Arizona眼睛模型

%Ip*Kq-   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。 );FS7R   L\%orLEmK   模型 *JX;|S   k &/OU:7Y   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。 "%qzj93>   Table 1. AZ眼睛模型的定义 5T@aCC@$h   "4o=,$E=   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. $q$7^r@   JH8}Ru%Z   光源 `=UWqb(K_   GZip\S4Y   多个光源定义来分析该模型的不同特性。图1显示了所以的光源和提示信息告诉您他们可以用来做什么。 _oG&OJ@   FAsFjRS   图1. 光源和提示信息使用 q%Yn;g|_   nKoiG*PI   除了“Letter F”之外的所有光源的光线位置设定在了孔径光阑位置处，并增加了pre-propagation distance= -8。尽管光线在光瞳处创建，规定的传输方向相对于光线位置在pre-propagation distance之后。这意味着光束沿着Z轴在眼睛的前面以平行光入射，而不是在光瞳处入射。 Hc^W%t~   X]%itA   在往下看是内置的脚本用来修改屈光度，使其为4（250mm），光源“Letter F”在视网膜处生成一个字母为F的图像。绿色的光线聚焦的非常好而红色和蓝色光线有一点的模糊。使用Positions Spot Diagram分析工具来观察最为合适。 0@I S   图2. 字母F光源的设定方法光 nUS| sh   zK|i='XSf   图3. 字母F在视网膜上位置点列图 vi.w8>CE   ?W>qUr Z   视网膜的散射 w[tmCn +   M_g?<rK   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 3ZEB   ZJPmR/OV_   图4. 视网膜朗伯散射设定 >-8cU_m7s   aJ Z"D8C   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 V!v:]E   b~=0[Rv   图5. 视网膜重点采样规格设定 /!h;c$   0k)rc$eDF+   脚本 kF(n!2"W   [AMAa]^   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： 'k;rH!R   图6. 用户对话框的创建与编辑 1W7%1FA   图7. 用户对话框编辑器 2c6g>?   `F<jLU^3   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。 g0R~&AN!g   余下的脚本计算与屈光度有关的所有参数。 1 zw*/dp   %\]*OZ7   分析 ~t9tnLc$   J'$>Gk]   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 A,sr[Pa@   图7. 字母F在视网膜上颜色分析 ry9 T U   /xtq_*I1S   脚本代码 .X# `k   hn#1%p6t   Option Explicit     'Remove this to enable non-dimensioned variables to be used. y;_% W   i&{DOI%w   Dim entity As T_ENTITY ,]bB9tid   Dim op As T_OPERATION zR2B- &]H   Dim mat As T_MODELMATERIAL ]a5 f2lE   Dim A As Double T5a*z}L5   Dim pupilDiam As Double 4R18A=X   Dim eID As Long (=7Cs   Dim parID As Long Z#rB}   Dim count As Integer 'yMF~r3J   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double &=VDASEu   Dim tlens As Double, nlens As Double sI{ M   Dim curv As Double, conic As Double nBk)WX&[K   Dim ok As Long (sh)TBb5   0PlO(",a   Sub Main v`M3eh@$A   ZYC<Wb)I       '用户输入对话框 %Dwk       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 IiG6<|d8H           TextBox 220,21,40,21,.TextBox1 'default: 0 +HBd %1           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 =Xo =Qcr           OKButton 40,91,90,21 O)[1x4U           CancelButton 190,91,90,21 z CvKDlL           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 B)0i:"q           TextBox 220,49,40,21,.TextBox2 'default: 4 U&?v:&c#&n       End Dialog D8$G`~hD       Dim dlg As UserDialog V$ ps>   BocSwf;v.       ok = Dialog (dlg) ouuuc9x]   MdvcnaCG       If ok=0 Then    'cancel button was pressed xL\0B,]           Print "Execution cancelled." 2AMo:Jqv           End / pT=0=       End If Ymg|4 %O@   <ZNzVnVA       'Assign accommodation and pupil diameter & use defaults if field left empty 1,% R;7J=g       If dlg.TextBox1 = "" Then Y\No4w ^|d           A = 0           'Default accommodation N<XNTf       Else NxsBX:XDn           A = CDbl(dlg.TextBox1) >U[j]V]       End If NfjE`   d8c=L8~jt       If dlg.TextBox2 = "" Then 5yP\I+Fm           pupilDiam = 4   'Default pupil diameter  |'B7v i)       Else .=s&EEF           pupilDiam = CDbl(dlg.TextBox2) ;IZwTXu!S       End If [D\k^h   AJF#Aw `o       Print " " /w}u3|L$       Print "Accommodation = " & A & " Diopters" e]zBf;9J       Print "Pupil Diameter = " & pupilDiam & " mm" G;l_|8<t#\   ^SF&=NpV       ' Calculate new parameters with accommodation % ~H=sjg       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness H" 3fT0   8ap%?       Rant = 12.0 - 0.4*A                     'Radius of anterior lens |R/%D%_g       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens "i[@P)   VgZsB$Ori       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens Al}B34.uh       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens ^LoUi1j   X:nN0p #       tlens = 3.767 + 0.04*A                  'Lens thickness SC)g^E#   huh6t !       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction n<z[J=I   9 a!$z!.       'Adjust parameters to account for accommodation >JFO@O5   :LW4E9O= H       '************************************************************************* +|n*b       'Aqueous thickness (Position of Lens) ?kbiMs1;u       '************************************************************************* l~w2B>i)       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) f'EuY17w       GetCustomElement eID, entity Lr~=^{   a%/9v"}       parID = FindFullName( "Geometry.Arizona Eye" ) 42$VhdG   K;?m';z0       ' Delete any shift(s) in z  0=2@       count = 0  KY$)#i       While GetOperationCount(eID)>count 3q\,$*D.           GetOperation eID, count, op 5K>3My #           If op.Type="ShiftZ" Then uKUiV%p!               