Production method and device for hologram

A method for producing a hologram using a two-beam laser interference exposure process, said method comprising the steps of:

• using as a light source a femtosecond laser having a pulse width of 900-10 femtoseconds and a peak output of 1 GW or more, and capable of generating a pulse beam at or close to the Fourier transform limit;
• dividing the pulse beam from said laser into two by a beam splitter;
• controlling said two beams temporally through an optical delay circuit and spatially using plane and concave mirrors each having a finely rotatable reflection surface;
• and
• converging said two beams on a surface of or within a substrate for recording a hologram at an energy density of 100 GW/cm2 or more with keeping each polarization plane of said two beams in parallel so as to match the converged spot of said two beams temporally and spatially,
• wherein a hologram is recorded irreversibly on said substrate formed of a transparent material, semiconductor material or metallic material, based on a relief in the configuration of the surface of said substrate and/or a variation in the refractive index of said substrate in connection with an abrasion of said substrate or a structural change in the atomic arrangement of said substrate caused by the high-density energy irradiation.