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Screensize: 640 x 480 800 x 600 1024 x 768 1280 x 1024 UserName: Password: Anti-Spam Code: Format Mode: Basic  Help  Prompt  Format: Font Andale Mono Arial Arial Black Book Antiqua Century Gothic Comic Sans MS Courier New Georgia Impact Lucida Console Script MT Bold Stencil Tahoma Times New Roman Trebuchet MS Verdana   Size 1 2 3 4 5 6   Color Black Red Yellow Pink Green Orange Purple Blue Beige Brown Teal Navy Maroon LimeGreen Message: * HTML is OFF * Forum Code is ON Smilies [quote][i]Originally posted by upconverted[/i] [br]Origin Ver. and Service Release (Select Help-->About Origin): Origin 9.1, Origin 2016 Operating System: Windows 7 In relation to the CIE diagram template in the File Exchange http://www.originlab.com/fileexchange/details.aspx?fid=168 As the comment/rating system does not allow too much text, my step-by-step advice on generating CIE xy coordinates got truncated. Here it is in full form, I hope you find it helpful (and not insulting your intelligence [:D] - I just tried to make it as helpful as possible regardless of one's experience in the field, so sometimes it sounds way too descriptive): This is a wonderful template, and it works like a charm. As suggested, your own (x,y) coordinates can be inserted in either the I(X5) and J(Y5) (CIE1931) or N(X7) and O(Y7) columns. You can also add your own two columns into the sheet and using the Plot Setup options of the selected CIE template graph you can add your points as a scatter plot to the graph. I prefer the second option, as it doesn't require to change anything in the I,J,N,O columns, which are basically used not for the presentation of desired points on the chromaticity graphs, but for governing the numerical labels (480, 540, etc.) on the boundary line, and that's why symbol size is set to 0. So this second option (adding own columns and own layer with a new scatter plot) is less invasive and leaves the template unchanged. For calculation of the (x,y) coordinates in the CIE1931 system, you have to use the three color matching functions established in the CIE 1931 norm. They are available in many sources throughout the Internet, and I find them quite simple from the mathematical point of view (not too complicated, just continous distributions with almost no distortions in their shape) and for my own use I have approximated them with Gaussian peaks with a very good quality of fit. That way, I do not have to extrapolate/interpolate the functions every time I need to use them on spectra coming from different detectors with different setpoints in the wavelengths, I just paste the mathematical formula of the fitted Gauss peaks in the "F(x)" field (or in the Set Column Values pop-up window). If you have the Wavelength values as the first column in the sheet containing your spectrum/spectra (which is usually true), their formulas are as follows: - the R (red) matching function is given as: (6,79019/(24,93847*sqrt(PI/2)))*exp(-2*((Col(A)-426,43824)/24,93847)^2) + (6,1217/(20,58198*sqrt(PI/2)))*exp(-2*((Col(A)-444,98226)/20,58198)^2) + (5,26417/(22,91681*sqrt(PI/2)))*exp(-2*((Col(A)-465,42598)/22,91681)^2) + (6,23927/(34,04001*sqrt(PI/2)))*exp(-2*((Col(A)-546,85313)/34,04001)^2) + (86,12739/(60,45446*sqrt(PI/2)))*exp(-2*((Col(A)-598,63324)/60,45446)^2) + (3,09919/(76,0973*sqrt(PI/2)))*exp(-2*((Col(A)-638,40519)/76,0973)^2) - for G it is: 2,23003E-4 + (2,77642/(41,57301*sqrt(PI/2)))*exp(-2*((Col(A)-449,88321)/41,57301)^2) + (3,21453/(27,13032*sqrt(PI/2)))*exp(-2*((Col(A)-480,25928)/27,13032)^2) + (22,18479/(40,3438*sqrt(PI/2)))*exp(-2*((Col(A)-523,784)/40,3438)^2) + (9,22338/(38,56327*sqrt(PI/2)))*exp(-2*((Col(A)-554,11411)/38,56327)^2) + (75,55035/(73,67532*sqrt(PI/2)))*exp(-2*((Col(A)-577,62044)/73,67532)^2) - for B it is: 3,23646E-4 + (2,25683/(13,84998*sqrt(PI/2)))*exp(-2*((Col(A)-417,75851)/13,84998)^2) + (50,91183/(30,102*sqrt(PI/2)))*exp(-2*((Col(A)-435,07519)/30,102)^2) + (7,929/(16,28176*sqrt(PI/2)))*exp(-2*((Col(A)-447,24219)/16,28176)^2) + (14,43253/(19,57069*sqrt(PI/2)))*exp(-2*((Col(A)-466,1769)/19,57069)^2) + (37,46447/(48,82666*sqrt(PI/2)))*exp(-2*((Col(A)-466,1769)/48,82666)^2) Now that you have the functions, the next step is to multiply your spectra (the emission intensity column) by each of the three functions, one by one. Next, you need to calculate the integrals of each of the three columns you just obtained. The value you are looking for in each case is the area under the curve. By default, Origin gives you the results of integration as a sumarry in a pop-up window, and also as a new column. The area can be either found in the summary in the pop-up, or in the "Integrated (column name)" column, as the LAST value on the bottom of the column. Now that you have the three values of area under each curve, store them in a new column (let's assume it will be column "I"). Afterwards, these values need to be divided by their sum. So another column, with values from Col(I) divided by that sum. And the values in this column are your CIE (x,y) coordinates. Interestingly enough, only the first two values matter (they are your x and y) for the CIE plot, so don't be surprised that you receive three. For the moment, I am not sure to which value the third component corresponds, but I didn't have the need to explore the subject. The step-by-step procedure mentioned above is for the CIE1931 system. I didn't use the CIE1976 standard, but I suppose that the solution is somewhat similar. Please forgive me if the explanation is too explicit for your taste, I tried to explain each and every step as simply as possible, so that everyone can use the solution and make some use of this great template without much effort. [/quote]   Check here to include your profile signature. Check here to subscribe to this topic.