[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： bO2s'!x  
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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。 /degBL+  
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背景： ':jsCeSB  
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。 i^zncDMA  
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。 @ZUrr_|  
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步骤 ;@R=CQ6  
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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。 {+V]saYP  
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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） -4!9cE  
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 8UahoNrSt  
例如下所示： =KctAR;  
Sample name:  EDF-C1-56 l9eCsVQ~V  
Merging data from file EDF-C1-56 0-0.txt c4'k-\JvT  
Finished merging RPC data for sample EDF-C1-56 BlrZ<\-/  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt h/a|-V}m&  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 --}5%6  
a. 创建一个新的散射库 s.p4+KJ  
b. 散射模型命名 n8dJ6"L<"  
c. 改变散射模型为“Tabulated BSDF”. #2~-I  
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 ） AsOkOS3  
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。 -J<{NF  
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， p]-\\o}  
g. 点击OK ,sqxxq  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 vTdJe  
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脚本代码： c :{#
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'#Language "WWB-COM" Mt93YD-2+  
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Option Explicit TJY [s-
 
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Sub Main 8NJxtT~0c~  
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    'Cleanup XJ3p<  
    ClearOutputWindow() FZ0wtS2  
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    Print "Merging RPC Photonics BSDF Data Files" `v|w&ty*  
    SetTextColor(255,0,0) N-9Vx#i  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." 3;hztCZj  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." nN]G
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    SetTextColor(0,0,0)
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    'Current directory of this script (should be the same as the text files being merged) :Q=
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    Dim cDir As String UCz\SZ{za  
    cDir = MacroDir$ & "\" a At<36{?  
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    'Array which will be populated with the list of files to be merged qq,#bRe  
    Dim fList() As String, curFile As String *:
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    GetFileList( cDir, fList ) %tOGs80_{  
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    Print "" D["~G v  
    Print "Files found for merging:" RI[=N:C^  
    For Each curFile In fList .T63:  
        Print Chr(9) & curFile aJ{-m@/5  
    Next .yF@Ow  
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    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. /Z?$!u4I  
    Dim nameArray() As String, sampName As String sYG:\>}ie  
    nameArray = Split(fList(0)," 0-0.txt") L/Ytkag  
    sampName  = nameArray(0) wOLDHg_  
    Print "" 0'QX*xfa>  
    Print "Sample name: " & Chr(9) & sampName GI[TD?s  
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    'Open an output file and write the FRED header data (\8~W*ej"  
    Dim outFile As String A5\00O~  
    outFile = cDir & sampName & "_FRED.txt" 4!</JZX~$  
    Open outFile For Output As #1 :Rftn6!  
    Print #1, "type bsdf_data" cS2PrsUx  
    Print #1, "format angles=deg bsdf=value scale=1" nr{#Krkb  
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    'Loop the file list, skip the two header lines and write the remaining data to file )-s9CWJv  
    Dim lineArray() As String, curLine As Long
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    For Each curFile In fList `B A'a" $  
        Print "Merging data from file " & curFile u^4$<fd  
        ReadFile( cDir & curFile, lineArray ) &}y?Lt  
        For curLine = 2 To UBound(lineArray) X3dXRDB'  
            Print #1, lineArray(curLine) 1o8C4?T&  
        Next #lY_XV.  
    Next 3T= ?!|e  
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    'Close the output file Ct<]('Hm(  
    Close #1 B4Fuvi  
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    Print "Finished merging RPC data for sample " & sampName WR<?_X_  
    Print "FRED formatted data file: " & Chr(9) & outFile -\9K'8 C  
End Sub +7KRoF|  
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'Utility function to read the contents of a file into an array of strings. A/c#2  
Function ReadFile(ByVal fileName As String, _ E~y(@72)  
                  ByRef lineArray() As String) As Long L[cP2X]NQ  
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    ReadFile = -1 \:m1{+l  
    Dim oFSO As Object {6tj$&\)  
    Set oFSO = CreateObject("Scripting.FileSystemObject") 'n
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    Erase lineArray {z
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    Dim fid As Long xjy(f~'  
    If oFSO.fileexists( fileName ) Then rk-GQ#SKU  
        fid = FreeFile() sW,JnR  
        Open fileName For Input As fid W>j@E|m$  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) sxn{uRF  
        Close fid #I"s{*  
    End If -hY@r 7y  
    Set oFSO = Nothing `oU|U!|  
    Return UBound( lineArray ) 5~[m]   
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End Function |JLXgwML  
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Sub GetFileList( ByVal in_dir As String, _ x^79s_h5  
                 ByRef in_flist() As String ) {[)n<.n[g  
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    'Redimension the file list array ;O
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    Erase in_flist eBWgAf.k  
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    'Tracks how many files are found ,rS?^"h9  
    Dim fCount As Long :2.<JUDM  
    fCount = 0 E1`TQA  
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    'Recurse directory and search for text files v&qL r+_7  
    Dim f As String  :Y Ki  
    f = Dir$(in_dir & "*.txt") SJ2l6  
    While f <> "" $Jo4n>/  
        ReDim Preserve in_flist(fCount)  tE#;$Ss  
        in_flist(fCount) = f kMx)G]  
        fCount += 1 3yrb7Rn3  
        f = Dir$() aka)#0l .  
    Wend P~M[i9 V  
    ReDim Preserve in_flist(fCount-1) f_2(`T#  
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End Sub v5\5:b{/