[转载]FRED运用：Arizona眼睛模型 [复制链接]

简介 ~afg)[(  
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。 n4lutnF  
Blq8H"3!:  
模型 Zf7&._y.  
/*Qq[C  
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。 'Peni1_  
5'a3huRtV  
fSDi-I  
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. s_.]4bl.8  
8.bKb<y  
光源 +h_ !0dG  
6!^[];%xN  
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。 wM[~2C=vx  
G|8%qd  
)bx_;9Y{  
_tr<}PnZ  
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。 A8A~!2V  
3sCFHn#c  
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!,<@b)  
A[WV'!A,  
%r)avI  
L!_ZY  
视网膜的散射 1{_A:<VBl  
H UoyLy  
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。 >!6i3E^  
4x%(9_8{-  
2FD=lR?6  
4(l?uU$  
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。 u9=SpgB#  
l<(Y_PE:  
`bKA+c,f  
<\zCpkZ'B  
脚本 ZDL']*)'  
xyr+_k-x&q  
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： TO,rxf  
X}P$emr7  
c.\O/N   
|_u8mV  
如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 *]JdHO  
余下的脚本计算与屈光度有关的所有参数。 UueD
(T;p  
l!E7AKk8  
分析 AGA`fRVx  
<ktzT&A  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 Fyyg`J  
/9yaW7w  
,D6v4<jh  
脚本代码 nxQ?bk}*d  
t]1ubt2W  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. U-wLt(Y<  
b{DiM098  
Dim entity As T_ENTITY sM1RU  
Dim op As T_OPERATION h?\2_s  
Dim mat As T_MODELMATERIAL `nR%Cav,U  
Dim A As Double ?j7vZ}iRi  
Dim pupilDiam As Double cD1o"bq  
Dim eID As Long &@"]+33  
Dim parID As Long k&hc m  
Dim count As Integer !0/z>#b  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double y%]8'q$  
Dim tlens As Double, nlens As Double .'[/|4H  
Dim curv As Double, conic As Double v;y0jD
#b  
Dim ok As Long ~fz[x9\  
{mE! Vf  
Sub Main &Y@#g9G  
U3vEdw<lV  
    '用户输入对话框 puJ#w1!x`  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 P];JKE%  
        TextBox 220,21,40,21,.TextBox1 'default: 0 0@1:M  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 ~$O1`IT  
        OKButton 40,91,90,21 c.H?4j7ga  
        CancelButton 190,91,90,21 WKA'=,`v  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 @E`?<|B}  
        TextBox 220,49,40,21,.TextBox2 'default: 4 i`%
.  
    End Dialog `29TY&p+"  
    Dim dlg As UserDialog \o3"~\|6C  
$mco0%$  
    ok = Dialog (dlg) iZ[tHw||  
BH0!6Oq  
    If ok=0 Then    'cancel button was pressed %R0v5=2'  
        Print "Execution cancelled." guN4-gGDr<  
        End #:3r4J%+~  
    End If gvli%9n  
FYPz 4K  
    'Assign accommodation and pupil diameter & use defaults if field left empty }wt%1v-10U  
    If dlg.TextBox1 = "" Then ZofHic  
        A = 0           'Default accommodation v@ONo?)  
    Else P`s(kIe  
        A = CDbl(dlg.TextBox1) .")b?#K  
    End If (0*v*kYdL+  
'zSgCgCHX8  
    If dlg.TextBox2 = "" Then UPCQs",  
        pupilDiam = 4   'Default pupil diameter i8V0Ty4~N  
    Else ].DY"  
        pupilDiam = CDbl(dlg.TextBox2) yYAnwf  
    End If ` DCU>bt&R  
%u]6KrG18b  
    Print " " si/er"&o  
    Print "Accommodation = " & A & " Diopters" eFQQW`J  
    Print "Pupil Diameter = " & pupilDiam & " mm" l%"`{   
*)VAaGUX>  
    ' Calculate new parameters with accommodation cV$lobqO  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness 3\!F\tqD \  
;cSGlE
|  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens q G;-o)h  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens *d*oS7  
2o{@nN8%  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens
.A<sr  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens e&J3N  
4e%8D`/=M  
    tlens = 3.767 + 0.04*A                  'Lens thickness 6zYaA  
i^%-aBZ  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction X7cWgo66T  
c
qQRU  
    'Adjust parameters to account for accommodation IlHY%8F{  
2:J,2=%  
    '************************************************************************* 9={N4}<  
    'Aqueous thickness (Position of Lens) u7k|7e=xk  
    '************************************************************************* RebTg1vGu  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) #4y,a_)  
    GetCustomElement eID, entity {;RF  
D3?N
<9g  
    parID = FindFullName( "Geometry.Arizona Eye" ) GJak.,0t  
_'JRo%{xGX  
    ' Delete any shift(s) in z J/S{FxNe]  
    count = 0 ltEF:{mLe#  
    While GetOperationCount(eID)>count R#0{Wg0O)  
        GetOperation eID, count, op )Xno|$b5Eo  
        If op.Type="ShiftZ" Then Pf8u/?/  
            DeleteOperation eID,count :o\5K2]:  
            count=count-1 <ZrFOb  
        End If %8Yyj{^!(  
        count=count+1 P0#`anUr1  
    Wend vvh.@f  
qz:]-A  
    'Set new shift in Iq,v  
    op.Type = "ShiftZ" }J;~P 9Y  
    op.val1 = taq i`~~+6`J  
    op.parent = parID .}p|`3$P  
    AddOperation eID, op )VY10R)$  
    Print "Set aqueous humor thickness = " & taq-0.55 !QTPWA  
,I39&;Iq  
    '************************************************************************* R92R}=G!  
