[技术]RPC Photonics扩散片BSDF [复制链接]

摘要： Sw-2vnSdM  
LCA+y1LP-_  
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。 S\t!7Xs%*U  
#EE<MKka  
背景： l,b,U/3R.  
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。 !XI9evJw  
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。 z4(\yx  
Wrp+B[{r\  
udr|6EjD.  
*,O3@,+>H  
步骤 <GQ=PrT|/  
iS.gN&\z^  
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。 ZK'WKC  
KOXG=P0  
)*uotV  
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） $/#[,1  
3、 打开FRED并运行脚本文件，会输出如下“<SAMPLE>_FRED.txt”格式，<SAMPLE>即为RPC Photonics散射片数据集 +=|%9%  
例如下所示： AOcUr)  
Sample name:  EDF-C1-56 i-4L{T\K  
Merging data from file EDF-C1-56 0-0.txt &vN!>bR  
Finished merging RPC data for sample EDF-C1-56 &1yErGXC  
FRED formatted data file:  D:\FRED\散射片数据\EDF-C1-56_FRED.txt ..'"kX:5  
4、 生成了FRED可识别的文件后，将散射模型导入到FRED里面 T5T[$%]6  
a. 创建一个新的散射库 :ntAU2)H  
b. 散射模型命名 Zn)o@'{}{  
c. 改变散射模型为“Tabulated BSDF”. Ujvm|ml  
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 ） LqJV  
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%]sym  
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， D[6sy`5l  
g. 点击OK wnXU=  
5、 数据输入后，可点击“Plot”按钮验证BSDF模型及总的散射值 ){,Mv:#+T  
W}zq9|p  
?-`&YfF  
脚本代码： A8S9HXL
 
(0_zp`)  
'#Language "WWB-COM" p*@t$0i  
FoZI0p?L)9  
Option Explicit j!k$SDA-  
+
`B^D  
Sub Main 0xCe6{86  
TEj"G7]1$A  
    'Cleanup pTTM(Hrx  
    ClearOutputWindow() w6mYLK%  
NzM,0q  
    Print "Merging RPC Photonics BSDF Data Files" *(]ZdB_2  
    SetTextColor(255,0,0) q?]KZ_a  
    Print "Note: Script should be located in the same folder as the BSDF TXT files." .V_5q:tu  
    Print "Note: Do not run this script multiple times without deleting the output file between executions." L 9cXgd  
    SetTextColor(0,0,0)
.Xe_Gp"x  
toOdL0hCe  
    'Current directory of this script (should be the same as the text files being merged) TMsCl6dB  
    Dim cDir As String RwrRN+&s\  
    cDir = MacroDir$ & "\" uocFOlU0n  
KV6D0~  
    'Array which will be populated with the list of files to be merged r5(efTgAd+  
    Dim fList() As String, curFile As String DZH2U+K  
    GetFileList( cDir, fList ) W.D>$R2  
WI&}94w  
    Print "" OmfHrlA  
    Print "Files found for merging:" m,]9\0GUd  
    For Each curFile In fList dShGIH?  
        Print Chr(9) & curFile  i?e
Vi  
    Next 
Ja/  
Q~' \oWz  
    'Split the first text file name found to get the sample name.  First file should be 0-0 measurement. ZUz7h^3@  
    Dim nameArray() As String, sampName As String }:J-o  
    nameArray = Split(fList(0)," 0-0.txt") r/P}j4)b7  
    sampName  = nameArray(0) \,v+ejhw  
    Print "" ^1_[UG  
    Print "Sample name: " & Chr(9) & sampName ;3bUgI}.J  
u'DpZ  
    'Open an output file and write the FRED header data _nX8f &  
    Dim outFile As String S>j.i  
    outFile = cDir & sampName & "_FRED.txt" n)35-?R/M  
    Open outFile For Output As #1 gMPp'^g]_  
    Print #1, "type bsdf_data" V 7ZGT  
    Print #1, "format angles=deg bsdf=value scale=1" Y)(yw \&v  
H ="I=}  
    'Loop the file list, skip the two header lines and write the remaining data to file I-Ut7W   
    Dim lineArray() As String, curLine As Long 9v8^uPA  
    For Each curFile In fList *uy<Om  
        Print "Merging data from file " & curFile 91q  
        ReadFile( cDir & curFile, lineArray ) d:#tN4y7(  
        For curLine = 2 To UBound(lineArray) jPZpJ:  
            Print #1, lineArray(curLine) kh#fUAt  
        Next p:0X3?IG3  
    Next zf^|H% ~^  
fYh<S  
    'Close the output file SN\c2^#  
    Close #1 Q#K10*-O6  
H?xYS| n  
    Print "Finished merging RPC data for sample " & sampName 2\T\p<_20  
    Print "FRED formatted data file: " & Chr(9) & outFile ~$"2,&  
End Sub "J+4  
CHD.b%_|  
'Utility function to read the contents of a file into an array of strings. _G25$%/LU  
Function ReadFile(ByVal fileName As String, _ 39F e#u  
                  ByRef lineArray() As String) As Long 6Q_A-X3hk  
%&V%=-O_7  
    ReadFile = -1 j4]3}t0q  
    Dim oFSO As Object Y#=MN~##t  
    Set oFSO = CreateObject("Scripting.FileSystemObject") -R\dgS3  
    Erase lineArray l~DIV$>,Z  
Cz9MXb]B  
    Dim fid As Long '
!,(G3  
    If oFSO.fileexists( fileName ) Then wArfnB&  
        fid = FreeFile() AS;qJ)JfzQ  
        Open fileName For Input As fid ijzwct#.  
        lineArray = Split(Input(LOF(fid), fid), vbCrLf) "VU/Ucb7  
        Close fid 'V&Uh]>  
    End If QgQ$>  
    Set oFSO = Nothing UEfY'%x  
    Return UBound( lineArray ) "h7Dye  
9tVV?Q@)  
End Function ={N1j<%fh  
n5^57[(  
Sub GetFileList( ByVal in_dir As String, _ #h4FLF_w  
                 ByRef in_flist() As String ) P~iZae  
p?4[nS-,  
    'Redimension the file list array dh&>

E  
    Erase in_flist eR6vO5to  
\4C[<Gbx$(  
    'Tracks how many files are found U/|JAg#  
    Dim fCount As Long Qf}.=(  
    fCount = 0 xk7Dx}  
_:p-\Oo.  
    'Recurse directory and search for text files i*@PywT"i3  
    Dim f As String L/] (pXEp  
    f = Dir$(in_dir & "*.txt") 5/7(>ivn  
    While f <> "" _nxH
;Za  
        ReDim Preserve in_flist(fCount) Q[K)Yd  
        in_flist(fCount) = f H6|eUU[&  
        fCount += 1 b(Tv
c  
        f = Dir$() cGdYfi  
    Wend d%-/U!z?  
    ReDim Preserve in_flist(fCount-1) w-LENdw  
Ot:}Ncq^\O  
End Sub z0SF2L H