Stereoscopic images are hard to get right, and comfortable images are often only produced after repeated trial and error. The main difficulty is controlling the stereoscopic camera parameters so that the viewer does not experience eye strain or double images from excessive perceived depth. Additionally, for head tracked displays, the perceived objects can distort as the viewer moves to look around the displayed scene. We describe a novel method for calculating stereoscopic camera parameters with the following contributions: (1) Provides the user intuitive controls related to easily measured physical values. (2) For head tracked displays; necessarily ensures that there is no depth distortion as the viewer moves. (3) Clearly separates the image capture camera/scene space from the image viewing viewer/display space. (4) Provides a transformation between these two spaces allowing precise control of the mapping of scene depth to perceived display depth. The new method is implemented as an API extension for use with OpenGL, a plug-in for 3D Studio Max and a control system for a stereoscopic digital camera. The result is stereoscopic images generated correctly at the first attempt, with precisely controlled perceived depth. A new analysis of the distortions introduced by different camera parameters was undertaken.
One recently reported approach to flat panel autostereoscopic 3D displays under investigation at Sharp Laboratories of Europe Ltd. (SLE) uses a high precision patterned optical half wave retarder combined with a re-configurable output polarizer to 'develop' a parallax barrier structure attached to an LCD display panel. Such a barrier is invisible without the polarizer and thus a 2D/3D configurable display can be formed. A discussion of cross talk and white level variation in the 3D mode will be made with reference to Fresnel diffraction in the display. A model will be presented and justified in the light of the panel geometry. This model will be compared with measured cross talk, window structure and white level variation in such a 2D/3D configurable system. The implications that the shape of the transmitting profile has on 3D-display cross talk will be discussed.
An analysis of the basic approaches to flat panel autostereoscopic 3D display is presented, together with a discussion of the application of LCDs in this field. We show that of particular importance in the design of parallax barrier type displays is the diffractive performance of the barriers. A near field diffraction model is used to analyze the detailed illumination structure of the output and can be used to assess viewing freedom and cross talk considerations. A comparison between front and rear parallax barrier displays is given, and compared with experimental result. Recent progress in the design of low cost flat panel 3D displays including a novel viewer position indicator and 2D/3D reconfigurable systems using novel patterned retarder elements are described. We describe the performance and manufacturing considerations for these elements.
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.
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.