A printer capable of producing digital 3D holograms with a high level of detail and realistic colour have been developed by researchers.
The printer will help in making high-quality objects or scenes for museum displays, architectural models, fine art or advertisements that won't need a glass or any special viewing aids.
"Our 15-year research project aimed to build a hologram printer with all the advantages of previous technologies while eliminating known drawbacks such as expensive lasers, slow printing speed, limited field of view and unsaturated colours," said research team leader Yves Gentet from Ultimate Holography in France.
"We accomplished this by creating the CHIMERA printer, which uses low-cost commercial lasers and high-speed printing to produce holograms with high-quality colour that spans a large dynamic range," added Gentet.
The study published in The Optical Society's (OSA) journal -- Applied Optics -- the researchers have described the new printer, which creates holograms with wide fields of view and full parallax on a special photographic material they designed.
Full parallax holograms reconstruct an object so that it is viewable in all directions, in this case with a field of view spanning 120 degrees.
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The printer can create holograms from 3D computer-generated models or from scans acquired with a dedicated scanner developed by the researchers. The high-quality holograms can even be used as masters to produce holographic copies.
When developing the new hologram printer, the researchers carefully studied two previously developed holographic printer technologies to understand their advantages and drawbacks.
"The companies involved in developing the first two generations of printers eventually faced technical limitations and closed," said Gentet.
"Our small, self-funded group found that it was key to develop a highly sensitive photo material with a very fine grain rather than use a commercially available rigid material like previous systems," continued Gentet.
The CHIMERA printer uses red, green and blue low-power commercially available continuous wave lasers with shutters that adjust the exposure for each laser in a matter of milliseconds.
The researchers also created a special anti-vibrating mechanical system to keep the holographic plate from moving during the recording.
Holograms are created by recording small holographic elements known as hogels, one after another using three spatial light modulators and a custom-designed full-colour optical printing head that enables the 120-degree parallax.
After printing, the holograms are developed in chemical baths and sealed for protection.
The hogel size can be toggled between 250 and 500 microns and the printing rate adjusted from 1 to 50 hertz (Hz).
For example, if a hogel size of 250 microns is used, the maximum printing speed is 50 Hz.
At this speed it would take 11 hours to print a hologram measuring 30 by 40 centimetres, about half of the time it would take using previous systems based on pulsed lasers.
The researchers used the new technology to print holograms that measured up to 60 by 80 centimetres showing various colour objects including toys, a butterfly and a museum object.
"The new system offers a much wider field of view, higher resolution and noticeably better colour rendition and dynamic range than previous systems," said Gentet.
"The full-colour holographic material we developed provides improved brightness and clarity while the low-power, continuous-wave lasers make the system easy to use," added Gentet.
The researchers said that as technology improves, especially 3D software, it may be possible to expand their hologram printing approach to medical or other advanced applications.