What Is a Document Scanner?

A document scanner is an intriguing device. By simply laying an existing, physical document on a flatbed scanner (or passing it under a hand-held scanner), an entire document can be quickly and easily input into a computer, stored as a picture, or even read into a word processing program. This article will explore how this process works, types of scanners, benefits and use.

Function

In its most basic form, a document scanner is very much akin to a stationary digital camera. When a document is placed on the scanner (or passed under it for hand-held models), the scanner creates a digital image of the document much the same way a digital camera or photocopier works--by reflecting light off the document and recording the incoming reflections as digital images. These digital images are then fed to corresponding software applications on a connected computer, where the image is saved as a picture file (like a JPEG or Bitmap image), converted into an Acrobat-readable PDF file, or interpreted for use by a word processing application.

Types

Two major groups of scanners are commercially available today. The first group, the flatbed scanner, seems to be the most popular among home and small office users, as its familiar photocopier-like design allows for scanning of an entire document or page with only minimal interaction. The second group, more popular among commercial and industrial users, is a hand-held scanner which can be passed over portions of a document for precision scanning. In addition to these two major groups, other types of document scanners include pen scanners (shaped like an ink pen to provide maximum precision) and bar code scanners.

Features

Since the main function of a document scanner is to photograph and digitally interpret pages and documents, most of the scanner's features are made possible by its software. Currently, software exists to convert documents to photographs, PDF documents or word processing files. Some additional features which may be available, depending on the software, include the ability to read bar codes, the ability to interpret variations in color, the ability to sample handwriting and the reading of optical character recognition (OCR) data.

Benefits

When working with printed materials, such as old books or handwritten papers, a document scanner can considerably reduce the time and labor associated with inputting information into a computer. With optional OCR software, a scanner may even be able to convert some works into editable documents, bypassing a tremendous amount of manual data entry. In addition, a scanner is often used to preserve digital copies of old, sentimental, historic or valuable photographs and images. Finally, a portable scanner allows professionals to quickly and easily capture information, such as business cards, in an easy-to-organize digital form.

Considerations

While document scanning technology has come a long way since the clunky and awkward machines of the late 1980s, many features have not yet reached a level of complete reliability. Many consumer grade scanners, for example, still have difficulty interpreting OCR data, and may improperly read some characters into word processing applications. Photography purists also point out that scanned pictures often have slightly altered colors, especially when processed by lower priced, consumer grade scanners. Still, the document scanner continues to provide exceptional services, making digital copies of things that only exist in the physical realm.