We propose a multilayer-coated mirror for the first mirror of a beamli
ne. Calculated reflectivities of over 80% for B4C/W and C/Ni constant
d-spacing multilayer-coated mirrors are obtained at 6 keV. Moreover, b
y using the constant d-spacing multilayer-coated mirror, a monochromat
ic light source with high reflectivity and high resolution is obtained
at the glancing angle of 1.5 degrees. Furthermore, it is determined t
hat a graded d-spacing multilayer-coated mirror, i.e., a supermirror,
is effective in this photon energy region since the half-width at half
-maximum of the reflectivity increases. A multilayer-coated reflection
mirror for beamline optics is promising for applications in microfabr
ication and structure analysis of materials.