Arizona眼睛模型

"rJJ~[Y   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。 |Vj@;+/j   u ;/5@ADW   模型 p "Cxe   S5(VdMd"^   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。 ^K]`ZQjKC   Table 1. AZ眼睛模型的定义 =mQdM]A)2   k7cM.<s!   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. \}p!S$`   O`rKxP   光源 t)__J\xF   7J6D wh{   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。 oz[ Mt i*   }Tz<fd/   图1. 光源和提示信息使用 &&s3>D^Ta   9Z VzIv(   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。 L8WYxJ k   :g~X"C1s   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。 6VQe ?oh   图2. 字母F光源的设定方法光 9[@K4&   5%#V>|@e#   图3. 字母F在视网膜上位置点列图 KM:k<pvi   N7l`-y   视网膜的散射 3X>x`    RO!em~{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。 ~^<1k-   ; VH:dg   图4. 视网膜朗伯散射设定 0tS< /G8   Pz77\DpFi   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。 l RM7s(^l   bSv r8FY3d   图5. 视网膜重点采样规格设定 D~T;z pS   q?0&&"T}   脚本 uozK'L   ?? 2x*l1   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： $9@jV<Q1   图6. 用户对话框的创建与编辑 ?igA+(.   图7. 用户对话框编辑器 Ucqn3&   *I<L1g%9d   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。 WXmR{za    余下的脚本计算与屈光度有关的所有参数。 9h/JW_   /73ANQ"   分析 7 /7,55   7)zF8 V   屈光度为4，光瞳直径为4mm，字母F点在视网膜上所成的像。 ~zO>Q4-k   图7. 字母F在视网膜上颜色分析 b sM]5^   *u ^mf~   脚本代码 O =gv2e   MY w3+B+Jj   Option Explicit     'Remove this to enable non-dimensioned variables to be used. D3(rD]c0{   DOB#PI[/   Dim entity As T_ENTITY s%/x3anz=   Dim op As T_OPERATION ,~nrNkhp   Dim mat As T_MODELMATERIAL 6+LBs .vl}   Dim A As Double 8:gUo8   Dim pupilDiam As Double {7Qj+e^   Dim eID As Long lK"m|Z   Dim parID As Long m4_ZGjmJM   Dim count As Integer Hpj7EaMZ_   Dim taq As Double, Rant As Double, CCant As Double, Rpost As Double, CCpost As Double |6o!]~&e$1   Dim tlens As Double, nlens As Double q445$ndCT   Dim curv As Double, conic As Double bB+ 4   Dim ok As Long ^hRx{A   FnWN]9   Sub Main >`=9So_J   khQ@DwO*\=       '用户输入对话框 59#o+qo4       Begin Dialog UserDialog 320,126,"Input parameters" ' %GRID:10,7,1,1 >XJUj4B|X           TextBox 220,21,40,21,.TextBox1 'default: 0 ,JqCxb9           Text 20,21,190,21,"Accommodation (in Diopters):",.Text1,1 1%$Z%?           OKButton 40,91,90,21 IcJQC           CancelButton 190,91,90,21 ]S+KH \2           Text 20,49,190,14,"Pupil diameter (4 mm default):",.Text2,1 r0/aw           TextBox 220,49,40,21,.TextBox2 'default: 4 wB+X@AA       End Dialog 60 --6n       Dim dlg As UserDialog .X\9vVJ   ^Rh`XE       ok = Dialog (dlg) vX}#wDN P   36MNaQt'e       If ok=0 Then    'cancel button was pressed ,!vI@>nhG           Print "Execution cancelled." +[2ep"5H           End K};~A?ET,h       End If r) g:-[Ox9   oxNQNJ!X       'Assign accommodation and pupil diameter & use defaults if field left empty GQ\;f       If dlg.TextBox1 = "" Then `Rx\wfr}           A = 0           'Default accommodation !6FO[^h||H       Else [=]LR9c4           A = CDbl(dlg.TextBox1) &a!MT^anA~       End If uJSzz:\   zGtv(gwk       If dlg.TextBox2 = "" Then i9eE/ .           pupilDiam = 4   'Default pupil diameter >Vph_98|       Else XsGc!o           pupilDiam = CDbl(dlg.TextBox2) fk2p}       End If j@.^3:   8}K4M(       Print " " .~,=?aq^       Print "Accommodation = " & A & " Diopters" #CRd@k?       