Disclosed is a light guiding valve apparatus including an imaging directional backlight, an illuminator array and an observer tracking system arranged to achieve control of an array of illuminators which may provide a directional display to an observer over a wide lateral and longitudinal viewing range, wherein the number of optical windows presented to the observer as viewing windows is controlled dependent on the lateral and longitudinal position or speed of an observer.

Directional display apparatus

A compact backlighting system for illuminating a display device (12) comprises a light-emitting panel (1) having a front wall (2), an opposing rear wall (3) and edge areas (4) At least one of the edge areas (4) is capable of transmitting light The backlighting system includes a light source (6) comprising at least one LED, and a light-mixing panel 5 for mixing the light originating from the light source (6) Light originating from the light source (6) is coupled into the light-mixing panel (5) via a light input surface (7), which light is mixed in the light-mixing panel (5) and coupled out via a light output surface (8) The light-mixing panel (5) and the light-emitting panel (1) are arranged so as to extend substantially parallel to each other Between the light-mixing panel 5 and the light-emitting panel 1, the backlighting system comprises a light transport chamber (9) for transporting the light from the light-mixing panel (5) to the light-emitting panel (1) Preferably, the light transport chamber (9) has an elliptical, reflective inner wall (10)

Compact illumination system and display device

Disclosed is an optical valve or light valve for providing large area collimated illumination from localized light sources, and system and method thereof for 2D, 3D, and/or autosteroscopic displays An optical valve may include a stepped structure, in which the steps include separated extraction features which may be optically hidden to light propagating in a first direction Light propagating in a second direction may be refracted, diffracted, or reflected by the features to provide illumination beams exiting from the top surface of the optical valve Such controlled illumination may provide for efficient, multi-user autostereoscopic displays as well as improved 2D display functionality

Directional flat illuminators

The application of microstructures which improve the quality of light available to the viewer of an optical display system, or any display (100) which works on the concept of moving one surface into direct contact or close proximity of a light guide (201, 403, 505, 706, 806, 902, 1201, 1408, 1502) to extract light through frustrated total internal reflection. Optical microstructures are introduced on one or both of the surfaces of the active layer (202, 404, 506, 604, 704, 1501) to enhance its performance.

Optical microstructures for light extraction and control

A brightness enhancement film comprises an array of tapered structures, each said tapered structure having a light input aperture and a larger light output aperture. The inner side-wall of each said tapered structure is adapted to reflect off-axis light from the light guiding plate incident at said input aperture to said output aperture.

Brightness enhancement film using light concentrator array

A collimator is provided to collimate light from a lambertian light source in which light from a fluorescent lamp is reflected towards an exit slit and in which light which leaves the slit at 180 degrees and is collimated in one direction to +/−1/2 degree. The collimator is utilized in one application to maximize the diffraction efficiency of a diffractive color separator microlens array to increase the brightness of a color liquid crystal display and to increase color saturation. In order to provide collimation, the light exiting the exit slit is collimated by parabolic surfaces of an optical waveguide to provide a beam which has a collimation of +/−3 degrees in one direction. This light in one embodiment is spread out by a reflective array and is further collimated by a cylindrical lens array so that it exits a panel with the required +/−1/2 degree collimation.

Light collimator for liquid crystal displays

A high brightness, high color saturation liquid crystal display permits direct sunlight viewing. The display includes one or more diffractive color separation microlenses, in one embodiment, trimodal, which serves both to spatially separate incoming white light into red, green and blue bands and to focus the bands onto a subpixel matrix. A stepped and segmented surface of at least one microlens enables that microlens to provide a plurality of diffraction patterns.

Sunlight viewable color liquid crystal display using diffractive color separation microlenses

A system is provided for increasing the brightness and color saturation of a liquid crystal display to permit direct sunlight viewing which includes the utilization of an array of diffractive color separation microlenses which serve both to spatially separate incoming white light into red, green and blue bands which do not overlap and to focus the bands onto a subpixel matrix such that each of the sub-pixels is illuminated with only one color. The diffractive color separation is made possible through the utilization of the iterative genetic algorithm which specifies the stepped surface of the lens that provide for exceptionally fine color separation. In one embodiment the genetic algorithm is applied iteratively to define the optimal stepped surfaces which are utilized to focus the various colors at different positions at the focal plane of the lens. The subject system improves the overall transmission efficiency of 5% for a standard liquid crystal display to in excess of 30% overall efficiency. This results in lower power requirements or alternatively a brighter display such that the displays are sunlight viewable and have application in lap top computers, cockpit displays, automobile instrument displays, ATM displays, projection displays, equipment displays, and in general any display of a color LCD nature which is to be viewed in direct sunlight.

Color liquid crystal display having diffractive color separation microlenses

At the Cockpit Displays III & IV conference, diffractive color separation was proposed as a means for improving both the performance and efficiency of liquid crystal displays. This paper discusses that approach in further detail as well as the progress made in attempting to develop the necessary technology. A design for the color separator filter was made based around the use of an analog and binary fabrication technologies. Performance of the two resulting color separation filters will be discussed.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Diffractive color separation fabrication

At the Cockpit Displays III conference, diffractive color separation was proposed as a means for improving both the performance and efficiency of liquid crystal displays. This paper discusses that approach in further detail as well as the progress made in attempting to develop the necessary technology. Specifically, progress has been made on two fronts: the development of the color separation element and the development of a low divergence backlight suitable for avionics direct view applications. The approach taken in these two developments is described as well as the current state of the development.

Thomas V. Gunn

Papers

Light collimator for liquid crystal displays

Sunlight viewable color liquid crystal display using diffractive color separation microlenses

Color liquid crystal display having diffractive color separation microlenses

Diffractive color separation fabrication

Diffractive color separation for high-efficiency LCDs