Abstract: A portable bar code scanner includes a base member and a overhanging scanning housing secured to the base member. A laser power supply mounted in the housing outputs a laser beam along a first light path directed to a compact optical system in the housing which reflects the laser beam along a second light path which intersects the first light path at approximately ninety degress to scan a coded label positioned below the scaning housing. A collection lens mounted in the housing collects and directs the reflected light from the coded label to a detector which generates electrical signals for transmission over a cable to a processor.

Abstract: A checkout counter having an optical scanning unit located therein and includes a surface portion comprising a scale apparatus which includes a transparent portion enabling scanning beams projected by the optical scanner unit to be transmitted through the scale apparatus for reading a coded label on a merchandise item positioned on the scale apparatus. The scale apparatus generates data signals representing the weight of the merchandise item which are then transmitted to a processor means which also receives data signals from the scanning unit identifying the merchandise item. The processor means will generate the price of the merchandise item using the data signals received. The price of the merchandise item is then displayed on a display unit and printed by a printing unit on a customer's receipt.

Abstract: Imidazole derivatives which are useful intermediates for the production of compounds having pharmacological activity at histamine H.sub.2 receptors. A specific compound of the present invention is 4-(4-aminobutyl)-1,3-dihydro-5-methyl-2H-imidazole-2-thione, hereinafter referred to as 4-(4-Aminobutyl)-5-methylimidazole-2-thione.

Abstract: An optical reader control system is disclosed wherein signals generated from detecting means positioned upstream and downstream of the optical reader control the operation of the optical reader to enforce the movement of a merchandise item past the optical reader within a predetermined path. Logic circuitry is disclosed for processing the detecting means signals for determining the occurrence of a valid read operation by the optical reader.