Abstract: A modulated reflectance measurement system includes three monochromatic diode-based lasers. Each laser can operate as a probe beam or as a pump beam source. The laser outputs are redirected using a series of mirrors and beam splitters to reach an objective lens. The objective lens focuses the laser outputs on a sample. Reflected energy returns through objective and is redirected by a beam splitter to a detector. A lock-in amplifier converts the output of the detector to produce quadrature (Q) and in-phase (I) signals for analysis. A Processor uses the Q and/or I signals to analyze the sample. By changing the number of lasers used as pump or probe beam sources, the measurement system can be optimized to measure a range of different samples types.

Abstract: A current mirror method is provided that can be utilized to evaluate thermal issues is silicon-on-insulator (SOI) bipolar junction transistors (BJTs). The method significantly improves safe operating area (SOA) measurement sensitivity. Unlike conventional methods, the current mirror method can provide quantitative analysis of the BJTs thermal instability over a wide power range, even in the apparent SOA of the device. This method can also predict and evaluate SOA with respect to emitter ballast resistance and current crowding.

Abstract: Laser systems have a line-narrowed master oscillator and a power oscillator for amplifying the output of the master oscillator. The power oscillator includes optical arrangements for limiting the bandwidth of radiation that can be amplified. The limited amplification bandwidth of the power oscillator is relatively broad compared to that of the output of the master oscillator, but narrower than would be the case without the bandwidth limiting arrangements. The bandwidth narrowing arrangements of the power oscillator function primarily to restrict the bandwidth of amplified spontaneous emission generated by the power oscillator.

Abstract: A projection display including a one-dimensional light modulator includes an optical arrangement for projecting light from a laser onto the modulator in the form of a line of light. Light from the laser is divided to create in effect a two-dimensional array of mutually incoherent light sources. Light from one axis of the array is projected onto the modulator to form the length of the line of light and light from the other axis of the array is projected onto the modulator to form the width of the line of light. Division of the light is accomplished without the use of any moving component.

Abstract: Sequential digital integrated circuits have stable state nodes that are capable of retaining their state (logic value) even in the absence of any input directly driving these points. However, in addition to stable state nodes, some custom-designed digital circuits have so-called transient state nodes. A transient state node is defined as node that can directly affect the value of a stable state node and is combinatorially driven by inputs of the circuit, but the transition delay from at least one input to the node is greater than a predefined threshold value. Identifying such transient state nodes, along with the stable state nodes, is critical for the efficient simulation of custom digital circuits by a hierarchical device level digital simulator. A method is provided herein for identifying transient state nodes in a digital circuit, given the circuit's netlist and the identity of the stable state nodes in the circuit.

Abstract: A CO2 laser has a resonator mirror that oscillates about an axis perpendicular to the resonator axis through an angular range of oscillation sufficient that the resonator is only able to deliver radiation for a fraction of an oscillation period of the mirror. In one example of the laser, the oscillating mirror is an end-mirror of the resonator. In another example, the oscillating mirror is a fold mirror of the resonator.

Abstract: In a photomask projection system, a photomask mask is illuminated by light from two lasers. A beam from one of the lasers is mixed with a beam from the other laser to provide two mixed beams each containing of portion of the beams from both lasers. The mixed beams are directed at an angle to each other and intersect on the photomask.

Abstract: A laser-resonator terminated by two end mirrors is folded by a plurality of OPS-structures and a plurality of fold-mirrors. The OPS-structures are energized by focused radiation from diode-laser bars. The fold-mirrors are configured and arranged with respect to the OPS-structures and the end-mirrors such that a beam of laser radiation circulating in the resonator has about the same dimensions on each OPS-structure.

Abstract: An in vivo screening assay for identifying an agent that interferes with T cell activation and/or -differentiation and/or modulation of other inflammatory effector cells.

Abstract: A method is disclosed for determining peak carrier concentration in ultra shallow junctions of semiconductor samples. A region of the surface of the sample is periodically excited. The effects of the excitation are monitored by a probe beam. Synchronous detection produces in-phase (I) and quadrature (Q) signals. These signals are compared to signals obtained from calibration samples to evaluate peak carrier concentration.

Abstract: A motorized head supporting and positioning apparatus is disclosed, such as is useful for eye examination or treatment. The apparatus includes head-receiving supports, which can include a forehead rest and a chinrest, which can be linked by a single arm assembly. A main assembly of the apparatus contains a motor assembly, which can include three motors driven in a coupled manner to guide a head along a three-dimensional path at a speed that is comfortable to the patient. The apparatus can be relatively compact, owing at least in part to a pivoted approximate Z-axis movement along the optical axis. In addition to open-loop operation, the apparatus can be used with a tracking subsystem to achieve closed-loop positioning in real time, as well as to enable the activation of an examination/treatment instrument when the eye is brought within an acceptable tolerance of a desired position.

