Method of and device for displaying images on a display device

• US 7,071,894 B1
• Filed: 04/19/2000
• Issued: 07/04/2006
• Est. Priority Date: 04/28/1999
• Status: Expired due to Term

• Current Assignee: Naamloze Vennootschap Barco
• Original Assignee: Naamloze Vennootschap Barco
• Inventors: Thielemans, Robbie, Gerets, Peter
• Primary Examiner(s): Shalwala, Bipin
• Assistant Examiner(s): DHARIA, PRABODH M
• Application Number:
  US09/926,408
• Time in Patent Office: 2,267 Days
• Field of Search: 345 11- 13, 345/3.1, 345/3.4, 345/204, 345/87, 715/751, 713/501
• US Class Current: 345/1.1
• CPC Class Codes: G06F 3/1446 display composed of modules, e.g. video walls
• CPC Class Codes: G06F 3/147 using display panels
• CPC Class Codes: G09F 9/3026 Video wall, i.e. stackable semiconductor matrix display modules video wall control systems G06F3/1446, G09G2300/026
• CPC Class Codes: G09G 2300/026 Video wall, i.e. juxtaposition of a plurality of screens to create a display screen of bigger dimensions
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2320/043 Preventing or counteracting the effects of ageing
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2340/0407 Resolution change, inclusive of the use of different resolutions for different screen areas
• CPC Class Codes: G09G 2360/02 Graphics controller able to handle multiple formats, e.g. input or output formats
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: G09G 5/18 Timing circuits for raster scan displays specially adapted for television H04N ; synchronisation between the display unit and other display units, videodisc player G09G5/12

Abstract

A method for displaying images on a display device. The display device includes a general processing unit, a display having several display units and an individual processing unit per display unit. In order to display the images, data concerning the image to be displayed are transmitted from the general processing unit to the individual processing units in the form of a data stream, in that there is a control communication between the general processing unit and each of the individual processing units in the form of control signals. The data from the data stream are collected at every individual processing unit as a function of the control signals transmitted to the individual processing units.

Claims

1. A method for displaying images on a display device, the display device including at least one general processing unit and a display comprising a plurality of display units with corresponding processing units, the method comprising the steps of:

transmitting a data stream comprising data concerning the image to be displayed from the general processing unit to the individual processing units;

providing a control communication comprising a plurality of control signals between the general processing unit and each of the individual processing units, the control communication sent from the general processing unit to each of the individual processing units being individually distinct from the data stream sent to each processing unit;

collecting data from the data stream at each of the individual processing units as a function of control signals transmitted to the individual processing units;

providing distributed signal processing between the general processing unit and the individual processing units;

providing a distributed signal processing for the signals related to the image display; and

raising the line frequency in the general processing unit in order to eliminate interline flicker and to obtain higher image resolution.

2. The method according to claim 1, wherein the display units are serially coupled.

3. The method according to claim 1, wherein the display units consist of LED panels.

4. The method according to claim 1, wherein the distributed signal processing is at least provided for signals related to color rendering, and/or brightness, and/or contrast.

5. The method according to claim 4, further comprising the step of making at least one individual adjustment at the individual processing units, said at least one individual adjustment being selected from the group consisting of:

adjustment of the color coordinates, adjustment of brightness, adjustment of contrast by dynamic sample weight distribution, corrective adjustment as a function of the temperature and/or age of the display unit, adjustment of the transfer functions, and enlargement of the incoming video signal in the horizontal direction and/or vertical direction.

6. The method according to claim 5, wherein contrast adjustment comprises adjusting the linear connection between the input signal and the output signal towards a non-linear connection in each individual processing unit as a function of the command provided by the control signals.

7. The method according to claim 5, wherein at least one individual adjustment is made at the general processing unit, said adjustment being selected from the group consisting of:

image stabilization and/or noise suppression, tracking of the illumination of the image, histogram equalization as a function of the entire image to be displayed, observing a cue flash and making a correction, and reduction of the image in relation to the original input image in the horizontal direction and/or vertical direction.

8. The method according to claim 1, further comprising the step of providing distributed signal processing to minimize image flickering of the general processing unit and the individual processing units.

9. The method according to claim 1, further comprising the step of making individual adjustments to maintain the display unit in operating frequency-independent both vertically and horizontally.

10. The method according to claim 1, wherein an automatic pulse width adjustment is realized in the individual processing units.

11. The method according to claim 1, further comprising the step of raising a frequency in the individual processing units to eliminate surface flicker.

12. The method according to claim 1, further comprising the step of providing distributed signal processing at least for signals which determine image geometry.

13. The method according to claim 12, further comprising the step of transmitting control signals to the individual processing units to indicate which part of the image should be displayed at the display unit, the individual processing units collecting data from the data stream, processing the data and displaying the data as a function of the control signals.

14. The method according to claim 1, comprising the step of providing for dynamic image stabilization.

15. The method according to claim 14, wherein at least one technique is applied for the dynamic image stabilization, said at least one technique being selected from the group consisting of:

a time-dependent image stabilization arranged for verifying pixels of an image and including determining alterations occurring between successive images and providing an image stabilization effect before the images are displayed;

a frequency dependent image stabilization arranged for verifying how alterations occur in pixels of an image positioned next to one another and providing an image stabilization effect before the images are displayed;

an amplitude-dependent image stabilization; and

an image stabilization as a function of an entire image content.

16. The method according to claim 1, wherein the individual processing units are provided with master clock correction.

17. The method according to claim 16, wherein different signals are used for red, green and blue signals, and transmission errors in the red, green and blue signals are minimized due to the master clock correction.

18. The method according to claim 1, wherein the display includes a plurality of LEDs driven by an uninterrupted current during operation such that the length of time for which the current is switched on is used as a control parameter.

19. The method according to claim 18, wherein the current is altered to adjust the brightness and the contrast.

20. The method according to claim 1, wherein the data stream and the control signals are transmitted via separate data lines.

21. The method according to claim 1, wherein the data stream and the control signals comprise a single pulse train such that a first plurality of intervals of the single pulse train are reserved for the data stream, and a second plurality of intervals of the single pulse train are reserved for the control signals.

22. The method according to claim 1, wherein the data stream and the control signals are transmitted to each of said display units, and at least some of the individual processing units are provided with a master clock correction arrangement.