Infocus Systems, Inc.

Clarity Visual Systems, Inc.

Microsoft Technology Licensing, LLC

Motorola Corporation

Benjamin R Clifton

Terry J Scheffer

John P Fogarty

Arlie R Conner

Dennis W Prince

Paul E Gulick

John K Grosspietsch

Christopher W L Brandt

Greg A Sorenson

David B Kubeja

William J Leybold

Embodiments of collaborative presentation systems are provided. An example collaborative presentation system includes a display device, an image sensor, a network interface, a logic device, and a storage device holding instructions executable by the logic device to retrieve a presentation file that is executed to display a presentation on the display device, receive image frames from the image sensor, the image frames including the display device, the displayed presentation, and a presenter, and extract the presenter from the image frames to generate an extracted presenter image. The instructions are further executable to adjust an appearance of the extracted presenter image to form an adjusted presenter image, generate an updated presentation file, the updated presentation file being executable to display the presentation overlaid with the adjusted presenter image, and transmit, via the network interface, the updated presentation file to a remote presentation participant device.

Collaborative presentation system

Tilable rear projection display module

A projector (N) of this invention employs a 380 mm diagonal, amorphous silicon LCD () for receiving light rays from a light source (), which achieves a small source size by employing four lamps () with small arc gaps () and a 'pinwheel' mirror () that overlaps light rays from each of the arc lamps into a single collimated light bundle. The small source size produces a small cone angle () of light through the LCD. A lens () directs the narrow cone of light though the LCD at an optimal angle for achieving a 1,500:1 contrast ratio. Only a 4&#xd7; magnification ratio is required to achieve a 170 cm (67 inch) diagonal projected image, which ratio enables projecting SXGA or greater resolution images with a five element projection lens (). The LCD achieves an operational life of at least 50,000 hours before projected images display color degradation.

Image projection system with multiple arc lamps and flyseye lens array light homogenizer directing polychromatic light on a liquid crystal display

A stackable mechanical package for a digitally addressed projector ( N) includes a housing portion ( ) having top and rear surfaces ( ) that are shaped to form a contoured recess ( ), and a pedestal portion ( ) having bottom and front surfaces ( ) that are sized to mate with the contoured recess when the package is in a shippable configuration. When a top side ( ) of the pedestal portion is mated to a bottom side ( ) of the housing portion, the stackable package is in a first operational configuration. Alternatively, when the stackable package is stacked below another similar stackable package ( F), the shippable configuration further forms a second operational configuration. The stackable package includes legs ( ) attached to and protruding from the pedestal portion to support the package apparatus in the first operational configuration or to fasten together the housing and pedestal portions when the package is in the shippable configuration. The fastening employs screws ( ) that pass through mating sets of holes ( ) in the legs and adjacent housing portions, which are then tightened with nuts ( ). Multiple stackable packages may be arrayed vertically and/or horizontally for use in a multiscreen display system ( ).

Interlocking mounting package having separatable chassis for use in multiscreen projection displays

Color gamut and luminance matching techniques for image display systems

An LCD projection display (,) houses a projection module (,) in which light propagates through an LCD module (,) at a shallow angle (,) that improves the contrast ration of and intentionally Keystones the image bearing light. The Keystoned light is reflected by a fold mirror (,) that is mounted at a 52&deg; upward angle, which introduces more intentional Keystoning. A projection lens (,) is mounted coaxial to a tilted optical axis (,), but the Keystoned image bearing light is refracted about 10&deg; off the optical axis and follows a Keystoning axis (,) through the projection lens. The light propagating from the projection lens is reflected by a main fold mirror (,) that is mounted at a 57&deg; angle from the vertical to project the image bearing light onto a 10&deg; slanted projection screen (,). Central light rays (,), image margin light rays (,), and the axial light rays (,) propagate unequal distances from the projection lens to the projection screen and are, therefore, unequally magnified to compensate for the Keystoning introduced by the LCD module. The steep mounting angle of the main fold mirror allows positioning it higher and more forward in the display, which reduces first surface reflections from ambient lighting and allows a significantly reduced depth dimension for the display.

Compact light path and package for liquid crystal projection displays

A liquid crystal display ('LCD') projection unit (12) employs a luminance and color balance system having a lookup table (100) storing multiple sets of gain and/or gamma corrected responses (92-99) for color balance and luminance control. The lookup table values are determined by measuring an S-curve response (90) of an LCD array (40) for each of a set of R, G, and B input data values, converting the S-curve responses to a corresponding set of gamma responses, and scaling the gamma responses to generate red ('R'), green ('G'), and blue ('B') families of gain and gamma corrected values. Color balance is adjusted by selecting the particular R, G, and B families of gain and gamma corrected values that cause the LCD projection unit to match a predetermined ratio of maximum R, G, and B luminance values. Luminance is adjusted by selecting families of lookup table values that adjust the transmittance of the LCD while maintaining the color balance. The LCD projection unit achieves a uniform luminance and color balance that renders it suitable for use in a multiscreen display system (10).

Color and luminance control system for liquid crystal projection displays

A mechanical package for an LCD projector includes approximately equally sized tower and enclosure portions. The tower portion is supported on forward protruding legs and contains optical and electronic modules that slide into its rear and are also accessible from the front of the enclosure portion. The enclosure portion supports on its front a removable projection screen and is mounted vertically offset on the tower portion. A triply folded optical axis provides a suitably long light pathway for projecting a large image on the projection screen without requiring the package to have an undue depth. To stack multiple packages vertically, side margins of the tower portion top surface include L-channels that receive the legs of a package stacked above. The enclosure portion further includes openings that receive the legs protruding from the tower portion stacked above. The legs are supported within the enclosure portion by sliding into U-brackets that are attached to the inner surfaces of the enclosure portion. Fasteners are passed through aligned holes in the legs and U-brackets to secure the vertically stacked packages. To stack multiple packages horizontally, the same fasteners that pass through aligned holes in the legs and U-brackets of the vertically stacked packages are also passed through the corresponding aligned holes in the legs and U-brackets of horizontally adjacent packages.

