Arizona眼睛模型

>7%Gd-;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。 dqwCyYC    d(PS   模型 nXHU|5.I   H9'Y` -r   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。 _  dFZR   Table 1. AZ眼睛模型的定义 M$&aNt;   rP aUDR4U   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. U~!yGjF   >C,=elM   光源 "fWAp*nI3t   !GJnYDN   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。 i,HafY   [@ExR*   图1. 光源和提示信息使用 1=LI))nV   ul0]\(sS:   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。 OO)m{5r,{   ,_HSvs7-   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。 Glz)-hjJ:n   图2. 字母F光源的设定方法光 3Z?"M   Y1e>P   图3. 字母F在视网膜上位置点列图 .iK{=L/(y   s$g"6;_\   视网膜的散射 ?^TjG)e7   E]G#"EV!Y   在散射文件中，有一个名为“Retina surface”的72%的反射型朗伯散射，它为视网膜的散射提供了一个粗略的近似。为了模拟来自视网膜的散射，改变自定义元件“Eye ball” 下的视网膜的表面从“halt all” 到”Allow All”。并使几何中“plane”可追迹。 .&Uu w   nXjf,J-T   图4. 视网膜朗伯散射设定 5Ym/'eT   MUo}Qi0K   注意在视网膜的表面有散射重点采样规格定义，在“Scatter”标签的底部可获取该信息。“toward pupil”指定散射光朝向光瞳，半角度10度。 ;dXQB>Za   tI651Wm9   图5. 视网膜重点采样规格设定 l2>ka~   }e}J6[wP   脚本 AvW2)+6G   CV/ei,=9   内置脚本使用对话框显示屈光度和光瞳直径的数值设置。使用FRED Basic脚本创建和使用对话框非常容易。图6显示了如何获取用户自定义对话框，如下图所示： 0Q@ &z   图6. 用户对话框的创建与编辑 5DgfrX   图7. 用户对话框编辑器 2-G he3   3GEI)!   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 3+6s}u)   余下的脚本计算与屈光度有关的所有参数。 d* 7nz=0&$   ;;z4EGr   分析 5<o8prtB   W,</   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 F,2)Udim   图7. 字母F在视网膜上颜色分析 :1Jg;G   F+.:Ry FS   脚本代码 21 Z}Zj   ka_]s:>+   Option Explicit     'Remove this to enable non-dimensioned variables to be used. S1 22. I   A%H"a+   Dim entity As T_ENTITY YGy.39@31   Dim op As T_OPERATION )4oTA@wR   Dim mat As T_MODELMATERIAL wLeP;u1   Dim A As Double %E q}H   Dim pupilDiam As Double mjdZ^   Dim eID As Long (rfU=E   Dim parID As Long |2mm@):   Dim count As Integer ><odBM-   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double UEeD Nl$^u   Dim tlens As Double, nlens As Double YXCfP ~i   Dim curv As Double, conic As Double %{$iN|%J%$   Dim ok As Long Wi3:;`>G<p   mSSDV0Pfn   Sub Main Ps3wg=ni[   w4YuijhW       '用户输入对话框 wfH#E2+pk       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 w i,}sEoM           TextBox 220,21,40,21,.TextBox1 'default: 0 3DH} YAUU           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 >3R)&N           OKButton 40,91,90,21 }?zy*yL           CancelButton 190,91,90,21 E"p;           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 feOX ]g#           TextBox 220,49,40,21,.TextBox2 'default: 4 }E626d}uA       End Dialog =b{wzx}e       Dim dlg As UserDialog "F nH>g-   };5d>#NK,Y       ok = Dialog (dlg) Gh3b*O_,   |E/r64T       If ok=0 Then    'cancel button was pressed %3B0s?,I           Print "Execution cancelled." y7ng/vqM7           End .W[ 9G\       End If }GV5':W@WG   (~6oA f       'Assign accommodation and pupil diameter & use defaults if field left empty V/C":!;       If dlg.TextBox1 = "" Then QMUmPx&           A = 0           'Default accommodation Z_iVOctP       Else }=. :bwX5           A = CDbl(dlg.TextBox1) zo!e<>o       End If g\;&Z   s,&tD WU       If dlg.TextBox2 = "" Then 1ztL._Td           pupilDiam = 4   'Default pupil diameter ''Lf6S`4X~       Else 2$G,pT1J           pupilDiam = CDbl(dlg.TextBox2) b#XY.+ *0       End If vU tA@   qX,TX 3       Print " " H B+{vuN*L       Print "Accommodation = " & A & " Diopters" 2`2S94'       Print "Pupil Diameter = " & pupilDiam & " mm" ,OGXH2!h   /XfE6SBz       ' Calculate new parameters with accommodation /*v}.fH%       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness VZ69s{/.B   zh{:zT)(1       Rant = 12.0 - 0.4*A                     'Radius of anterior lens X:3W9`s)*       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens H_ecb;|mP   6 07"Z \       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens m]XG7:}V0       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens Dht,!LVb;   *Fb|iR       tlens = 3.767 + 0.04*A                  'Lens thickness Y/|wOm;|   g#??Mz       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction ONc-jU^   SuorCp ]       'Adjust parameters to account for accommodation i'6>_,\(   A9:dHOmT^U       '************************************************************************* &_1Ivaen6       'Aqueous thickness (Position of Lens) xzI?'?duC       '************************************************************************* L("zS%qr       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) b~5Q|3P9       GetCustomElement eID, entity cq?&edjP   O|ODJOQNol       parID = FindFullName( "Geometry.Arizona Eye" ) R=/^5DZ}    Vm_<eyI2       ' Delete any shift(s) in z *{#l0My       count = 0 8D)I~0\       While GetOperationCount(eID)>count <aScA`\B#           GetOperation eID, count, op S*0P[R           If op.Type="ShiftZ" Then BZdryk:S               DeleteOperation eID,count  z]\CI:               count=count-1 Q,AM<\S           End If M~o\K'           count=count+1 7y/Pch       Wend -nsI 5\]   m0$ 4       'Set new shift in 5VLJ:I?0O       op.Type = "ShiftZ" r6x "D3       op.val1 = taq '9w.