Abstract: A polarimeter adapted for measurement of the concentration of glucose in a sample includes a laser beam passing through a first polarizer and an optical modulator and split into a measurement beam passing through a FIRST ANALYZER to a first detector coupled to a first amplifier and a reference beam passing through a SECOND ANALYZER to a second detector coupled to a second amplifier. Identical multiple filtering and summing operations are performed on outputs of the first and second amplifiers to produce a first &PSgr;2/2 signal and a first 2&bgr;&PSgr; signal in response to the measurement beam and a second &PSgr;2/2 signal and a second 2&bgr;&PSgr; signal in response to the reference beam. The measurement beam is stabilized by comparing the second &PSgr;2/2 signal to a first reference signal to produce a first error signal and comparing the second 2&bgr;&PSgr; signal to a second reference signal to produce a second error signal.

Abstract: A liquid crystal display circuit (9) comprises a recirculating shift register (14) having serial input and output terminals for receiving and generating binary data in bit serial format and a plurality of intermediate parallel output terminals for coupling display data to a liquid crystal display (LCD) (10). Display data are loaded into the shift register (14) during a display update mode and recirculated for display by the LCD (10) during a data refresh mode. Loading and recirculation of display data are controlled by logic circuitry (16) in a feedback loop (15, 17) of the recirculating shift register (14). To minimize DC buildup on the LCD (10), data inversion provided in the feedback loop causes periodic polarity reversal of data during recirculation. In addition, a shift register reset circuit (28) monitors the continuity of data being supplied to the LCD (10) for display.

Abstract: A hysteresis type battery charger includes a circuit for monitoring battery voltage and in response controlling a pass transistor to supply charging current to a battery. When the battery voltage is below a first predetermined value, high charging rate current is supplied to the battery; when the battery voltage is above a second predetermined value, the battery is supplied with trickle charging current. First and second light emitting diodes (LEDs) are selectively energized to indicate whether the battery is receiving high charging rate current or trickle charging current. The second LED is connected in circuit with the pass transistor to provide charging current foldback during excessive current demand, e.g., short circuit. The battery charger includes a low battery monitor that is energized when the expected battery lifetime is at a predetermined value, e.g., one hour.

Abstract: An apparatus and method are described for automatically correcting drift in automatic titrations, such as coulometric titrations of water. An endpoint detector provides a signal indicative of the state of the titration mixture and the detector signal is monitored by two comparators, responsive to titration mixture states on opposite sides of the endpoint and connected to means for controlling forward and back titration. At the end of a titration, the titration time and amount of titrant are stored in memory elements, and circuitry including an array of gates monitors the comparator signals during two post titration time periods to determine both the direction and rate of drift, and to correct the titration results for the amount of drift detected.