Patent ID: 6999397

Claim:
A holographic digital data storage system compatible with a CD or DVD player, the system comprising: a light source for generating a reference beam; a holographic optical element for generating, if the reference beam is irradiated, a reproduced beam corresponding to one of a plurality of beams of specific sizes, wherein interference patterns between the reference beam and the plurality of beams of specific sizes are recorded in the holographic optical element, and wherein the reproduced beam is one of a holographic reproduced beam, a CD reproduced beam and a DVD reproduced beam; means for splitting each reproduced beam into a reflected beam and a transmitted beam, wherein, if the holographic reproduced beam is generated from the holographic optical element, one of the reflected beam and the transmitted beam is defined as a holographic reference beam; means for modulating the other of the reflected beam and the transmitted beam with an input signal to generate a holographic signal beam corresponding to the input signal; means for, if only the holographic reference beam is irradiated onto a holographic digital data storage medium, displaying a holographic image reproduced from the holographic digital data storage medium and, if the CD or DVD reproduced beam is irradiated onto a CD or DVD medium, detecting a beam reflected from the CD or DVD medium.