Image Is Everything

Hank Hogan, Contributing Editor

In choosing image sensors, charge-coupled devices (CCDs) have long been the benchmark for image quality, offering significantly higher resolution than their competitors. But manufacturers are making great strides with complementary metal oxide semiconductor (CMOS) image sensors, and the choice is becoming much less black and white.
The choices made by Canon Computer Systems Inc. in Costa Mesa, Calif., illustrate the ongoing struggle between CCD and CMOS image sensors. Canon, which uses only CCDs in its consumer-oriented, $500-and-up Powershot digital cameras, does so primarily because of their superior image quality, according to John Lamb, product manager of digital cameras and scanners for the company. But Canon recently introduced two flatbed scanners for less than $100 that use CMOS-based contact image sensors. Bringing the sensor close to the scan surface eliminates the need for imaging optics, which cuts the overall price of the system without degrading image quality.