With the continued proliferation of display intensive applications for portable electronics devices, the need for lower power, higher image quality video displays has never been greater. Pixtronix is uniquely able to meet these requirements through its MEMS (micro-electo-mechanical system) display technology, which enables the development of direct view displays with breakthrough optical transmission over 60%, color gamut over 100% (of NTSC, CIE 1931), 1,000:1 contrast ratio and wide view angles.

To understand the mechanism behind the pitch change during the transient planar to the planar state transition of a cholesteric liquid crystal ͑while it is relaxing from the homeotropic state to the planar state͒, we studied a more controlled situation of pitch change in a thermochromic liquid crystal. We studied the pitch change in the liquid crystal, as a function of temperature, under various surface alignment conditions such as homogeneous and homeotropic surface alignments. In a cell with homogeneous surface treatment, the liquid crystal showed a discontinuous pitch change, while the pitch change was rather continuous in a cell with homeotropic treatment. The numerical simulations also showed an existence of continuous pitch change in a homeotropic cell, but not in a homogeneous one. This led to a prediction that when a cholesteric material is switched from the homeotropic state to the planar state, the transition may be much faster for the homeotropically treated cell as compared to the homogeneously treated cell. We performed experiments to verify this prediction with a chiral nematic mixture. Indeed, the homeotropic to planar state transition time of a homeotropic cell was 5 msec, much faster compared to about 200 msec for corresponding transition in a homogeneous cell.

Liquid crystal materials have advanced sufficiently such that very thin microdisplays can be made. A vertically aligned cell having sufficient speed for field sequential color has been designed. Simulations are shown, along with preliminary experimental results. The experimental results show a photopic contrast greater than 1000:1 at an F/# of 3.3.

The Pixtronix DMS™ (Digital Micro Shutter) display technology intrinsically provides exceptional image quality due to its optical architecture, device construction and device operation. This technology, based on MEMS micro‐shutters formed on active TFT backplanes, has enabled the development of color sequential, time division gray scale, direct‐view displays achieving breakthrough performance in wide color gamut, high brightness, high contrast ratio and wide view angles, all at roughly 1/4 the power consumption of competing TFT‐LCD or AMOLED displays of the same size and luminance. In addition, DMS™ technology also presents very good sunlight readability in transflective color modes. This readability can be attributed to reflective properties of the DMS™ optical architecture. This reflective nature enhances viewing characteristics of transmissive color modes in high ambient lighting conditions. The reflective performance is obtained without compromising transmissive mode performance as is typically the case in some of the existing display technologies. This paper will explain the performance of DMS™ display in reflective and transflective modes under high ambient lighting conditions.

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Reflective CMOS LCD light valves have high brightness and high information content. Unlike direct view displays, microdisplays also have interpixel spacing several time smaller than the cell gap. This in combination with the small pixel formats lead to fringe‐field effects having a significant impact on the effective display brightness and contrast of μLCD's.

The Pixtronix DMS™ (Digital Micro Shutter) display technology intrinsically provides exceptional image quality due to its optical architecture and device technology. This technology, based on MEMS micro‐shutters formed on active TFT backplanes, has enabled the development of color sequential, time division gray scale, direct‐view displays achieving breakthrough performance ‐ including 150% NTSC (CIE 1976 u'v' color space) color gamut, 24‐bit color, > 500:1 contrast ratio and 170° viewing angle, all at 1/4 the power consumption of comparable TFT‐LCD display modules. In addition to this, these displays present horizontal contrast viewing angle comparable to that of OLEDs providing exceptional color saturation in large angle viewing directions. This paper will briefly describe the Pixtronix DMS™ display technology. It will also describe key display architecture elements of DMS technology responsible for the excellent optical performance. The optical characterization of prototype displays and discussion of the results will be presented. A non‐emissive technology like DMS technology is able to provide performance close to that of emissive technologies like OLED at a power much lower than that of an LCD display.

The geometry and waveforms of optically compensated bend cells are optimized for field‐sequential color microdisplay applications. A unique software package based employing D. W. Berreman's modeling software as a calculation engine is used to determine the critical voltages, dynamics and optics of reflective bend cell microdisplays. The optimized configuration features an on‐off time of less than 2 ms for a 4 micron cell, and is fully compatible with existing electronics. Such a LCOS display is an excellent candidate for frame sequential color display projection applications.