Full‐parallax autostereoscopic display with scalable lateral resolution using overlaid multiple projection

Abstract— A method to increase the viewing resolution of an autostereoscopic display without increasing the density of microlenses is proposed. Multiple projectors are used for the projection images to be focused and overlaid on a common plane in the air behind the microlens array. The multiple overlaid projection images yield multiple light spots inside the region of each elemental lenslet of the microlens array. This feature provides scalable high‐resolution images by increasing the number of projectors. Based on the proposed method, a prototype display that includes 15 projectors was designed and built. 3‐D images were successfully reproduced on the prototype display with full parallax and a wide viewing angle of 70°.     

Fast‐response study of polymer‐stabilized VA‐LCD

Abstract— Polymer stabilization is introduced in VA‐type LCDs, and fast response time can be achieved along with a high contrast ratio.¹ A small amount of reactive monomer is mixed with liquid crystal and forms a polymer layer above the alignment layer by using a UV process. The pre‐tilt angle of the liquid crystal is stabilized, and a faster response time can be realized when the bias pre‐tilt angle from 90° is increased. The properties of reactive monomers and liquid crystal and the conditions of the UV process were studied. Based on the application of the proper monomer and LC, and an optima UV process, a 65‐in. 240‐Hz full‐HD TFT‐LCD, with a faster response time and high contrast ratio, has been developed.     

Analog LCOS SLM devices for AR display applications

Liquid crystal on silicon (LCOS) device is a potential candidate for spatial light modulators (SLMs) due to its high resolution and the wide range of tunable phase retardation. Besides the telecom applications, SLM is also very promising for display applications, especially for the augmented reality (AR) displays. In this paper, we will discuss the advantages of analog LCOS SLM compared with the digital one. A 0.6‐in short‐loop sample test result with precise cell gap controlled is discussed. A fast liquid crystal with high birefringence that attains less than 2.5‐ms full‐on–full‐off response time is also introduced. Regarding the computer‐generated hologram (CGH), a new algorithm called multiconstraints angular spectrum algorithm (MASA) is proposed to enhance the image quality of dual‐plane holographic projection.     

Implementation of polarization‐multiplexed tiled projection integral imaging system

Abstract— A 40‐in. tiled projection integral imaging system has been implemented, adopting a polarization‐multiplexing technique. The system is composed of two full‐high‐definition (HD) projectors, a time‐varying polarizer, a polarization preserving screen, polarization films, a lens array, and a control unit. An elemental image set is projected using two full‐HD projectors to enhance the resolution of the system. The viewing region of the system is increased by using a polarization switching method. The polarization state of the elemental image set is changed by the time‐varying polarizer, and the elemental image set is diffused by the polarization preserving screen. The elemental image set with a preserved polarization state forms a three‐dimensional image with increased viewing angle by the integration of a lens array with polarization films. A 60‐in. tiled projection integral imaging system was also demonstrated using four full‐HD projectors.     

Optical simulation for cross‐talk evaluation and improvement of autostereoscopic 3‐D displays with a projector array

Abstract— Multi‐view spatial‐multiplexed autostereoscopic 3‐D displays normally use a 2‐D image source and divide the pixels to generate perspective images. Due to the reduction in the resolution of each perspective image for a large view number, a super‐high‐resolution 2‐D image source is required to achieve 3‐D image quality close to the standard of natural vision. This paper proposes an approach by tiling multiple projection images with a low magnification ratio from a microdisplay to resolve the resolution issue. Placing a lenticular array in front of the tiled projection image can lead to an autostereoscopic display. Image distortion and cross‐talk issues resulting from the projection lens and pixel structure of the microdisplay have been addressed with proper selection of the active pixel and adequate pixel grouping and masking. Optical simulation has shown that a 37‐in. 12‐view autostereoscopic display with a full‐HD (1920 × 1080) resolution can be achieved with the proposed 3‐D architecture.     

OLED‐based pico‐projection system

Abstract— Two pico‐projection systems, a monochrome green and a full‐color system, based on high‐efficiency OLED microdisplays (VGA; pixel size, 12 μm) are presented. Both optical systems are described by a numerical aperture of about 0.3, a magnification of 15x, and a working distance of 300–360 mm. The frequency limit of both systems is 42 cycles/mm at an image contrast of about 60%. The monochrome projection system with a volume smaller than 10 cm³ consists of one green OLED and a projection lens with five elements. The measured luminance in the image plane is about 0.061 lm. The image has a diagonal of 150 mm with a working distance of about 300 mm and has a considerable image contrast of 396:1. The second system combines three high‐brightness OLEDs, red, green, and blue colored, together with a projection lens and an image‐combining element, and an X‐Cube to achieve full‐color projection. The estimated luminance value for the three‐panel projection unit with an OLED luminance of 10,000 cd/m² for each display will be about Φcalculated = 0.147 lm. In this paper, the system concepts, the optical designs, and the realized prototypes of the monochrome and full‐color projection system are presented.     

