[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： "+\lws  
@)-sTgn  
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。 ;GVV~.7/  
a,3j,(3  
背景： tyfTU5"x  
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。 KQ`qpX^d  
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。 \(VTt|}By$  
uMut=ja(U  
4VHqBQ4  
76wc,+  
步骤 iS&l8@2a  
dcLA1sN,  
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。 ( xXGSx  
?I/qE='*  
|X,|QC*7?  
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） 6&DX] [G  
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 $BkubWM  
例如下所示： uA,>a>xYI  
Sample name:  EDF-C1-56 cZH-"  
Merging data from file EDF-C1-56 0-0.txt zS\E/.X2  
Finished merging RPC data for sample EDF-C1-56 -:Fe7c  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt 5K^69mx  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 _ ):d`O e  
a. 创建一个新的散射库 90|7ArM_[  
b. 散射模型命名 ^Y u6w\QM
 
c. 改变散射模型为“Tabulated BSDF”. NM]s8c
K_  
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 ） BYTnrPA&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。 gzBy?r> r  
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， GiP`dtK
 
g. 点击OK !:|TdYrmj  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 TT50(_8  
A,V\"KU  
#O$  
脚本代码： JoRT&rkd  
v^)bhIPe;  
'#Language "WWB-COM" ( {1e%  
!O.[PH(,*  
Option Explicit ]?Fi$3Lm  
j<2m,~k`V  
Sub Main o;W`4S^  
o@#Y8M  
    'Cleanup S
-7'it!1  
    ClearOutputWindow() .
!1S[  
7SlsnhpW  
    Print "Merging RPC Photonics BSDF Data Files" d0aCY  
    SetTextColor(255,0,0) #VB')^d<U  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." Ma'_e=+A  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." V$"ujRp  
    SetTextColor(0,0,0) VOc8q-hK  
JYrY
[',u  
    'Current directory of this script (should be the same as the text files being merged) L
KCb_9  
    Dim cDir As String {%VV\qaC
 
    cDir = MacroDir$ & "\" hq:&wN7Q  
ZunCKc  
    'Array which will be populated with the list of files to be merged Xcrk;!IB?  
    Dim fList() As String, curFile As String L7= Q<D<  
    GetFileList( cDir, fList ) !).}u,*'no  
V?P,&c?
84  
    Print "" -b9;5eS!  
    Print "Files found for merging:" UPc<gB  
    For Each curFile In fList 1iX)d)
(b  
        Print Chr(9) & curFile 3' ~gviI  
    Next ?gO8kPg/D  
3
m>+-})d  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. Py>{t4;S  
    Dim nameArray() As String, sampName As String 3I!?e!y3(  
    nameArray = Split(fList(0)," 0-0.txt") ,h{A^[yl  
    sampName  = nameArray(0) N0K){  
    Print "" _bzqd" 31I  
    Print "Sample name: " & Chr(9) & sampName V7Z4T6j4  
]J* ,g,  
    'Open an output file and write the FRED header data 6\u!E~zy  
    Dim outFile As String L4b:F0  
    outFile = cDir & sampName & "_FRED.txt" 4-kZJ\]  
    Open outFile For Output As #1 (]RM6i7  
    Print #1, "type bsdf_data" DNR~_3Aq  
    Print #1, "format angles=deg bsdf=value scale=1" kdxz!  
nI/kw%<  
    'Loop the file list, skip the two header lines and write the remaining data to file 277ASCWLkU  
    Dim lineArray() As String, curLine As Long zF@o2<cD@  
    For Each curFile In fList s-Aw<Q)d  
        Print "Merging data from file " & curFile \":?xh_H  
        ReadFile( cDir & curFile, lineArray ) ari7iF~j  
        For curLine = 2 To UBound(lineArray) &n[~!%(  
            Print #1, lineArray(curLine) ]l@ qra  
        Next b1gaj"]  
    Next Z<#hS=eY  
a8dXH5_  
    'Close the output file { F'Kk\f%:  
    Close #1 -w;(cE  
^9_UUzf\  
    Print "Finished merging RPC data for sample " & sampName RQkyCAGx  
    Print "FRED formatted data file: " & Chr(9) & outFile 8K;Y2 #
 
End Sub LuR,f"
%2  
IcrL   
'Utility function to read the contents of a file into an array of strings. < AI;6/  
Function ReadFile(ByVal fileName As String, _ uK("<u|  
                  ByRef lineArray() As String) As Long H{?9CxY
a  
B-*E:O0y  
    ReadFile = -1 h6%[q x<  
    Dim oFSO As Object 'q>2t}KG  
    Set oFSO = CreateObject("Scripting.FileSystemObject") ExSO|g]%
 
    Erase lineArray >t
G+?Y'{  
R//$r%a  
    Dim fid As Long !)qQbk  
    If oFSO.fileexists( fileName ) Then ]WUC:6x  
        fid = FreeFile() 2/36dGFH  
        Open fileName For Input As fid w-b' LP  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) g7CXlT0Q6  
        Close fid BPqGJ7@  
    End If yMc:n"-[  
    Set oFSO = Nothing joXfmHB}  
    Return UBound( lineArray ) "BKeot[""p  
>r)X:K+I  
End Function <&pKc6+{  
`W `0Fwu9  
Sub GetFileList( ByVal in_dir As String, _ ]DvO:tM  
                 ByRef in_flist() As String ) H^~.mBP n  
K'1~^)*  
    'Redimension the file list array pi5GxDA]  
    Erase in_flist \OC6M` /  
Te{ *6-gO3  
    'Tracks how many files are found pi@Xkw  
    Dim fCount As Long E2AW7f(/  
    fCount = 0 Ogg#jx(4  
g,]
@4|  
    'Recurse directory and search for text files bm}6{28R  
    Dim f As String (QB+%2v  
    f = Dir$(in_dir & "*.txt") D);'pKl  
    While f <> "" XM|%^ry
 
        ReDim Preserve in_flist(fCount) 2UP,Tgn..  
        in_flist(fCount) = f /^#G0f*N  
        fCount += 1 2.Yi(r  
        f = Dir$() =
l942p  
    Wend rrs"N3!aT  
    ReDim Preserve in_flist(fCount-1) ekQrW%\3  
,xths3.K  
End Sub 5IqQ|/m<6