Abstract: A hand-held bar code scanner has a removable boot to hold a field-replaceable optical element, which is sandwiched between an opening formed at the nose section of the scanner housing and the face section of the boot. The replaceable optical element can be, for example, a transparent element, filter, lens, or Brewster Window.

Abstract: An optical scanner unit has a window which transmits light from inside the scanner to a target, for example, a bar code, and receives light from a target into the scanner. The window is tilted at Brewster's angle to permit light from inside the scanner to exit the scanner without "exit reflection" of light off the interior of the window. The window also permits light returned from the scanned target to enter the scanner and be sensed by a photodetector therein. The same window may be used for light transmitted to the photodetector and from the light source. The window is disposed at Brewster's angle relative to the scanning beam at the center of scan, and is close to Brewster's angle over the entire scan.

Abstract: A hand-held bar code scanner has a field-replaceable optical element (250) such as a window using a rubber boot (110) to hold the window (250) proximate to the scanner housing (101) in front of the housing. The optical element is most typically a window but may also be a filter or lens.

Abstract: To enhance the effectiveness of personnel conducting inventory management functions, including data entry of information for products as to their presence, absence, or location, the operator-user is provided with a small and lightweight lapel data entry terminal which can be comfortably worn on a lapel of the operator's clothing, and which can be used to enter data into a remote data center. The lapel data entry terminal provides for acquisition and entry of data derived from verbal pronouncement of code data into a microphone which is coupled to a transmitter through a speech or voice recognition sub-assembly and an analog-to-digital converter sub-assembly. The lapel terminal provides for acquisition and entry of data derived from optical scanning of codes affixed to objects, for example, optical bar code patterns. Such optical codes are read by an optical code reader whose signal output is also coupled to the transmitter.