Calibrating the wavelength of the spectrometer, Appendix a – Ocean Optics HR2000CG-UV-NIR User Manual
Page 36
 
Appendix A
Calibrating the Wavelength of the Spectrometer
Perform the steps below to calibrate the wavelength of the spectrometer:
1. Place OOIBase32 into Scope Mode and take a spectrum of your light source. Adjust the integration time
(or the A/D conversion frequency) until there are several peaks on the screen that are not off-scale.
2. Move the cursor to one of the peaks and position the cursor so that it is at the point of maximum intensity.
3. Record the pixel number that is displayed in the status bar or legend (located beneath the graph). Repeat
this step for all of the peaks in your spectrum.
4. Use the spreadsheet program or calculator to create a table like the one shown below. In the first column,
place the exact or true wavelength of the spectral lines that you used.
In the second column of this worksheet, place the observed pixel number. In the third column, calculate 
the pixel number squared, and in the fourth column, calculate the pixel number cubed. 
True Wavelength (nm)
Pixel #
Pixel #
2
Pixel
#
3
Predicted
Wavelength
Difference
253.65 
296.73 
302.15 
313.16 
334.15 
365.02 
404.66 
407.78 
435.84 
546.07 
576.96 
579.07 
696.54 
706.72 
727.29 
738.40 
751.47 
175 
296 
312 
342 
402 
490 
604 
613 
694 
1022 
1116 
1122 
1491 
1523 
1590 
1627 
1669 
30625 
87616 
97344 
116964 
161604 
240100 
364816 
375769 
481636 
1044484 
1245456 
1258884 
2223081 
2319529 
2528100 
2647129 
2785561 
5359375
25934336 
30371328 
40001688 
64964808 
117649000 
220348864 
230346397 
334255384 
1067462648 
1389928896 
1412467848 
3314613771 
3532642667 
4019679000 
4306878883 
4649101309 
253.56 
296.72 
302.40 
313.02 
334.19 
365.05 
404.67 
407.78 
435.65 
546.13 
577.05 
579.01 
696.70 
706.62 
727.24 
738.53 
751.27 
0.09 
0.01 
-0.25
0.13
-0.05 
-0.04 
-0.01 
0.00 
0.19 
-0.06 
-0.09 
0.06
-0.15
0.10 
0.06 
-0.13
0.19
(Continued)
HR2000 High-Resolution Fiber Optic Spectrometer
32
Independent
Variable
Dependent
Variables
Values Computed
from the Regression
Output