Other

L-3 Communications Corporation

Palomar Technologies, Inc.

Hughes Aircraft Company

Litton Systems, Inc.

Randall D Blanchard

Eugene W Cross, Jr

Ronald D Shirley

A stereoscopic imaging assembly for converting true visual images of a real-life subject to a stereoscopic image includes a display and an analyzer. The display is preferably a liquid crystal display, which includes first image pixels, second image pixels, and a polarizer. The first image pixels are responsive to a first electronic image of a first true visual image and the second image pixels are responsive to a second electronic image of a second true visual image. The polarizer has a first polarization material, which enables transmission of light of a first polarity, while blocking light of a second polarity, thereby transmitting a first polarized image having a first polarity. A second polarization material enables transmission of light of the second polarity, while blocking light of the first polarity, thereby transmitting a second polarized image having a second polarity. The analyzer delivers the first polarized image to the first eye of an observer while excluding the second and delivers the second polarized image to the second eye while excluding the first, which enables the observer to synthesize the first and second polarized images into a stereoscopic visual image.

Stereoscopic imaging assembly employing a flat panel display

Sunlight can damage a conventional touch screen display and cause the display to be quite difficult to read. Furthermore, conventional touch screen displays are easily damaged, and, once damaged, the entire touch screen is replaced. To address these concerns, a touch panel includes anti-reflective coatings on the surfaces of the top plate and the base plate that are open to the air. These coatings substantially reduce reflections and make the touch screen easier to read in direct sunlight. In particular, the anti-reflective coating used on the upper surface of the base plate is dielectric in nature to reduce reflectivity even further. This dielectric coating includes openings to an underlying conductive layer so that an electrical contact is made when a user deflects the top plate into the base plate. Also, the top plate may be detachably coupled to the base plate, advantageously by double stick adhesive tape, so that only the top plate is replaced when damaged. In one embodiment, the top plate is placed in tension within a frame to prevent wrinkling. Furthermore, a resistive voltage divider may be fabricated on the base plate. The resistive voltage divider may include a substantially continuous strip of resistive material disposed on the conductive layer of the base plate, and a plurality of conductive traces disposed on the dielectric layer of the base plate and coupled to the resistive material in selected locations.

Resistive touch panel using removable, tensioned top layer

An illumination device is provided, which includes, in series, a fluorescing radiation source, a light selective filter, and a light source. The light selective filter is relatively transmissive of fluorescing radiation and relatively reflective of light. The light source is preferably a fluorescable phosphor. The illumination device further includes in series after the light source, a fluorescing radiation selective filter which is relatively transmissive of light and relatively reflective of fluorescing radiation. The illumination device may be one of several specific devices, such as a fluorescent lamp assembly, a flat panel display backlight assembly, or a white light-emitting diode assembly.

Illumination device having a dichroic mirror

The present technique relates to a method and apparatus of illuminating a display, which has a display screen, a plurality of lamps and reflector containing both specular and diffuse surfaces. The technique provides a relatively small area specular reflector with a curved surface configured for reflecting a substantial amount of light away from the lamps, into the intermediate areas between the lamps, and toward the display screen. The relatively large remaining area of the reflector provides a diffuse surface to direct some amount of light away from the lamps and toward the display. In addition, this diffuse surface optimizes the performance of light control films integral to the illumination system.

Display system using a hybrid backlight reflector

Ambient light can saturate the light detectors of a touch screen and cause unreliable operation. To address this concern, one or more filters may be placed proximate the detectors. A first filter may be a spatial filter, such as a microlouvre filter. A microlouvre filter is arranged so that it passes light transmitted by the light detectors and rejects off-axis light. Another filter may be a narrow band optical filter, such as a dichroic notch filter. Such an optical filter passes light having wavelengths within a narrow band selected to correspond to the spectral characteristics of the light emitters, while it rejects light of other wavelengths. The spatial filter and the narrow band optical filter may be used separately or in combination.

Infrared touch panel with improved sunlight rejection

An apparatus is disclosed that provides back light for liquid crystal displays (&ldquo;LCD&rdquo;). The apparatus includes an electrodeless lamp disposed in a cabinet for generating light; and a reflector disposed on one side of the electrodeless lamp for directing light from the lamp in the direction of the LCD. The reflector further includes a surface profile that provides a uniform distribution of light intensity into the LCD. The reflector further is adjacent and in near contact with the lamp to provide a minimum depth behind the lamp. An alternate embodiment of the invention includes an IR reflector disposed between the electrodeless lamp and a diffuser, which is located adjacent the LCD screen.

Low profile backlight optimized for liquid crystal displays

An apparatus for controlling the brightness of an electrodeless fluorescent lamp excited by power supplied to a coil disposed in closed proximity to said lamp. The apparatus includes a dimming control unit responsive to a brightness setting for the lamp that provides a PWM signal indicative of the brightness setting. An oscillator is disposed for producing a first lamp drive voltage having a first frequency selected in response to a first state of the PWM signal and a second lamp drive voltage having a second frequency selected in response to a second state of the PWM signal. Accordingly, the first drive voltage turns on the lamp by transferring maximum power to the lamp and the second drive voltage turns off the lamp by transferring minimum power to the lamp.

