[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： lT`y=qR|  
[Pn(d[$z  
RPC Photonics公司有高品质的的工程漫射体BSDF测试数据，但它对于FRED帮助甚少，下面这个步骤描述了如何利用FRED脚本转换RPC Photonics提供的TXT文件，并将数据直接应用到FRED的Tabulated scatter 散射模型。 -tQi~Y[]  
R2]2#3`  
背景： Y|*a,H"_  
Thorlabs和RPC Photonics联手共同推出的新型漫射体及光束整形技术，可以解决其他技术的不足，大大改善了诸如光刻系统、有效固态照明，显示，背光，显示亮度增强和投影屏等大多数应用的性能。这项我们称之为工程漫射体（Engineered DiffusersTM）的新概念，与其他技术有许多不同。与诸如磨砂玻璃、乳色玻璃和全息元件等随机漫射体截然不同，工程漫射体要求对于每个散射中心，通常为微透镜单元，都进行控制。例如全息漫射体可以视为一组随机排列的透镜，但是通过全息曝光形成的类透镜效果只能通过静态方式进行控制：而无法单独操控每个微透镜单元，这也帮助解释了全息漫射体无法控制光的分布和轮廓。另一方面，在工程漫射体中，每个微透镜单元形成漫射体，由其凹形纵断面和在阵列中的位置所确定。同时，为了确保漫射体不受输入光束变化的影响，并且不产生衍射效果，微透镜单元的分布是随机的，根据产生相应的光束形状函数所选取的概率分布函数来确定。因此，工程漫射体同时保留了随机与确定性漫射体的优点，从而实现高性能的光束整形功能。 q<5AB{Oj?  
FRED是美国Photon Engineering 公司开发的光学工程仿真软件，其在杂散光分析中独特的算法、高效的准确性，使其与其它同类产品相比更具优势。本案例我们重点讲述如何由RPC Photonics的BSDF数据转为FRED可识别的散射数据。 ;y"=3-=vM"  
**oaR  
fyRSg B00$  
-E*VF{IG1  
步骤 qy]tuKZI  
K *<+K<Tp  
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。 EWcqMD]4u  
4,nUCT  
2Hh5gD|>  
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） 7GY3_`  
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 RDX$Wy$@L  
例如下所示： n54}WGo>9  
Sample name:  EDF-C1-56 OA_WjTwDs  
Merging data from file EDF-C1-56 0-0.txt w1#1s|  
Finished merging RPC data for sample EDF-C1-56 NCid`a$  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt Ng1{NI+S  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 2{-};
 
a. 创建一个新的散射库 !foiGZ3g  
b. 散射模型命名 |%V-|\GJ~j  
c. 改变散射模型为“Tabulated BSDF”. n86=1G:%  
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 ） e-4 Qw#cw  
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。 lQkCA-  
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， r5k{mV+  
g. 点击OK fz9 ,p;b  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 &l&B[s6[  
<k41j=d  
h(<2{%j  
脚本代码： WbIf)\  
;J]
Lzh  
'#Language "WWB-COM" +!@@55I-  
q_J)68BR  
Option Explicit sI&|qK-(  
AW6"1(D  
Sub Main 2. t'!uwI  
i]8+JG6  
    'Cleanup _?aI/D  
    ClearOutputWindow() p7Q}xx  
rV5QKz6'  
    Print "Merging RPC Photonics BSDF Data Files" BEfP#h=hr  
    SetTextColor(255,0,0) xE0'eC5n^  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." @xqjAcfg  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." B%L dH  
    SetTextColor(0,0,0) (8XP7c]5  
eHIsTL@Fp  
    'Current directory of this script (should be the same as the text files being merged) gq:2`W&5  
    Dim cDir As String ^U5g7Emf  
    cDir = MacroDir$ & "\" ?'jRUfl   
Xy[*)<  
    'Array which will be populated with the list of files to be merged [f8mh88r  
    Dim fList() As String, curFile As String 3-%F)@n  
    GetFileList( cDir, fList ) Qf$3!O}G  
<$:Hf@tpMo  
    Print "" -9X#+-  
    Print "Files found for merging:" zCuN8  
    For Each curFile In fList &_Vd  
        Print Chr(9) & curFile #P^cR_|\  
    Next FN>ns,  
H
OY@<'  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. W "}Cfv  
    Dim nameArray() As String, sampName As String ]ssX,1#Xh  
    nameArray = Split(fList(0)," 0-0.txt") 9_/dj"5
 