Abstract: Laser apparatus is disclosed in which fundamental-wavelength optical pulses delivered from a mode-locked laser resonator at a pulse-repetition frequency (PRF) are converted to harmonic-wavelength pulses in an optical delay loop. One example is disclosed in which the harmonic-wavelength pulses are delivered directly from the delay loop. Another example is disclosed in which the harmonic-wavelength pulses are divided by the delay loop into a number of temporally spaced-apart replicas thereof, and the delay loop delivers bursts of replicas of different one of the harmonic wavelength pulses at a burst-repetition frequency equal to or a multiple of the PRF of the resonator.

Abstract: An apparatus for scatterometry measurements is disclosed. The apparatus includes a modulated pump source for exciting the sample. A separate probe beam is directed to interact with the sample and the modulated optical response is measured. The measured data is subjected to a scatterometry analysis in order to evaluate geometrical sample features that induce light scattering.

Abstract: An optical inspection device includes a light source for generating a probe beam. The probe beam is focused onto a sample to create a spread of angles of incidence. After reflecting from the sample, the light is imaged onto a two dimensional array of photodetectors. Prior to reaching the detector array, the beam is passed through a rotating compensator. A processor functions to evaluate the sample by analyzing the output of the photodetectors lying along one or more azimuthal angles and at different compensator positions.

Abstract: An optical fiber assembly includes a clad optical fiber having an end-cap thereon. Radiation is focused into the optical fiber via the end-cap. A roughened portion of the fiber cladding behind the end-cap allows any radiation focused into the fiber and propagating in the cladding to escape the optical fiber. A concave reflector surrounding the optical fiber reflects the escaped radiation away from the fiber assembly. A connector for connecting the optical fiber to a laser includes an air-cooled beam-dump for receiving the radiation reflected away from the optical fiber.

Abstract: An accurate measure of eye length can be obtained using concurrent OCT measurements. A position OCT device can be used to continually monitor the position of the front surface of the cornea, while a distance OCT device can determine the apparent distance between the front surface of the cornea and the front surface of the retina. Since the eye is likely to move during the period of time between measurements of the cornea and retina, the monitored position of the cornea can be used to correct the apparent length measurement by the amount of eye movement over that period of time, in order to obtain an accurate measure of eye length. In some embodiments a single OCT device can serve the dual role of monitoring eye position while making eye length measurements.

Abstract: A test methodology is provided for testing metal-insulator-metal (MIM) capacitor structures under high temperatures at the wafer level. A resistor is formed on a region of dielectric isolation material formed in a semiconductor substrate. The MIM capacitor is formed over the resistor and separated therefrom by dielectric material. A metal thermometer, formed from the same material as the plates of the MIM capacitor, is placed above the resistor and in close proximity to the capacitor. High current is forced through the resistor, causing both the metal thermometer and the MIM capacitor to heat up along with the resistor. The change in resistance of the metal thermometer is monitored. Using the known temperature coefficient of resistance (TCR) for the metal used to form both the capacitor and the thermometer, changes in the measured resistance of the metal thermometer are converted to temperature.

Abstract: The present invention is an alternative Fourier domain optical coherence system (FD-OCT) and its associated method. The system comprises a swept multi-wavelength laser, an optical interferometer and a multi-channel receiver. By employing a multi-wavelength laser, the sweeping range for each lasing wavelength is substantially reduced as compared to a pure swept single wavelength laser that needs to cover the same overall spectral range. The overall spectral interferogram is divided over the individual channels of the multi-channel receiver and can be re-constructed through processing of the data from each channel detector. In addition to a substantial increase in the speed of each axial scan, the cost of invented FD-OCT system can also be substantially less than that of a pure swept source OCT or a pure spectral domain OCT system.

Abstract: An interferometer configured for use in optical coherence domain (OCT) reflectometry systems is disclosed. In the preferred embodiments, efficient routing of light and a balanced detection arrangement provide a high signal to noise ratio. In a first set of embodiments, a 3×3 coupler is used to split light along separate sample and reference paths and also for combining light returning from those paths and supplying the interfered collected light to the detection system. In an alternate set of embodiments, a pair of cascaded 2×2 couplers provides a similar function. The interferometer can be used with various OCT modalities including time-domain and frequency domain approaches.

Abstract: A frequency-conversion arrangement including one or more optically nonlinear crystals is located in an enclosure. Radiation residual from the frequency conversion is directed into an optical fiber having one end in the enclosure for receiving the residual radiation and an opposite end outside of the enclosure for disposing of the residual radiation outside of the enclosure.