Google Answers Logo
View Question
Q: Surface Conduction Electron Emitting Display (SED) ( Answered,   0 Comments )
Subject: Surface Conduction Electron Emitting Display (SED)
Category: Science > Technology
Asked by: alpheus-ga
List Price: $200.00
Posted: 26 May 2005 10:17 PDT
Expires: 25 Jun 2005 10:17 PDT
Question ID: 525928
Tell us everything you know about this process, what Cannon and
Toshiba are doing with the process and how dramatically different will
the products be that have SED.
Subject: Re: Surface Conduction Electron Emitting Display (SED)
Answered By: websearcher-ga on 26 May 2005 15:05 PDT
Hello alpheus:

Thank you for the challenging question.

There is not a large amount of easily-accessible information available
about Surface-conduction Electron-emitter Display (SED) technology at
this time. This is due to the fact that Canon (who invented it) and
Toshiba (who is partnering with Canon on this technology) are planning
to release the first models of TVs using SED later this year. They
likely want to keep the technical details rather buried at the moment.

I have, however, found some interesting information available over the
Web. I have organized what I've found for you below.

Basic Facts and Definitions

surface-conduction electron-emitter display
Quote: "The surface-conduction electron-emitter display (SED) is a
flat-panel, high-resolution display currently under development by
Canon and Toshiba. It is expected to gain wide acceptance for use in
television receivers. Some SEDs have a diagonal measurement exceeding
one meter (approximately 40 inches), yet they consume only about 50
percent of the power of cathode-ray tube (CRT) displays, and 33
percent of the power of plasma displays having a comparable diagonal
The SED consists of an array of electron emitters and a layer of
phosphor, separated by a small space from which all the air has been
evacuated. Each electron emitter represents one pixel (picture
element). The SED requires no electron-beam focusing, and operates at
a much lower voltage than a CRT. The brightness and contrast compare
favorably with high-end CRTs. Prototype electron emitters have been
developed with diameters of a few nanometers (billionths of a meter)."
Note: Obviously, that estimated 2002 release date was not achieved!

Information from the Manufacturers

The following Web page is the most detailed, consumer-level
description of the technology available from Canon/Toshiba:

Flat-Panel SED
Quote: "The advent of the high-definition TV and the broadband network
era has led to demand for larger screens and higher image quality.
However, enlarging CRT (cathode ray tube) screens, today's most common
display, entails making the units significantly heavier and deeper.
A major challenge display manufacturers are facing has been how to
develop a new kind of display offering the same picture quality as a
CRT in a slim yet large unit. Canon's SED (Surface-conduction
Electron-emitter Display) has successfully met this challenge."
Note: Read the whole article - there are some interesting diagrams and
technical details.

Canon, Toshiba to create joint venture for next-generation flat-screen SED panels
Quote: "TOKYO, September 14, 2004 - Canon Inc. (President & CEO: Fujio
Mitarai) and Toshiba Corporation (President & CEO: Tadashi Okamura)
announced today that the two companies have agreed to establish a
joint venture in October 2004 for the development, production and
marketing of next-generation flat-screen SED (Surface-conduction
Electron-emitter Display) panels."

Comparisons to Other Display Technologies

The three major technologies is displays right now are Cathode Ray
Tube (CRT), Plasma Display Panels (PDP), and Liquid Crystal Displays
(LCD). Here are some comparisons of the new SED technology to those
existing technologies.

Flat Panel Displays - Beyond Plasma
Quote: "The visual advantages of SEDs are as for CRT displays, great
color, deep black levels and quick motion response. These advantages,
combined with the slim form factor, low cost and small power
requirement should make for a real winner.
A unit shown by Toshiba at a Japanese trade show in April of 2005 even
had it?s contrast ratio up to an incredible 100,000 to 1 by
significantly reducing black luminance. Even if the specs were a bit
inflated this would still amount to a fantastic contrast ratio, on the
order of 5 times that of a traditional CRT."

SED Technology for Large Displays on the Horizon
Quote: "According to Ramirez, "This technology is better than plasma
or LCDs for large screens," in reference to their SED technology. 
This statement is backed up by an informative SED technology primer
that has been available at Canon's website for some time now which
states that SEDs have "energy consumption that is roughly one-half
that of a large-screen CRT and about one-third that of a plasma
display panel."
Those curious in the details of the technology would do well to peruse
the primer, but here are a few highlights:
* same picture quality as a CRT
* wall-mounted large-screen TV displays that are only several centimeters thick
* energy consumption that is roughly one-half that of a large-screen
CRT and about one-third that of a plasma display panel"

More Photos of SED (surface-conduction electron-emitter display) TVs
Quote: "Notice the sharpness and vibrant color in the second photo
above.  Also, the last photo above appears to show the SED display
(center) side-by-side with other display technologies (probably plasma
and LCD).  Notice the starck (sic) contrast in the quality of the
One important note is that while SEDs are an extension of the CRT
concept (with phospors (sic) being charged to emit light), this does
not mean that SEDs (or CRTs for that matter) are inferior in display
quality to newer technologies like plasma and LCD.  Rather, CRT
displays still have the highest quality picture of any display type,
which is evident if you note the justifiably higher price of CRT-based
HDTVs or monitors versus LCD and plasma HDTVs or monitors of the same

SED Panel Contrast Ratio Boosted to 100,000:1
Quote: "At the Display 2005 event held in Tokyo on April 20, 2005, SED
(Surface-conduction Electron-emitter Display) Inc., a joint venture
formed by Canon Inc. and Toshiba Corp., unveiled a SED panel with full
On/Off contrast ratio boosted to approximately 100,000:1. The
company's first SED panel revealed at CEATEC JAPAN 2004 only achieved
a contrast ratio of 8,600:1.
The key factor behind the sharp rise in contrast ratio is a broad
reduction in black luminance. Black luminance has been reduced to
0.003 cd/m2, from the previous prototypes' 0.04 cd/m2. "We have
achieved the sharp cut in black luminance by improving the
electron-emitting source property,""

