。 v?1xYG@1  
wv
Saq+N  
模型 s2+s1%^Ll  
G5x%:,n  
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。 XAr YmO  
0jwex  
t5za$kW'&  
在FRED中使用0屈光度来创建的，光瞳加在了透镜的前面。材料是创建一个新的材料并选择类型“Model Material”,输入的参数是nd和vd. ~|)'vK8W  
+l$BUX  
光源 ,}#l0BY  
B1gBvss  
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。 3
>sA_  
q:v&wb%  
uod&'g{N  
0~XZ  
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。 ny~~xQ"  
Vz&!N/0i  
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。 q>ps99[=  
Yf(QU`w_  
:u53zX[v  
jkIgEF2d*  
视网膜的散射 p[%FH?  
f~? MNJ2  
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。 DPZG_{3D  
i/UHDqZ  
`H6kC$^Ofx  
E|d 8vt  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 J;g+  
qMe$Qr8  
Bq]eNq  
4HK#]M>yz  
脚本 mMvt#+O  
8FT
hu[  
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： y\&`A:^[ A  
!7-dqw%l  
5}4r'P$m:  
^J]~&.l  
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。 xeX
Pc7JG  
余下的脚本计算与屈光度有关的所有参数。 _0<EbJ8Z  
(TV ye4Z  
分析 qJN2\e2~f  
eZm,K'/!  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ~sSlfQWMzy  
jdGoPa\  
TnqspS2;R  
脚本代码 C<\|4ER
p  
s^b2H !~  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. <OcD[5  
T0ebW w  
Dim entity As T_ENTITY E8~Bp-G)  
Dim op As T_OPERATION Y\len  
Dim mat As T_MODELMATERIAL N(W;(7  
Dim A As Double X99:/3MXB'  
Dim pupilDiam As Double Bp`?inKBOd  
Dim eID As Long K -!YD}OF  
Dim parID As Long &AI/;zru  
Dim count As Integer 1#9Q1@'OS  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double $)M8@d  
Dim tlens As Double, nlens As Double h`OX()N  
Dim curv As Double, conic As Double #AzZ4<;7  
Dim ok As Long eEIa=MB*  
'8v^.gZ  
Sub Main D0D0=s  
([='LyH];z  
    '用户输入对话框 >v9 ("  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 1O0o18'  
        TextBox 220,21,40,21,.TextBox1 'default: 0 7c9-MP)  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 _ a|zvH  
        OKButton 40,91,90,21 t/\J  
        CancelButton 190,91,90,21 N246RV1W  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 @JS O=8  
        TextBox 220,49,40,21,.TextBox2 'default: 4 lz?F ,].  
    End Dialog J)iy6{0"  
    Dim dlg As UserDialog C#`VVtei  
NuKktQd  
    ok = Dialog (dlg) K%ltB&  
, [xDNl[Y|  
    If ok=0 Then    'cancel button was pressed -9)<[>:  
        Print "Execution cancelled." G%w hOIFRq  
        End qr[H0f]  
    End If z^to"j  
ixZ w;+h  
    'Assign accommodation and pupil diameter & use defaults if field left empty Gk0f#;  
    If dlg.TextBox1 = "" Then <GI{`@5C  
        A = 0           'Default accommodation ;H5PiSq;z  
    Else Q<.847 )  
        A = CDbl(dlg.TextBox1) UGK4uK+I`  
    End If tY^MP5*  
[!B($c|\  
    If dlg.TextBox2 = "" Then J fFOU!F\  
        pupilDiam = 4   'Default pupil diameter `VT[YhO#}  
    Else oqa]iBO  
        pupilDiam = CDbl(dlg.TextBox2) ^| L@f  
    End If (5y+g?9d;  
*6oQW  
    Print " " 3A'vq2beM  
    Print "Accommodation = " & A & " Diopters" '`$z!rA  
    Print "Pupil Diameter = " & pupilDiam & " mm" X(nbfh?n  
:uE:mY%R  
    ' Calculate new parameters with accommodation 3[plwe  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness E?1"&D m  
[;3` Aw  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens zWYm*c"n\  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens >6ul\xMU  
.'QE o  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens zi7,?bD  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens n4Od4&r  
Fdsaf[3[v  
    tlens = 3.767 + 0.04*A                  'Lens thickness BFP (2j  

t .*z)N  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction Ffxf!zS  
=~M%zdIXv  
    'Adjust parameters to account for accommodation 5}d"nx  
}!=}g|z#|  
    '************************************************************************* :td#zM  
    'Aqueous thickness (Position of Lens) `NqX{26GV+  
    '************************************************************************* ,f ..46G  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) 0J-]  
    GetCustomElement eID, entity /XtpGk_1)  
PMER~}^  
    parID = FindFullName( "Geometry.Arizona Eye" ) H4[];&]xr  
#w\Bc\  
    ' Delete any shift(s) in z T=6fZ;7  
    count = 0 P%`|Tu!B  
    While GetOperationCount(eID)>count fx&b*OC  
        GetOperation eID, count, op zs!}P  
        If op.Type="ShiftZ" Then |_q:0qo  
            DeleteOperation eID,count bqjj6bf'o  
            count=count-1 HPT{83  
        End If 6(1xU\x  
        count=count+1 f>$Ld1  
    Wend [C)JI;\  
^B[%|{cO  
    'Set new shift in {k.Dy92  
    op.Type = "ShiftZ" @]$qJFXx  
    op.val1 = taq g wM~W  
