[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： 21.YO]Et  
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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。 {@Blj3;w}  
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背景： -0A@
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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。 b0r,h)R  
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。 n (OjjRm  
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步骤 ,)Yao;Cvd  
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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。 c}YJqhk0J  
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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） 60~v t04  
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 uEBQo
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例如下所示： 5kK=S  
Sample name:  EDF-C1-56 ^/G?QR  
Merging data from file EDF-C1-56 0-0.txt |c<XSX?ir  
Finished merging RPC data for sample EDF-C1-56 7^c2e*S  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt g+:$X- r  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 OlIT|bzkb  
a. 创建一个新的散射库 6(:)otz  
b. 散射模型命名 4DvdEt  
c. 改变散射模型为“Tabulated BSDF”. OMl8 a B9  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） Tsu\oJ[  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 CP}0Ri)  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， DKR<W.!*t  
g. 点击OK P~&O4['<  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 Gj6<s./  
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脚本代码： yxqTm%?y  
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'#Language "WWB-COM" Xe)Pg)J1  
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Option Explicit {>S4#^@}  
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Sub Main y*_K=}pk  
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    'Cleanup 6!@0VI&P  
    ClearOutputWindow() O)l%OOv   
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    Print "Merging RPC Photonics BSDF Data Files" Lg8]dBXu  
    SetTextColor(255,0,0)  KvGbDG  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." %@>YNPD`E  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." DQcWq'yY^  
    SetTextColor(0,0,0) /\~l1.6`  
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    'Current directory of this script (should be the same as the text files being merged) S=4R5igrC  
    Dim cDir As String ?b
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    cDir = MacroDir$ & "\"  j|ozGO  
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    'Array which will be populated with the list of files to be merged U8E0~[y'  
    Dim fList() As String, curFile As String !`Le`c  
    GetFileList( cDir, fList ) r;9z5'  
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    Print "" ZH% we  
    Print "Files found for merging:" Dp^95V@  
    For Each curFile In fList ^[0"vtb  
        Print Chr(9) & curFile Vw7WK  
    Next iW'_R{)T  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. UBa-  
    Dim nameArray() As String, sampName As String ci;&CHa  
    nameArray = Split(fList(0)," 0-0.txt") ,eDu$8J9  
    sampName  = nameArray(0) ad9EG#mD#  
    Print "" Bf/|{@  
    Print "Sample name: " & Chr(9) & sampName ekrBNDs9  
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    'Open an output file and write the FRED header data z[*zuo  
    Dim outFile As String gbJG`zC>U  
    outFile = cDir & sampName & "_FRED.txt" RTZ:U@  
    Open outFile For Output As #1 (,shiK[5f  
    Print #1, "type bsdf_data" %Or2iuO%-,  
    Print #1, "format angles=deg bsdf=value scale=1" JfSdUWxT  
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    'Loop the file list, skip the two header lines and write the remaining data to file |ebvx?\  
    Dim lineArray() As String, curLine As Long
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    For Each curFile In fList 2HSb.&7-G  
        Print "Merging data from file " & curFile ?H<~ac2e  
        ReadFile( cDir & curFile, lineArray ) M= atls  
        For curLine = 2 To UBound(lineArray) 6oYIQ'hc  
            Print #1, lineArray(curLine) uQWp+}>ZJy  
        Next %iX/y  
    Next (xbIUz.  
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    'Close the output file ;|;iCaD a+  
    Close #1 {-J:4*`  
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    Print "Finished merging RPC data for sample " & sampName Q4=|@|U0  
    Print "FRED formatted data file: " & Chr(9) & outFile 9Eu #lV  
End Sub xuF5/(__  
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'Utility function to read the contents of a file into an array of strings. Rh[Ibm56  
Function ReadFile(ByVal fileName As String, _ ">cqt>2 A  
                  ByRef lineArray() As String) As Long QTfu:m{  
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    ReadFile = -1 wW^Zb
 
    Dim oFSO As Object XO%~6Us^  
    Set oFSO = CreateObject("Scripting.FileSystemObject") i0iez9B  
    Erase lineArray I.-v?1>,  
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    Dim fid As Long Ajg\aof0{  
    If oFSO.fileexists( fileName ) Then <$Ztik1  
        fid = FreeFile() (2d3jQN`  
        Open fileName For Input As fid 1g~y]iQ  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) z|Ap\[GS  
        Close fid R2CQXhiJ  
    End If <&6u]uKrW  
    Set oFSO = Nothing viJJ e'\2  
    Return UBound( lineArray ) BW>5?0E[4(  
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End Function HgaZbb>'  
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Sub GetFileList( ByVal in_dir As String, _ ;$z7[+M  
                 ByRef in_flist() As String )
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    'Redimension the file list array &kiF/F 1  
    Erase in_flist EavX8r  
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    'Tracks how many files are found bs BZE  
    Dim fCount As Long bQ"N ;d)e  
    fCount = 0 K?[)E3  
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    'Recurse directory and search for text files `zY!`G  
    Dim f As String [g`,AmR\!  
    f = Dir$(in_dir & "*.txt") %E aE,  
    While f <> "" d@Q][7  
        ReDim Preserve in_flist(fCount) 7OE[RX8!f  
        in_flist(fCount) = f M7vj^mt?
 
        fCount += 1 HitAc8  
        f = Dir$() /K@$#x_{  
    Wend ZtR&wk  
    ReDim Preserve in_flist(fCount-1) ||XIWKF<n2  

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End Sub ~{P:sjsU