Abstract: An external optical feedback element (108) for tuning an output beam of a gas laser (102) having multiple wavelengths includes a partially reflective optical element (108) positioned on a beam path of the output beam (106) outside of an internal optical cavity of the gas laser (102), and a stage (114) to support the optical element and adjust rotation, horizontal tilt angle, and vertical tilt angle of the optical element with respect to the beam path. The output beam (106) is partially reflected at the optical element (108) and fed back into the internal optical cavity of the gas laser (102), with the intensity varying for multiple wavelengths and adjusted by changing rotation, horizontal tilt angle and vertical tilt angle of the optical element. Thereby, a variable feedback of the output beam into the internal optical cavity of the gas laser is provided, which leads to a selective output wavelength of the gas laser, either at a single line or at multiple lines simultaneously.

Abstract: A machine vision system that uses an imager to capture an optical image of a target object that may contain a liquid. The target object is illuminated by an illumination source positioned oppositely from the imager and a predetermined pattern is positioned between the illumination source and the target object so that the imager will capture optical images of the background pattern through any liquid positioned in the target object. A processor is programmed to analyze captured images to detect any distortions of the pattern that are attributable to the presence of a liquid in the target object.

Abstract: An absolute position encoder includes a position location medium containing position identifier code words providing absolute position indications, and an optical source, an optical detector, an optics subsystem and a code word decoder. The optics subsystem focuses a source beam onto the position location medium and directs a return beam to the optical detector, detects a focus condition from the return beam, and automatically adjusts focus of the source beam to maintain a predetermined focus condition during operation. The code word decoder responds to the detector signal to detect a code word and generate a decoder output indicative of a corresponding code word value and corresponding detected position.

Abstract: A machine vision system that uses an imager to capture an optical image of a target object that may contain a liquid. The target object is illuminated by an illumination source positioned oppositely from the imager and a predetermined pattern is positioned between the illumination source and the target object so that the imager will capture optical images of the background pattern through any liquid positioned in the target object. A processor is programmed to analyze captured images to detect any distortions of the pattern that are attributable to the presence of a liquid in the target object.

Abstract: A method is disclosed of fabricating a mirror for use in limited rotation motor systems, said method comprising the steps of providing a mirror structure including at least one wall section, and exposing the at least one wall section to a fluid etching agent to thereby provide chemical milling of the mirror structure.

Abstract: An external optical feedback element (108) for tuning an output beam of a gas laser (102) having multiple wavelengths includes a partially reflective optical element (108) positioned on a beam path of the output beam (106) outside of an internal optical cavity of the gas laser (102), and a stage (114) to support the optical element and adjust rotation, horizontal tilt angle, and vertical tilt angle of the optical element with respect to the beam path. The output beam (106) is partially reflected at the optical element (108) and fed back into the internal optical cavity of the gas laser (102), with the intensity varying for multiple wavelengths and adjusted by changing rotation, horizontal tilt angle and vertical tilt angle of the optical element. Thereby, a variable feedback of the output beam into the internal optical cavity of the gas laser is provided, which leads to a selective output wavelength of the gas laser, either at a single line or at multiple lines simultaneously.

Abstract: A communication system that involves superimposing data over DC power. The data takes the form of high bitrate digital signals, where the bitrate is much higher than 0 Hz (DC); this separation allows the AC signal to be easily separated from the DC power. The physical system consists of a two conductor cable, and integration is modular, in that multiple slaves can be connected and disconnected to a master through a routing bus also comprising two conductors. The master can communicate bi-directionally with the slave(s), and the data is encoded using DC-balanced encoding in an FPGA. The data is sent to and from a differential signaling transmitter/receiver pairs at each end of the cable. The system is may be used with position sensors, and provides the benefit of reducing cable costs and sensor size due to the decrease in number of conductors and elimination of power components in the sensor.

Abstract: An optical position encoder includes a scale having multiple tracks separated in a direction perpendicular to travel, the tracks including an incremental track and an absolute track, the scale interacting with an incident first light beam to generate a second light beam having components carrying respective optical patterns produced by the incremental track and absolute track respectively. The encoder further includes a set of optical detectors including at least first and second detector arrays of differing properties to detect the respective optical patterns produced by the incremental track and absolute track respectively, each of the first and second detector arrays spanning multiple tracks of the scale and configured to respond to a respective detector-specific component of the second light beam more strongly than to another component of the second beam specific to another of the detector arrays.

Abstract: A communication system that involves superimposing data over DC power. The data takes the form of high bitrate digital signals, where the bitrate is much higher than 0 Hz (DC); this separation allows the AC signal to be easily separated from the DC power. The physical system consists of a two conductor cable, and integration is modular, in that multiple slaves can be connected and disconnected to a master through a routing bus also comprising two conductors. The master can communicate bi-directionally with the slave(s), and the data is encoded using DC-balanced encoding in an FPGA. The data is sent to and from a differential signaling transmitter/receiver pairs at each end of the cable. The system is may be used with position sensors, and provides the benefit of reducing cable costs and sensor size due to the decrease in number of conductors and elimination of power components in the sensor.

Abstract: A system for controlling whether a battery powered device tethered to a host via a Universal Serial Bus (USB) interface will charge its battery via the USB connection. A USB interface adapter is programmed to control charging of the device battery based on whether a standard data terminal ready (DTR) signal is received from the host through a USB to RS-232 converter. Data packets are sent via the USB data line and interpreted as a DTR signal by the USB to Serial adapter. The dedicated DTR output pin from the adapter is thus used to control the charging circuit.

Abstract: Phase estimation apparatus processes sensor signals from sensors to estimate a phase of a periodically varying state of an object, such as position of a moving object. A phase estimation processor applies a first correlation calculation to simultaneously collected samples of the sensor signals to generate first quadrature values, where the first correlation calculation employs variable calculation values, and applies a phase calculation to the first quadrature values to generate the phase estimation. A pre-quadrature calibration circuit applies respective second correlation calculations to respective sequences of samples of the sensor signals individually to generate second quadrature values for each of the sensor signals, and applies phase and/or magnitude calculations to the sets of second quadrature values to generate the variable calculation values for the first correlation calculation, thereby compensate for the error component and improve accuracy of the estimated phase.