Arizona眼睛模型

:9(3h"   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`l{   q_-ma_F#s   模型 f_oq1W)9   S  <2}8D   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。 %_>Tcm=   Table 1. AZ眼睛模型的定义 xC<R:"Mn   x cHen/4X   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. ,Qat    ~q*i;*   光源 64?Pfir6   VK9Q?nu   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。 q5%2WM]6   IDj_l+?c   图1. 光源和提示信息使用 xM% pvx.'L   PXa5g5!   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。 +-U@0&Y3M   w-r_H!-   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。 =D{B}=D\IM   图2. 字母F光源的设定方法光 l(gJLjTH%   -<xyC8$^$   图3. 字母F在视网膜上位置点列图 w %;hl#s   g`kY]lu   视网膜的散射 b9`iZ   vu XS/ d   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。 Gv;;! sZ   =PV/`I_h   图4. 视网膜朗伯散射设定 )Ea8{m!   `ovgWv   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。 yE}BfU {.   I|Z/`9T   图5. 视网膜重点采样规格设定 %Mh Q   U{"f.Z:Ydo   脚本 ?<! nm&~   "@4ghot t   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： u %'y_C3   图6. 用户对话框的创建与编辑 Z{} n8b*   图7. 用户对话框编辑器 r?\|f:M3   $Y6 3!*   如果“OK”按钮按下，将会核对对话框下面的代码行，如果点击取消则脚本终止。然后输入的参数赋予变量，如果此处是保留为空白，则使用默认值。因此，如果没有值输入并点击“OK”按钮，则脚本是以屈光度为0，光瞳直径为4mm来运行的。 !5&%\NSv   余下的脚本计算与屈光度有关的所有参数。 EA6t36|TX   <>]1Y$^Y   分析 _AprkI_   jM]d'E?ZLA   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 RE 9nU%!   图7. 字母F在视网膜上颜色分析 #\LZ;&T'N   t}VwVf<K   脚本代码 Qo.Uqz.C   yQ'eu;+]   Option Explicit     'Remove this to enable non-dimensioned variables to be used. Lbsr_*4t   U_l7CCK +   Dim entity As T_ENTITY BMpF02Y|4   Dim op As T_OPERATION )%qtE34`   Dim mat As T_MODELMATERIAL U-eI\Lu   Dim A As Double 9s(i`RTM   Dim pupilDiam As Double .1LPlZ   Dim eID As Long Y87XLvig}   Dim parID As Long 0vn[a,W<A   Dim count As Integer MQJ%He"   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double >ukQ, CE~   Dim tlens As Double, nlens As Double e=7W7^"_   Dim curv As Double, conic As Double 'l|R5    Dim ok As Long =-Nsc1&   %l]Rh/VPn?   Sub Main lufe ieW   1q]&7R       '用户输入对话框 1A^1@^{m'       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 c" +zgP           TextBox 220,21,40,21,.TextBox1 'default: 0 E MQ4yK           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 {]`p&@           OKButton 40,91,90,21 m6i%DE           CancelButton 190,91,90,21 R*bmu           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 H2U:@.o2&           TextBox 220,49,40,21,.TextBox2 'default: 4 %'0&ElQ       End Dialog qp&4 1       Dim dlg As UserDialog P6YQK+   (sCAR=5v\       ok = Dialog (dlg) k;Hnu   Xpl?g=B&u       If ok=0 Then    'cancel button was pressed ,Kw5Ro`I:           Print "Execution cancelled." .,M;hu Rg           End Y@%`ZPJ       End If K&dT(U   NAJVr}4f       'Assign accommodation and pupil diameter & use defaults if field left empty *ik/p       If dlg.TextBox1 = "" Then ,{8v4b-           A = 0           'Default accommodation 5un^yRMB-       Else c`jDW S           A = CDbl(dlg.TextBox1) :u/mTZDi       End If b#a@rh   J633uH}}       If dlg.TextBox2 = "" Then `WnQ           pupilDiam = 4   'Default pupil diameter .6m_>Y6       Else oHX$k{6           pupilDiam = CDbl(dlg.TextBox2) ,E}$[mHyjz       End If J +q|$K6   X#ZgS!Mn       Print " " R ]P;sk5       Print "Accommodation = " & A & " Diopters" ]?&FOzN5$P       Print "Pupil Diameter = " & pupilDiam & " mm" 6Dst;:   8r^ ~0nm       ' Calculate new parameters with accommodation %K1")s       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness !` 2 6\@1   m|F:b}0Hb       Rant = 12.0 - 0.4*A                     'Radius of anterior lens ,2,5Odrz       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens 9/kXc4   VLdB_r3lQ       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens 1'O0`Me>#       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens g_q<ze   E\$C/}T       tlens = 3.767 + 0.04*A                  'Lens thickness $Q/Ya@o   0+`Pg       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction h}&b+1{X   X+l'bp]Ry       'Adjust parameters to account for accommodation t&}6;z 3   Yb:pAzw6       '************************************************************************* XYfv(y       'Aqueous thickness (Position of Lens) 61@EDIYPc       '************************************************************************* +S9PML){h       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) &&7r+.Y       GetCustomElement eID, entity FS@A8Bb   Nfn(Xn*J-       parID = FindFullName( "Geometry.Arizona Eye" ) [BDGR B7d"   "HlgRp]u       ' Delete any shift(s) in z &leK}je [       count = 0 Yc;ec9~       While GetOperationCount(eID)>count NXU`wnVJ           GetOperation eID, count, op d,9`<1{9           If op.Type="ShiftZ" Then >EP(~G3u               DeleteOperation eID,count |B^G:7c               count=count-1 &`Ck           End If HOZRYIQB           count=count+1 6rX_-Mm6w       Wend Jpj!rXTX*   qp~gP       'Set new shift in n]N96oD       op.Type = "ShiftZ" 0LL c 1t>}       op.val1 = taq YZE.