def fringe_spacing(wavelength, slits_distance, screen_distance):
    """
    This function provides the fringe spacing
    when the following parameters are provided.

    ===========================================

    Parameters:

    wavelength : Wavelength of light
    slits_distance : Distance between two slits
    screen_distance : Distance between slits and screen

    """
    return ((wavelength*slits_distance)/screen_distance)