March 23, 1998 Design News
Technology bulletin
Late developments that shape
engineering
by Laurie Peach, Associate Editor
Are you seeing these colors yet?
The rose, a brilliant red. The sky, a purplish blue.
The sunset, a soft magenta. If you are seeing these
vivid colors, then you may be looking at the next generation
of video screens or computer displays. If you aren't,
that means the products aren't commercialized yet. But
they are possible, thanks to a new blue laser, developed
by Dr. E. Fred Schubert, professor of electrical and
computer engineering and a member of the faculty of
the Photonics Center at Boston University (Boston, MA).
In the February 1998, Issue 4, of Electronic Letters,
Schubert describes how he and Dean Stocker, a doctoral
candidate in physics, fabricated the world's first gallium
nitride (InGaN) double-heterostructure laser from tiny
pieces of polished sapphire under even smaller layers
of semiconducting crystal. The laser materials were
scored with a diamond and then "cleaved"--or
broken--along the scratch to produce smooth facets that
control the paths of the photons that make up the laser
beam. The blue laser may also expand the storage capacity
of today's digital video disks up to four times. For
more information, contact Joan Schwartz at (617) 353-4626,
e-mail: joschwar@bu.edu.
Getting a grip on battery assembly
Engineers at TBS Engineering presented re-searchers
at C4 Carbides (Cambridge, England) with a problem:
Design an efficient gripping system for a new type of
premium grade battery where lead cells are encased in
a glass fiber compound. The lead plates weigh up to
15 kg and cannot be out of alignment during the production
process or the battery will malfunction or fail. The
C4 Carbides solution: A process where tungsten grit
is metalurgically bonded with a nickel braze to almost
any steel alloy substrate, achieving a coefficient of
friction greater than 1.6. "Tungsten grit not only
gives us the grip we require, without deforming the
lead cells, but is also easy to keep clean as the lead
oxide--a dirty and sticky substance--doesn't adhere
to the surface," says Chris Barge, engineering
manager at TBS. Tungsten grit is a rising star among
precision gripping, grabbing, and clamping operations.
Other applications include a cable clamp for submarine
fiber optics and gripping clamps for the oil industry
to protect the stainless steel pipes used in the extrusion
of copper pipes. Phone Bob Nicolson at +44 (0) 1223-506406
or e-mail: c4@dial.pipex.com.
One chip does work of two
Ever ask the Great Pumpkin for a reconfigurable printed
circuit board (PCB) on a chip? Well, unlike Linus in
the pumpkin path, Motorola Semiconductor Products Sector
(Phoenix, AZ) developed a reconfigurable embedded system
process. Its new CORE+ technology, according to company
officials, is the world's first--combining standard,
diffused components, and field programmable gate arrays
(FPGA) on a single silicon substrate. "We've identified
a niche opportunity for this advanced product,"
says Ron Lipinski, director of operations. Motorola
took their in-house know how of microprocessors, microcontrollers,
and digital signal processors and merged this with their
FPGA ingenuity. "We can put whatever a customer
wants on silicon," Lipinski adds. Existing processes
require at least two chips. This not only means more
money, but you lose performance because electrons take
longer to move between them. The first product, expected
out by the third quarter of 1998, will be "the
industry's first hard diffused core." The MPACF250,
designed with Motorola's 68K-compatible Cold-Fire architecture,
combines 32-bit RISC with a memory-saving, variable-length
instruction set. The CORE+ family will be supported
by schematic capture, simulation, logic synthesis, compiler,
code debugging and in-circuit emulation tools from several
vendors. Contact Connie Schultejans at (602) 732-2852.
Go ahead, the water's fine
While drinking and driving may be hazardous to one's
health, drinking the water in France is not. Saur, a
water distribution company in France, installed electronic
sensors and high-performance monitoring equipment on
an aqueduct that supplies the drinking water for Disneyland
Paris. The devices measure physico-chemical and biological
data upstream of the water offtake and in the water-treatment
plant. Escherichia Coli (E. Coli) levels, measured every
two hrs, are used as harbingers of pathogens. Because
the bacteria acidifies on glucose media, the Disneyland
equipment holds 100 ml (3.4 oz) of water in a nutrient-rich
cell and automatically measures the variation in pH.
From this, it deduces the quantity of bacteria down
to one bacterium in 100 ml. Traditional analysis time
is 48 to 72 hrs. The new monitoring equipment provides
results within 11 hrs. Marketed by Ysebaert, the system
costs $34,000 to $38,000. Phone (312) 222-1237.
