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Abstract— Holographically reflective LCDs are approaching the production phase in Motorola portable products. They add improved performance and product differentiation to TN, STN and FSTN LCDs. Key features include up to two to three times improvement in brightness and contrast and elimination of image degradation due to glare. Without consuming additional power, the hologram provides a “backlit” appearance which further differentiates the product. Moreover, the current version of the holographic reflector has been “tuned” to the LCD so that the effective viewing cone is retained or even expanded slightly.

Experimentally determined maximum electroabsorption in GaAs/Al0.33Ga0.67As multiple quantum wells over the quantum well width range of 17–260 Å is related to the confinement of the electronic wave functions in the quantum well, increasing with enhanced confinement. However, for very narrow wells, this increase in maximum electroabsorption is diminished by strong broadening of the excitonic resonances due to phonon scattering, eventually leading to a peak value of 22 200 cm−1 at a 35 Å well width.

Transmission holographic film for brightness enhancement in full color reflective LCDs is proposed. The hologram is attached to the front of the LCD. The goal is paper-like brightness within the viewing zone under typical ambient lighting conditions. Optimum viewing and illumination angles have been identified. Modeling and measurements on holograms show that a viewing zone of 20° × 40° will provide a 12X film gain which is adequate to maintain a wide color gamut and brightness.