    'Radius and conic constant of anterior lens G;2[  
    '************************************************************************* %^')G+>i  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) e`ex]py<C  
    GetConic eID, entity, curv, conic "UpOY  
6h@+?{F.  
    SetConic eID, entity, 1/Rant, CCant $NCm;0\B|  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant  QT_^M1%  
S>EDL  
    '************************************************************************* 8bbVbP  
    'Radius and conic constant of posterior lens ^N{X"  
    '************************************************************************* cyb(\ fsC  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) qvN"1=nJ  
    GetConic eID, entity, curv, conic x:C@)CAr  
-R74/GBg  
    SetConic eID, entity, 1/Rpost, CCpost \P?--AIq<  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost FoLDMx(  
=SL^>HS.fo  
    '************************************************************************* HqRCjD  
    'Lens thickness (Position of posterior lens surface) D8 wG!X  
    '************************************************************************* GDmv0V$6  
Xr2 Wa  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) `OLB';D  
fU`T\  
    ' Delete any z-shift(s) C,3T!\  
    count = 0 6>lW5U^yA\  
    While GetOperationCount(eID)>count XJ\_V[WA  
        GetOperation eID, count, op "Y(%oJS]D  
        If op.Type="ShiftZ" Then No~6s.H  
            DeleteOperation eID,count p`LL   
            count=count-1 sOC| B  
        End If _]_LF[  
        count=count+1 d~,n_E$q;  
    Wend kw;wlFU;  
v'$ykZ!Z  
    'Set new z-shift YiO3<}Uf  
    op.Type = "ShiftZ" $4:~*IQ  
    op.val1 = tlens
X;5S  
    op.parent = parID H<{*ub4'L*  
    AddOperation eID, op b2W;|  
    Print "Set lens thickness = " & tlens "|\94  

qWkx:-g]  
    '************************************************************************* 
CCy.  
    'Lens index of refraction lvG3<ls0K$  
    '************************************************************************* 2t.fD@  
    eID = FindMaterial( "Lens" ) qm~Kw!kV  
    GetModelMaterial eID, mat 0x6@{0  
 @}Pw0vC  
    mat.Nd = nlens }0krSzcn#,  
    SetModelMaterial eID, mat |})rt5|f1!  
    Print "Set lens index of refraction = " & nlens tPA"lBS !  
VJGwd`qo*A  
    '************************************************************************* }el,^~  
    'Pupil diameter cx<h_  
    '************************************************************************* <)"iL4 kDI  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) ^=3 ^HQ'Zm  
A03I-^0g+  
    'Adjust pupil diameter (trimming volume inner hole) ~LSy7$rz  
p+!f(H  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" <'VA=orD  
&(Go
pWR`e  
    ' Adjust pupil location to just in front of the lens =:kiSrBS3t  
    parID = FindFullName( "Geometry.Arizona Eye" ) D_zcOq9  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) kK08W3@&t  
    count = 0 yFIl^Ck%  
    While GetOperationCount(eID)>count N" 8*FiZ|  
        GetOperation eID, count, op '! #On/  
        If op.Type="ShiftZ" Then 7ucx6J]c  
            DeleteOperation eID,count 6 bYC  
            count=count-1 p^}L  
        End If @^BS#  
        count=count+1 lrq>TJEcx  
    Wend ^V_ku@DY  
    op.Type = "ShiftZ" 4,o %e,z  
    op.val1 = taq-0.01 oA5<[&~<  
    op.parent = parID ;B,nzx(L  
    AddOperation eID, op N;e}dwh&  
D<lQoO+  
    Print "Set pupil diameter = " & pupilDiam tuX =o  
U;^CU!a  
    'Update AZ Eye subassembly Description J{aQ1)  
    eID = FindFullName( "Geometry.Arizona Eye" ) YWybPD4\(  
    GetEntity eID, entity tj`tLYOZ@-  
    entity.Description = "Accommodation = " & A & "D" >|y>e{P  
    SetEntity eID, entity "v*oga%  
9(i0"hS^  
    Update mYzsTUq  
    Print "DONE!" eV@4VxaZ  
     W*1d X"S  
End Sub $K5ni{M;  
9[6G8;<D&  
如果屈光度是4，光瞳直径是4，则会输出如下数据： @&/s~3  
<>ZBW9  
Accommodation = 4 Diopters DKe6?PG  
Pupil Diameter = 4 mm ^Tb}]aHg  
Set aqueous humor thickness = 2.81 $w 5#2Za  
Set anterior lens radius = 10.4 and conic constant = -2.375869 V,99N'o~x  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 "H wVK  
Set lens thickness = 3.927 ,<R>Hiwg/s  
Set lens index of refraction = 1.42672 |?4~T:  
Set pupil diameter = 4 Nv}U/$$S  
DONE! Uqb
]e?@  
P]~N-xdV