TV Giants are Flatliners in Stereo 3-D Patents
The world's top television makers appear to hold no significant patents in stereoscopic 3-D despite the fact that some of the largest Hollywood studios want to drive the concept of 3DTV into the market. LG, Matsushita, Samsung, Sony and Toshiba currently have no significant patents on stereo 3-D, according to an initial patent search by EE Times.
Hollywood studios want to help set a standard for 3DTV so they can sell home versions of the increasing number of 3-D movies they are creating for the cinema. Some observers say stereo 3-D could be the next big thing in television beyond today's high definition flat panel systems. Others say the technology is far from ready for prime time.
Some 184 patents come up on a search of the U.S. patent office Web site for stereoscopic 3-D. About half those patents apply to product concepts such as 3DTV, with most of the rest related to a variety of topics including 3-D printing.
The earliest of the patents in that search was granted back in March 1988 to engineers from the apparently defunct 3-D Video Corp. (Hollywood). Patent number 4,734,756 describes a stereoscopic television system that is comprehensive in scope but dated in its implementation. The patent details a whole stereo 3-D chain from camera to disk and tape recording, encoding for transmission and display. However it specifies CRT displays and color anaglyph viewing--both of which are now widely seen as outmoded.
Sharp Electronics Corp. is the king of stereo 3-D intellectual property with at least 11 stereo 3-D patents granted since 1995. The company's patents have received a whopping 99 citations in other filings. A couple of Sharp's patents (number 7,079,174 granted in 2006 and 6,831,624 from 2004) appear broadly applicable to a wide variety LCD displays that could show 2-D and stereo 3-D images. The company's most recent patent in the area (number 7,250,710, granted in 2007) relates to stereo 3-D on an OLED display. Six other patents granted between 1995 and 2003 reference autostereoscopic technology, a Holy Grail of the field, because it does not require glasses to resolve to parallel images. Use of a spatial light modulator is key in at least five of the patents. Modulators and polarizing screens are sometimes used to resolve images from two displays in a way that generates a stereo 3-D image.
The search showed no stereo 3-D patents for TV giants including LG, Mitsubishi, Samsung and Sony.
Philips has one patent (number 6,831,950, granted in 2004) on an encoding scheme which it relates in part to use for stereo 3-D video. Toshiba had three patents, but they were related specifically to computer tomography imaging systems. Matsushita had two but only one was related to stereo 3-D, and not directly to 3DTV.
Interest in stereo 3-D seems to be on the rise. In the last two years, the U.S. patent office has seen a steady flow of patent applications on the topic, sometimes multiple filings a day. The office received about 40 applications on stereo 3-D in 2007 alone. Many of the filings did not cite a company but did come from individuals or teams from Korea and Japan.
Korea's TV giants are playing catch up in stereo 3-D. Samsung has filed at least seven and LG has submitted at least three patent applications in the area in less than two years. Samsung's applications include one on a switchable 2-D/3-D display, another on a compression technology for stereo 3-D and two on autostereoscopic technology.
There's still time for the big players to catch up. One patent expert said patents only become really valuable when they apply to shipping products. Although Samsung and LG are experimenting with early 3DTV systems, most observers believe it could take three to five years or longer before the industry sets standards for 3DTVs geared for the mainstream.
"We haven't heard anyone talking about [3DTV patents] yet," said Joe Chernesky, president of IPotential (San Mateo, Calif.), a patent consulting and brokerage firm. "We typically see activity when there are products on the market that can be considered as infringing," he added. Activity in patents related to networked content and video streaming, especially to handheld devices have been huge, recently with many of the patent filings starting around 2000, he said.
A smattering of top electronic companies have one or two interesting patents in stereo 3-D including Advanced Micro Devices, Intel, Microsoft, NEC and Nokia.
Microsoft was granted in January patent number 7,319,720 on stereoscopic video. It primarily describes a plug-and-play method of tailoring stereo 3-D data to the needs of a specific display, a major concern for developers at a time of a variety of emerging display technologies. The patent also touches on issues including data formats, compression schemes and capture techniques for stereo 3-D.
Nokia patented an approach to generating 2-D or stereo 3-D images from a single data stream. The cellphone giant snagged patent number 7,283,665 in October 2007.
Many of the stakeholders in stereo 3-D patents are small startups and individual inventors. For example, James Fergason, a veteran inventor considered by many the father of the LCD, holds five stereo 3-D patents granted in 2008 as part of a so-called StereoMirror portfolio he licenses as part of his company, Fergason Patent Properties LLC. The patents basically describe a system that uses two LCD displays mounted one above the other. The screens display the left and right images of a stereo 3-D image that is created when a polarizing filter is inserted between them. "It's not the cheapest [way to implement stereo 3-D], though it's not prohibitive and could be considered for high-end gamers," said Fergason. "The approach is set up so you don't lose any resolution, and the images can be viewed by multiple people simultaneously," he added.
Planar Systems (Beaverton, Oregon) licensed the technology which is being used in systems by military and security analysts to review 3-D versions of satellite imagery. Fergason's patents also describe a way to convert computer tomography data into stereo 3-D images.
"We are very bullish on [the patents] because it looks like they offer capabilities others don't have, but we stopped short of promoting them for gaming," Fergason said.
Indeed, Chuck McLaughlin a veteran display analyst who now helps Fergason market his patents, says he is skeptical about using stereo 3-D in consumer applications. Stereo 3-D is "still a somewhat limited proposition in the professional market and in the consumer market it's risky," McLaughlin said. "I'm not so sure [3DTV] will happen as some people hope it will," he added. "In real life we focus and converge on the same 3-D space, but in electronics the trick is we focus on one spot and converge on another," he said. "That can make people feel uncomfortable, but nobody really wants to talk about that fact."
Nausea was not uncommon with color anaglyph glasses and analog projectors used in 3-D movies during its first big fad in the 1950's. The latest polarizing glasses and digital projection techniques have significantly reduced the problem, though it has not been eliminated, experts say.
Two small startups hold a handful of interesting 3-D patents.
Dynamic Digital Depth (DDD; Santa Monica, Calif.) has at least five patents acquired over as many years, primarily on encoding techniques. The company offers a suite of software for converting 2-D images to stereo 3-D as well as a set-top box that can be used to convert TV content to 3-D for viewing with polarized glasses. DDD licensed some of its software to Sharp in September 2003. Sharp used the code in its Actius RD3D notebook, a laptop sporting a switchable 2-D/3-D display. Reviewers generally panned the 3-D capability as a novelty with limited content.
Another startup Vrex (Hawthorne, NY) has at least four 3-D patents including number 7,180,554 granted in 2007 for use with a digital light processing display. The company claims its founder, Sadeg Faris, has more than twenty patents and applications. Vrex primarily focuses on professional markets for its line of projection systems, converter boxes and specialty glasses for use with monitors and notebooks.
By Rick Merritt, EE Times
