[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： B}8xA}<  
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RPC Photonics公司有高品质的的工程漫射体BSDF测试数据，但它对于FRED帮助甚少，下面这个步骤描述了如何利用FRED脚本转换RPC Photonics提供的TXT文件，并将数据直接应用到FRED的Tabulated scatter 散射模型。 VVO C-:  
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背景： C-lv=FJEk/  
Thorlabs和RPC Photonics联手共同推出的新型漫射体及光束整形技术，可以解决其他技术的不足，大大改善了诸如光刻系统、有效固态照明，显示，背光，显示亮度增强和投影屏等大多数应用的性能。这项我们称之为工程漫射体（Engineered DiffusersTM）的新概念，与其他技术有许多不同。与诸如磨砂玻璃、乳色玻璃和全息元件等随机漫射体截然不同，工程漫射体要求对于每个散射中心，通常为微透镜单元，都进行控制。例如全息漫射体可以视为一组随机排列的透镜，但是通过全息曝光形成的类透镜效果只能通过静态方式进行控制：而无法单独操控每个微透镜单元，这也帮助解释了全息漫射体无法控制光的分布和轮廓。另一方面，在工程漫射体中，每个微透镜单元形成漫射体，由其凹形纵断面和在阵列中的位置所确定。同时，为了确保漫射体不受输入光束变化的影响，并且不产生衍射效果，微透镜单元的分布是随机的，根据产生相应的光束形状函数所选取的概率分布函数来确定。因此，工程漫射体同时保留了随机与确定性漫射体的优点，从而实现高性能的光束整形功能。 Ecp]fUQK  
FRED是美国Photon Engineering 公司开发的光学工程仿真软件，其在杂散光分析中独特的算法、高效的准确性，使其与其它同类产品相比更具优势。本案例我们重点讲述如何由RPC Photonics的BSDF数据转为FRED可识别的散射数据。 /"?yB$s  
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步骤 h
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1、 在http://www.rpcphotonics.com/bsdf-data-optical-diffusers/下载并解压BSDF数据到某一文件夹下，选择“Raw data”文件。 G vMhgG=D  
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2、 将     http://fred-kb.photonengr.com/wp-content/uploads/sites/2/2015/06/constructRpcScatterFile.frs脚本文件放在步骤1中的文件下。（脚本代码放在了本文的最后） 8)HUo?/3  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 ste0:.*qb  
例如下所示： /MYl:>e>  
Sample name:  EDF-C1-56 [E<NEl*  
Merging data from file EDF-C1-56 0-0.txt ZN#mu]jC?  
Finished merging RPC data for sample EDF-C1-56 Wsya:9|  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt VA+ ?xk  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 >Lj0B%^EvM  
a. 创建一个新的散射库 _0dm?=  
b. 散射模型命名 o0nd]"q?  
c. 改变散射模型为“Tabulated BSDF”. U Hh  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） `~0)}K.F  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 ]R[j]E.  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， N\{Xhr7d  
g. 点击OK 5<ZE.'O  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 lWr=79  
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脚本代码： mh&wvT<:{  
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'#Language "WWB-COM" 1) 7n (  
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Option Explicit &iR3]FNI  
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Sub Main 1;8=,&  
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    'Cleanup $Y'}wB{pc  
    ClearOutputWindow()  %f3qCN  
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    Print "Merging RPC Photonics BSDF Data Files" }#%3y&7M7  
    SetTextColor(255,0,0) $>^DkrOd  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." q,S[[{("  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." +I~
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    SetTextColor(0,0,0) LB9D6,*t  
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    'Current directory of this script (should be the same as the text files being merged) *UL++/f  
    Dim cDir As String EHI%QT  
    cDir = MacroDir$ & "\" ,', S  

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    'Array which will be populated with the list of files to be merged C7PVJnY0  
    Dim fList() As String, curFile As String T($d3Nn1  
    GetFileList( cDir, fList ) 0QJ :  
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    Print "" 0PdeK'7  
    Print "Files found for merging:" fv@mA--  
    For Each curFile In fList zD}@QoB  
        Print Chr(9) & curFile rgq~lZ.U4K  
    Next \vg(@)$q   
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement.  Y7*8A,  
    Dim nameArray() As String, sampName As String 4)Jtc2z7Z\  
    nameArray = Split(fList(0)," 0-0.txt") au=A+  
    sampName  = nameArray(0) R:N4_4& C~  
    Print "" <O<Kf:i&c1  
    Print "Sample name: " & Chr(9) & sampName <'T:9  
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    'Open an output file and write the FRED header data @FNaCmBX  
    Dim outFile As String _\"2Mdk`]  
    outFile = cDir & sampName & "_FRED.txt" ~,YxUn8@  
    Open outFile For Output As #1 TA4>12C6  
    Print #1, "type bsdf_data" 8-#_xsZ^;  
    Print #1, "format angles=deg bsdf=value scale=1" I1f4u6\*X  
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    'Loop the file list, skip the two header lines and write the remaining data to file "aL.`^.  
    Dim lineArray() As String, curLine As Long L<D<3g|4  
    For Each curFile In fList 1`sLbPW  
        Print "Merging data from file " & curFile `GDWy^-Q+!  
        ReadFile( cDir & curFile, lineArray ) s
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        For curLine = 2 To UBound(lineArray) z:Y Z]   
            Print #1, lineArray(curLine) w]@H]>sHd  
        Next e:9s%|]T  
    Next C4[)yJ  
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    'Close the output file k2 _i;v  
    Close #1 o}4~CN9}  
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    Print "Finished merging RPC data for sample " & sampName !k3 eUBF  
    Print "FRED formatted data file: " & Chr(9) & outFile s7d4)A%  
End Sub H^3f!\MC;o  
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'Utility function to read the contents of a file into an array of strings. Q6 oM$qiM  
Function ReadFile(ByVal fileName As String, _ ohJo1}{  
                  ByRef lineArray() As String) As Long zH5
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    ReadFile = -1 d6+$[4w  
    Dim oFSO As Object +,Ud 3iS  
    Set oFSO = CreateObject("Scripting.FileSystemObject") W(jOD,QM
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    Erase lineArray WEaG/)y  
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    Dim fid As Long c80Ffq  
    If oFSO.fileexists( fileName ) Then Qx")D?u  
        fid = FreeFile() \; voBU  
        Open fileName For Input As fid T?g%I  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) {1eW*9  
        Close fid ;;|o+4Ob;  
    End If
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    Set oFSO = Nothing fsjCu!  
    Return UBound( lineArray ) ZX8AB  
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End Function M!wa }  
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Sub GetFileList( ByVal in_dir As String, _ \1He9~6  
                 ByRef in_flist() As String ) nYnBWDnV  
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    'Redimension the file list array /:;"rnvq  
    Erase in_flist aGAeRF  
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    'Tracks how many files are found @tIY%;Bgk  
    Dim fCount As Long Pihpo  
    fCount = 0 Fhrj$  
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    'Recurse directory and search for text files #|"M  
    Dim f As String 50CjH"3PZ`  
    f = Dir$(in_dir & "*.txt") qKD Nw8>  
    While f <> "" ri/CLq^D  
        ReDim Preserve in_flist(fCount) ES)@iM?5  
        in_flist(fCount) = f 5{xK&[wR*  
        fCount += 1 5m yQBK
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        f = Dir$() y 2C Jk~  
    Wend hLr\;Swyp  
    ReDim Preserve in_flist(fCount-1) udOdXz6K?  
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End Sub G3o`\4p