[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： XabrX|B#  
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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。 G\H@lFh  
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背景： 9CWUhS   
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。 =P
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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。 w I@ lO\  
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步骤 *0R=(Gy  
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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。 Z3R..vy
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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） o0wep&@  
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 7@DinA!  
例如下所示： T"Q4vk,3*J  
Sample name:  EDF-C1-56 BsB}noN}  
Merging data from file EDF-C1-56 0-0.txt "MXd!  
Finished merging RPC data for sample EDF-C1-56 xsFWF*HPs  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt h3p 3~xq  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 zPV/{)S  
a. 创建一个新的散射库 7B%@f9g  
b. 散射模型命名 ~ilbW|s?=k  
c. 改变散射模型为“Tabulated BSDF”. O|j5ulO}&"  
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 ） =WEfo;  
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。 BJj~fNm1Zr  
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， /,0t,"&Aqa  
g. 点击OK @-b}iP<T  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 jd2Fh):q  
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脚本代码： u>S&?X'a  
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'#Language "WWB-COM" iMp)g%Ng  
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Option Explicit t41c
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Sub Main 5Ij_$a  
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    'Cleanup 1C$^S]v%a  
    ClearOutputWindow() Z^fF^3x  
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    Print "Merging RPC Photonics BSDF Data Files" "4tRy9q  
    SetTextColor(255,0,0) //+
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    Print "Note: Script should be located in the same folder as the BSDF TXT files." Z@ws,f^e  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." ~4`wfOvO  
    SetTextColor(0,0,0) ,+X8?9v  
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    'Current directory of this script (should be the same as the text files being merged) iqoPD4A  
    Dim cDir As String OC>" +  
    cDir = MacroDir$ & "\" ]owH [wvX  
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    'Array which will be populated with the list of files to be merged sG VC+!E  
    Dim fList() As String, curFile As String e8lF$[i  
    GetFileList( cDir, fList ) 95!xTf  
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    Print "" 5;^8wh(  
    Print "Files found for merging:" 8Peqm?{5Y5  
    For Each curFile In fList }dXL= ul  
        Print Chr(9) & curFile ttw@nv% @  
    Next |;_ yAL  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. tRv#%>fj  
    Dim nameArray() As String, sampName As String ]
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    nameArray = Split(fList(0)," 0-0.txt") =;{S>P!I(t  
    sampName  = nameArray(0) Z?x]HB`r  
    Print "" 2)8lJXM$L  
    Print "Sample name: " & Chr(9) & sampName u51/B:+  
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    'Open an output file and write the FRED header data $o
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    Dim outFile As String Rp<Xu6r  
    outFile = cDir & sampName & "_FRED.txt" =[k9{cVW  
    Open outFile For Output As #1 =az$WRV+7!  
    Print #1, "type bsdf_data" SA&wW\Ym]  
    Print #1, "format angles=deg bsdf=value scale=1" Sph+kiy|  
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    'Loop the file list, skip the two header lines and write the remaining data to file >'T%=50YH  
    Dim lineArray() As String, curLine As Long K7l{&2>?  
    For Each curFile In fList ?eO|s5r  
        Print "Merging data from file " & curFile 1Jd:%+T  
        ReadFile( cDir & curFile, lineArray ) lR(&Wc\j  
        For curLine = 2 To UBound(lineArray) f*
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            Print #1, lineArray(curLine) *= 71/&B  
        Next CeJ|z{F\  
    Next E7<:>Uh  
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    'Close the output file #X8[g_d
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    Close #1 4J_%quxO  
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    Print "Finished merging RPC data for sample " & sampName 'I~dJEW7  
    Print "FRED formatted data file: " & Chr(9) & outFile H xlw1(zS  
End Sub 9C.cz\E  
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'Utility function to read the contents of a file into an array of strings. 96.Wfx  
Function ReadFile(ByVal fileName As String, _ d;^?6V  
                  ByRef lineArray() As String) As Long O92Yd$S  
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    ReadFile = -1 ,J^Op   
    Dim oFSO As Object 6vA5L_  
    Set oFSO = CreateObject("Scripting.FileSystemObject") q-Qws0\v.  
    Erase lineArray <(MFEIt  
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    Dim fid As Long P2p^
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    If oFSO.fileexists( fileName ) Then _e3'f:  
        fid = FreeFile() -^5R51  
        Open fileName For Input As fid hmH
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        lineArray = Split(Input(LOF(fid), fid), vbCrLf) )yP>}ME  
        Close fid g)9/z  
    End If M<)2  
    Set oFSO = Nothing US|vYd}u+  
    Return UBound( lineArray ) r
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End Function K)?^
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Sub GetFileList( ByVal in_dir As String, _ 6&Dvp1`m  
                 ByRef in_flist() As String ) ,gvX
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    'Redimension the file list array 2z\F m/Z.  
    Erase in_flist #+;=ijyF  
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    'Tracks how many files are found B<LavX>F  
    Dim fCount As Long DX";v J  
    fCount = 0 IT(c'}  
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    'Recurse directory and search for text files n@Ag`}  
    Dim f As String  vt N5{C  
    f = Dir$(in_dir & "*.txt") qM0MSwvC=  
    While f <> "" arP+(1U  
        ReDim Preserve in_flist(fCount) 1Q5<6*QL"  
        in_flist(fCount) = f (UZ*36@PJx  
        fCount += 1 L\ %_<2  
        f = Dir$() ~@8d[Tb  
    Wend 4AYc8Z#'  
    ReDim Preserve in_flist(fCount-1) .;b
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End Sub 6bcrPf}