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Laser Calibration (532nm) of New DVD Diffration Grating 4.7 GB

by dhaffnersr |

Resolution and Calibration for the DH 4 v4a Spectrometer

I replaced the DVD diffraction grating for my spectrometer in order to get a more balanced spectral resolution that the JDEPC-OV05 cmos camera can easily process @ its pixel specifications, also I believe with further testing, it will help, since I cannot control exposure time, only gamma correction with Spekwin32.

The new ruling density for the diffraction grating is now; 4.7 GB = 0.74mm @ 1540 lines with a wavelength range of 650nm.

My Aries 532nm Green portable laser was used to calibrate the spectral bandwidth data table is given below;


Figure.1 is the laser line at FWHM, shown on the plot with the horizontal green line at exactly 0.37323[nm]


Figure.2 is the laser peak at 531.39nm (laser allowed to warm up for 1 minute), just shy of the 531.65 central wavelength for this laser specified on it's specifications sheet.


Figure.1a is the CFL calibration I did today using Plab spectral workbench 2, you can see from the title picture, that there is clearly 2 distinct green lines and a clear second blue line, I marked all the lines just for reference purposes.


Figure.2 is a zoomed in view of the second blue spectral line


Figure.3 is a zoomed in view of the double green peaks


Figure.3a is the full plot for the CFL spectrum with a quality "fit" of 7 using the 4.7 GB DVD diffraction grating


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Correction for the data table, R = 531.39/569.8 = 0.93, NOT 1.11


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