[分享]Arizona眼睛模型 [复制链接]

简介 :zbQD8jv  
P{jbl!UD7  
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。 [`[|l  
Beo@K|3GN  
模型 _
pG-
qK  
t+G#{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。 mb3"U"ohs  
IGQFtO/x  
yNo0ubY  
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. rJTa  
@)M9IOR  
光源 eA?RK.e  
>dD@j:Qc  
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。 FUb\e-Q=  
nEy&>z  
X-Kh(Z  
<w9JRpFY  
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。 B{#I:Rs9  
7"x;~X  
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。 T2W eE@o  
|F[+k e  
h"Q8b}$^)  
iC~^)-~H=w  
视网膜的散射 {duz\k2  
3M7/?TMw{6  
在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 fOGFq1
D  
itP,\k7>d  
lNh70G8^p  
 'KL0@l  
注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 JR21>;l#2  
@n /nH?L  
eJ-xsH*8  
-3*]G^y2  
脚本 #q$HQ&k  
SHgN~Um  
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： FVbb2Y?R  
!i}w~U<  
_6hQ %hv8  
I;(L%TT `  
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。 BwpqNQN  
余下的脚本计算与屈光度有关的所有参数。 @*XV`_!h  
?e4YGOe.  
分析 _D&598xx  
-d/ =5yxL  
屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 +@f26O7$*  
G>}255qY  
X`K<>0.N  
脚本代码 o:'MpKm  
ET*SB  
Option Explicit     'Remove this to enable non-dimensioned variables to be used. )2o?#8J  
J]'zIOQ  
Dim entity As T_ENTITY +3BN}  
Dim op As T_OPERATION |YWD8 +  
Dim mat As T_MODELMATERIAL G~a ZJ,  
Dim A As Double JXQO~zj  
Dim pupilDiam As Double YkSl^j[DHs  
Dim eID As Long t{9GVLZ  
Dim parID As Long vI>w e  
Dim count As Integer V f&zL Sgr  
Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double _jVN&\A]mC  
Dim tlens As Double, nlens As Double (%6P0*  
Dim curv As Double, conic As Double 9$
w.9`Py  
Dim ok As Long 5C]x!>kX  
~ .g@hS8>  
Sub Main 1CZgb  
"&u@d~`-n  
    '用户输入对话框 ]%H`_8<gc  
    Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 ]_gU#,8  
        TextBox 220,21,40,21,.TextBox1 'default: 0 U7F!Z( 9  
        Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 tcI*a>  
        OKButton 40,91,90,21 !e<^? r4  
        CancelButton 190,91,90,21 vvMT}-!  
        Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 UI0VtR]   
        TextBox 220,49,40,21,.TextBox2 'default: 4 2%m BK  
    End Dialog wwZ,;\  
    Dim dlg As UserDialog b8UO,fY q  
<%eG:n,#  
    ok = Dialog (dlg) 4+8@`f>s  
1GcE)e!>  
    If ok=0 Then    'cancel button was pressed g!|kp?  
        Print "Execution cancelled." C1)!f j=  
        End ^yp
{32  
    End If 6bC3O4Rw  
SqpaFWr  
    'Assign accommodation and pupil diameter & use defaults if field left empty ZY+qA  
    If dlg.TextBox1 = "" Then v!5 `|\  
        A = 0           'Default accommodation CA~-rv  
    Else lymCH  
        A = CDbl(dlg.TextBox1) CD~.z7,LC  
    End If Svmy(w~m  
99QU3c<.  
    If dlg.TextBox2 = "" Then U
5de@Y  
        pupilDiam = 4   'Default pupil diameter WOap+  
    Else /U9"wvg  
        pupilDiam = CDbl(dlg.TextBox2) f+!(k)GWd  
    End If y<Ot)fa$  
7!E,V:bt'  
    Print " " (!WD1w
 
    Print "Accommodation = " & A & " Diopters" g($2Dk_F2  
    Print "Pupil Diameter = " & pupilDiam & " mm" 8d'0N  
~9@UjQ^)F  
    ' Calculate new parameters with accommodation )SGq[B6@I  
    taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness t{{QE:/  
\4fQMG  
    Rant = 12.0 - 0.4*A                     'Radius of anterior lens 5.GR1kl6  
    CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 3!]rmZ-W  
$!t4r  
    Rpost = -5.224557 + 0.2*A               'Radius of posterior lens G 3ptx! D  
    CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens JWxwJex  
s$j,9uRr  
    tlens = 3.767 + 0.04*A                  'Lens thickness f@!.mDm]  
P&Vv/D  
    nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction d2$IH#~9B  
#H~64/  
    'Adjust parameters to account for accommodation s~X%Y<9l  
cr;da)  
    '************************************************************************* eaU  
    'Aqueous thickness (Position of Lens) R:qW;n%AF  
    '************************************************************************* (E1~H0^  
    eID = FindFullName( "Geometry.Arizona Eye.Lens" ) [nq@mc~<  
    GetCustomElement eID, entity (ToUgVW1N  
JxU5 fe  
    parID = FindFullName( "Geometry.Arizona Eye" ) Q"#J6@  
}Q+|W=2t  
    ' Delete any shift(s) in z @H8EWTZ  
    count = 0 I&5!=kR  
    While GetOperationCount(eID)>count JucY[`|JV  
        GetOperation eID, count, op f|gg  
        If op.Type="ShiftZ" Then 8z\xrY  
            DeleteOperation eID,count E]r?{t`]  
            count=count-1 0"z9Q\{}  
        End If F!K>Kz  
        count=count+1 |_U= z;Y  
    Wend u*9V&>o  
(QB2T2x  
    'Set new shift in f|(M.U-  
    op.Type = "ShiftZ"
Iq.*8Oc  
    op.val1 = taq N'=gep0
V@  
    op.parent = parID \|[;Z"4l  
    AddOperation eID, op #g!.T g'  
    Print "Set aqueous humor thickness = " & taq-0.55 2Tppcj v  
|y!A&d=xYn  
    '************************************************************************* <~=Vg  
    'Radius and conic constant of anterior lens q@2siI~W  
    '************************************************************************* I%Z  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) HxI" 8A  
    GetConic eID, entity, curv, conic TD_Oo-+\  
OZ;*JR:  
    SetConic eID, entity, 1/Rant, CCant cB&:z)i4  
    Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant
PPsE${!  
poFg1  
    '************************************************************************* Ek}A
]zC  
    'Radius and conic constant of posterior lens tq?!-x+>  
    '************************************************************************* FVBYo%Ap  
    eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) NGWxN8P6  
    GetConic eID, entity, curv, conic (7*}-Uy[C  
=g
|FT  
    SetConic eID, entity, 1/Rpost, CCpost i}?>g-(  
    Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost #.[k=dj   