Video processing for active‐matrix polymer OLED TV

Abstract— Active‐matrix OLED panels have inherent features that allow a higher‐quality image reproduction than LCD panels, i.e., high‐contrast, fast response time, and the capability to produce locally high peak luminance levels. We demonstrated a 13‐in.‐ink‐jet‐printed active‐matrix polymer‐OLED prototype for TV applications at SID 2004. This prototype is used as a carrier for studying video‐processing algorithms that take full advantage of the specific characteristics of OLEDs. Addressing schemes, gamut conversion, histogram‐based brightness control, and sparkle processing will be discussed.     

Design of a compact projection display for the visualization of 3‐D images using polarization sensitive eyeglasses

Abstract— A compact optical architecture of a three‐dimensional projection display that simultaneously generates two full‐color images with an orthogonal polarization state is presented. The minimal size of the optical engine was investigated and a compact illumination system using light‐emitting diodes as light sources was designed. The effect of dichroic mirrors in the illumination path on the stereoscopic images was also investigted.     

Projection optical system for a compact rear projector

Abstract— A new projection optical system with an exceptionally wide field angle of 160° and a short projection distance of 125 mm for a 62‐in. screen has been developed. It is constructed based on the Direct Projection Method which does not require a back mirror. This paper presents a new optical design concept and the characteristics of a prototype optical system.     

An introduction to PSS‐LCDs: A fast‐optical‐response smectic LCD

Abstract— A new type of fast‐optical‐response liquid‐crystal display is introduced. This display uses a certain type of smectic liquid‐crystal material that has a fast optical response as well as a native wide viewing angle. Unlike well‐known smectic‐based LCD technologies, this new type of LCD technology is highly compatibile with most nematic‐based LCDs. This compatibility provides advantages for practical uses. Here, the initial molecular alignment and drive concept as well as the general performance of this new display technology are discussed.     

Optical response of helix‐free FLC: Continuous gray scale,fastest response,and lowest control voltage

Electro‐optical response of a display cells with novel helix‐free FLC (differently, compensated helix ferroelectric—CHF) is considered. Predominance of the shear viscosity in the soliton mode of FLC director reorientation leads to weakening the temperature dependence of the response time. Increasing the electric field frequency expands this temperature interval, and it is 15°C… 45°C for the frequency about 3 kHz at ±1.5 V in a display cell with FLC viscosity of 0.7 P. Increasing the rotational viscosity up to 1.0 P provides the increase of speed ability due to Maxwell's nature of energy dissipation. The optical response time of 24 µs and light modulation frequency of 7 kHz were achieved at the amplitude of control voltage pulses ±1.5 V. Thus, like NLC based cells, the experimental samples of CHF based display cells at the same (or even lower) value of voltage and electric field tension (1–2 V/µm) show the continuous gray scale and hysteresis‐free modulation characteristic (up to 5 kHz) but can provide 40–50 times (!) higher speed. These break‐through results characterize CHF as the most high‐speed materials for future 3D displays and displays using field sequential color technique, including FLCoS and TFT addressed, as well as displays with new functional properties.     

Development of 100‐in. TFT‐LCDs for HDTV and public‐information‐display applications

Abstract— LCDs have achieved a full‐high‐definition resolution of 1920 × 1080 (16:9), 600‐nit brightness, 3000:1 dynamic contrast ratio, 92% color gamut, 178° viewing angle, and 5‐msec response time at all gray levels and are targeted for HDTV and public‐information‐display applications. Some unique technologies, such as Cu bus line, advanced wide view polarizer, and wide‐color‐gamut lamp, were applied. A new stitching‐free technology was developed to overcome the size limitation of the photomask in both the TFT and color‐filter processes. The size of the panel (100 in.), based on the wide format (16:9), is determined by the maximum efficiency of the world's first seventh‐generation line (glass size, 1950 × 2250 mm) in LG.Philips LCD's (LPL) Paju display cluster. The issues facing 100‐in. TFT‐LCDs will be discussed.     

A video‐speed reflective display based on electrowetting: principle and properties

Abstract— Electrowetting is presented as a novel principle for a reflective display. By contracting a colored oil film electrically, an optical switch is obtained with many attractive properties that make it very suitable for use as a reflective display, for instance, as electronic paper. Firstly, it has the high reflectivity (>40%) and contrast ratio (15) required for a paper‐like optical appearance. In addition, the principle shows a video‐rate response time (<10 msec) and has a clear route toward a high‐brightness color display. Finally, the electro‐optical response is independent of cell‐gap thickness, which will be very beneficial when moving toward a flexible display.     

Fast‐response liquid‐crystal displays using crossed fringe fields

Abstract— A fast‐response and wide‐view liquid‐crystal display (LCD) using the crossed fringe‐field‐switching (CFFS) mode is proposed, where the fringe‐field electrodes exist on both the top and bottom substrates. The bottom fringe field is used to turn on the LC directors and the top fringe field is used to assist in the LC decay process. The decay time is reduced by ～2× compared to that of the conventional FFS mode between the full bright and dark states, and more than a 2× improvement is obtained for other gray‐scale transitions. This CFFS mode also preserves the wide‐view characteristics as the conventional FFS mode. Its applications to LCD TVs and monitors for reducing image blur are addressed.     

