Figure 2 shows the Line Profile with spread value of 20 pixels over an interference spectrum of monochromatic light (a He-Ne laser), produced by diffraction grating at a distance of 1.000 m from the screen, and the graph of the intensity versus position x along the light spectrum. The central peak and four constructive interference maxima for both sides can be easily identified, respectively at x = 0 cm, x = 2.7 cm, x = 4.0 cm and x = 5.4 cm.