A microretarder for stereoscopic display is a film consisting of horizontal or vertical stripes with alternating null
and half-wave phase retardation states. An LCD with a microretarder attached on the front side can display good-quality
stereoscopic images when viewed with polarization glasses. It is now the easiest and cheapest way to present
stereoscopic images on a flat-panel display. However, the space caused by the glass between the retarder layer and the
LC layer of the panel seriously limits the vertical view angle, which, in turn, limits the application of this technology. In
this paper, a process for thin-film microretarder is developed using reactive liquid crystal. The material and the process
are essentially compatible with current LC panel processes. Since the thin-film microretarder is to be fabricated in the
cell of an LC panel, the retarder layer and the LC layer can be fabricated as close to each other as possible. A nearly
unlimited 3D view angle can be achieved for the display.
The properties of periodicity and linear separation/combination of optical retardation are adopted to develop the Random-Retardation-Encoding anti-counterfeiting technology. In the experiments of this paper, the authentication pattern was divided into two parts with different random retardation distribution. The two parts of random retardation pattern were fabricated on two separate films. One of them can be used as the authentication tag, and the other is used for the identification of the authentication tag. Because the resolution of the random retardation pattern can be made very high, it's very hard to counterfeit the authentication tag without knowing the original design pattern. In addition, the transparency property of the retardation film makes it easy to be integrated with other anti-counterfeiting method, e.g. it can be laminated on a hologram without destroying the visual performance of the hologram while the authentication function of the retardation film is still maintained.
Entertainment is usually considered an important application for stereoscopic display technologies. In order to provide more realistic and exciting VR effect, it is desirable to have as large screen as possible. However, the screen sizes of current autostereoscopic display technologies are limited by either the displaying panel or the optical components. In a government-sponsored project, we designed and fabricated a novel projection screen for autostereoscopic display. The screen consists of two layers of microretarder and a layer of polarization reserved diffuser. Both the screens and the projectors can be arrayed to build a large autostereoscopic display system. Curved or multi-plane screens are also possible. This kind of autostereoscopic display screen has the advantages of ease to scale up, low cost and no precise alignment between the projectors and the screen required. In this paper, the manufacture considerations of such a screen are studied and the experimental results are presented.