Computer graphics processing and selective visual display system – Plural display systems
Reexamination Certificate
1999-01-15
2004-08-10
Razavi, Michael (Department: 2672)
Computer graphics processing and selective visual display system
Plural display systems
C345S001300
Reexamination Certificate
active
06774868
ABSTRACT:
TECHNICAL FIELD
The present invention relates to the field of displaying images and data. More specifically, the present invention relates to the field of large area displays.
BACKGROUND ART
Currently, there is a wide variety of devices and techniques utilized to visually display analog and/or digital signals containing moving images, data, and the like, thereby enabling people to view this information. Many of these display devices are very familiar to the general public. For instance, moving images and data are visually displayed on television sets, computer monitors, and arcade video games, to name a few. It should be appreciated that there are many different technologies which are utilized to implement these type of display devices. Some of these technologies include a cathode ray tube (CRT), a liquid crystal display (LCD), a laser based system, a reflective LCD, and a plasma display.
Furthermore, there are other existing techniques and technologies which are utilized to display moving images and data on a much larger scale than those mention above. For example, one technique for generating a large area display involves fabricating a “PowerWall” which is made-up of an array of projectors, each displaying a specific portion of the overall viewable image. Another technique for generating a large area display is similar to the PowerWall approach, except it involves the use of CRT monitors instead of projectors. Basically, a large area display is generated by utilizing an array of image projectors, each projecting a specific portion of the overall viewable image onto a desired surface. This technique is commonly referred to as “tiling”.
In order to more fully understand how a prior art large area display is generated utilizing tiled image projectors, a more detail description is presented. For simplicity, the generation of a single projected image by an image projector is initially described. It should be appreciated that each image projector generating a portion of the large area display operates in the same fashion.
FIG. 1A
is a diagram illustrating the manner in which a projected image
100
is typically generated by a prior art image projector (not shown), which is well known by those of ordinary skill in the art. Fundamentally, the image projector raster scans or “draws” the pixels of image
100
in a row, from left to right. Furthermore, the image projector raster scans the rows of pixels of image
100
from top to bottom. Once the bottom row of pixels of image
100
is raster scanned, the image projector returns to the upper left-hand corner to begin raster scanning the top row of pixels again. In this fashion, the image projector continually generates and updates image
100
by repeating the process described above.
Specifically, to generate projected image
100
, the image projector starts raster scanning pixel
102
, which is located in the upper left-hand corner of image
100
. The image projector proceeds to raster scan all of the pixels, from left to right, located in the top row of image
100
. Upon reaching pixel
104
, which is the right most pixel of the top row, the image projector stops raster scanning and proceeds to the left-hand edge of image
100
to begin raster scanning the next row of pixels. The image projector continues this process for each subsequent row of pixels until it reaches pixel
106
, located in the lower right-hand corner of image
100
. Upon raster scanning pixel
106
, the image projector stops raster scanning and returns to pixel
102
to repeat the raster scanning process described above. In this manner, the image projector continually generates and updates image
100
.
Now referring to
FIG. 1B
, which is a diagram illustrating a prior art manner of generating a typical large area display
120
by tiling projected images
100
,
122
,
124
, and
126
, which in combination result in a large viewable image. It should be appreciated that four image projectors (not shown) are utilized to generate projected images
100
,
122
,
124
, and
126
. Furthermore, it should be appreciated that each image projector generates one of projected images
100
,
122
,
124
, and
126
. It should be further appreciated that projected images
122
-
126
are each generated in the same manner as projected image
100
, as described above. Specifically, at time equal to zero, all four image projectors simultaneously begin raster scanning, from left to right, the top rows of pixels of projected images
100
,
122
,
124
, and
126
. Furthermore, the image projectors raster scan the rows of pixels of images
100
,
122
,
124
, and
126
from top to bottom. Once the bottom rows of pixels of images
100
,
122
,
124
, and
126
are raster scanned, the image projectors repeat this process in order to continuously update and generate large area display
120
.
There are disadvantages associated with the prior art technique of tiling multiple image projectors to generate a large area display, as described above. One of the main disadvantages is that it produces images exhibiting visual defects or anomalies which are particularly evident along the horizontal seams located between the projected images (e.g.,
100
,
122
,
124
, and
126
). Furthermore, these visual anomalies are more pronounced when certain images (e.g., visual simulation) are being displayed. The occurrence of these visual anomalies are attributed to the fact that the pixels near the horizontal seams are temporally out of phase.
For example, as the lower rows of pixels of images
100
and
122
are raster scanned displaying the end of a frame of data, the upper rows of pixels of images
124
and
126
are raster scanned around the same time displaying the beginning of a subsequent frame of data. As such, two different frames of data coexist near the horizontal seam of images
100
,
122
,
124
and
126
. Therefore, the pixels near the horizontal seam of images
100
,
122
,
124
, and
126
are temporally out of phase. As such, an image appears to “tear” as it is displayed moving horizontally across large area display
120
along the horizontal seam between images
100
,
122
,
124
, and
126
because the human eye integrates the image generated by pixels that are illuminated at approximately the same time (see FIG.
1
C). Pixel
106
is illuminated near the end of each frame, whereas pixel
128
is illuminated near the start of each frame. As such, it is apparent in
FIG. 1C
that the image information for frame
0
for pixel
106
will get integrated with frame
1
information for pixel
128
. This means that an object that is moving horizontally along the horizontal seam will have some pixels from one frame and other pixels sampled from the subsequent frame. The motion of the object will tear the overall image. Note that the pixel is really only bright when the scan beam hits the pixel, then the phosphor's light emission decays fairly rapidly. Much of the image retention is in the workings of the human eye. In other words, psycho-visual anomalies are generated by this prior art tiling technique since the pixels near the horizontal seams are temporally out of phase.
Accordingly, a need exists for a method and system for tiling multiple image projectors to generate a large area display of moving images and data which does not exhibit visual defects or anomalies.
DISCLOSURE OF THE INVENTION
The present invention provides a method and system for tiling multiple image projectors to generate a large area display of moving images and data which is free of visual defects or anomalies. Therefore, the present invention is able to produce large area displays exhibiting more realistic and lifelike images thereby improving the viewing experience of the viewer.
Specifically, one embodiment of the present invention includes a system for generating a large area display of moving data. The system comprises a display image generator for rendering pixels of an image to be displayed as the large area display. Furthermore, a plurality of tiled image projectors are coupled to the display image generator
Harrison Chante′
Microsoft Corporation
Razavi Michael
Woodcock & Washburn LLP
LandOfFree
Method for tiling multiple displays to generate a large area... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for tiling multiple displays to generate a large area..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for tiling multiple displays to generate a large area... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3295526