Print "Pupil Diameter = " & pupilDiam & " mm" ^4Tf6Fw#   F% z$^ m-       ' Calculate new parameters with accommodation _sK{qQxvM=       taq = 0.55 + 2.97 - 0.04*A              'Aqueous thickness |_mN:(3   }v6@yU       Rant = 12.0 - 0.4*A                     'Radius of anterior lens uc Ph*M       CCant = -7.518749 + 1.285720*A          'Conic constant of anterior lens & ^;3S*p   W!V-m       Rpost = -5.224557 + 0.2*A               'Radius of posterior lens O,Ej m<nt       CCpost = -1.353971 - 0.431762*A         'Conic constant of posterior lens y' RQ_Gi   u;9a/RI       tlens = 3.767 + 0.04*A                  'Lens thickness rGlnu.mK^   'x<o{Hi"\B       nlens = 1.42 + 0.00256*A - 0.00022*A^2  'Lens index of refraction [LM9^*sG2V   PZihC       'Adjust parameters to account for accommodation zs.@=Z"   ;: 0<(!^*       '************************************************************************* r"!xI       'Aqueous thickness (Position of Lens) CU@}{}Yl       '************************************************************************* Ch_eK^ g1       eID = FindFullName( "Geometry.Arizona Eye.Lens" ) M{g. x4M@W       GetCustomElement eID, entity 20/P:;   ej,R:}C%`       parID = FindFullName( "Geometry.Arizona Eye" ) O=}d:yZb!   [ d`m)MW-       ' Delete any shift(s) in z 2  Z yO       count = 0 z) x.6       While GetOperationCount(eID)>count :!wl/X ~           GetOperation eID, count, op D2I|Z           If op.Type="ShiftZ" Then Y|S>{$W               DeleteOperation eID,count Nx"|10gC               count=count-1 EMzJyGt7           End If nP_)PDTFp           count=count+1 [1e]_9)p       Wend C!U$<_I\2   =w/AJ%6       'Set new shift in B+z>$6       op.Type = "ShiftZ" }/QtIY#I       op.val1 = taq W3jwc{lj       op.parent = parID VniU:A       AddOperation eID, op \027>~u {       Print "Set aqueous humor thickness = " & taq-0.55 i,wZNX   5?m4B:W       '************************************************************************* M(vX.kF       'Radius and conic constant of anterior lens gYBMi)`RT       '************************************************************************* P!I Lji!       eID = FindFullName( "Geometry.Arizona Eye.Lens.Anterior" ) $b)t`r+       GetConic eID, entity, curv, conic T+oOlug   6!SW]#sD       SetConic eID, entity, 1/Rant, CCant 4v`G/w       Print "Set anterior lens radius = " & Rant & " and conic constant = " & CCant _*Ej3=u   $Z3{D:-)       '************************************************************************* W#2} EX       'Radius and conic constant of posterior lens 10xza=a       '************************************************************************* u4$R ZTC       eID = FindFullName( "Geometry.Arizona Eye.Lens.Posterior" ) b!r%4Ah       GetConic eID, entity, curv, conic q:=jv6T#   B$qTH5)W       SetConic eID, entity, 1/Rpost, CCpost w c       Print "Set posterior lens radius = " & Rpost & " and conic constant = " & CCpost z[@i=avPG   @^/aS;B$>       '************************************************************************* xQl}~G]!       'Lens thickness (Position of posterior lens surface) Z5 7.