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According
to an article in EETimes the race is on to merge image processing and
CMOS sensor into one device, "Some companies are going for an extremely
high-quality, high-price CMOS sensor market, while others are going for
lower-priced products. Vendors need to differentiate, but it's getting
more difficult for them to define their own niche," In-Stat's O'Rourke
said.
EETimes
article:
Race is on to merge image processing, CMOS sensor
By Junko Yoshida, EE Times
SAN MATEO, Calif. The competition in CMOS image sensors has turned
ferocious, pitting established giants such as Agilent Technologies Inc.
against such smaller upstarts as IC Media Corp.
The combatants are marshaling integrated solutions that will pair front-end
sensors with back-end imaging processors in a bid to lower the cost, size
and power consumption of digital imaging systems.
Agilent (Palo Alto, Calif.), the largest CMOS image-sensor supplier in
the industry, is ready to introduce a family of image processor chips
that is designed to work well with its own CMOS image sensors. The rollout
marks Agilent's first step in a self-transformation from a "pure
sensor play to a system-level digital-imaging solution provider,"
said Jason Hartlove, business unit manager at Agilent's Imaging Electronics
Division.
Meanwhile, a little-known startup called IC Media (San Jose, Calif.)
is introducing its first CMOS VGA image sensor and setting a new low price
point for PC cameras. At a time when most CMOS VGA sensors are produced
in a 0.5-micron process, IC Media is mass-producing its CMOS sensor using
United Microelectronics Corp.'s 0.35-micron process, said Jim Li, executive
vice president of IC Media. The finer geometry means a lower cost and
allows camera OEMs to use a quarter-inch optical system rather than the
current one-third-inch optics with the image sensor. "That translates
into a more compact design and cost savings at the system level,"
Li said.
So far, Agilent is the only other vendor that has shifted to 0.35-micron
geometry; the company is announcing two CMOS image sensors Oct. 30 in
CIF and VGA resolutions.
Down the road
Many CMOS sensor companies see the mobile/cell phone market as the key
to future business and are racing to find partners or develop their own
technologies internally. Their goal is to offer both CMOS image sensors
and image-processing solutions now, along with a road map to integrate
both onto a single chip. "Agilent's move definitely sends a warning
signal to the market, that sensor vendors need to get more involved in
the back-end image-processing business," said Brian O'Rourke, senior
analyst at Cahner's In-Stat Group.
Such a trend is already evident. STMicroelectronics, for one, took the
first step by acquiring VLSI Vision Ltd., a well-known CMOS image-sensor
company, in early 1999. Through the acquisition of Sierra Imaging Inc.
earlier this year, Conexant Systems Inc. also positioned itself to offer
digital camera manufacturers complete camera solutions combining
Sierra's back-end digital-image processors and image-management software
with Conexant's front-end CMOS image sensors.
Similarly, Zoran Corp. earlier this year acquired PixelCam Inc., a privately
held maker of megapixel CMOS image sensors. Zoran's ambition is to become
a one-stop shop for OEMs to source both image sensor and image compression
solutions.
Not every company is following the acquisition and merger route, however.
Photobit Corp., a CMOS image-sensor technology innovator, is developing
its own fully digital color processor. Photobit designed the processor
to do color-processing functions including white balance, color correction
and others, but with no standard image compression, said Michael Kaplinsky,
the Photobit business unit manager responsible for mobile applications.
Such a fully digital color processor will be integrated with Photobit's
own CMOS sensor on a single "camera-on-a-chip" for mobile phone
applications, he said.
Image sensor/image processor integration is essential for cell-phone
and camera applications, due to system requirements for smaller size and
low power consumption, Kaplinsky said. In the first quarter of 2001, Photobit
will roll out a tiny camera-on-a-chip that operates at 2.7 volts with
power consumption of less than 50 milliwatts, he said.
For now, however, the volume market for CMOS image sensors centers on
PC cameras and digital still cameras. According to IDC analyst Ron Glaz,
6 million units of CMOS image sensors are expected to ship in the PC camera
market in 2000 and 5 million for the digital still camera market.
Like Photobit, Agilent, too, is moving into the image processor market
using internal resources. The company is introducing two image-processing
chips HDCP-2000 for USB-based PC cameras and HDCP-2010 for handheld
computers, cell phones and notebook computers. Designed for VGA- and CIF-resolution
cameras, both chips provide complete sensor control, including autoexposure
and auto white-balance functions as well as true JPEG compression with
programmable quantization tables.
Some PC camera IC solutions available on the market today offer minor
compression on the chip, which allows the raw imaging data that a sensor
captures to be compressed enough to travel over a Universal Serial Bus.
