Abstract: The present disclosure is directed to simultaneously controlling peak pulse power and pulse energy in gas-discharge lasers. In an aspect, a radio-frequency power supply that is coupled to a gas-discharge laser is turned ON to initiate delivery of a laser pulse. The radio-frequency power supply is modulated ON/OFF to maintain the amplitude of the laser pulse at about a desired or prescribed value. Further, the radio-frequency power supply is turned OFF to terminate delivery of the laser pulse when the accumulated energy reaches reached a predefined energy threshold value.

Abstract: An interference signal S(t) is provided from interference between two beams directed along different paths. The signal S(t) is indicative of changes in an optical path difference n{tilde over (L)}(t) between the different paths, where n is an average refractive index along the different paths, {tilde over (L)}(t) is a total physical path difference between the different paths, and t is time. An error signal is provided to reduce errors in an estimate of {tilde over (L)}(t). The error signal is derived at least in part based on one or more collective properties of a distribution of multi-dimensional values. At least one of the multi-dimensional values in the distribution is generated from a plurality of samples of the signal S(t) (e.g., samples of the signal captured at different times).

Abstract: Systems and methods provide for simulating an effective touch on a touch screen sensor. A touch screen sensor includes a first surface, an opposing second surface, and one or more electrodes disposed on or proximate to the second surface. Signals are applied to the first and second surfaces in a manner which results in a simulated touch to a particular location of the touch screen sensor. In another approach, a plurality of voltage drive signals are applied at various touch surface regions of the touch screen sensor. A current flow resulting from application of the voltage drive signals is detected as the simulated touch. Touch simulation can be initiated locally or remotely as part of automated monitoring, testing, calibration, and/or servicing procedures. Results of a touch simulation procedure can be acquired and used locally or remotely to assess the operational fitness of the touch screen sensor over time.

Abstract: Systems and methods provide for simulating an effective touch on a touch screen sensor. A touch screen sensor includes a first surface, an opposing second surface, and one or more electrodes disposed on or proximate to the second surface. Signals are applied to the first and second surfaces in a manner which results in a simulated touch to a particular location of the touch screen sensor. In another approach, a plurality of voltage drive signals are applied at various touch surface regions of the touch screen sensor. A current flow resulting from application of the voltage drive signals is detected as the simulated touch. Touch simulation can be initiated locally or remotely as part of automated monitoring, testing, calibration, and/or servicing procedures. Results of a touch simulation procedure can be acquired and used locally or remotely to assess the operational fitness of the touch screen sensor over time.

Abstract: Systems and methods provide for simulating an effective touch on a touch screen sensor. A touch screen sensor includes a first surface, an opposing second surface, and one or more electrodes disposed on or proximate to the second surface. Signals are applied to the first and second surfaces in a manner which results in a simulated touch to a particular location of the touch screen sensor. In another approach, a plurality of voltage drive signals are applied at various touch surface regions of the touch screen sensor. A current flow resulting from application of the voltage drive signals is detected as the simulated touch. Touch simulation can be initiated locally or remotely as part of automated monitoring, testing, calibration, and/or servicing procedures. Results of a touch simulation procedure can be acquired and used locally or remotely to assess the operational fitness of the touch screen sensor over time.

Abstract: A method and apparatus are provided for determining the doping concentration profile of a specimen of semiconductor material. The apparatus includes a sensor assembly having a sensor tip which is mounted on an air bearing assembly. The air bearing assembly is suspended from a housing by a pair of bellows. In use, air is supplied to the air bearing assembly through the bellows causing the bellows to expand, lowering the sensor tip until the air bearing action stops the expansion. In other implementations of the invention, photocurrent or photovoltage are not used and the doping concentration profile is determined using the total capacitance, the capacitance of air, the DC bias voltage and the area of the electrode spaced from the specimen information.

Abstract: A method and apparatus are provided for determining the doping concentration profile of a specimen of semiconductor material. The specimen is positioned between a pair of electrodes, the specimen being disposed on one of the electrodes and being spaced form the other electrode by a nonconductive medium. In one implementation of the invention the nonconductive medium is air. A region of the surface of the specimen is illuminated with a beam of light of wavelengths shorter than that corresponding to the energy gap of the semiconductor material and which is intensity modulated at a predetermined frequency. A variable DC bias voltage is applied between the pair of electrodes, the variable DC bias voltage varying between that corresponding to accumulation and that corresponding to deep depletion for the specimen. The intensity of the light beam is low enough and the speed at which the DC bias voltage is varied is fast enough such that no inversion layer is formed at the surface of the specimen.

Abstract: A method for determining the doping concentration profile of a specimen of semiconductor material. The specimen is positioned between a pair of electrodes, the specimen being disposed on one of the electrodes and being spaced from the other electrode by an air gap. A signal is provided corresponding to the total capacitance between the two electrodes. A region of the surface of the specimen is illuminated with a beam of light of wavelengths shorter than that corresponding to the energy gap of the semiconductor material and which is intensity modulated at a predetermined frequency. A variable DC bias voltage is applied between the pair of electrodes, the variable bias voltage varying between that corresponding to accumulation and that corresponding to deep depletion for the specimen. The intensity of the light beam is low enough and the speed at which the DC bias voltage is varied is fast enough such that no inversion layer is formed at the surface of the specimen.

Abstract: A pair of orthogonally polarized optical beams that differ in frequency by a constant oscillator-generated reference frequency are directed through and traverse respective fixed and variable length paths of a heterodyne interferometer, following which the beams are mixed and directed to a detector that generates an electrical measurement signal having a phase that varies with changes in the variable path length. Changes in the measurement signal phase are determined by counting cycle-to-cycle phase changes of the reference frequency signal between sampling instants defined by time-spaced occurrences of a known phase of the measurement signal. The resulting count is simultaneously used to determine both changes in length of the variable length path and the elapsed time interval between the sampling instants.

Abstract: A dual high stability interferometer system capable of measuring linear and angular displacement simultaneously of a movable plane mirror (90) comprises a frequency stabilized laser input beam (10) which is divided into two parallel spatially displaced beams by a beamsplitter (14). An optical system (20) is disposed to produce a first output beam having two orthogonally polarized components in which the phase difference between the two components of the third output beam is related to four times the linear displacement of the movable plane mirror (90) at a first position. A polarizer (93) mixes the orthogonal components of the third output beam with the interference between the two polarization components being detected by a photodetector (94) which produces an electrical signal (96) from which a phase meter/accumulator (99) extracts the phase change, with this phase change being related to four times the linear displacement of the movable mirror (90) at the first position.

Abstract: A wavelength tracking compensator for a laser interferometer measurement system comprises a stable physical standard optical cavity and a double path, differential interferometer mounted on a baseplate. The interferometer monitors the apparent changes in the cavity's length caused by actual changes in the index of refraction of the surrounding air. The cavity is supported with a temperature compensated mount that utilizes the principle of differential thermal expansion of two different metals to create a mount which exactly matches the coefficient of expansion of the cavity material. A semi-kinematic mount supports the double path, differential interferometer and allows the interferometer to be accurately aligned to the cavity with three rotational degrees of freedom to prevent any cosine error in the cavity's optical path length measurement, to prevent polarization leakage, and to maximize optical power at the receiver.