Abstract: An interface between a two-dimensional bar code scanner and a host digital decoder is provided through a 15-pin electronic connector, which transfers to the decoder an actuating signal either from a scanner trigger switch or from an external device. In response, the digital decoder provides the scanner with operating power. The scanner generates and relays a bar code signal and a scanning direction signal back to the digital decoder, which uses these signals to identify a bar code being scanned as a one-dimensional or two-dimensional code. If the bar code is determined to be a two-dimensional code, upon detection of laser pattern alignment with the label the digital decoder sends a scanning control signal to the scanner to control a laser pattern generated by the scanner.

Abstract: An electro-optical scanning device reads indicia having parts of different light reflectivity, including bar codes and matrix arrays such as UPSCODES. The scanning device includes laser or light emitting diodes for emitting at least two light beams of the same or different wavelengths. The light beams may be visible to the human eye, and the beams are optically directed to form one or two scan lines to scan portions of a symbol. Dual photosensor(s) or a charge coupled device detects light reflected from the different portions of the symbol. The charge coupled device can be used to detect either reflected ambient light or the reflected visible light from the beams emitted by the diodes. The photosensors generate signals corresponding to the detected light which can be processed simultaneously. The device is particularly useful in reading two dimensional or more complex symbols. Methods for reading indicia are also described.

Abstract: A scanner determines whether a target is a bar code symbol and, if so, whether that symbol is one-dimensional or two-dimensional. For two-dimensional symbols, the scanner aligns a scanning pattern with the symbol and expands the scanning pattern to reach only to the top and bottom edges of the symbol, not beyond. The scanner also has a microprocessor-control scanning engine that uses a coil to drive a scanning element and pick up feed back signals from the scanning element. A pulse-width-modulated regulator also provides fast and efficient operation for driving the coil. The scanning engine can also be designed to generate a pattern that precesses across the target, and a powerful interface to the scanning engine allows decoding and control logic to work efficiently with and independently of the scan engine.

Abstract: A scanner determines whether a target is a bar code symbol and, if so, whether that symbol is one-dimensional or two-dimensional. For two-dimensional symbols, the scanner aligns a scanning pattern with the symbol and expands the scanning pattern to reach only to the top and bottom edges of the symbol, not beyond. The scanner also has a microprocessor-control scanning engine that uses a coil to drive a scanning element and pick up feed back signals from the scanning element. A pulse-width-modulated regulator also provides fast and efficient operation for driving the coil. The scanning engine can also be designed to generate a pattern that precesses across the target, and a powerful interface to the scanning engine allows decoding and control logic to work efficiently with and independently of the scan engine.