In such a design, the rest of the image-processing functions, such as
color correction, white balance and full image compression, are carried
out on a PC.
Agilent engineers nixed that approach, Hartlove said, "because you
lose the quality of data through such a minor compression, which could
also introduce artifacts, and is further enhanced in the image processing
done on the PC later."
Agilent's HDCP-2000, priced at $7.95 in 10,000-unit orders, features
a USB interface to communicate imaging data over that bus, while the HDCP-2010
offers fully processed image output in either direct JPEG or YUV formats
for parallel or serial output. The HDCP-2010, also priced at $7.95 in
10,000-unit orders, is well-suited to mobile applications because it comes
in a much smaller 48-pin micro-BGA package and consumes less than 100
mW.
Both of the Agilent imaging processors feature a sensor interface peculiar
to the Hewlett-Packard HDCS family of CMOS image sensors. "Our image
processors fully take advantage of the characteristics of our own image
sensors and offer a complete image-processing pipeline," Hartlove
said.
Photobit's Kaplinsky noted that matching image processors to specific
CMOS sensors brings advantages beyond the ability to offer a one-stop
shop for digital imaging solutions. "You could design image processors
to reproduce the best possible results, by leveraging the intimate knowledge
of your own sensors' dynamic range and spectrum characteristics,"
he said.
In addition to its two image-processing chips, Agilent is also launching
HDCP-3200, a complete digital-image processor designed for a full-featured
digital still camera. A Motorola Coldfire 32-bit core running at 144 MHz
and embedded on-chip provides flexibility for adding new features and
customizing a design. The chip offers a high-performance hardware image
pipeline and JPEG codec, the company said.
"All the numeric-intensive tasks are done in hardware, rather than
running software on Coldfire," Hartlove said, "so that the chip
consumes a lot less power, and it runs much faster for consecutive shooting."
The new HDCP-3200 is based on the HDCP-3000, which was originally used
in HP-designed digital cameras. The Agilent image processor, designed
for midrange to low-end digital still cameras, can be used with any type
of sensors CCD or CMOS. Available now, it is priced at $17 in lots
of 10,000.
Meanwhile, the CMOS image-sensor market grows increasingly crowded. "Some
companies are going for an extremely high-quality, high-price CMOS sensor
market, while others are going for lower-priced products. Vendors need
to differentiate, but it's getting more difficult for them to define their
own niche," In-Stat's O'Rourke said.
IC Media's first commercial product, ICM105A, is a CMOS image sensor
that incorporates a 640 x 480-sensor array that can capture still or full-motion
video at up to 30 frames/second and convert the images to digital data.
It includes a 9-bit analog-to-digital converter that performs correlated
double sampling to improve image quality.
Ben Wu, president and chief executive officer at IC Media, said the company
achieved a couple of things by moving to a 0.35-micron process from 0.5-micron
CMOS, where availability is increasingly tight these days. "We've
not only secured an ample supply for our customers, but also lowered the
cost," Wu said. The ICM105A uses 6 x 6-µm digital sensors,
which in effect offer better quality than many 8 x 8-µm sensors
based on a 0.5-micron process, claimed executive vice president Li. "It
turns out that the 0.35-micron process offers more accurate, better alignment."
Not to be outdone, Agilent is launching two new CMOS image sensors of
its own: HDCS-2020 for VGA and HDCS-1020 for CIF resolution. Both are
available in volume now, the company said. The VGA version integrates
a 10-bit A/D and offers 15 frames/s, while the CIF device provides an
8-bit A/D and handles 30 frames/s. Both sensors are based on a high-sensitivity,
low-noise design, making it possible to capture images in a wide variety
of lighting conditions, Hartlove said.
Thanks to a switch to a 0.35-micron process, the Agilent CMOS image sensors
use a 7.4-micron pixel pitch. "We maintained the high-performance
image quality of our sensors while shrinking the die size by implementing
dark-current optimization," he added.
Compared to Agilent, IC Media, the newcomer, is pricing its CMOS image
sensor much more aggressively. IC Media's CMOS VGA image sensor is priced
at $7.35 in 10,000-unit orders, while Agilent's CMOS VGA sensor is offered
at $12.25 and its CMOS CIF sensor at $7.95.
Pointing to market demand, Wu said IC Media aims to offer solutions that
integrate its CMOS sensor with internally developed image-processing blocks.
He called the company's ICM512D a system-on-chip that integrates a CIF-resolution
CMOS sensor, color processing and NTSC encoder, with a TV output. Built
in a 0.5-micron process, it is priced at $10.50 in lots of 10,000.
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