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AssigneeKoninklijke Philips Electronics N.V.
InventorsWillem L. Ijzerman, Martin J. J. Jak
Estimating the term…
A display includes a display panel and a backlighting system having a light source and waveguide. The waveguide includes diffusing portions of diffusing material. Light propagates through the waveguide by total internal reflection, but may be scattered by the diffusing portions. Scattered light leaving the waveguide through its exit face produces a pattern of light lines for use in illuminating a 3D autostereoscopic image displayed by the display panel. Intervening portions between the diffusing portions, are formed from a material that can be switched between a light transmissive state and a diffusive state. Optical properties of the intervening portions are controlled using electric fields. Such a display is switchable between a 2D image mode, in which the intervening portions are diffusive and the waveguide provides uniform illumination, and a 3D image mode, in which the intervening portions are transmissive and the waveguide provides illumination in the form of light lines.
A waveguide for use in illuminating a display panel, comprising:
A waveguide for use in illuminating a display panel, comprising:
A display comprising:
A method of presenting an image comprising the acts of:
A method of presenting an image comprising:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Scattering dots or dot-like elements, e.g. microbeads, scattering particles, nanoparticles: provided in the bulk of the light guide
Of the autostereoscopic type: involving lenticular arrays
Illuminating devices: edge-illuminating devices, i.e. illuminating from the side
For viewing without the aid of special glasses, i.e. using autostereoscopic displays: using parallax barriers
Term ended 5 Oct 2025 (estimated)
The present invention relates to a waveguide for use in an autostereoscopic display device.
Light shutter display devices, such as liquid crystal displays (LCDs), in which a backlight is modulated on a pixel-by-pixel basis using a liquid crystal matrix, are well-known. Such devices generally produce a two-dimensional (2D) image. However, rapid progress has been made in the research and development of three-dimensional (3D) displays. For reasons of cost effectiveness and user convenience, display systems that do not require the user to wear special glasses in order to perceive a 3D image have been developed. Such display systems are called autostereoscopic displays.
Autostereoscopic displays typically comprise a conventional display panel, such as an LCD, together with means for providing a pair of images, in which one image is seen by a viewer's left eye and the other is seen by the viewer's right eye. For example, a 3D image can be produced using an array of semi-cylindrical lenses placed in front of the display panel, where the lenses focus light from different columns of pixels or sub-pixels to different regions of space so that a viewer standing at a predetermined distance from the display panel will perceive a 3D image.
Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a known autostereoscopic display arrangement for producing multiple views of an image;
FIG. 2 is a schematic diagram of a display comprising a waveguide according to a first embodiment of the invention;
FIG. 2 depicts a display 8, comprising a display panel 2 and an illumination system comprising a backlight 3, such as a fluorescent rod lamp, and a waveguide 9.
In this example, the display panel 2 comprises a layer of electro-optically active material, such as a liquid crystal material, sandwiched between two light-transmissive substrates (not shown). In the case of a liquid crystal layer, the operation of the layer may be based on, for example, a twisted nematic (TN), super-twisted nematic (STN), vertically aligned nematic (VAN), optically compensated birefringence (OCB), in-plane switching nematics (IPS) or ferro-electric effect for modulating a polarisation direction of incident light. The display panel 2 is subdivided into an array of pixels and is provided with an active matrix or a passive matrix arrangement (not shown) for driving the pixels to allow an image to be displayed in a manner well known per se.
The waveguide 9 comprises an array of portions 10a to 10f of a diffusing material. Examples of suitable diffusive materials include a polymer dispersed liquid crystal (PDLC), which is diffusive in the absence of an electric field and plastics material containing particles of another material for scattering incident light, such as Polymethyl methacrylate (PMMA) containing embedded titanium oxide particles.