Abstract: An electrospray ionization system used in mass spectrometry provides for improved current measurement. The system includes a fluid union, a fluid column coupled with a first port of the fluid union, a power source coupled with the fluid union and configured to apply a voltage potential to the fluid union, and an electrospray emitter coupled with a second port of the fluid union. The power source is coupled with the first port and configured to apply the voltage potential to the first port to restrict current leakage from the fluid union. The current sensing circuit is configured to determine an electrical current flow between the power source and the at least one of the fluid union and the first port.

Abstract: An electrospray ionization system used in mass spectrometry provides for improved current measurement. The system includes a fluid union, a fluid column coupled with a first port of the fluid union, a power source coupled with the fluid union and configured to apply a voltage potential to the fluid union, and an electrospray emitter coupled with a second port of the fluid union. The power source is coupled with the first port and configured to apply the voltage potential to the first port to restrict current leakage from the fluid union. The current sensing circuit is configured to determine an electrical current flow between the power source and the at least one of the fluid union and the first port.

Abstract: Packed-tip electrospray ionization (ESI) emitters for mass spectrometry are described. In one aspect an ESI emitter stores a first type of particle. A liquid chromatography (LC) column is coupled with the emitter via a junction. The LC column stores a different type of particle than the ESI emitter to facilitate better chromatographic and ESI performance.

Abstract: A detector network for an optical metrology system includes an analog to digital converter for each photodetector or detector array. Each analog to digital converter is connected to provide digitally encoded output from its associated detector. Each analog to digital converter is also connected to a hub. The hub receives commands from a processor and distributes them to the analog to digital converters. The converters sample the output of their associated detectors and return the digitized results to the hub. In turn, the hub passes the digitized results to the processor for analysis.

Abstract: The system and method herein provide a prealigner that has reduced sensitivity to distorting ambient light influences in the environment of a prealigner integrated in a metrology apparatus. A modulated signal is produced by a photo detector in response to modulated light that is partially shielded by wafer positioned in a gap between light source and detector. The pulsed signal is bandpass filtered and demodulated whereby only the difference between high- and low-levels of the pulsed signal are recognized. Flickering and DC components related to ambient light and other distorting operational influences are removed from the analysis unrecognized. Demodulation is synchronously accomplished together with a switching of the light source's power supply. For stable voltage levels of the power supply, a current source is buffered during off-intervals for a constant load on the current source.

Abstract: An object identification system and method detects the presence of a target object in a field of inspection and in one aspect of the invention, generates a first signal if the object is left in the field of inspection for more than a minimum threshold period of time. In a second aspect a second signal is generated if the object is introduced to the field of inspection more than a minimum threshold number of times (having been withdrawn from the field of inspection in the interim) within a minimum threshold period of time.

Abstract: A radio frequency identification system includes a transponder and a transponder reader. The transponder, responsive to an interrogation signal continuously transmitted by the transponder reader, generates a transponder signal modulated by an identification signal readable by the transponder reader. The identification signal includes a synchronization portion, a data portion, an output format identification portion, and an error detection portion. The output format identification portion is used by the reader to configure itself for communication with an attached controller. In another aspect of the invention, the transponder reader may be configured to read FSK as well as PSK encoded signals from the transponder.

Abstract: A proximity detection system which combines the advantages of an electrostatic (electric) field coupling mechanism with those of an electromagnetic coupling mechanism in order to overcome the disadvantages of the respective individual coupling mechanisms. The system includes a coded tag which is excited with an induction field, i.e., by using an electromagnetic coupling mechanism as has been done in the past in such proximity identification systems, but which transmits stored data back to the receiver using both an electric field coupling mechanism and an electromagnetic field coupling mechanism. The receiver, in turn, is provided with a novel preamplifier circuit arrangement, so that it can simultaneously receive signals via either or both of these coupling mechanisms.