+z<       '************************************************************************* +X`&VO6~   %cBOi_}}~       parID = FindFullName( "Geometry.Arizona Eye.Lens" ) Yr>0Qg],   2A:&Cqo       ' Delete any z-shift(s) _l+C0lQ l=       count = 0 = 5[%%Lf       While GetOperationCount(eID)>count 'Va<GHr>+           GetOperation eID, count, op 5~ZzQG           If op.Type="ShiftZ" Then _%Yi^^               DeleteOperation eID,count C_JO:$\rE               count=count-1 R x( yn           End If !a25 cm5ys           count=count+1 {rK]Q! yj       Wend OZC yg/K   I0qJr2[X~       'Set new z-shift ||ugb6q[6B       op.Type = "ShiftZ" d]:G#<.       op.val1 = tlens ,Xr`tQ<@       op.parent = parID 9dm<(I}       AddOperation eID, op H_Xk;fM       Print "Set lens thickness = " & tlens 78r0K 5=   __zHe-.m       '************************************************************************* 9Ofls9]U       'Lens index of refraction b- bvkPN       '************************************************************************* 8_o~0lb       eID = FindMaterial( "Lens" ) "Q:h[) a       GetModelMaterial eID, mat .Z#/%y3S   zR<fz       mat.Nd = nlens *_7/'0E(3       SetModelMaterial eID, mat TD%L`Gk       Print "Set lens index of refraction = " & nlens @WJ\W`P   ALcPbr       '************************************************************************* 42p1P6d       'Pupil diameter BoST?"&}'       '************************************************************************* \q3ui}-9       eID = FindFullName( "Geometry.Arizona Eye.Pupil.Iris" ) Dv L8}dz   ?>iU z.];t       'Adjust pupil diameter (trimming volume inner hole)  UO#`Ak   yimK"4!j5A       SetTrimVolHole eID, pupilDiam/2, pupilDiam/2, 0, 0, "Cylinder" z+{+Q9j   u~2]$ /U       ' Adjust pupil location to just in front of the lens :YOo"3.]       parID = FindFullName( "Geometry.Arizona Eye" ) 4=EA3`l       eID = FindFullName( "Geometry.Arizona Eye.Pupil" ) bo(w$& VW       count = 0 TIt\       While GetOperationCount(eID)>count M] +.xo+A           GetOperation eID, count, op Ok|Dh;1_           If op.Type="ShiftZ" Then L &hw-.Q               DeleteOperation eID,count 17,mqXX>               count=count-1 A_WaRYG           End If 3"< 0_3?W           count=count+1 + d 3       Wend &:IcwD&       op.Type = "ShiftZ" g ujP{Z       op.val1 = taq-0.01 (>f`>6 V       op.parent = parID z6rT<~xZtu       AddOperation eID, op iRlpNsN   Ir5|H|b<       Print "Set pupil diameter = " & pupilDiam 2    %?aq1 =B       'Update AZ Eye subassembly Description 8D,*_p       eID = FindFullName( "Geometry.Arizona Eye" ) &"I csxG       GetEntity eID, entity ?FjnG_Uz`D       entity.Description = "Accommodation = " & A & "D" Q;!r N)       SetEntity eID, entity iU37LODa2T   XPD1HN!,LT       Update EApbaS}Up       Print "DONE!" @SpP"/)JY        ; :q   End Sub '21gUYm   S4[#[w`=   如果屈光度是4，光瞳直径是4，则会输出如下数据： hjM?D`5x   &e;Qabwxva   Accommodation = 4 Diopters 3+s$K(%I   Pupil Diameter = 4 mm V$w lOMp   Set aqueous humor thickness = 2.81 noL9@It0   Set anterior lens radius = 10.4 and conic constant = -2.375869 {jmy:e2   Set posterior lens radius = -4.424557 and conic constant = -3.081019 *B}O   Set lens thickness = 3.927 .RJMtmp   Set lens index of refraction = 1.42672 %lWOW2~R   Set pupil diameter = 4 *o4a<.hd2   DONE!

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