    sampName  = nameArray(0) S0zk<S  
    Print "" $bho]~  
    Print "Sample name: " & Chr(9) & sampName HOPi2nf{  
|B` mWZ'"  
    'Open an output file and write the FRED header data U6sPJc<  
    Dim outFile As String 5@3hb]J  
    outFile = cDir & sampName & "_FRED.txt" $={^':Uh  
    Open outFile For Output As #1 =D}]
|ie  
    Print #1, "type bsdf_data" l`V^d  
    Print #1, "format angles=deg bsdf=value scale=1" eGEeWJ}[$  
BQ /0z^A  
    'Loop the file list, skip the two header lines and write the remaining data to file aN,.pLe;  
    Dim lineArray() As String, curLine As Long & 6-8$  
    For Each curFile In fList {i!@C(M3  
        Print "Merging data from file " & curFile kbR!iPM-;  
        ReadFile( cDir & curFile, lineArray ) |GqKa  
        For curLine = 2 To UBound(lineArray) {CVn&|}J  
            Print #1, lineArray(curLine) RY\[[eG  
        Next V39`J*fI  
    Next 6.0/asN}  
nUy2)CL[L  
    'Close the output file ' Akt5q  
    Close #1 `{ 6K~(  
Ug=)_~  
    Print "Finished merging RPC data for sample " & sampName u@ psVt   
    Print "FRED formatted data file: " & Chr(9) & outFile +kdZfv>  
End Sub Q9C;_Up  
fMSB  
'Utility function to read the contents of a file into an array of strings. S@WzvM  
Function ReadFile(ByVal fileName As String, _ YS|Ve*t(L=  
                  ByRef lineArray() As String) As Long q<2b,w==  
tXu_o6]  
    ReadFile = -1 rF>7 >wq  
    Dim oFSO As Object z}sBx9;  
    Set oFSO = CreateObject("Scripting.FileSystemObject") B?|url6h  
    Erase lineArray Pm}
 
*(pmFEc
 
    Dim fid As Long G|,'6|$jE  
    If oFSO.fileexists( fileName ) Then 8`?vWJS  
        fid = FreeFile() _1sjsGp>  
        Open fileName For Input As fid ~UhTy~jya  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) 2uajK..b  
        Close fid 1TIP23:  
    End If s+jL BY  
    Set oFSO = Nothing bFt$u]Yvo  
    Return UBound( lineArray ) v? VNWK2  
{ :~&#D  
End Function 5[\LQtM  
h,u?3}Knnb  
Sub GetFileList( ByVal in_dir As String, _ {:!CA/0Jx  
                 ByRef in_flist() As String ) teDO,
$  
8E:d!?<^&I  
    'Redimension the file list array F\"`^`(O  
    Erase in_flist Bf-KCqC".  
l^,"^vz  
    'Tracks how many files are found 'A}@XGE:p  
    Dim fCount As Long p\&Lbuzv  
    fCount = 0 O,+ZD^  
P+j5_V{\b  
    'Recurse directory and search for text files <JyF5  
    Dim f As String [ {|868  
    f = Dir$(in_dir & "*.txt") F]4JemSjK  
    While f <> "" iXJ3B&x  
        ReDim Preserve in_flist(fCount) &qO#EEqG]  
        in_flist(fCount) = f JJ=%\j  
        fCount += 1 UOwEA9q%  
        f = Dir$() +l8`oQuG  
    Wend JPq2C\Ka  
    ReDim Preserve in_flist(fCount-1) q0a8=o"|  
$QB~ x{v@n  
End Sub >#[u"CB