A novel stereoscopic/3D desktop monitor has been developed that combines the output of two active matrix LCDs (AMLCDs) into a stereo image through use of a unique beamsplitter design. This approach, called the StereoMirror, creates a stereo/3D monitor that retains the full resolution, response time and chromaticity of the component displays. The resultant flicker-free image, when viewed with passive polarizing glasses, provides an unprecedented level of viewing comfort in stereo. The monitor also is bright enough to use in normal office lighting. The display has excellent optical isolation of the two stereo channels and a wide viewing angle suitable for multi-viewer use. This paper describes the architecture of the system and the principal of conservation of polarization that results in the full-definition stereo image. Optical performance results are also described. Practical considerations will be discussed, including system interface requirements, conversion between stereo/3D and monoscopic viewing and comparison to other stereo display approaches. The higher level of performance provided by the StereoMirror allows for stereo viewing to be viable in new imaging markets as well as permitting a more effective use of stereo in existing markets. These applications are discussed.
The paper presents methodologies for characterizing liquid crystal displays (LCDs) and the image quality of two new high-performance monochrome LCDs, a 2- and a 5-million-pixel display. The systems' image quality is described by on-axis characteristic curves, luminance range and contrast, luminance and contrast as a function of viewing angle, diffuse and specular reflection coefficients, color coordinates, luminance uniformity across the display screen, temporal response time and temporal modulation transfer function (MTF), spatial MTF, spatial noise power spectra and signal-to-noise ratios.
The LCDs are equipped with an internal photosensor that maintains a desired maximum luminance and calibration to a given display function. The systems offer aperture and temporal modulation to place luminance levels with more than 12-bit precision on a desired display function and achieve very uniform contrast distribution over the luminance range. The LCDs have image quality that is superior in many respects to high-performance and high-resolution cathode-ray-tube (CRT) displays, except for the temporal MTF and the spatial noise. Spatial noise appears to be comparable to CRT display systems with P4 or P104 phosphor screens.
AMLCDs have an inherent problem with accumulation of DC charge as a result of manufacturing variation, AMLCD drive waveforms, and temperature variation. The accumulation of DC charge in an AMLCD results in image sticking or image retention. This paper addresses the root cause of DC charge accumulation, design and manufacturing factors in reducing DC charge, and measurement metrics for determining degree of image retention.
Liquid crystal (LC) material properties change with temperature. The goal is to find a material that will have a very wide temperature range (minus 54 degrees to plus 102 degrees Celsius) and maintain good response time and viewing angle performance. We find that LC materials with a high clearing point (greater than +100 degrees Celsius) have too high of a viscosity (approximately 26 mm2/s) at room temperature to meet the response time criteria (less than 25 msec.) if avionics display. Several new LC materials were studied, and critical parametric for avionics are discussed.
The organic black matrix material, formulated by a photosensitive acrylic resin and color pigments, has superb optical performance with a specular reflection of 0.36% at 30 degree(s) incident angle. Its optical density, with help from a metallic layer, has been achieved at 5.5. Since this organic material is a negative photoresist, the fabrication process is rather simple. Using such a black matrix, a high- resolution 2.4' X 2.4' full-color (alpha) -Si TFT LCD with 480 X 480 dots has been successfully fabricated. In combination of a wide-view retardation film, this AMLCD unit is suitable for high-performance display applications.
Viewing angle improvement with compensation films for LCD is reviewed with special emphasis on the TN AMLCD. Different types of compensation films are introduced together with the methods for their characterizations. Principles behind film compensation designs for different LCD modes are reviewed and design trade-offs discussed.
Liquid crystal displays have limitations of viewing angles. A loss of contrast and gray level inversion occur at wide angles. Use of retardation films drastically improves viewing envelops to have contrast ratios of greater than 10:1 at +/- 60 degrees horizontal and -5 degrees to +35 vertical. Data measured on few OIS wide viewing angles displays will be presented. Gray level separation and other related viewing angle issues will be discussed.
Polarizers have sensitivity to temperature and humidity combination. They are also sensitive to high doses of UV exposure. To guarantee a long life of a liquid crystal display the polarizers have either to be of special quality, or there should be special means to protect them. A study related to the long term stability have been conducted on several types of high efficiency iodine based polarizers. The test results and recommendations will be presented in this paper.
A high-resolution, wide-angle view normally black active matrix liquid crystal display (AMLCD) has been developed for the National Aeronautics and Space Administration- Rockwell Space Shuttle glass cockpit upgrade. With nine 6.71 by 6.71 in. active area AMLCDs on the front panel, all containing vehicle flight information, the displays must exhibit optimal performance over the entire AMLCD viewing envelope [+/- 60 deg horizontal (H) and -10/+45 deg vertical (V)], under dark and high ambient flight deck lighting conditions. Cross-cockpit AMLCDs must support higher off-axis contrast ratios, vertical and horizontal gray-level stability, a consistent and predictable mixture of primary colors, saturated colors over wider angles, and a darker background with respect to typical AMLCD applications. Manufacturing AMLCDs with these characteristics requires special designs for the AMLCD, diffuser, backlight, and liquid crystal display drive scheme, and special manufacturing processes and techniques. This paper addresses Space Shuttle wide- angle normally black AMLCD requirements, optical performance, and manufacturing considerations.
We present a new method of tiling flat panel displays to a continuous large display. The method was tested for color Active Matrix Liquid Crystal Display (AMLCD) with backlight. Diverging glass fiber-optic faceplates configuration were used to show the principle however the method is applicable and was verified also with plastic faceplates and micro-channels (hollow pipes). The manufacturing of the displays and the faceplates are done separately and then assembled together. The method presented shows very little loss of resolution and very wide viewing angles. There are no limitations to the number of tiled displays in both horizontal and vertical directions.