Filmless X-ray system on tap
X-rays without film. Fewer X-rays taken. Less radiation
exposure. Real-time digital images that can be stored
electronically or sent anywhere in the world via telecommunications
systems. Such will be the change in X-ray technology
with the large-scale, amorphous-silicon X-ray detectors
developed by GE Medical Systems (Milwaukee, WI). Conventional
X-ray film and chemicals are replaced with computer
images and a large-format X-ray detector. Measuring
up to 41 x 41 cm in the active area, GE says these are
the largest panels available anywhere. The immense format
and high pixel density eliminate the need for optical
image reduction. Each pixel delivers up to 16 bits of
dynamic-range (contrast) information. Officials at GE
predict this will revolutionize the way X-ray images
are acquired, analyzed and shared. The manufacture of
the detector starts with a pizza-box-size, glass-panel
substrate. Photolithographic techniques create photodiodes
by applying and patterning successive thin-film layers
of silicon, metals, and insulators. A final layer of
scintillator material, which converts X-ray photons
to visible light, is applied over the array. EG&G
(Santa Clara, CA) will have exclusive rights to manufacture
the panels, available for medical applications by late
1998 or early 1999. Phone (408) 565-0850.
Camera sniffs out deadly gases
Physicist Dr. Bijan Miremadi has developed a gas sensor
that could prevent disasters caused by dangerous gases
both at home and in the workplace. "To the best
of our knowledge, this is the only one of its kind in
existence," says Miremadi. Depending on the type
of sensor heads they use, most gas sensors currently
in the market are not selective to a particular gas.
His system is like a sniffing camera which can find
any gas and identify it. Miremadi developed two versions--a
handheld unit suitable for personal use or in the home,
and another unit that can be controlled by a computer
and monitor multi locations in office buildings, industrial
sites, and mines. The handheld version, now in the prototype
stage, can also be connected to a computer or operated
independently. Miremadi is currently looking for financing
to bring his products to market. The sensor was developed
with the support of SFU's university/industry liaison
office, in collaboration with Western Pacific Research
Corp., an SFU spin-off company.
Here comes porous silicon!
Although still three to five years away, computers
based on light signals instead of electrical signals
might put the Pentium chip to shame. Since 1992, scientists
knew that the holes in porous silicon contain microscopic
structures that emit light when electric current is
applied. But the untreated material was fragile. Oxygen
and water molecules in the air interact with the surface
and create a glass-like coating that disrupts its photoluminescence
properties. Jillian Buriak, assistant professor in Purdue's
Department of Chemistry, discovered a way to stabilize
the substrate's surface by coating the porous surface
of the silicon with Lewis acid, a solution which produces
a greasy coating. "Because most current technology
is based on silicon, it may be relatively easy to develop
the optical applications and combine them with current
technologies, as the manufacturing processes are already
in place," Buriak says. Porous silicon could easily
serve as a flat, millimeter-thick display area for computer
screens, as well as a basis for computers that operate
on light signals.
Gas up your fuel cell
Regular unleaded gasoline may soon power fuel-cell
vehicles. Arthur D. Little (ADL, Cambridge, MA), a technology-based
consulting firm, completed a five-year program sponsored
by the U.S. Department of Energy. Out of the study,
rose a reformer technology that converts gasoline and
other carbon sources to hydrogen on-board an automobile.
Fuel cells then convert the hydrogen to electricity
which powers the vehicle. Chrysler Corporation is working
on a model of a fuel cell car and hopes to demonstrate
a working vehicle with this technology in the next two
years. "Using the current fueling infrastructure
will shrink the time frame needed to achieve fuel cell-powered
family sedans," states Jeffrey Bentley, a director
in Technology and Product Development business. "Fuel
cells require hydrogen to operate and hydrogen is something
not sold at your neighborhood service station. This
breakthrough technology represents the first time that
gasoline can successfully operate fuel cells."
The reformer incorporates a fuel flexible design, enabling
a vehicle running on this technology to use a variety
of fuels.
One BIG crystal
Step right up and see the world's largest crystal!
It measures 52 cm (over 20 inches) across at the base
and weighs nearly 500 lbs. With a lot of loving care,
scientists at Livermore National Laboratory grew this
single crystal optical element using a rapid- growth
method. The fast growth method was pioneered in Russia
and perfected at Livermore over the past fe
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