Scanners

Guide Note

Scanners analyze images, documents, or objects and convert them to digital files. Scanners read data through red-green-blue color (RGB) from the array, process it, and then send the data to the computer via a USB or input/output. Most scanners include infrared cleaning, which removes dust and scratches from film. In order for a computer to receive the scanned image, the scanner must be connected to the computer and have an application to retrieve the document from the scanner. Without either one of these, the scanner will not be able to work effectively.¹

Fast Facts

1. Four kinds of scanners: Flatbed Scanners, Sheet-fed Scanners, Handheld Scanners, and Drum Scanners
2. Drum scanners typically have the highest quality²
3. Quality depends on color depth and resolution
4. Scanner resolution is specified in DPI or dots per inch
5. For home use a 100 to 300 dpi is good for scanning photos or graphics¹
6. Native optical resolution is more important than enhanced resolution

The most common type of scanner is the versatile flatbed scanner, which can be placed on the desktop. The second type is a sheet-fed scanner, similar in size to the flatbed, but requires that the document be fed through the scanning mechanism as the scan head does not move. A third type is the handheld scanner which requires the user to move the scan mechanism. While this scanner is good for quick capturing, the image quality is not high. The fourth type of scanner is the drum scanner which is a professional grade scanner used for extremely high-quality images.³

• Epson
• Canon
• Hewlett-Packard
• Microtek
• Xerox
• Fujitsu
• Nikon