Abstract: A guided mode resonance (GMR) sensor assembly and system are provided. The GMR sensor includes a waveguide structure configured for operation at or near one or more leaky modes, a receiver for input light from a source of light onto the waveguide structure to cause one or more leaky TE and TM resonant modes and a detector for changes in one or more of the phase, waveshape and/or magnitude of each of a TE resonance and a TM resonance to permit distinguishing between first and second physical states of said waveguide structure or its immediate environment.

Abstract: An apparatus for measuring a distance such as, for example, a fly height distance. An apparatus includes a slider having an air bearing surface and an optical condenser assembly spaced apart from the air bearing surface of the slider. The optical condenser assembly includes an optical cap and an optical substrate having a first surface and a second surface. The first surface is spaced apart from the optical cap and the second surface is spaced apart from the air bearing surface of the slider.

Abstract: The invention is related to systems and methods for optically measuring conditions and characteristics related to vehicle tires. In one embodiment, a tire monitoring system comprises a grid, a camera, and a processor. The grid can be configured to deform in conjunction with a deformation of the tire. The camera can be mounted optically proximate the grid and configured to acquire an image of the grid. The processor can be in communication with the camera and configured detect the deformation of the tire from the image.

Abstract: A device for evaluating defects in the edge area of a wafer (6) is disclosed. The evaluation may also be performed automatically. In particular, the device includes three cameras (25, 26, 27), each provided with an objective (30), wherein a first camera (25) is arranged such that the first camera (25) is opposite to an edge area on the upper surface (6a) of the wafer (6), wherein a second camera (26) is arranged such that the second camera (26) is opposite to a front surface (6b) of the wafer (6), and wherein a third camera (27) is arranged such that the third camera (27) is opposite to an edge area on the lower surface (6c) of the wafer (6).

Abstract: Optical element having an optical surface, which optical surface is adapted to a non-spherical target shape, such that a long wave variation of the actual shape of the optical surface with respect to the target shape is limited to a maximum value of 0.2 nm, wherein the long wave variation includes only oscillations having a spatial wavelength equal to or larger than a minimum spatial wavelength of 10 mm.

Abstract: The present invention provides an appearance inspection apparatus that allows a user to give precedence to either defect detection performance or throughput. The appearance inspection apparatus allows a user to select the frequency of a digital image signal or the ratio of the frequency of the digital image signal to a sampling rate. Further, a user is allowed to select either throughput improvement or S/N improvement to prioritize.

Abstract: An optical fiber probe for an interferometric measuring device having a mechanical receptacle into which an optical fiber is inserted, having a fiber end piece which projects over the mechanical receptacle and contains optical components for guiding a measuring beam onto a measuring object, and having a reflection zone situated in the fiber for partial reflection of a light beam guided in the fiber. The reflection zone is situated in the fiber end piece. A method for manufacturing such an optical fiber probe. The fiber is separated at a predefined point, a partially reflecting coating is applied to at least one of the separation sites, and the two fiber parts are subsequently reconnected. The optical fiber probes may thus be manufactured with a long fiber end piece, which makes it possible to interferometrically measure deep cavities having a small diameter.

Abstract: A method of sensing a component held by a nozzle of a pick and place machine is provided. The method includes engaging a source of illumination and recording a reference background image when no component is held by the nozzle. Then, a component is adhered to the nozzle. A shadow image of the component is detected while the component is held by the nozzle. The detected shadow image of the component is adjusted based upon the recorded reference background image. Positional information relative to the component held on the nozzle is computed using the adjusted shadow image. The component is then mounted upon a workpiece using the positional information.

Abstract: The present invention provides a reticle inspection technology that enables a relative position between patterns to be evaluated for a pattern that may become a defect at the time of exposure to a sample, such as a wafer, in the double patterning technology on the same layer.

Abstract: A frequency swept laser source that generates an optical signal that is tuned over a spectral scan band at single discrete wavelengths associated with longitudinal modes of the swept laser source. Laser hopping over discrete single cavity modes allows long laser coherence length even under dynamic very high speed tuning conditions. A ramp drive to the laser is used to linearize laser frequency tuning. A beam splitter is used to divide the optical signal between a reference arm leading to a reference reflector and a sample arm leading to a sample. A detector system detects the optical signal from the reference arm and the sample arm for generating depth profiles and images of the sample.

Abstract: Apparatus and method for increasing the sensitivity in the detection of optical coherence tomography and low coherence interferometry (“LCI”) signals by detecting a parallel set of spectral bands, each band being a unique combination of optical frequencies. The LCI broad bandwidth source is split into N spectral bands. The N spectral bands are individually detected and processed to provide an increase in the signal-to-noise ratio by a factor of N. Each spectral band is detected by a separate photo detector and amplified. For each spectral band the signal is band pass filtered around the signal band by analog electronics and digitized, or, alternatively, the signal may be digitized and band pass filtered in software. As a consequence, the shot noise contribution to the signal is reduced by a factor equal to the number of spectral bands. The signal remains the same. The reduction of the shot noise increases the dynamic range and sensitivity of the system.

