Hologram element, hologram element fabricating apparatus, hologram element fabricating method, and hologram reconstructing apparatus used for reconstructing information

摘要

A reference beam (RL) is deflected by an angularly rotating mirror (25), and applied to a hologram recording medium (30) at a set incident angle. The relevant applied reference beam (RL) and a signal beam (SL) are superposed within the hologram recording medium (30), and light intensity distribution of the resultant interference fringes is recorded as a hologram. The reference beam (RL) incident on the hologram recording medium (30) is partially transmitted through the hologram recording medium (30). The relevant transmitted reference beam (RL) passes through a quarter wave plate (41) to be incident on a hologram element (40). The relevant incident reference beam (RL) has its traveling direction changed into a reverse direction by the hologram element (40) regardless of its incident angle, follows the same optical path as the incoming path, and is applied again to the hologram recording medium (30).