Dimmable ballast for electrodeless fluorescent lamps

A display device ( ) is comprised of a display unit ( ) and a high efficiency backlight assembly ( ). The backlight assembly ( ) is comprised of an inductively coupled electrodless fluorescent lamp ( ) for providing light to the display unit ( ). The display unit ( ) includes a liquid crystal display (LCD) element ( ) for displaying an image and a diffuser ( ) for using the light generated by the backlight unit ( ) to create a relatively uniform level of brightness over the entire area of the LCD element ( ). The electrodless lamp ( ) is preferably mounted in a reflective lamp housing ( ) having a reflective lamp lining ( ) designed to provide uniform illumination intensity on the LCD element ( ). The electrodless lamp ( ) may have a rectangular shape and a center reflector ( ) mounted within the rectangular opening to further direct light toward the LCD element ( ). In a further version of the invention, a backlight unit ( ) is comprised of a light guide ( ) having remote electrodless lamps optically connected to the ends ( ) thereof.

Liquid crystal display device using an electrodless fluorescent lamp

Sunlight can damage a conventional touch screen display and cause the display to be quite difficult to read. Furthermore, conventional touch screen displays are easily damaged, and, once damaged, the entire touch screen is replaced. To address these concerns, a touch panel includes anti-reflective coatings on the surfaces of the top plate and the base plate that are open to the air. These coatings substantially reduce reflections and make the touch screen easier to read in direct sunlight. In particular, the anti-reflective coating used on the upper surface of the base plate is dielectric in nature to reduce reflectivity even further. This dielectric coating includes openings to an underlying conductive layer so that an electrical contact is made when a user deflects the top plate into the base plate. Also, the top plate may be detachably coupled to the base plate, advantageously by double stick adhesive tape, so that only the top plate is replaced when damaged. Furthermore, a resistive voltage divider may be fabricated on the base plate. The resistive voltage divider may include a substantially continuous strip of resistive material disposed on the conductive layer of the base plate, and a plurality of conductive traces disposed on the dielectric layer of the base plate and coupled to the resistive material in selected locations.

Touch panel with improved optical performance

A projection display system is provided having a first off-axis projector, a second off-axis projector and a screen assembly including a display screen. The screen assembly has a center axis segmenting the assembly into two segments. The first off-axis projector produces a first image that is directed via a first image path onto the first segment of the screen assembly and the second off-axis projector produces a second image that is directed via a second image path onto the second segment of the screen assembly. The second image interfaces the first image at the center axis of the screen assembly, both images intersecting the center axis at a substantially normal angle. The screen assembly may further include a Fresnel lens positioned in the first and second image paths adjacent to the display screen for receiving and straightening the first and second images. The first and second images are tiled across the entirety of the rear face of the screen assembly. The configuration of adjacent first and second off-axis projectors enables near perfect optical alignment of the first and second images, with the seam at the interface of the first and second images virtually indistinguishable to the viewer. An alternate embodiment of the system employs four off-axis projectors tiling four images across the rear face of a screen assembly in a similar manner.

System for displaying images from multiple projectors onto a common

The drive voltage (V.sub.DATA -V.sub.REF) across an active matrix liquid crystal display module (24) is reversed on alternate frames or alternate lines by using a fixed voltage level (V.sub.REF) at one side of the LCD module and shifting the level of a base component (V.sub.BASE) on the other side of the module between higher and lower voltage levels that are respectively higher than the fixed reference level and lower than the fixed reference level. All voltages have the same polarity so that polarity shifting of any applied voltage is not required. An intensity level component from a digital to analog converter (40a), controlled by a digital input code (41), is combined with the base component in the same sense in alternate frames, but with the digital input code inverted in alternate frames.

Liquid crystal display drive with voltage translation

A flat panel liquid crystal display module (34) has its front face adjacent a rear projection screen (40) and is illuminated by a pre-polarized collimated light source (10,14,16,18,22,26). Collimation is provided by either a Fresnel lens or a projection lens having a long focal length. The characteristics of the projection screen (40) provide narrowed vertical viewing angle and a fiber optic face plate (38) between the liquid crystal module (34) and the screen (40) provides sunlight rejection. The arrangement has greatly improved display brightness, with only minimal changes in contrast and color as viewing angle changes.

Flat panel display with elliptical diffuser and fiber optic plate

A projection system having a rear projection screen (28) employs a collimating lens (26) in the form of a Fresnel lens adjacent the rear surface of the screen (28) to improve the image luminance at various viewing angles and provide uniform brightness over the area of the screen. A fiber optic face plate (30) or two crossed films of microlouver light control material is interposed between the collimating Fresnel lens (26) and the rear of the projection screen (28) to provide a high degree of blocking of high intensity light, such as sunlight, that may impinge upon the front of the screen. The optical fibers (42) of the fiber optic face plate have a low numerical aperture and an opaque cladding. The arrangement allows an image to be provided on the screen with high contrast even in the presence of sunlight striking the screen.

Rear projection screen with high off-axis sunlight rejection

A display screen of a projection system embodying a cathode ray tube, liquid crystal light valve, laser or the like is formed of a plastic sheet (22, 22a) that has embedded therein a number of microsphere diffuser particles (24, 24a) initially having a spherical shape and distributed in a uniformly isotropic density. The plastic sheet and its embedded particles are heated and stretched in a single direction and allowed to cool in their elongated form so that the diffuser particles (24a) then have an elongated elliptical shape and a density that is greater along one axis than it is along an orthogonal axis. The particle elongation and decreased density in the direction of stretch cause the diffusing sheet to have a diffusion cone angle (44), as measured in a plane containing the axis of stretch, that is significantly decreased, but with increased screen gain, whereas the diffusion angle (42) in the orthogonal unstretched direction remains relatively large, and also has an increased screen gain. The decreased diffusion angle is oriented in a vertical direction in a common display because the viewer's eye, in looking at a display screen, is most commonly positioned within a relatively small vertical cone angle, although the horizontal angle of view may be considerably larger.

Growing community of inventors

San Diego, CA, United States of America

Randall D Blanchard