>LuYHr  
    '************************************************************************* Tm?#M&'  
    'Lens thickness (Position of posterior lens surface) TS5Q1+hWHV  
    '************************************************************************* T6k0>[3xf  
?bu>r=oIO]  
    parID = FindFullName( "Geometry.Arizona Eye.Lens" ) [0
e_*  
{l>hMxij  
    ' Delete any z-shift(s) 8~gLqh8^V  
    count = 0 A5w6]:f2  
    While GetOperationCount(eID)>count a.6(K  
        GetOperation eID, count, op v.5+7,4  
        If op.Type="ShiftZ" Then `9.r`&T6K  
            DeleteOperation eID,count PFK  '$  
            count=count-1 T]p-0?=4vv  
        End If ;A!BVq  
        count=count+1 @s^-.z  
    Wend |zE'd!7E  
>&k-'`Nw  
    'Set new z-shift $,'*f?d  
    op.Type = "ShiftZ"
-Y;3I00(  
    op.val1 = tlens */DO ex"y  
    op.parent = parID gPc=2  
    AddOperation eID, op WMg~Y"W  
    Print "Set lens thickness = " & tlens {[>Kob1  
sn>~O4"  
    '************************************************************************* WMP,\=6k0  
    'Lens index of refraction S 6,.FYH  
    '************************************************************************* ]M
'=^32  
    eID = FindMaterial( "Lens" ) M& CqSd  
    GetModelMaterial eID, mat +d-NL?c  
GowH]MO  
    mat.Nd = nlens Dn}Jxu'(  
    SetModelMaterial eID, mat ei5~&  
    Print "Set lens index of refraction = " & nlens D|#E9OQzs  
da~],MN  
    '************************************************************************* C"]^Q)aJN  
    'Pupil diameter *HB-QIl  
    '************************************************************************* gv{ >`AN  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) FU<Jp3<%  
?[>3QE  
    'Adjust pupil diameter (trimming volume inner hole) kz7(Z'pw  
gKCX|cULY  
    SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" G9@0@2aY8  
w)jISu;RG  
    ' Adjust pupil location to just in front of the lens 8sK9G` k  
    parID = FindFullName( "Geometry.Arizona Eye" ) Nl
(Foya%)  
    eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) HLHz2-lI  
    count = 0 #yvGK:F  
    While GetOperationCount(eID)>count y L~W.H  
        GetOperation eID, count, op rk)`\=No  
        If op.Type="ShiftZ" Then ~.lPEA %%  
            DeleteOperation eID,count ;P&OX5~V  
            count=count-1 Y:)e(c"A  
        End If *G9V'9  
        count=count+1 @gXx1hEg  
    Wend BJo*'US-Q  
    op.Type = "ShiftZ" n@[O|?S  
    op.val1 = taq-0.01 ]:/Q]n^  
    op.parent = parID G;XxBA  
    AddOperation eID, op '>C5-R:O  
SOvF[,+  
    Print "Set pupil diameter = " & pupilDiam tIS<U(N;  
Nu~lsWyRI5  
    'Update AZ Eye subassembly Description &UlWCOo8  
    eID = FindFullName( "Geometry.Arizona Eye" ) VTHH&$ZNq  
    GetEntity eID, entity _/<x  
    entity.Description = "Accommodation = " & A & "D" @2v_pJy^  
    SetEntity eID, entity KdbHyg<4  
@49S`  
    Update X+]G-  
    Print "DONE!" QUQ'3  
     %3''}Y5  
End Sub y Fq&8 x<X  
WvZ8/T'x  
如果屈光度是4，光瞳直径是4，则会输出如下数据： {3vNPQJ  
?p8_AL'RS  
Accommodation = 4 Diopters gt w Q-  
Pupil Diameter = 4 mm D*|Bb?  
Set aqueous humor thickness = 2.81 WQO) =n  
Set anterior lens radius = 10.4 and conic constant = -2.375869 K8Y=S12Ti  
Set posterior lens radius = -4.424557 and conic constant = -3.081019 2P{Gxz<#  
Set lens thickness = 3.927 T:W4$P  
Set lens index of refraction = 1.42672 x;<W&s}(  
Set pupil diameter = 4 5bpEYW+  
DONE! >Wg hn:^  
:tv,]05t  
Jo23P.#<  
QQ：2987619807 e6RPIg