When to Expect to See SEDs

Cover Story: SED: Rising Star in TV Market?
Quote: "Canon and Toshiba Corp of Japan announced that they will begin
small-lot production of surface-conduction electron-emitter display
(SED) panels in August 2005, shifting to full-scale production in
2007. According to the business plan released by their joint-venture
firm, SED Inc of Japan, which will handle development, manufacture and
sales, the 2010 shipment volume will have reached 3 million panels
with a revenue of 200 billion (Fig 1). The average per-panel shipment
value will be about 67,000. And considering that its budget shows the
firm making a profit that year, the per-panel cost must be even
Note: There are three very good diagrams in this article. Click on them to enlarge.

Making Sense of It All
Quote: "No definite price or release date was available, but
representatives from Toshiba and Canon suggested that the first such
product will be a 50-inch 1920x1080 display shipping sometime in late
2005 or early 2006."
Note: Article from January 16, 2005.

SED Technology for Large Displays on the Horizon
Legal Troubles?
Quote: "According to CNET News, Canon CEO Fujio Mitarai stated in
April that the company's first SED televisions are expected to debut
by 2005.  The recent news of an upcoming announcement in October and a
patent purchase in related display technology point to the fact that
the two companies should live up to the CEO's timeline."

The Past, Present and Future of SEDs
Quote: "It seems like I've been following the progress of SED
(surface-conduction electron-emitter display) technology forever now
even though it's only been a year or two, but, as news sources have
been reporting (especially with the technology demonstrations for the
first time in the U.S. at CES), Canon and Toshiba's joint venture, SED
Inc. of Japan - formed in the late 1990s, will be producing SEDs in
August of this year."
Note: Article from January 11, 2005

Flat Panel Displays - Beyond Plasma
Quote: "Toshiba has indicated they will move to this technology for
all displays over 40 inches by 2006."

Manufacturing Information

Cover Story: SED: Rising Star in TV Market?
Quote: "Manufacturing Method
Given that the ratio of materials expense within the total cost is
low, the key target for Canon and Toshiba in SED manufacturing will be
keeping fixed expenses down. There are basically three approaches they
can take: use equipment with the small number of manufacturing
processes, reduce the cost of the equipment itself, or boost
production scale to accelerate depreciation. Another possibility is to
increase the size of the group manufacturing SED panels by licensing.
These approaches make it possible to fully enjoy the benefits of
in-house development. Canon and Toshiba will be making about half of
the panel manufacturing equipment themselves, because general-purpose
equipment designed to handle the special processes needed to make SED
panels just doesn't exist. Each firm has its own equipment technology
expertise, such as Canon's knowledge of equipment for exposure and
precision fabrication, and Toshiba's experience in CRT manufacturing
and semiconductor manufacturing equipment. The manufacturing equipment
used for SED panels will make use of technologies from both firms."

Legal Troubles?

Canon has a lawsuit pending against them over their SED technology
that could delay things.

Flat Panel Displays - Beyond Plasma
Quote: "One fly in the SED ointment however. On April 21st, 2005 US
firm Nano-Proprietary has filed a suit against Canon in the U.S.
District Court of the Western District of Texas, alleging that the
surface (SED) televisions that Canon plans to release violates a
licensing agreement signed 5 years ago between the Japanese giant and

Nano-Proprietary Files Declaratory Judgment Action Against Canon
Quote: "Nano-Proprietary, Inc. (OTC: NNPP) (BULLETIN BOARD: NNPP)
announced today that it has filed suit against Canon, Inc. (NYSE: CAJ)
in U.S. District Court for the Western District of Texas, Austin
Division. Nano-Proprietary is seeking a declaratory judgment that new
SED color television products, scheduled to be manufactured by Canon
and/or Toshiba beginning in August 2005, are not covered under a 1999
patent license agreement between Canon and Nano-Proprietary.
Nano-Proprietary alleges that Canon is improperly using
Nano-Proprietary's patented technology to produce surface conductor
electron emitter display screens (SED) for a new generation of flat
screen color televisions."

Deeper Technical Information

I went to the United States Patent and Trademark Office (USPTO) to see
what patents Canon currently had filed with respect to the SED

I used their advanced search facility:

Full-Text Database Manual Search

and entered the following Query:

"surface-conduction" AND display AND emitter AND an/canon

The resulting list contained 52 patents, all assigned to Canon:

Search Result

Of course, you'd have to be a pretty sharp electrical (display)
engineer to understand 1/10 of what's in these patents, but I think
some general knowledge can be gleaned by reading them.

Search Strategy (on Google):
* "Surface Conduction Electron Emitting Display"
* "SED" display
* "SED" display
* SED display patent
* canon
* toshiba
* uspto

I hope this information is of use to you. Please let me know if you
need any clarification of my answer before you rate it.

There are no comments at this time.

Important Disclaimer: Answers and comments provided on Google Answers are general information, and are not intended to substitute for informed professional medical, psychiatric, psychological, tax, legal, investment, accounting, or other professional advice. Google does not endorse, and expressly disclaims liability for any product, manufacturer, distributor, service or service provider mentioned or any opinion expressed in answers or comments. Please read carefully the Google Answers Terms of Service.

If you feel that you have found inappropriate content, please let us know by emailing us at with the question ID listed above. Thank you.
Search Google Answers for
Google Answers  

Google Home - Answers FAQ - Terms of Service - Privacy Policy