[en] The effect of intense pulses of laser-produced x rays upon the reflective and diffractive properties of metal mirrors and multilayered mirrors (artificial crystals) have been investigated. Laser pulses from a Nd-glass pulsed laser system of 25 ns pulse width and 50 J energy were focused onto a copper target to generate the required x-ray pulses. A polished planar sample of nickel was used to reflect the 1.0 to 1.3-keV x rays onto photographic film. The x-ray flux onto the mirror (at grazing incidence angles near 3.5⁰) was split into two adjacent fields with a beryllium filter over one field and with an equal thickness beryllium filter placed over the film holder covering the adjacent field. Thin pieces of Kimfol were used as debris shields ahead of the mirror sample. This technique provided an in-situ normalization since both a low intensity and a high intensity irradiation can be simultaneously achieved on adjacent portions of the sample. A similar technique was used to study reflection by a multilayer sample of carbon-tungsten carbide layering and 19.6A⁰ spacing. Experimental details and the results obtained are presented