Data symbol reader and method including data symbol position evaluation

摘要

A data symbol reading device has a casing which includes a hand grip and a head part. The casing includes signal processing circuits, a light source, an image sensing device, and an optical system. The optical system directs light reflected from a symbol reading area such that an image is formed on a light receiving surface of the image sensing device. An indication unit, comprised of five LEDs, is provided on an easily visible surface of the casing. If, in the reading process, it is determined that a data symbol is fully within the symbol reading area, a central LED is illuminated. However, if the data symbol is protruding outside the symbol reading area, one or more LEDs are illuminated to indicate the direction of protrusion.