Texas Instruments Corporation

Other

Adam J Kunzman

Kazuhiro Ohara

Hisakazu Hitomi

Dana J Segler, Jr

Hideki Ohmae

Robert J Gove

Gregory Scott Pettitt

William B Werner

Keith Harold Elliott

Satyan R Kalyandurg

An apparatus and method for reducing the moir&#xe9; effect in rear-projection displays by rotating the dark-stripe structure () in the screen () 45&#xb1;15 degrees relative to the displayed pixel structure. By rotating the dark-stripes () relative to the displayed pixels, the spatial frequency at which the moir&#xe9; effect sets in can be improved by 15% to 41%.

Reduction or moir&#xe9; effect in pixelated rear-projection displays

A display system ( ) in which light from source ( ) is focused onto a spinning color wheel ( ). The spinning color wheel ( ) spins at a constant rate and creates of beam of light that changes from one primary color to the next in rapid sequence. The primary colored beam of light impinges a spatial light modulator ( ), which is often a DMD or LCD. A controller ( ) receives an input video signal and determines the native frame rate of the image source. The controller ( ) sends image data to the spatial light modulator ( ) in synchronization with the color wheel ( )&mdash;image data representing the red portions of the image is sent during the period in which the red color filter is passing through the beam of light&mdash;at the native frame rate of the image source. The modulated light is focused onto an image plane ( ) by projection lens ( ) to form an image. The eye of the viewer integrates the sequential primary color images giving the perception of a single full-color image. The display system uses a single nominal color wheel speed to display input signals having various native frame rates. The nominal color wheel speed is selected to allow the same color wheel rate to be used for a variety of native frame rates. The color wheel speed is selected to provide a sub-frame rate that is an integer multiple the native frame rate of each potential input format.

Color wheel synchronization in multi-frame-rate display systems

An apparatus and method for reducing the moir&eacute; effect in rear-projection displays by rotating the dark-stripe structure ( ) in the screen ( ) 45&plusmn;15 degrees relative to the displayed pixel structure. By rotating the dark-stripes ( ) relative to the displayed pixels, the spatial frequency at which the moir&eacute; effect sets in can be improved by 15% to 41%.

Reduction of moire effect in pixelated rear-projection displays

A tone display method which prevents degradation in image quality of moving images when the subfield method is utilized without an increase in cost. When tone display is performed with 256 tones with respect to one certain color, in each frame, segments 1 to 6 in time are set corresponding to the plural time-shared time bands of the color and each segment includes one or several subfields (sf). In each case, as the tone is increased by 42 (or 43) for segments 1 through 6, sequentially, the subfields in the segment being lit so that the tone is increased continuously. In each segment, the display is performed mostly according to the binary method for the subfields

Tone display method

A display system in which light from source ( ) is focused onto a spinning color wheel ( ). The spinning color wheel ( ) creates of beam of light that changes from one primary color to the next in rapid sequence. The primary colored beam of light impinges a spatial light modulator ( ), in this case a DMD. A controller ( ) receives an input video signal and sends image data to the spatial light modulator ( ) in synchronization with the color wheel ( )&mdash;image data representing the red portions of the image is sent during the period in which the red color filter is passing through the beam of light. The modulated red beam of light is focused onto an image plane ( ) by projection lens ( ) to form a red image. The process repeats as the green and blue filters pass through the path of the light beam. The eye of the viewer integrates the three primary color images giving the perception of a single full-color image. The display system uses a single nominal color wheel speed to display input signals having various frame rates. The nominal color wheel speed is selected to allow the same color wheel rate to be used for a variety of input frame rates. The color wheel speed is selected to provide a sub-frame rate that is an integer multiple the frame rate of each potential input format.

Common color wheel speed system

A method and apparatus for reducing the color separation in sequential color display systems. The disclosed approach adds a white (clear) segment to the color filtering system and applies an algorithm, which separates the luminance channel as much as possible into this white segment. As a result, in the case of a black-and-white image where color separation is most visible, color segments will have a minimal amount of energy in them, thereby reducing the color separation effect. The algorithm controls the process of transferring the energy from the colored segments into the white segment and also allows for a dynamic mode, where on a pixel-by-pixel basis, both color separation reduction is made for the white portions of the image and overall image brightness is improved in the non-white (color) portions of the image.

Reduced color separation white enhancement for sequential color displays

A display system using red, green, blue, and white light. The system derives data for the white portion of a color wheel or a white device from the red, green and blue data. The white portion of the color wheel is controlled as if it were another primary color on the wheel. Errors are prevented by a correction applied if the unfiltered light from the source has a different color temperature than the white light produced using the red, green and blue segments of the color wheel, or the devices for those colors. Analysis is performed on the data to determine if white light is necessary to be added to each frame of data.

High brightness digital display system

A tone display method is provided that can prevent image quality deterioration of the dynamic image and can avoid a cost increase. When an image with 256 tones is displayed, one field is divided into 37 subfields for one color. Among the 8 bits corresponding to the 256 tones, the six high-order bits from the third bit are displayed by means of time width modulation using 35 subfields SF,-SF,having weights of &ldquo;&ldquo;4&rdquo; and &ldquo;8&rdquo;. The two low-order bits are displayed on a binary base using two subfields SF,and SF,whose weights are &ldquo;'1&rdquo; and &ldquo;2&rdquo;, respectively.

Adaptive white light enhancement for displays

A formatter and frame buffer unit (20) for a display system (10) that uses a spatial light modulator (16) to display data formatted in bit-planes. Formatters (21) convert multi-bit pixel data to bit-plane data. The frame buffer memory (25) is comprised of conventional DRAM devices. To allow the use of DRAMs, formatters (21) operate on a number of consecutive pixels, the number of pixels being sufficient for an extended page mode form of addressing the DRAMs.

DRAM bit-plane buffer for digital display system

Method of calibrating a color wheel system having a clear segment

Electronically programmable color wheel

A baseline display system (10) is capable of receiving different types of input signals, analog or digital, having different horizontal and vertical input resolutions. The system uses serial video processors (SVPs) (33, 34, 43, 83) that have a given input size and spatial light modulators (SLMs) (18) that have a given output (display) resolution- The baseline system (10) is configurable to meet bandwidth requirements for displaying real time images on SLMs of increasing resolution. Data is decimated (downscaled) when appropriate to fit the SVP input size (FIGS. 4 and 8) and upscaled, vertically or horizontally, when appropriate to fit the SLM display resolution (FIGS. 3, 4, 7, and 8). Four systems (20, 50, 60, 90) , each appropriate for a different SLM resolution are described.

Growing community of inventors

Fairview, TX, United States of America

Adam J Kunzman