Robert A. Norwood, Professor, University of Arizona College of Optical Sciences

Photorefractive Polymer 3D Display

A considerable amount of research has been dedicated to the development of three-dimensional (3D) imaging, as 2D images give only limited information about an object or a scene due to their lack of parallax and depth. 3D imaging techniques that rely on special eyewear such as polarizing goggles have unwanted side-effects such as eye fatigue and motion sickness and these systems are usually not suitable for more than one user. Holographic 3D displays are immune to these problems as they are viewable with the naked eye (autostereoscopic) by multiple users, and simulate natural human vision. Holograms simultaneously satisfy most human depth cues such as occlusion, parallax and depth of field. Current commercially available holographic displays are capable of displaying terabytes of data, and come at practically any size with full-colour and very high resolution, presenting extremely realistic 3D images.

Holographic 3D display

One of the major shortcomings of commercially available holographic 3D displays is the static nature of the 3D images. These holographic displays employ photopolymers that lack image-updating capability, resulting in their restricted use and high cost. For military applications (i.e. visualization of the battle space for mission planning and command-and-control) image-updating capability is a very important requirement as the battle space is a dynamic environment where the positions of the troops and military vehicles continuously change. Being able to visualize such changes in 3D is a significant advantage that would assist in mission planning, minimize causalities and reduce collateral damage. There are several technologies that allow real-time (dynamic) display of 3D images, unfortunately, however, these displays are limited to small sizes and resolutions that prevent their practical use.

Recently we demonstrated a single color updateable 3D display using photorefractive polymers capable of recording and displaying new images every few minutes. The display employed newly formulated photorefractive polymers with close to 100% diffraction efficiency using writing beams at 532 nm (green) and reading at 633 nm (red).

We have fabricated the world's largest area (4 x 4 inch2) photorefractive devices from this polymer composite and have now fabricated films covering 8 x 10 inch2. We have invented a new technique to improve the writing time that is based on the manipulation of the applied voltage in photorefractive polymers, which allowed us to demonstrate faster recording of holograms (about a second per hogel) with a diffraction efficiency of 55% and storage time of 3 hours. The thin-film devices made of this polymer exhibit excellent electrical and optical stability and long life-time.

As shown below, we have recently progressed to making color holograms:

Color hologram

References

  • P.-A. Blanche, S. Tay, R. Voorakaranam, P. St.-Hilaire, C. Christenson, T.Gu, W. Lin, D. Flores, P. Wang, M. Yamamoto, J. Thomas, R. A. Norwood, and N. Peyghambarian, "An updatable holographic display for 3D visualization," J. Display Tech. 4, 424 (2008).
  • S. Tay, P. A. Blanche, R. Voorakaranam, A. V. Tunc, W. Lin, S. Rokutanda, T. Gu, D. Flores, P. Wang, P. St. Hilaire, G. Li, J. Thomas, R. A. Norwood, M. Yamamoto and N. Peyghambarian, "An updateable 3D holographic display, " Nature 451, 694 (2008).
  • S. Tay, J. Thomas, B. Momeni, M. Askari, A. Adibi, P. J. Hotchkiss, S. R. Marder, R. A. Norwood, and N. Peyghambarian, "Planar photonic crystals infiltrated with nanoparticle/polymer composites," Applied Physics Letters 91, 221109 (2007).
  • M. Eralp, J. Thomas, S. Tay, P. A. Blanche, A. Schülzgen, R. A. Norwood, M. Yamamoto, and N. Peyghambarian, "Variation of Bragg condition in low glass-transition photorefractive polymers when recorded in reflection geometry," Optics Express 15, 11622 (2007).
  • M. Eralp, J. Thomas, S. Tay, G. Li, A. Schülzgen, R. A. Norwood, M. Yamamoto, and N. Peyghambarian, "Submillisecond response of a photorefractive polymer under single nanosecond pulse exposure," Applied Physics Letters 89, 114105 (2006).
  • M. Eralp, J. Thomas, G. Li, S. Tay, A. Schülzgen, R. A. Norwood, N. Peyghambarian, and M. Yamamoto, "Photorefractive polymer device with video-rate response time operating at low voltages," Optics Letters 31, 1408 (2006).
  • S. Tay, J. Thomas, M. Eralp, G. Li, J. Winiarcz, M. Yamamoto, S. Barlow, G. A. Walker, S. R. Marder, R. A. Norwood, A. Schülzgen and N. Peyghambarian, "High performance photorefractive polymer operating at 1550nm with near-video-rate response time," Applied Physics Letters 87, 171105 (2005).
  • G. Li, M. Eralp, J. Thomas, S. Tay, A. Schülzgen, R. A. Norwood, and N. Peyghambarian, "All-optical dynamic correction of distorted communication signals using a photorefractive polymeric hologram," Applied Physics Letters 86, 161103 (2005).