Oscar Hendrikus Willemsen

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.

2‐D/3‐D switchable displays

— In this paper, the design of a lenticular-based 2-D/3-D display for mobile applications is described. This display combines look-around capability with good 3-D resolution. In order to allow high-resolution datagraphic applications, a concept based on actively switched lenses has been developed. A very noticeable problem for such displays is the occurrence of dark bands. Despite slanting the lenticular and defocusing the lens, banding becomes unacceptable when the display is viewed from an angle. As a solution, fractional viewing systems to reduce the banding intensity by almost two orders of magnitude is introduced. The resulting 3-D display can be viewed from any horizontal direction without banding.

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.

20.1: Locally Switchable 3D Displays

3D displays will drastically enhance the viewing experience of future displays for many applications. Unfortunately, 3D displays generally have a lower resolution since the pixels are divided over more views. Therefore, some 3D displays have the opportunity to switch between 2D and 3D mode such that either natural 3D images or high-resolution 2D images can be displayed. However, especially for mobile applications it is advantageous to be able to display 3D and 2D at the same time. In this paper we will discuss the design and driving of locally switchable lenticulars, which combines perfect high-resolution 2D with natural 3D areas.

LED-based mini-projectors

We have built a mini-projector with LED light sources that is sufficiently small for portable applications. The projector has a three-panel architecture with transmissive LCD micro-displays in order to combine a high lumen output with a low cost price. The volume of the light engine is 100 cc.

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.

58.4: A Handheld Mini-Projector Using LED Light Sources

We have built a mini-projector with LED light sources that is sufficiently small for portable applications. The projector has a three panel architecture with transmissive LCD micro-displays in order to combine a high lumen output with a low cost price. The volume of the light engine is 110 cc. The projector can deliver up to 15 lumen to the screen at a LED power of 9 W. In the high efficiency mode the output is 8.5 lumen at 3.8 W.

The Fast Intelligent Tracking (F!T) tube: A CRT without a shadow mask

The F!T tube is a new type of CRT without a shadow mask. The primary function of the mask, color selection, is taken over by an electronic control system that guides the electron beams over the correct phosphor lines. The position of the beams is detected by means of dedicated structures on the faceplate. Proof of the principle has been shown in single- and triple-beam 17- and 32-in. tubes.

44.1: The Fast Intelligent Tracking (F!T) Tube: A CRT without a Shadow Mask

The F!T tube is a new type of CRT without a shadow mask. The primary function of the mask, color selection, is taken over by an electronic control system that guides the electron beams over the correct phosphor lines. The position of the beams is detected by means of dedicated structures on the faceplate. Proof of the principle has been shown in single- and triple-beam 17″ and 32″ tubes.

Tracking system of the Fast-Intelligent-Tracking (F!T) tube

In this paper, we describe the principles of the tracking system of the Fast Intelligent Tracking (FIT) tube. We will show how the tracking system is divided in a fast-responding system and a slowly responding system, according to the observed deviations of the beam positions from their intended positions.