How is acoustical holography different from optical holography?

The primary difference between acoustical holography and optical holography lies in the type of waves used to create the image. While optical holography utilizes light waves—typically from a laser—to record and reconstruct three-dimensional images, acoustical holography employs sound waves to achieve a similar result.12

In optical holography, the process involves recording both the amplitude and phase content of reflected light waves to reconstruct a three-dimensional character. Acoustical holography functions on a comparable principle, creating an "acoustic hologram" that serves as a three-dimensional representation of an object using sound.21

Because sound waves have different physical properties than light—such as their tendency to diffract more readily around everyday objects due to their longer wavelengths—the practical application and behavior of these waves differ from the light beams used in standard optical systems.3