says. "We aren't able to announce [a color keyboard scanner] until next year because the components are just too expensive," he says.
The main component
used in monochrome keyboard scanners, or in future color versions, is called a contact image sensor (CIS). Keyboard scanners do not use the more mature and inexpensive light-sensing device used in most flatbed, sheetfed, and hand-held scanners -- a charge-coupled device (CCD) -- which is a solid-state element that senses light levels. CCDs determine the optical resolution in most scanners.
Monochrome CISes are used in Visioneer's keyboard scanner. CISes are packaged differently than CCDs. For example, flatbeds require many separate elements: CCDs, mirrors, lenses, etc. CISes come in modules: They include the lens, light source, and other elements in the same package.
Monochrome CISes are mature, but the color versions are not. Color CISes are also expensive and limited in terms of suppliers. Canon, Dyna Image, and a few others sell color CISes with 300-dpi resolution, but the price is a major drawback: These components sell for about $50 per unit, as compared to only $12 to $13 for a color CCD with si
milar specs.
Prices for color CISes are not expected to drop rapidly in the near future. "Color CIS devices will not make good solutions for scanners. The quality of CISes is not as good as CCDs, and they are expensive," says Abel Wang, industry analyst with the Market Intelligence Center in Taiwan.
Nevertheless, Spot is trying to incorporate a color CIS in a keyboard scanner. "We must use a color CIS because they are light and compact," Hwang says.
Coming: The Color Keyboard Scanner
