Abstract: A controller for a display having a screen which incorporates a light modulator. The screen may be a front projection screen or a rear projection screen. Elements of the light modulator may be controlled by the controller to adjust the intensity of light emanating from corresponding areas on the screen. The display may provide a high dynamic range.

Abstract: A reflective display having a plurality of transparent hemi-beads (120), each having a reflective region (80) surrounding a non-reflective region (82). Each hemi-bead has an associated light absorptive fluid droplet (122) having a normally relaxed shape contacting the non-reflective region, thereby frustrating total internal reflection of light rays at the droplet/hemi-bead interface. An electrical potential is selectably applied across selected droplets. Application of the electrical potential across a droplet deforms the droplet away from the hemi-bead associated with the droplet, such that light rays (158) incident on the non-reflective region are refracted toward substrate (124) and reflected back through hemi-bead (120) in an approximately opposite direction (166); and such that light rays (162) incident on the reflective region are semi-retro-reflected (168). Removal of the electrical potential allows the droplet to resume the relaxed shape.

Abstract: A reflective display having a light reflector (178) incorporating a microlens array (180) and a reflective surface (190). The microlenses redirect light onto reflective regions (194) of the surface. An electrode on the surface has a plurality of annular segments (192), each segment being aligned with a microlens. An electrophoresis medium (204) is contained between the array and the reflective surface. Light absorptive particles are suspended in the medium. An electrical potential source applies an electrical potential across the medium. In the reflective state, the particles are attracted to the electrode segments, leaving the reflective regions substantially unobstructed, and permitting reflection of light by the reflective regions. In the absorptive, non-reflective state the particles are attracted to and distributed across an inward surface (206) of the microlens array. Light which passes through the array is absorbed by the particles at the inward surface of the microlens array.

Abstract: A display has a screen which incorporates a light modulator. The screen may be a front projection screen or a rear-projection screen. The screen is illuminated with light from an illuminator comprising an array of individually-controllable light sources. The light sources and elements of the light modulator may be controlled to adjust the intensity and frequency of light emanating from corresponding areas on the screen. The display may be calibrated to compensate for differences in intensities of the light sources.

Abstract: A display has a screen which incorporates a light modulator. The screen may be a front projection screen or a rear-projection screen. Elements of the light modulator may be controlled to adjust the intensity of light emanating from corresponding areas on the screen. The display may provide a high dynamic range.

Abstract: A reflective display having a plurality of transparent hemi-beads (60), each having a reflective region (80) surrounding a non-reflective region (82). Light absorbing, electrostatically charged ions are dissolved in an electrophoretic medium (20) maintained adjacent the hemi-beads. A voltage applied across the medium moves many ions into an evanescent wave region adjacent the hemi-beads where the ions absorb light, frustrating TIR at the reflective regions. Ions in the evanescent wave region also absorb light which does not undergo TIR and which would otherwise pass through the non-reflective regions. An opposite voltage applied across the medium moves many ions away from the hemi-beads, allowing light to undergo TIR at the reflective regions. The display's brightness can be enhanced by providing a backplane electrode (48) having reflective regions (108; 110, 112) for reflecting back through the hemi-beads light which passes through the non-reflective regions to the backplane electrode.

Abstract: The light emitting surface of an image display light box is formed of multi-layer optical film having a reflectance greater than 95% and preferably about 99% or greater. This more efficiently utilizes light rays emitted by the light box's internal light source, since the multi-layer optical film reflects the light rays many times before the rays are absorbed and lost. Consequently, the light emitting surface can have a light transmissivity characteristic which is macroscopically invariant as a function of position on the light emitting surface. Light boxes utilizing prior art reflective materials require cumbersome, time-consuming, iterative trial and error techniques which must be customized for each light box in order to compensate for light absorption losses by imparting a variable transmissivity characteristic to the reflective material.

Abstract: A display has a screen which incorporates a light modulator. The screen may be a front projection screen or a rear-projection screen. Elements of the light modulator may be controlled to adjust the intensity of light emanating from corresponding areas on the screen. The display may provide a high dynamic range.

Abstract: An optical structure placeable between a backlight array of point light sources and a planar display. The structure distributes light emitted by the point light sources to uniformly illuminate the plane of the display, without introducing significant viewing parallax. The emitted light is partially collimated within a preferred angular viewing range, maximizing the display's luminance when viewed from the normal direction. The structure is highly reflective, such that a substantial portion of any non-emitted light rays are internally reflected by the structure, increasing the likelihood that those rays will be subsequently emitted by the structure.

