2D holograms make 3D color display

Researchers from Seoul National University have developed a three-dimensional color display that uses a set of six holograms and is made from relatively compact and inexpensive components.

The three-dimensional displays could eventually be used to display any type of dynamic data for use in entertainment, art, medicine, and military applications.

The autostereoscopic system consists of red, green and blue laser diodes, a liquid-crystal spatial light modulator and a projection lens, and is 60 centimeters long. It generates slightly different images for the left and right eyes to produce the effect of natural three-dimensional vision.

Rather than three-dimensional holograms, which are difficult to calculate, the system produces two-dimensional red, green and blue holograms for each eye. These holograms are reproduced by shining a laser through a liquid-crystal display that shows the holograms' light and dark patterns.

The researchers' system shines red, green and blue lasers through a single liquid crystal light modulator, which switches rapidly among the six hologram patterns. The three color holograms for each eye overlap to produce a full-color image. The output is focused through a lens to direct the two images to the left and right eyes.

The system is relatively cheap, efficient, and color fidelity can be controlled without color filters, according to the researchers.

With a parallel processing computer system and a specialized chip, the method could be used for real-time three-dimensional broadcasting, according to the researchers.

Like most autostereoscopic displays, the researchers' system requires users to view images from a specific distance and at a particular angle.

The method to be used practically in three to five years, according to the researchers. The work appeared in the October 18, 2004 issue of Optics Express.