High quality camera and video recording article with quotes from Feisal Mosleh

1. Image sensor enables higher quality images
and video recording in camera phones
Image sensor enables higher quality images and video recording in camera phones
EE Times
5/2/2006 10:00 PM EDT
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San Jose, Calif. — Avago Technologies unveils a one-quarter-inch optical format, 2-megapixel
CMOS image sensor with autofocus support that enables ultra-thin camera phones to record
high-definition videos (800 x 600 pixels) at 30 frames per second (fps) and produce digital still
camera-like images. It also incorporates for the first time Avago's multiplexed enhanced-
performance (EP) pixels that offer several benefits including improved sensitivity in low-light
conditions.
Housed in a SoC package that is comprised of the sensor, image processor and JPEG
compression engine, the ADCC-4050 is one of the few 2-megapixel sensors with 2.2 x 2.2
micron pixels that fits into the industry's smallest 8 x 8 x 5-mm low-profile camera modules. The
camera chip also combines Avago's EP pixel and array architecture and eight generation image-
pipe (I-Pipe) processing technology to achieve low image lag.
In addition, the imager's on-chip image processing and JPEG compression eliminates the need
for an additional companion chip while reducing system processing overhead, design
complexity, and time to market, said the company. The key improvement in the sensor array is

2. the reduced pixel pitch from 2.8 to 2.2 microns, said Sanjeev Chandrasekhar, product line
manager, for the Mobile Imaging Business at Avago Technologies.
To compensate for the smaller pixel, which impacts light capture, Avago developed some patent-
pending changes, namely the multiplexed EP pixel architecture to ensure higher sensitivity.
While the multiplexed EP pixels still use four transistors as in the earlier non-multiplexed
version it allows the fourth transistor to be shared across three to four pixels. This design change
translates into smaller die, increased fill factor, lower power consumption, less heat generation,
and ultimately, improved sensitivity and imaging.
"What we've done is to reduce the size of the pixel while at the same time increasing the fill
factor and almost retaining the same ability to capture light. This also reduces power
consumption and reduces the heat generated for lower noise," said Chandrasekhar.
ADCC-4050 Block Diagram
(Click on Image to Enlarge)
This design provides the best fill factor and sensitivity in low-light conditions, which is the most
important feature in camera phones, added Feisal Mosleh, director of worldwide marketing for
the Mobile Imaging Business at Avago Technologies.
The key benefits of the EP architecture include a reduction in dark current and noise, and the
removal of the lens shading effect to offer performance that rivals CCD sensors. The 3D pixel e-
field shaping is said to make each pixel ultra-light sensitive and the 8 x 8 pixel binning extends
pixel sensitivity. By comparison, competitors' image sensors offer 1 x 2 binning, said the
company.
The ADCC-4050 sensor is capable of 15 fps at full 1600 x 1200 pixel UXGA (ultra extended
graphics array) resolution, and 30 fps in 800 x 600 pixel SVGA mode. The image sensor
contains several digital still camera- and camcorder-like image-processing features, including the
eighth-generation JPEG with adaptive compression, which is said to deliver better quality
images, along with advanced features such as auto thumbnails for reduced image lag and lower
power use, fast reload to avoid missing shots, and spot metering with auto focus and exposure to
improve captured image quality.
The image sensor also incorporates two key features for camera module assemblers. These
include bad cluster correction that improves both picture quality (for users) and increases yield
(for manufacturers), and color variance correction to improve camera module yields and to
increase part-to-part camera module color consistency.

3. "The idea is to make sure there is very little color difference or performance variations from part
to part," said Chandrasekhar.
The 2-megapixel image sensor also features dual flash support, shutter lag amelioration, an
advanced auto illuminant detector, adaptive tone mapping for better contrast (more vivid colors),
and white balance and color adjustment. In addition, the image sensor automatically adapts to a
wide range of lighting conditions, from incandescent to fluorescent to sunlight and corrects
overexposed or underexposed images. The ADCC-4050 CMOS camera-on-a-chip is priced at
less than $5.00 in quantities of 1 million. Samples are available now with volume production
planned for third quarter 2006.
Avago Technologies, 1-800-235-0312, www.avagotech.com/imaging