@Rz       op.parent = parID H{(]9{       AddOperation eID, op nE|@IGH       Print "Set aqueous humor thickness = " & taq-0.55 ^gYD*K!*   Cifd21v4       '************************************************************************* ?c#$dc"       'Radius and conic constant of anterior lens z`U Ukl}T       '************************************************************************* Qe$k3!       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) Q@QFV~       GetConic eID, entity, curv, conic A3{0q>CC   m*e YC       SetConic eID, entity, 1/Rant, CCant Q+$Tt7/       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant Y (6S p'0   ]%dnKP~       '************************************************************************* 23ze/;6%A       'Radius and conic constant of posterior lens H0*,8i5I       '************************************************************************* ,k0r       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) kB P*K       GetConic eID, entity, curv, conic )qU7`0'8   MI#mAg<       SetConic eID, entity, 1/Rpost, CCpost vqNsZ 8|`       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost Y+-xvx :   - u3e5gW       '************************************************************************* csQfic       'Lens thickness (Position of posterior lens surface) LE=k       '************************************************************************* %[QV,fD'E   S h4wqf       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) XbXA+ey6   lU2c_4       ' Delete any z-shift(s) d- E4~)Qy       count = 0 L;6. r3bL       While GetOperationCount(eID)>count 2eP;[o           GetOperation eID, count, op }5 9U}@xC           If op.Type="ShiftZ" Then -yx/7B5@               DeleteOperation eID,count \nvAa_,               count=count-1 =zg:aTMti           End If E~hzh /,34           count=count+1 53OJ-m%a       Wend }_OM$nzj   #-#NqX:       'Set new z-shift H-5<S@8       op.Type = "ShiftZ" oFC)       op.val1 = tlens USPTpjt8R       op.parent = parID >cR)?P/o       AddOperation eID, op ,?-\ x6       Print "Set lens thickness = " & tlens k9si|'   O&Z'r       '************************************************************************* tj1JB%       'Lens index of refraction Q(@IK&v       '************************************************************************* 9w4sSj`       eID = FindMaterial( "Lens" ) -_^c6!i       GetModelMaterial eID, mat ;</Lf=+Vm   0@=MOGQb       mat.Nd = nlens u<tk G B       SetModelMaterial eID, mat `NNf&y)y       Print "Set lens index of refraction = " & nlens s d 0r'jb   {rH9grb       '************************************************************************* EeQ5vqU       'Pupil diameter Rm>^tu -       '************************************************************************* +8P,s[0<R_       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) WE!vSZ3R   Tupi q       'Adjust pupil diameter (trimming volume inner hole) &xSa7FY   0tz:Wd*<       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" =tdSq"jh   i%{X9!*%TX       ' Adjust pupil location to just in front of the lens zY9H%       parID = FindFullName( "Geometry.Arizona Eye" ) 15H6:_+=0       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) L2z2}U=<       count = 0 t}p@:'       While GetOperationCount(eID)>count +C{p%`<           GetOperation eID, count, op 6LUC!Sh           If op.Type="ShiftZ" Then `sHuM*               DeleteOperation eID,count r0dDHj~F               count=count-1 ^HA %q8| n           End If ?pGkk=,KB           count=count+1 \F6LZZ2Lv       Wend '\DSTr:N       op.Type = "ShiftZ" H#d:kilNy       op.val1 = taq-0.01 d5j_6X       op.parent = parID O}ejWP8>       AddOperation eID, op Jobiq]|>   x8#ODuH       Print "Set pupil diameter = " & pupilDiam X a9TS"   $0Yh!L?\       'Update AZ Eye subassembly Description Es5p}uh.[Y       eID = FindFullName( "Geometry.Arizona Eye" ) ]`=X'fED       GetEntity eID, entity j) vlM+       entity.Description = "Accommodation = " & A & "D" ZU&"73        SetEntity eID, entity tykB.2f   ZU2laqa_       Update E@)\Lc~       Print "DONE!" 3K0tC=        GUB`|is^   End Sub IO$z%r7   U yqXMbw@   如果屈光度是4，光瞳直径是4，则会输出如下数据： hsLzj\)6   8cg`7(a   Accommodation = 4 Diopters #VbVsl   Pupil Diameter = 4 mm 2ef;NC.&n   Set aqueous humor thickness = 2.81 ,d,\-x-+/   Set anterior lens radius = 10.4 and conic constant = -2.375869 Y}R}-+bD/   Set posterior lens radius = -4.424557 and conic constant = -3.081019 LJzH"K[Gg6   Set lens thickness = 3.927 gQWd&)'muf   Set lens index of refraction = 1.42672 2(YPz|~W   Set pupil diameter = 4 vR7HF*8   DONE!

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