Graham John Woodgate

New autostereoscopic display system

This paper presents a new autostereoscopic display system based on conventional Thin Film Transistor Liquid Crystal Display technology giving bright, high quality, full color and high resolution 3D images over a wide viewing range without special glasses. In addition, 3D image look-around and multiple viewers are possible. Methods of obtaining improved image quality are described as well as interfacing with conventional video and computer image generation sources. The system is suitable for a number of professional and domestic 3D applications.

Autostereoscopic 3D display systems with observer tracking

An analysis of the basic approaches to autostereoscopic 3D display is presented, together with a discussion of the application of liquid crystal displays (LCDs) in this field. We show that of particular importance in the design of such displays is the illumination optical system and the optical quality of viewing windows produced. The window illumination quality determines many performance criteria including image fidelity, cross talk, viewing freedom and observer dynamics in a wide range of displays. The effects of degradation in window structure are described. Recent progress in 3D systems incorporating two LCD panels based on bulk and micro-optic systems is described. Further a new single LCD flat panel display is described in which observer tracking can be achieved without a requirement for moving parts. We detail the modifications to the LCD pixel structure necessary and how tracking may be achieved by manipulating the video information presented to the display panel.

Autostereoscopic display technology for mobile 3DTV applications

Mobile TV is now a commercial reality, and an opportunity exists for the first mass market 3DTV products based on cell phone platforms with switchable 2D/3D autostereoscopic displays. Compared to conventional cell phones, TV phones need to operate for extended periods of time with the display running at full brightness, so the efficiency of the 3D optical system is key. The desire for increased viewing freedom to provide greater viewing comfort can be met by increasing the number of views presented. A four view lenticular display will have a brightness five times greater than the equivalent parallax barrier display. Therefore, lenticular displays are very strong candidates for cell phone 3DTV. Selection of Polarisation Activated MicrolensTM architectures for LCD, OLED and reflective display applications is described. The technology delivers significant advantages especially for high pixel density panels and optimises device ruggedness while maintaining display brightness. A significant manufacturing breakthrough is described, enabling switchable microlenses to be fabricated using a simple coating process, which is also readily scalable to large TV panels. The 3D image performance of candidate 3DTV panels will also be compared using autostereoscopic display optical output simulations.

Key design issues for autostereoscopic 2‐D/3‐D displays

— Flat-panel 2-D/3-D autostereoscopic displays are now being commercialized in a variety of applications, each with its own particular requirements. The autostereoscopic display designer has two key considerations to address in order to meet customer needs — the optical output of the display (defined by the output window structure) and the choice of optical components. Window structure determines 3-D image resolution, achievable lateral and longitudinal viewing freedom, crosstalk, and 3-D fringe contrast. Optical-component selection determines the quality of the imaging of such windows, viewing distances, device ruggedness, thickness, and brightness. Trade-offs in window design are described, and a comparison of the leading optical component technologies is given. Selection of Polarisation Activated Microlenses™ architectures for LCD and OLED applications are described. The technology delivers significant advantages particularly for minimising nominal viewing distances in high pixel density panels and optimizing device ruggedness while maintaining display brightness.

Observer-tracking autostereoscopic 3D display systems

This paper presents an examination of the requirements for observer tracking autostereoscopic 3D display systems. The optical requirements for the imaging of autostereoscopic viewing windows in order to maintain high image quality over a large range of observer positions are described. A number of novel displays based on LCD (liquid crystal display) technology have been developed and demonstrated at Sharp Laboratories of Europe Ltd (SLE). This includes an electronically switchable illuminator for the macro-optic twin-LCD display; and a compact micro-optic twin-LCD display which maintains image quality while extending display size and viewing freedom. Work has also been in progress with flat panel displays to improve window quality using a new arrangement of LCD pixels. This has led to a new means to track such a display with no moving parts.

LP-1: Late-News Poster: High Efficiency Reconfigurable 2D/3D Autostereoscopic Display

A novel architecture to enable flat panel displays to be electrically reconfigured between a full resolution 2D mode and a half resolution, low cross talk, autostereoscopic 3D mode is described. A Polarisation Activated Microlens comprising a high precision passive birefringent lens array and a commodity switchable polariser element is added to existing LCD panels with a low cost premium. The architecture enables high optical efficiency in 2D and 3D modes and is suitable for transmissive, reflective and transflective LCD devices. The implementation of the component on a transmissive TFT-LCD is described and measured performance presented.

Efficiency analysis for multi-view spatially multiplexed autostereoscopic 2-D/3-D displays

— The wide-viewing freedom often requested by users of autostereoscopic displays can be delivered by spatial multiplexing of multiple views in which a sequence of images is directed into respective directions by a suitable autostereoscopic optical system. This gives rise to two important design considerations — the optical efficiency and the resolution efficiency of the device. Optical efficiency is particularly important in portable devices such as cell phones. A comparison is given between lens and barrier systems for various spatial multiplexing arrangements. Parallax-barrier displays suffer from reduced optical efficiency as the number of views presented increases whereas throughput efficiency is independent of the number of views for lens displays. An autostereoscopic optical system is presented for the emerging class of highly efficient polarizer-free displays. Resolution efficiency can be evaluated by investigating quantitative and subjective comparisons of resolution losses and pixel appearance in each 3-D image. Specifically, 2.2-in.-diagonal 2-D/3-D panel performance has been assessed using Nyquist boundaries, human-visual contrast-sensitivity models, and autostereoscopic-display optical output simulations. Four-view vertical Polarization-Activated Microlens technology with either QVGA mosaic or VGA striped pixel arrangements is a strong candidate for an optimum compromise between display brightness, viewing angle, and 3-D pixel appearance.

P‐183L: Late‐News Poster: A New Architecture for High Resolution Autostereoscopic 2D/3D Displays using Free‐Standing Liquid Crystal Microlenses

The trade-offs in design of high resolution (>200ppi) switchable autostereoscopic 2D/3D displays for cell phone applications are described. It is shown that as pixel density increases, LCD counter substrate thickness limits the minimum 3D viewing distance. Free-standing solid phase liquid crystal polymers enable Polarisation Activated Microlenses to deliver autostereoscopic 3D images on VGA resolution displays with 2″ diagonal. The solid lenses also improve mechanical ruggedness and facilitate reductions in system thickness. Results obtained with high precision free-standing films indicate added device thickness <1.1mm is readily achievable. The components are fabricated with known manufacturing techniques and are compatible with existing LCD and OLED displays.

The Potential Use of an Autostereoscopic 3D Display in Microsurgery

This paper investigates the potential use of a prototype micro-optic twin Liquid Crystal Display (LCD) monitor for stereomicroscopy in microsurgery. The new device displays stereoscopic images via a pair of colour Charge-Coupled Device (CCD) video cameras attached on to a surgical stereo microscope. The paper illustrates the 3D microscope-display system set-up and calibration for stereo viewing. A series of experimental techniques was devised to measure the user-response of the new display system in depth perception of a solid object against the traditional eyepieces of a stereo microscope. As a control, free viewing with the un-aided eyes was also measured. The positional data were collected using a passive mechanical arm. The results showed good correspondence between all three visualisation methods. Error analysis of our numerical findings suggests that the depth accuracy of the new device is well within the precision limits of hand movement for surgical operations. Our study also proves that there are small discrepancies within the sample population of operators using the system. A study based on the psychological and psychophysical factors influencing the system is planned.