~@7       op.parent = parID .3Ag6YI0N       AddOperation eID, op 3P&K<M#\       Print "Set aqueous humor thickness = " & taq-0.55 4/Wqeq,E8   (:TZ~"VY       '************************************************************************* Fh3>y2`/       'Radius and conic constant of anterior lens |Nfi y       '************************************************************************* xGU~FU       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) .dr-I7&!       GetConic eID, entity, curv, conic r\x"nS   K9@F1 ccQ/       SetConic eID, entity, 1/Rant, CCant AlH\IP       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant AfV a[{E   [!Jd.zm       '************************************************************************* cc %m0p       'Radius and conic constant of posterior lens \A ?B{*       '************************************************************************* =;!$Qw4       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) }qk8^W{       GetConic eID, entity, curv, conic Q^_*&},V   W-ctx"9DS       SetConic eID, entity, 1/Rpost, CCpost 8=!BtMd"       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost #K[UqJ+x   Fhr5)Z       '************************************************************************* L+rMBa       'Lens thickness (Position of posterior lens surface) l^ Q-KUI       '************************************************************************* GIyb0XjTw   Z%t"~r0PS       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) qVpV ZH!   d8o<Q 9       ' Delete any z-shift(s) 7v8V0Gp       count = 0 ]3%( '8/       While GetOperationCount(eID)>count 5R?[My           GetOperation eID, count, op 5,;>b^gXY`           If op.Type="ShiftZ" Then 04u^Q               DeleteOperation eID,count Vo@gxC,               count=count-1 i 1{Lx)           End If LMF@-j%           count=count+1 oXQzCjX_       Wend L93PDp4v   )Td;2       'Set new z-shift sX :)g>b        op.Type = "ShiftZ" Xqz\%&G       op.val1 = tlens 9;L5#/E       op.parent = parID nNN~Z'bG       AddOperation eID, op 19r4J(pV       Print "Set lens thickness = " & tlens HVq02 Z   !P_8D* ^9       '************************************************************************* IO*}N"       'Lens index of refraction wOlnDQs       '************************************************************************* \$iU#Z       eID = FindMaterial( "Lens" ) +J`HI1       GetModelMaterial eID, mat d"P\ =`+   f4h|Nn%;       mat.Nd = nlens Xq"_^       SetModelMaterial eID, mat |\ZsoA       Print "Set lens index of refraction = " & nlens !bPsJbIo>   5Dhpcgq<<       '************************************************************************* JFJ_ PphvD       'Pupil diameter Gl4(-e'b       '************************************************************************* 5q.d$K |       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) 5)T=^"IHXi   z)Yk&;XC       'Adjust pupil diameter (trimming volume inner hole) BotGPk><c   (Ov{gj^       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" :3uCW1   yX {CV7%O       ' Adjust pupil location to just in front of the lens e]1&f.K       parID = FindFullName( "Geometry.Arizona Eye" )  l[MP|m#       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) -=tf)       count = 0 D.Q9fa&P       While GetOperationCount(eID)>count xD:t$~           GetOperation eID, count, op <~%e{F:[#           If op.Type="ShiftZ" Then AM[#AZv               DeleteOperation eID,count k^JV37;bl               count=count-1 \z~wm&           End If MHuQGc"e+4           count=count+1 d(=*@epjR       Wend Wk0"U V       op.Type = "ShiftZ" ja<!_^h=At       op.val1 = taq-0.01 ![>j`i       op.parent = parID v$P<:M M       AddOperation eID, op H}nPaw]G   pX\Y:hCug       Print "Set pupil diameter = " & pupilDiam xT]|78h$    DCv=*=6w       'Update AZ Eye subassembly Description c,v?2*<       eID = FindFullName( "Geometry.Arizona Eye" ) r Ljb'\<*       GetEntity eID, entity rryC^Vma       entity.Description = "Accommodation = " & A & "D" 3eg)O34       SetEntity eID, entity Oi?+Z:lak   wWaJ%z>3y       Update |5;:3K+       Print "DONE!" GY%2 EM(        &ody[k?'   End Sub ~"Q24I   h&k*i   如果屈光度是4，光瞳直径是4，则会输出如下数据： Wv4x^nJ   kT=KxS{   Accommodation = 4 Diopters g5\EVcHkz   Pupil Diameter = 4 mm =!~6RwwwY   Set aqueous humor thickness = 2.81 5C G ,l   Set anterior lens radius = 10.4 and conic constant = -2.375869 U#X6KRZ~g   Set posterior lens radius = -4.424557 and conic constant = -3.081019 *!wBn   Set lens thickness = 3.927 >$g+Gx\v4   Set lens index of refraction = 1.42672 }(yX$ 3?`   Set pupil diameter = 4 Q!T+Jc9N   DONE!

0wA?.~ L

KiaQ^[/q