[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： ] o tjoM  
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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。 
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背景： mf6?8!O}>  
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。 .2/(G{}U  
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。 X0J@c "%0  
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步骤 m `~/]QQ  
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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。 +Sv`23G@  
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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） #ebT$hf30  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 KB <n
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例如下所示： Fh9`8  
Sample name:  EDF-C1-56 6tB-  
Merging data from file EDF-C1-56 0-0.txt dQ@e+u5  
Finished merging RPC data for sample EDF-C1-56 &e@2zfl7  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt bVSa}&*kM  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 1u75  
a. 创建一个新的散射库 J/8aDr(+  
b. 散射模型命名 )Xg,;^  
c. 改变散射模型为“Tabulated BSDF”. /lkIbmV  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） )VQ:L:1t(  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 &N GYV  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， S:/;|D
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g. 点击OK E9HA8  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 %ribxgmd  
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脚本代码： GJai!$v  
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'#Language "WWB-COM" k-xh-&  
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Option Explicit u*Z>&]W_  
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Sub Main } *|_P  
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    'Cleanup Q ,30  
    ClearOutputWindow() 87c7p=/0`  
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    Print "Merging RPC Photonics BSDF Data Files" DxR__  
    SetTextColor(255,0,0) z kQV$n{  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." _HX1E  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." _O2},9L n  
    SetTextColor(0,0,0) ~4y&]:I  
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    'Current directory of this script (should be the same as the text files being merged) I!&|L0Qq  
    Dim cDir As String ,@jRe&6  
    cDir = MacroDir$ & "\" wV-1B\m  
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    'Array which will be populated with the list of files to be merged ]3wg-p+  
    Dim fList() As String, curFile As String /"+YE&>\  
    GetFileList( cDir, fList ) f9u^/QVS&  
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    Print "" v]\io# 
 
    Print "Files found for merging:" I1yZ7QY  
    For Each curFile In fList 2Un~Iy  
        Print Chr(9) & curFile 2ikY
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    Next !c[(#g  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. xr+K: bw  
    Dim nameArray() As String, sampName As String }Iz'#I Xx  
    nameArray = Split(fList(0)," 0-0.txt") |>@Gbgw^M  
    sampName  = nameArray(0) )kR~|Yn<-  
    Print "" {%5k1,/(  
    Print "Sample name: " & Chr(9) & sampName $7eO33Bm  
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    'Open an output file and write the FRED header data W#87T_7T[  
    Dim outFile As String ]C_g:|q  
    outFile = cDir & sampName & "_FRED.txt" S453oG"  
    Open outFile For Output As #1 Wm$(b2t  
    Print #1, "type bsdf_data" 90L,.  
    Print #1, "format angles=deg bsdf=value scale=1" QEK,mc3  
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    'Loop the file list, skip the two header lines and write the remaining data to file {E1g+><  
    Dim lineArray() As String, curLine As Long rTYDa3  
    For Each curFile In fList s `fIeP  
        Print "Merging data from file " & curFile ;cd{+0  
        ReadFile( cDir & curFile, lineArray ) 4of3#M  
        For curLine = 2 To UBound(lineArray) |6w.m<p  
            Print #1, lineArray(curLine) :W(3<D7\  
        Next vKN"o* q  
    Next RFd.L@-]  
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    'Close the output file yE[ -@3v  
    Close #1 h1@|UxaE#  
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    Print "Finished merging RPC data for sample " & sampName 6}wXNTd  
    Print "FRED formatted data file: " & Chr(9) & outFile w^MU$ubx  
End Sub j_S///  
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'Utility function to read the contents of a file into an array of strings. ?#?[6t  
Function ReadFile(ByVal fileName As String, _ ktLXL;~X  
                  ByRef lineArray() As String) As Long <Z5ak4P  
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    ReadFile = -1 }YJ(|z""  
    Dim oFSO As Object !]1X0wo\  
    Set oFSO = CreateObject("Scripting.FileSystemObject") g*C&Pr3  
    Erase lineArray cnr&%-  
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    Dim fid As Long  }rf_:  
    If oFSO.fileexists( fileName ) Then 6Ug(J$Ouh  
        fid = FreeFile() RN\4y{@  
        Open fileName For Input As fid  ^ZnlWZ@r  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) u4TU"r("A  
        Close fid 6*,'A|t?y  
    End If -5,QrMM<  
    Set oFSO = Nothing V\^rs41$;  
    Return UBound( lineArray ) w"d~R   
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End Function >B(%$jG Z  
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Sub GetFileList( ByVal in_dir As String, _ #g[jwl'  
                 ByRef in_flist() As String ) &No6k~T0:b  
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    'Redimension the file list array a@`15O:  
    Erase in_flist L6`(YX.:  
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    'Tracks how many files are found Jj+|>(P  
    Dim fCount As Long usEdp  
    fCount = 0 cF!ygz//  
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    'Recurse directory and search for text files J'^H@L/E  
    Dim f As String Kp?):6  
    f = Dir$(in_dir & "*.txt") USfpCRj9  
    While f <> "" +F3@-A  
        ReDim Preserve in_flist(fCount) MGpP'G:
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        in_flist(fCount) = f hZNS$  
        fCount += 1 B:S/ ?v  
        f = Dir$()  O\y#|=d  
    Wend ;;rEv5 /  
    ReDim Preserve in_flist(fCount-1) HqNM31)  
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End Sub SA_5..