def calc_queensgate_constant(wavelength, free_spectra_range_bcv):
    """
    Returns the Fabry-Perot's Queensgate Constant.

    Parameters
    ----------
    wavelength (float):
    free_spectra_range_bcv (float):


    Returns
    -------
    queensgate_constant (float) :
    """
    return wavelength / free_spectra_range_bcv