Vibration detection apparatus, hologram apparatus, vibration detection method for the vibration detection apparatus, and recording method for the hologram apparatus

A hologram apparatus causing a coherent data beam corresponding to data to be recorded and a coherent reference beam to be applied to a hologram recording medium so as to record the data in the form of a hologram in the hologram recording medium, the hologram apparatus comprising:

• a vibration detection beam generation unit causing a vibration detection beam, incoherent to the data and reference beams and to detect the presence/absence of vibrations, to be applied to the hologram recording medium;
• a light reception/determination unit receiving the vibration detection beam emitted from the hologram recording medium after the vibration detection beam from the vibration detection beam generation unit is applied to and propagates through the hologram recording medium, the light reception/determination unit determining whether the beam receiving position is within a preset range;
• and
• an interruption unit interrupting at least one of the data and reference beams from being applied to the hologram recording medium on the basis of the determination result of the light reception/determination unit when the light reception/determination unit has determined that the position of beam reception is not within the preset range.

A vibration detection method for a medium comprising:

• causing a vibration detection beam from a vibration detection beam generation unit for detecting the presence/absence of vibrations to be applied to a medium;
• receiving the vibration detection beam emitted from the medium after the vibration detection beam from the vibration detection beam generation unit is applied to and propagates through the medium;
• determining whether the beam receiving position is within a preset range;
• and
• outputting a signal indicating that at least one of the medium and the vibration detection beam generation unit is vibrating, when the light reception/determination unit has determined that the position of beam reception is not within the preset range.

A recording method for a hologram apparatus causing a coherent data beam corresponding to data to be recorded and a coherent reference beam to be applied to a hologram recording medium so as to record the data in the form of a hologram in the hologram recording medium, the recording method comprising:

• applying a vibration detection beam, incoherent to the data and reference beams and to detect the presence/absence of vibrations, to the hologram recording medium;
• receiving the vibration detection beam emitted from the hologram recording medium after the vibration detection beam is applied to and propagates through the hologram recording medium;
• determining whether the beam receiving position is within a preset range;
• and
• interrupting at least one of the data and reference beams from being applied to the hologram recording medium on the basis of the determination result when it has been determined that the position of beam reception is not within the preset range.