Abstract: A diffuser incorporates diffuser elements (10) that each include a waveguide (12) coupled between a concentrator (14) and an inverse concentrator (16). The diffuser (44) may be disposed between a backlight (102) and a modulator (114) in a display (100). Luminance ratios of light rays emitted by a low resolution image-forming backlight (102) toward a high resolution light modulator (114) may be preserved such that, for viewing directions within the display's preferred angular viewing range, an observer perceives no significant change in the luminance of displayed images, irrespective of changes in the observer's viewing direction.

Abstract: A diffraction grating for which the intensity and/or direction of the diffracted light is electronically modulated using the electrophoresis of an index-modifying species. Index-modifying dye ions are dissolved in an electrophoretic medium maintained adjacent the diffraction grating. Application of a voltage across the medium moves many of the ions into the region adjacent the grating such that the ions absorb the incident light or otherwise modify the local index of refraction so as to change the optical characteristics of the diffracted light. Application of an opposite voltage across the medium moves many of the ions away from the grating, allowing light rays to diffract in a different manner when encountering the grating.

Abstract: A display comprises a backlight comprising a plurality of individually-controllable light emitters, a light modulator comprising a plurality of individually-controllable elements, and, a retro-reflective optical layer positioned between the backlight and the light modulator. The retro-reflective optical layer is configured to pass light incident thereon at an angle with respect to a normal to the retro-reflective optical layer of less than a threshold angle ?, and reflect light incident thereon at an angle with respect to a normal to the retro-reflective optical layer of greater than ? in a direction opposite and generally parallel to an incoming direction of incident light.

Abstract: A display has a screen which incorporates a light modulator. The screen may be a front projection screen or a rear-projection screen. Elements of the light modulator may be controlled to adjust the intensity of light emanating from corresponding areas on the screen. The display may provide a high dynamic range.

Abstract: Compact fluorescent lamps (CFLs) are characterized by impaired colour rendering, due to their low illumination capability near the blood-red edge of the visible spectrum. Red light output by a light emitting diode (LED) has a relatively narrow spectral distribution, and LEDs are able to produce red light with reasonable efficiency. Blending the light output of a CFL with a small amount of blood-red light emitted by one or more inexpensive LEDs improves colour rendering, while reducing the overall energy cost of operating the CFL-LED hybrid lamp.

Abstract: Methods and apparatus for moving and concentrating particles apply an alternating driving field and an alternating field that alters mobility of the particles. The driving field and mobility-varying field are correlated with one another. The methods and apparatus may be used to concentrate DNA or RNA in a medium, for example. Methods and apparatus for extracting particles from one medium into another involve applying an alternating driving field that causes net drift of the particles from the first medium into the second medium but no net drift of the particles in the second medium.

Abstract: A display has a screen which incorporates a light modulator. The screen may be a front projection screen or a rear-projection screen. Elements of the light modulator may be controlled to adjust the intensity of light emanating from corresponding areas on the screen. The display may provide a high dynamic range.

Abstract: A magnetic levitation apparatus supports a magnetic element in a magnetic field. A control system controls a variable magnetic field to maintain the magnetic element at an equilibrium location relative to an unstable axis. In some embodiments the variable magnetic field has a gradient in the direction of the unstable axis but no field component. In some embodiments the magnetic field is provided by an array of four discrete magnets. In some embodiments additional magnets provide increased field intensity at the equilibrium location this increases stability of the levitated magnetic element against overturning. Light and electrical power may be supplied to the levitating magnetic element.

Abstract: A 3D display has a backlight, image panel, lens array, and aperture mask. The lens array has a plurality of converging lenses having optical axes perpendicular to the image panel. The aperture mask has a plurality of electro-optic elements. Each element is aligned closely proximate to a corresponding one of the lenses and is selectably switchable between “on” to permit passage of light rays through the element, or “off” to prevent passage of light rays through the element. The elements are arranged in subsets of adjacent elements. A controller electronically coupled to the image panel and to the aperture mask repetitively selects an electro-optic element in each subset, switches the selected elements “on”, switches all other elements in each subset “off”, and applies to the image panel a selected plurality of representations of an image, each representation corresponding to a plurality of different viewing directions of the image.

Abstract: Methods and apparatus according to various aspects take as input image data in a lower-dynamic-range (LDR) format and produce as output enhanced image data having a dynamic range greater than that of the input image data (i.e. higher-dynamic range (HDR) image data). In some embodiments, the methods are applied to video data and are performed in real-time (i.e. processing of video frames to enhance the dynamic range of the video frames is completed at least on average at the frame rate of the video signal).

Abstract: Methods and apparatus according to various aspects take as input image data in a lower-dynamic-range (LDR) format and produce as output enhanced image data having a dynamic range greater than that of the input image data (i.e. higher-dynamic range (HDR) image data). In some embodiments, the methods are applied to video data and are performed in real-time (i.e. processing of video frames to enhance the dynamic range of the video frames is completed at least on average at the frame rate of the video signal).