[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： 6ll!7U(9(  
01r%K@ xX\  
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。 [=K lDfU=  
&M13F>!  
背景： 6H|1IrG  
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。 S;4:`?s=i  
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。 i$NlS}W  
J*;RL`  
Z"8lW+r*  
,@ '^3u  
步骤 9n
R\7!_  
[xqV`(vM  
1、 在http://www.rpcphotonics.com/bsdf-data-optical-diffusers/下载并解压BSDF数据到某一文件夹下，选择“Raw data”文件。 ZJ3g,dc  
A-!e$yz>  
7ws<' d7/  
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） #8Bh5L!SJ1  
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 ~nA k-toJ  
例如下所示： *2h%dT:,%  
Sample name:  EDF-C1-56 ht
tywa^  
Merging data from file EDF-C1-56 0-0.txt }Ulxt:}   
Finished merging RPC data for sample EDF-C1-56 :8`A  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt 1'&.6{)P  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 IR-n:z  
a. 创建一个新的散射库 [lzd'  
b. 散射模型命名 g<Z :`00|  
c. 改变散射模型为“Tabulated BSDF”. $7q3[skH  
d. 在File框出右键选择“Replace With Data From a File”, 选择步骤三生成的数据文件（如EDF-C1-56_FRED.txt ） "<iH8Mz
Z  
e. 切换为“Varies w/angle” 选项（假定所有的RPC Photonics datasets 数据有多个测试角度。 s!IIvF  
f. 在底部的对话框中，选择透射散射、反射停并且你需要终止入射光线， 4Fg2/O_3  
g. 点击OK b6-N2F1Fs  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 Yc7YNC.  
A|ZT;\  
-`faXFW'  
脚本代码： *D|a`R!Y  
7${<u0((!  
'#Language "WWB-COM" `G$>T#Dq  
h ;*x1BVE  
Option Explicit RBQ8+^  
6=f)3!=  
Sub Main .lcp5D[(  
x0# Bc7y  
    'Cleanup 19$A!kH\  
    ClearOutputWindow() pA!-sp
gX  
rg^\gE6_  
    Print "Merging RPC Photonics BSDF Data Files" c!\Gj|  
    SetTextColor(255,0,0) ]?}>D?5  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." @_do<'a  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." JVoC2Z<  
    SetTextColor(0,0,0) uU^DYgs  
<@Q27oEuA  
    'Current directory of this script (should be the same as the text files being merged) HTL6;87w+]  
    Dim cDir As String &qbEF3p^@  
    cDir = MacroDir$ & "\" it}h8:^<  
%Xh}{o$G  
    'Array which will be populated with the list of files to be merged
]o'o v
 
    Dim fList() As String, curFile As String 9VW/Af  
    GetFileList( cDir, fList ) e* [wF}))  
BdD]HXB|_  
    Print "" -m^-p  
    Print "Files found for merging:" <1*kXTN(  
    For Each curFile In fList E^)FnXe5  
        Print Chr(9) & curFile Z:{| ?4  
    Next `Abd=1nH  
,SIS
3A>s  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. 9G[ DuYJI  
    Dim nameArray() As String, sampName As String k7U.]#5V  
    nameArray = Split(fList(0)," 0-0.txt") IP`lx  
    sampName  = nameArray(0) <N)!s&D  
    Print "" Z=&|__+d  
    Print "Sample name: " & Chr(9) & sampName ^os_j39N9  
as@8L|i*  
    'Open an output file and write the FRED header data 1WtE
] D  
    Dim outFile As String Q^ W,)%  
    outFile = cDir & sampName & "_FRED.txt" <,:{Q75
  
    Open outFile For Output As #1 :u7BCV|yr  
    Print #1, "type bsdf_data" Ts.2\-+3  
    Print #1, "format angles=deg bsdf=value scale=1" DZqG7p$u4i  
no+m.B  
    'Loop the file list, skip the two header lines and write the remaining data to file l9\W=-'  
    Dim lineArray() As String, curLine As Long @@H/q  
    For Each curFile In fList h3 HUdu  
        Print "Merging data from file " & curFile o<5`uV!f  
        ReadFile( cDir & curFile, lineArray ) .'`aX 7{\  
        For curLine = 2 To UBound(lineArray) 2q[pOT'k  
            Print #1, lineArray(curLine) My>q%lF=fw  
        Next 48-j  
    Next %1 )c{7  
43k'96[2d  
    'Close the output file pE
wo}NS*H  
    Close #1 2{j$1EdI@-  
45 ^ Z5t  
    Print "Finished merging RPC data for sample " & sampName vN(~}gOd\  
    Print "FRED formatted data file: " & Chr(9) & outFile >T;!Z5L1  
End Sub y^H5iB[SPL  
N7s0Ua'-v  
'Utility function to read the contents of a file into an array of strings. IFBt#]l0  
Function ReadFile(ByVal fileName As String, _ <Z.`X7]Uk  
                  ByRef lineArray() As String) As Long .'=S1|_(  
d*tWFr|J-  
    ReadFile = -1 vP,pK=5  
    Dim oFSO As Object N~]qQoj,  
    Set oFSO = CreateObject("Scripting.FileSystemObject") w!"A$+~  
    Erase lineArray :? )!yI  
L-- t(G  
    Dim fid As Long 9<3( QR  
    If oFSO.fileexists( fileName ) Then $*eYiz3Ue  
        fid = FreeFile() f2c<-}wR  
        Open fileName For Input As fid F9LKO3Rh#u  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) 5:r AWq  
        Close fid 
U LS>v  
    End If {-I+  
    Set oFSO = Nothing <6;M\:Y*T  
    Return UBound( lineArray ) C]Fw*t   
oU)(/  
End Function G$a@}9V  
; s(bd#Q  
Sub GetFileList( ByVal in_dir As String, _ v9H t~\>  
                 ByRef in_flist() As String ) A!GvfmzqIn  
9iT9ZfaW  
    'Redimension the file list array }-:B`:K&  
    Erase in_flist (LsVd2Ab
R  
4Yvz-aSyO  
    'Tracks how many files are found 9U;  
    Dim fCount As Long .=YV  
    fCount = 0 zx<t{e7  
T%.Yso{  
    'Recurse directory and search for text files =p@2[Uo  
    Dim f As String jS]Saqd  
    f = Dir$(in_dir & "*.txt") 8\;, d  
    While f <> "" 9wCgJ$te  
        ReDim Preserve in_flist(fCount) k% \;$u=%  
        in_flist(fCount) = f g<;pyvq|:  
        fCount += 1 *JImP9SE  
        f = Dir$() 3]1 !g6  
    Wend +E9G"Z65iP  
    ReDim Preserve in_flist(fCount-1) W'9{2h6u(  
Oa:C'M b  
End Sub  gwIR3u