Siebe Tjerk De Zwart

2-D/3-D displays based on switchable lenticulars

— An attractive concept for 3-D displays is the one based on LCDs equipped with lenticular lenses. This enables autostereoscopic multiview 3-D displays without a loss in brightness. A general issue in multiview 3-D displays is their relatively low spatial resolution because the pixels are divided among the different views. To overcome this problem, we have developed switchable displays, using liquid-crystal (LC) filled switchable lenticulars. In this way, it is possible to have a high-brightness 3-D display capable of fully exploiting the native 2-D resolution of the underlying LCD. The feasibility of LC-filled switchable lenticulars was shown in several applications. For applications in which it is advantageous to be able to display 3-D and 2-D content simultaneously, a 42-in. locally switchable prototype having a matrix electrode structure was developed. These displays were realized using cylindrically shaped lenticular lenses in contact with LC. An alternative for these are lenticulars based on gradient-index (GRIN) LC lenses. Preliminary results for such switchable GRIN lenses are presented as well.

Switchable lenticular based 2D/3D displays

The use of an LCD equipped with lenticular lenses is an attractive route to achieve an autostereoscopic multi-view 3D display without losing brightness. However, such a display suffers from a low spatial resolution since the pixels are divided over various views. To overcome this problem we developed switchable displays, using LC-filled switchable lenticulars. In this way it is possible to have a high-brightness 3D display capable to regain the full native 2D resolution of the underlying LCD. We showed the feasibility of LC-filled switchable lenticulars in several applications. For applications in which it is advantageous to be able to display 3D and 2D on the same screen, we made a prototype having a matrix electrode structure. A problem with LC-filled lenses is that in the 2D state there is a residual lens effect at oblique angles. This effect and a possible solution are discussed as well.

28.1: Invited Paper: Multi-view 3D Displays

In this paper we analyze the performance of multi-view barrier and lenticular based 3D displays in their most important display properties, being resolution, brightness, uniformity and cross-talk. We will show that the barrier display is superior in uniformity and that the lenticular is superior in brightness. We will show that the cross-talk and uniformity of an ideal slanted barrier equal that of an ideal defocused lens. for a realistic barrier we will show that diffraction increases the cross-talk but does not change the uniformity. We will also show that the spherical aberrations of the cylindrical lens limit the uniformity of the display but do not affect the cross-talk.

25.2: Invited Paper: The Route Towards a High Efficacy PDP; Influence of Driving Condition, Xe Partial Pressure, and Cell Design

PDP efficacy improvement factors are investigated. It is found that plasma saturation is not limiting the discharge efficiency for practical driving conditions. Key elements for high discharge efficiency are: a high Xe partial pressure, a high sustain voltage and a dedicated cell design. In a color test panel a white luminance of 3500 cd/m2 and an efficacy of 4 lm/W is realized.

Optical design and laser ablation of surface textures: demonstrating total internal reflection

In lighting applications key drivers for optical design of surface textures are integration of optical elements, the disentanglement of optical functionality and appearance and late stage configuration. We investigated excimer laser ablation as a mastering technology for micro textured surfaces, where we targeted an increase in correspondence between surface design and ablated surface for high aspect ratio structures. To achieve this we have improved the photo mask design using a heuristic algorithm that corrects for the angular dependence of the ablation process and the loss of image resolution at ablation depths that exceed the depth of field. Using this approach we have been able to demonstrate close correspondence between designed and ablated facet structures up to 75° inclination at 75 μm depth. These facet design parameters allow for total internal reflection (TIR) as a means of beam deflection which is demonstrated in a range of mono shaped cone arrays in hexagonal tessellation. BSDF analysis was used to characterize the narrow TIR deflection beams that matched the peak positions of the design down to 28° apex. In addition, a single surface TIR-Fresnel lens design with focal distance 5 mm has been manufactured using this photo mask design algorithm and beam collimation up to 12° beam angle and 32° field angle is shown. These outcomes demonstrate that the laser ablation process intrinsically yields sufficient small dispersion in structure and fillet radii for lighting applications.

Enabling eye-contact for home video communication with a multi-view autostereoscopic display

In this paper we present a system for real-time home video communications with multiple users. In order to offer a more natural face-to-face-like communication experience, we have designed a special 3D multi-view display showing different perspectives from different viewing positions. This enables proper directional eye contact and at the same time offers the sense of true physical presence. Our prototype system has clearly shown advantages as compared to existing video communication system for improved naturalness.