Novel 120‐Hz TFT‐LCD motion‐blur‐reduction technology with integrated motion‐compensated frame‐interpolation timing controller

Abstract— Samsung has developed a high‐resolution full‐HD (1920 × 1080) 120‐Hz LCD‐TV panel using a novel pixel structure and a motion‐compensated frame‐interpolation (McFi) single‐chip solution. Our latest work includes launch of a 70‐in. full‐HD panel, the world's largest LCD TV in mass production, with a 120‐Hz frame rate. A serious problem involving the charging time margin has been completely overcome through the use of a new alternative 1G‐2D pixel structure and a new driving scheme. Compared with conventional dot‐inversion driving, our new dot‐inversion method, which is a spatial averaging technique, can save power because the column drivers are operated using vertical inversion driving. In addition, McFi, which merges individual ME/MC and timing‐controller (TCON) ICs and memories, has been developed and applied in a mass‐production product for the first time ever. The McFi solution provides 120‐Hz driving with the lowest possible system cost. Motion‐picture response time (MPRT) has been reduced from 1 5 to 8 msec. Moreover, for the case of 24‐Hz film source mode, motion judder has been completely eliminated. As a result, a lineup consisting of 40‐, 46‐, 52‐, 70‐, and 82‐in. LCD‐TV panels with high quality and manufacturability has been made possible.     

Electro‐optical parameters of FLC layers stabilized by a typical polymer net

Abstract— A typical polymer net with microcells of different sizes (from 25 × 25 to 200 × 200 μm) was formed by using a lithographic process, both on glass and flexible polymeric substrates. To investigate the influence of polymeric walls on FLC‐display cell operation, the typical electro‐optical parameters of FLC layers — light transmission and scattering, optical contrast ratio and response time — were measured under different conditions, such as display cell preparation and processing, driving voltage, microcell dimensions, and temperature.     

High‐quality direct‐view display combining multiple integral 3D images

This paper proposes a method for combining multiple integral three‐dimensional (3D) images using direct‐view displays to obtain high‐quality results. A multi‐image combining optical system (MICOS) is used to enlarge and combine multiple integral 3D images without gaps. An optical design with a simple lens configuration that does not require a diffuser plate prevents the deterioration in resolution resulting from lens arrangement errors and the diffuser plate. An experiment was performed to compare a previously developed method with the proposed method, and the latter showed a significant improvement in image quality. A method for expanding the effective viewing angle of the proposed optical design was also developed, and its effectiveness was confirmed experimentally. A prototype device of the proposed optical design was constructed using a high‐density organic light‐emitting diode (OLED) panel with 8K resolution and 1058 ppi pixel density to achieve 311 (H) × 175 (V) elemental images, a viewing angle of 20.6° in both the horizontal and vertical directions, and a display size of 9.1 in. In addition, the proposed optical design enabled making device considerably thinner, ie, with a thickness of only 47 mm.     

Feasibility study of novel fast‐switching liquid crystal displays using electric birefringence effect

Both theoretical and experimental studies were made on electric birefringence effect of nematic liquid crystals in isotropic phase with respect to its applicability to novel LCDs. It was confirmed that response times are <1 ms, and a critical point exists where electro‐optic hysteresis vanishes. Substrate surface treatments were also found to improve the electro‐optic characteristics. The results are promising for both projection and direct view display applications featuring fast switching and high image quality.     

Multioutputs single‐stage gate driver on array with wide temperature operable thin‐film‐transistor liquid‐crystal display for high resolution application

A hydrogenated amorphous silicon (a‐Si:H) thin‐film transistor (TFT) gate driver with multioutputs (eight outputs per stage) for high reliability, 10.7‐inch automotive display has been proposed. The driver circuit is composed of one SR controller, eight driving TFTs (one stage to eight outputs) with bridging TFTs. The SR controller, which starts up the driving TFTs, could also prevent the noise of gate line for nonworking period. The bridging TFT, using width decreasing which connects between the SR controller and the driving TFT, could produce the floating state which is beneficial to couple the gate voltage, improves the driving ability of output, and reaches consistent rising time in high temperature and low temperature environment. Moreover, 8‐phase clocks with 75% overlapping and dual‐side driving scheme are also used in the circuit design to ensure enough charging time and reduce the loading of each gate line. According to lifetime test results, the proposed gate driver of 720 stages pass the extreme temperature range test (90°C and ?40°C) for simulation, and operates stably over 800 hours at 90°C for measurement. Besides, this design is successfully demonstrated in a 10.7‐inch full HD (1080 × RGB×1920) TFT‐liquid‐crystal display (LCD) panel.     

Advanced level‐adaptive overdrive (ALAO) method applicable to full‐HD LC TVs

Abstract— In this paper, we report on the development of an advanced level‐adaptive overdrive (ALAO) method applicable to full‐HD LC TVs, which makes it possible not only to reduce the gray‐level response time to less than one fourth, but also to improve the S/N ratio for still images by 10 dB; and further to reduce the circuit cost for the LAO method to almost half that of the prior LAO circuit. We have applied the ALAO method to a full‐HD LC front projector with 1.84 Mpixels and a screen size larger than 100 in., and we obtained high‐quality full‐HD moving images.