    op.parent = parID 6*3J3Lc_<  
    AddOperation eID, op ~ KNdV  
    Print "Set aqueous humor thickness = " & taq-0.55 )aY^
k|I  
2,.%]U  
    '************************************************************************* a%f?OsY  
    'Radius and conic constant of anterior lens '_)NI  
    '************************************************************************* {=]1]IWt  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) 8SmtEV[b3  
    GetConic eID, entity, curv, conic =/xTUI4  
P} =eR  
    SetConic eID, entity, 1/Rant, CCant 4j9  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant -oGJPl{r  
2p3ep,  
    '************************************************************************* 3fC|}<Wzt  
    'Radius and conic constant of posterior lens 9y/gW
E  
    '************************************************************************* }2qmL$  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) Wl3jbupu _  
    GetConic eID, entity, curv, conic qkX}pQkG)h  
OE,uw2uaT  
    SetConic eID, entity, 1/Rpost, CCpost V&)lS Qw  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost XAN{uD^3\%  
F$a?} }  
    '************************************************************************* .;6G?8`  
    'Lens thickness (Position of posterior lens surface) nsChNwPX  
    '************************************************************************* YXC?q  
ni @Mqb  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Zkn$D:
 
G/tah@N[7  
    ' Delete any z-shift(s) 4{2)ZI#  
    count = 0 b}P5*}$:9"  
    While GetOperationCount(eID)>count <.c@l,[.z  
        GetOperation eID, count, op 9:tvkl  
        If op.Type="ShiftZ" Then .:eNL]2%:  
            DeleteOperation eID,count ~z''kH=e  
            count=count-1 ,,+ ~./)  
        End If Z Mp  
        count=count+1 _E({!t"`  
    Wend :UuPy|>  
;1Kxqpz_i  
    'Set new z-shift i*16kdI.  
    op.Type = "ShiftZ" 5gpqN)|)[  
    op.val1 = tlens F">>,Oc)U"  
    op.parent = parID .HTX7mA3  
    AddOperation eID, op t(SSrM]  
    Print "Set lens thickness = " & tlens #A|~s;s>N  
~<0!sE&y  
    '************************************************************************* 7h?yAgDv~  
    'Lens index of refraction I+ipTeB^  
    '************************************************************************* ,6[}qw)*  
    eID = FindMaterial( "Lens" ) m.~&n!1W*`  
    GetModelMaterial eID, mat ;]<{<czc  
PPCZT3c=  
    mat.Nd = nlens q9n0bw^N  
    SetModelMaterial eID, mat wEK@B&DV  
    Print "Set lens index of refraction = " & nlens .ON+ ( #n  
*qcL(] Yq  
    '************************************************************************* U:]b
&I  
    'Pupil diameter yV
PkJ  
    '************************************************************************* \F
OX#|i)  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) s)]Z*#ZZ  
cK.T=7T  
    'Adjust pupil diameter (trimming volume inner hole) UXB[3SP  
SU, t,i  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" I>b-w;cC  
)2X ng_,  
    ' Adjust pupil location to just in front of the lens g{8R+  
    parID = FindFullName( "Geometry.Arizona Eye" ) x{io*sY-  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" )
zE VJ  
    count = 0 QjfQoT F  
    While GetOperationCount(eID)>count n3{m "h3  
        GetOperation eID, count, op P=&Je?  
        If op.Type="ShiftZ" Then (sw1HR  
            DeleteOperation eID,count "m]"%MU78  
            count=count-1 t"1'B!4  
        End If $;*YdZ`q  
        count=count+1 G)l[\6Dn  
    Wend o"^}2^)_SR  
    op.Type = "ShiftZ" zx\N^R;Jq  
    op.val1 = taq-0.01 )@Yp;=l  
    op.parent = parID 
qR<  
    AddOperation eID, op amf=uysr  
{+[~;ISL  
    Print "Set pupil diameter = " & pupilDiam =$5[uI2  
uPe4Rr  
    'Update AZ Eye subassembly Description &sL5Pt_  
    eID = FindFullName( "Geometry.Arizona Eye" ) wxZnuCO%H8  
    GetEntity eID, entity lwLK#_5u  
    entity.Description = "Accommodation = " & A & "D" yz-IZt(  
    SetEntity eID, entity !)tXN=(1a  
6<H[1PI`,G  
    Update ,TU!W|($  
    Print "DONE!" 9#%(%s2+  
     +7<{yP6wU  
End Sub XzQ=8r>l  
:EyH'v  
如果屈光度是4，光瞳直径是4，则会输出如下数据： :5?ti  
>c7/E  
Accommodation = 4 Diopters ac.O#6&  
Pupil Diameter = 4 mm #I@]8U#,":  
Set aqueous humor thickness = 2.81 l3}n.ODA  
Set anterior lens radius = 10.4 and conic constant = -2.375869 i`r,B`V`08  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 "}K/ b  
Set lens thickness = 3.927 k`js~/Xv  
Set lens index of refraction = 1.42672
+nd'Uf   
Set pupil diameter = 4 17{]QuqNF  
DONE! :=~%&  
W<2%J)N<  
cFUYT$8>  
QQ：2987619807 ?9
vBn