In the Young's Double Slits experiment on the previous page,
the fringes produced on the screen were broad and diffuse, and hence difficult to measure
accurately. Much sharper, well-defined fringes are produced when the number of
slits, N increases. A diffraction
grating might have up to 10,000 equally spaced slits and can therefore be used
for much more accurate measurement of wavelength.
This experiment is identical to the one on the last
page, except you can now change the number of slits, N,
from between 1 and 20. Experiment with this.
Explore further...
If you'd like to explore a little further into how the fringes are produced, then click here.