Abstract: A method for determining a defect during sample inspection involving charged particle beam imaging transforms a target charged particle microscopic image and its corresponding reference charged particle microscopic images each into a plurality of feature images, and then compares the feature images against each other. Each feature image captures and stresses a specific feature which is common to both the target and reference images. The feature images produced by the same operator are corresponding to each other. A distance between corresponding feature images is evaluated. Comparison between the target and reference images is made based on the evaluated distances to determine the presence of a defect within the target charged particle microscopic image.

Abstract: An interferometric tracking device is disclosed. A first grating is optically coupled to a second grading such that the second grating is rotationally offset from the first grating. Imaging optics are adapted to image light passing through the first and second gratings onto a focal plane array. A plurality of wedge plates are optically disposed between the imaging optics and the second grating, such that the wedge plates generate a plurality of spots on the FPA when light from a point source is incident upon the first grating.

Abstract: An improved condition testing system and method integrated into microelectronic circuits includes a structure including a semiconductor material with a target portion and a second portion for determining the presence and nature of various external (e.g. magnetic field, microwave, bioelectric or incident radiation) or internal stresses (e.g. binary circuit-state or analog signal recognition) or conditions acting upon the material. The target portion has a first feature when at least one of the following occurs: an external force is received by the second portion of the structure and an internal condition occurs in the target portion. The system and method further has a test grating determined and shaped and located to produce a first optical interference pattern when the target portion and the grating are exposed to non-invasive illumination and when the target portion has the first feature.

Abstract: The present invention relates to a measurement method of the chromatic dispersion of an optical waveguide using an optical interferometer with a broadband multi-wavelength light source and an optical spectrum analyzing apparatus, wherein one arm, called “reference arm” of the interferometer's two arms has an adjustable air spacing and the other arm, called “sample arm” can contain said optical waveguide to be measured, and including the following measurement and analysis steps: measuring interference spectra of the optical beam output exiting from the said interferometer with an optical spectrum analyzing apparatus when said optical waveguide is connected to said sample arm, and when said optical waveguide is not connected to said sample arm respectively; by adjusting the reference arm length for appearance of clear interference patterns; converting the wavelength-domain interference spectra into frequency-domain interference spectra and calculating phase difference values of the interference peaks of one of

Abstract: A method for out-of-plane displacement detection is disclosed. The out-of-plane displacement is detected by analyzing all the fringe density indexes calculated using the frequency-domain information extracted from a series of interference images of the sample vibrating at different frequencies. The present invention further discloses a method and an apparatus for resonant frequency identification by detecting the peak value of all the fringe indexes calculated at different scanning frequencies. With the identified resonant frequency, the full-field vibratory surface profile of the sample in various resonance modes can be reconstructed.

Abstract: The field of the invention is that of solid-state laser gyros used for the measurements of rotation speed or relative angular positions. This type of equipment is notably used for aeronautical applications. The object of the invention is to complete the optical devices necessary to control the instability of lasers by specific optical devices enabling elimination of the dead zone and of population inversion gratings exiting in the amplifying medium. An “all optical” solid-state laser is hence obtained without moveable parts, stable and without a dead zone. To this end, the laser gyro according to the invention comprises notably and optical assembly enabling a nonreciprocal optical phase-shift to be introduced between the counterpropagating modes; and control means allowing the phase-shift amplitude to be varied periodically around a mean value that is very approximately zero.

Abstract: A multi-beam interferometer, typically for use in Optical Coherence Tomography, comprising a multiple beam source, the source being arranged so as to provide, in use, a plurality of beams of light for use in the interferometer, the source comprising: a light source arranged to, in use, emit a beam of light; and a rattle plate comprising a first reflective surface and a second reflective surface facing one another, the second reflective surface being only partially reflective.

Abstract: Systems and methods for multispectral imaging.

Abstract: Techniques and devices for digitally resolving quadrature fringe signals from interferometers such as optical interferometers and interferometer-based sensing devices. In one implementation, two quadrature fringe signals from an interferometer which causes two signals in two signal paths to interfere with each other are sampled to obtain digital data samples from the two quadrature fringe signals. The digital data samples are used to perform a linear least square fitting to establish coefficients for an ellipse traced by the two quadrature fringe signals as a phase difference between the two signal paths changes. A pair of digital data samples are respectively obtained from the two quadrature signals at a given moment and are used to compute a corresponding phase difference between the two signal paths of the interferometer from established coefficients of the ellipse. The coefficient for the ellipse can be updated over time. This digital processing allows for real time processing.