Stairstep interlock mounting package for multiscreen projection displays

Method and apparatus for providing gray level addressing for passive liquid crystal display (LCD) panels having overlapping row and column electrodes defining pixels are disclosed. Depending upon whether the rows are being addressed by 'standard' or 'Swift' addressing, the signals for applying to the column electrodes are determined by different calculations, in all of which modes the amplitudes of the column signals are related to the gray level desired to be displayed by the individual pixels. For a split interval system, column signals of appropriate amplitude and polarity are applied during different subintervals of a characteristic time interval of the display panel depending upon the method of addressing the rows. In the full interval mode, the column signals applied over a full time interval are based on the desired gray level of all the pixels in the column, adjusted to provide the proper rms voltage across all the pixels so that they display the desired gray levels. The adjustment can be spread across multiple addressing intervals and can be added into the column signal when rows are selected or can be applied to the column electrode when no row is selected.

Gray level addressing for LCDs

An addressing method and apparatus addresses faster responding liquid crystal display panels (LCDs) so that video rate, high information content LCDs having time constants on the order of 50 ms or less are perceived as having improved contrast by limiting peak voltage levels across the pixels. In a preferred embodiment, a first set of LCD electrodes is continuously driven with signals each comprising a train of pulses that are periodic in time, have a common period T, are independent of the information to be displayed, and are preferably orthonormal. Plural column signals are generated from the collective information states of the pixels defined by the overlap with a second electrode pattern. Each column signal is proportional to the sum, obtained by considering each pixel in the column, of the exclusive-or (XOR) products of the logic level of the amplitude of each row signal times the logic level of the information state of the pixel corresponding to that row. Hardware implementation comprises an external video source, a controller that receives and formats video data and timing information, a storage device that stores display data, a row signal generator, a column signal generator, and at least one LCD panel. Alternative embodiments provide circuits to reduce the number of column voltage levels required to generate a displayed image.

Displaying gray shades on display panel implemented with phase-displaced

Method and apparatus for providing gray level addressing for passive liquid crystal display (LCD) panels having overlapping row and column electrodes defining pixels are disclosed. Depending upon whether the rows are being addressed by 'standard' or 'Swift' addressing, the signals for applying to the column electrodes are determined by different calculations, in all of which modes the amplitudes of the column signals are related to the gray level desired to be displayed by the individual pixels. For a split interval system, column signals of appropriate amplitude and polarity are applied during different subintervals of a characteristic time interval of the display panel depending upon the method of addressing the rows. In the full interval mode, the column signals applied over a full time interval are based on the desired gray level of all the pixels in the column, adjusted to provide the proper rms voltage across all the pixels so that they display the desired gray levels.

Method and apparatus are disclosed for providing gray level addressing for passive matrix liquid crystal display (LCD) panels having pixels defined by overlapping row and column electrodes. The pixels have optical states determined by the rms voltage appearing across the pixels during a frame period. The frame period is divided into characteristic time intervals, which are further divided into sub-intervals. The amplitude of the column signals during each of the sub-intervals is determined from the desired gray level of the pixel or pixels defined by the corresponding column electrode and selected one or ones of the row electrodes.

Split interval gray level addressing for LCDs

The invention identifies the cause of and solves so-called display pattern splicing in passive matrix displays implemented with Active Addressing.TM. techniques or other techniques that produce column signals having more than one magnitude. Splicing is an optical aberration that is manifested by a transient pixel rms voltage deviation from a current, frame-averaged value that occurs when one image changes to a new one. Active solutions to display pattern splicing apply a correction of some type to counteract the effects of the transient optical response. Preferred active solutions are premised on the observation that splicing is an effect common to all pixels on a column. One type of active solution includes different embodiments that entail determining the amplitude and character of the display pattern splice and introducing a compensating signal as a function of the amplitude and character of the splice to counteract it. One embodiment modifies the column signal values applied to the column electrodes, and another embodiment adds correction time intervals to a frame period to adjust the rms voltages of the column signals applied during the frame period.

Methods and systems for detecting and correcting dynamic crosstalk

Different gray shades or hues may be displayed in accordance with an active addressing technique that addresses faster responding passive matrix liquid crystal display panels (LCDs) so that video rate, high information content LCDs are perceived as having improved contrast by limiting peak voltage levels across the pixels. A preferred embodiment of the active addressing technique is implemented such that a first set of LCD electrodes is continuously driven with signals each comprising a train of pulses that are periodic in time, have a common period T, are independent of the information to be displayed, and are preferably orthonormal. Multiple column signals are generated from the collective information states of the pixels defined by the overlap with a second electrode pattern. Each column signal is proportional to the sum, obtained by considering each pixel in the column, of the exclusive-or (XOR) products of the logic level of the amplitude of each row signal times the logic level of the information state of the pixel corresponding to that row. Two alternative gray shading techniques provide for intermediate optical states between light and dark states. A frame modulation technique uses several frame periods to control the proportion of time a pixel is light or dark. A pulse width modulation technique subdivides an addressing time interval to control the proportion of time a pixel is light or dark during the addressing time interval. Either technique addresses the pixel to an intermediate optical state.

Growing community of inventors

Oregon City, OR, United States of America

Benjamin R Clifton