DeleteOperation eID,count "K6&dk jY               count=count-1 4;yKOQD|           End If !Prg_6 `           count=count+1 &8Cu#^3       Wend Q ayPo]O   $P/~rZ@M@       'Set new shift in YNKHN2E8       op.Type = "ShiftZ" !Qu"BF       op.val1 = taq -#u=\ 8       op.parent = parID Z>:NPZODf       AddOperation eID, op e>+i>/Fn{h       Print "Set aqueous humor thickness = " & taq-0.55 f e\$@-   7)`nD<j5       '************************************************************************* Y']\Jq{OS       'Radius and conic constant of anterior lens {Aw#?#GPW       '************************************************************************* v_+{'F       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) }YGV\Nu       GetConic eID, entity, curv, conic ! >(7+B3E*   jnO9j_CY       SetConic eID, entity, 1/Rant, CCant !Xf5e*1IS       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant .sh a&   pjKWtY@=X       '************************************************************************* *2pt%eav       'Radius and conic constant of posterior lens =_JjmTy;a       '************************************************************************* ?+@n3]`0       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) B+P(M!m3       GetConic eID, entity, curv, conic } gyj0   <wN}X#M       SetConic eID, entity, 1/Rpost, CCpost /M1ob:m       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost %9KldcQ}~   c}lb%^;)E       '************************************************************************* q9KHmhUD       'Lens thickness (Position of posterior lens surface) X5zDpi|Dq       '************************************************************************* BKCA<   LiN$ pwm       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) lA| 5E?   V,lOt4b       ' Delete any z-shift(s) ~7*.6YnI       count = 0 q/4J.jL       While GetOperationCount(eID)>count \ub7`01           GetOperation eID, count, op BTqS'NuT           If op.Type="ShiftZ" Then ZCMw3]*               DeleteOperation eID,count $v4.sl:x               count=count-1 T"{>t           End If Qp)v?k ]           count=count+1 vOn`/5-       Wend M8kPj8}{   UdT*E: 6       'Set new z-shift g0xuxK;9c       op.Type = "ShiftZ" ~ (|5/ p7t       op.val1 = tlens >c1qpk/       op.parent = parID GFj{K       AddOperation eID, op |7'df&CA       Print "Set lens thickness = " & tlens n,vct<&z@   mitHT :%r2       '************************************************************************* T,,WoPU8t       'Lens index of refraction ^cOUQ33       '************************************************************************* 1-8mFIK       eID = FindMaterial( "Lens" ) y`Wty@       GetModelMaterial eID, mat  ~^NtO   =Gpylj7?~       mat.Nd = nlens jD$,.AVvz       SetModelMaterial eID, mat RuLi,'u       Print "Set lens index of refraction = " & nlens R/~p>apg8   e>} s;H,       '************************************************************************* faEt6       'Pupil diameter l5S aT,%       '************************************************************************* Q- cFtu-w       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) .?8;qA   Z^bQ^zk-       'Adjust pupil diameter (trimming volume inner hole) *RI]?j%B   u 1>2 v       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" 8zZvht*   ~Otq %MQ       ' Adjust pupil location to just in front of the lens FvaUsOy "       parID = FindFullName( "Geometry.Arizona Eye" ) lp.ldajN       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) k0OYJ/       count = 0 <wk!hTmW       While GetOperationCount(eID)>count hi_NOx           GetOperation eID, count, op EuZ<quwWg           If op.Type="ShiftZ" Then :i0uPh\0               DeleteOperation eID,count kjTduZ/3"               count=count-1 Yxr>"KH6a           End If Tm~" IB*           count=count+1 T;Lka xsn       Wend 0!4Ts3qn1       op.Type = "ShiftZ" ;"a=gr       op.val1 = taq-0.01 I,E?h?6Y       op.parent = parID *z5.vtfu!       AddOperation eID, op U\g/2dM   "IZa!eUW       Print "Set pupil diameter = " & pupilDiam xs{3pkTYD   !S$:*5=&       'Update AZ Eye subassembly Description NxkGOAOE       eID = FindFullName( "Geometry.Arizona Eye" ) bg!/%[ {M       GetEntity eID, entity ahJ`T*) HY       entity.Description = "Accommodation = " & A & "D" u}#(.)a:       SetEntity eID, entity R|6Cv3:   K?6jXJseb       Update 1auIR/=-       Print "DONE!" W\>fh&!)        Lm iOhx   End Sub 35h8 O,Y   [8Y:65   如果屈光度是4，光瞳直径是4，则会输出如下数据： :N:yLd} &    `xKp%9   Accommodation = 4 Diopters BOX{]EOj   Pupil Diameter = 4 mm 'f#{{KA   Set aqueous humor thickness = 2.81 R"-mKT}   Set anterior lens radius = 10.4 and conic constant = -2.375869 d?y4GkK   Set posterior lens radius = -4.424557 and conic constant = -3.081019 ?k+xSV   Set lens thickness = 3.927 +cJL7=V&   Set lens index of refraction = 1.42672 Jz\%%C   Set pupil diameter = 4 qSM|hHDo)   DONE!

zN[hkmh

MR;1 2*p