his first presentation to the commission, recommending what he called lentilles à échelons ('lenses by steps') to replace the reflectors then in use,...

dans le domaine x-uv a l'aide de lentilles a zones de fresnel (Thesis). Paris 6. "Laboratoire de Métrologie Optique | Centre de rayonnement synchrotron...

his first presentation to the commission, recommending what he called lentilles à échelons (lenses by steps) to replace the reflectors then in use, which...