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Camera surveillance is one of the fastest growing segments in the physical security arena. But the real story involves a potential paradigm shift from charge coupled device (CCD) imaging technology to complementary metal oxide semiconductor (CMOS).
As you probably already know, the video surveillance market has been dominated for nearly two decades by CCD imagers. CMOS technology is not new, however, as CMOS technology developed right alongside that of CCD in the 1970s. Because of limitations in CMOS technology imposed due to manufacturing constraints, CCDs became the de facto standard in digital camera production.
“The camera industry has grown accustomed to using CCD imagers for more than 20 years and for a good reason,” said Jason Wang, senior product marketing manager at OmniVision, Sunnyvale, Calif. “CMOS experienced a setback at that time because of limitations in the manufacturing process. But, most of the issues surrounding CMOS use have been remedied.”
CMOS improvements more attractive than CCD
In the past, one of the primary problems with CMOS technology involved light sensitivity. CCD imagers traditionally provide better images with less light, and this is the fundamental reason why CCD technology has ruled the market for more than 25 years. However, improvements in CMOS manufacturing have narrowed this advantage.
There are several other improvements in CMOS imagers that also have caught the eye of camera manufacturers. For example, CMOS chips draw less power than their CCD cousins, and this equates to the use of smaller power supplies and a longer effective life expectancy, all of which means lower operating costs. CMOS chips also take up less realty than CCD, which means CMOS-based cameras generally have a smaller footprint.
CMOS imaging technology also lends itself more readily to increased levels of in-chip processing. This essentially is because CMOS chips are made using the same type of chip as other common electronic devices, such as cellular telephones.
“If you look at the total production of all integrated circuits today, 99 percent are on CMOS wafers,” said John Monti, vice president of sales, Pixim, Mountain View, Calif. “There’s a massive infrastructure already in place that uses CMOS technology, and this is the reason that Pixim partnered with one of the largest CMOS chip manufacturers in the world.”
Because CMOS camera imagers are built on the same platform as ordinary processing chips, electronic manufacturers are more apt to integrate CMOS imagers into other systems. A good example of that are camera phones offered by many cellular service providers.
“Low power consumption and a high level of integration on a single chip translates into a smaller package. This means CMOS will be used in more systems/products, which in turn will bring the cost down,” said OmniVision’s Wang.
In a subsequent issue of Security + Life Safety Systems, we will discuss how CMOS-based cameras already have changed the face of security and how they are likely to affect an even larger portion of the market in the years to come.
COLOMBO is a 32-year veteran in the security and life-safety markets. He is currently director with FireNetOnline.