Abstract: An apparatus for sensing the position of an object includes an irradiation portion for irradiating the object with continuous electromagnetic radiation, a detection portion for detecting electromagnetic radiation reflected by the object, and an output portion for supplying a change in an amplitude intensity or a phase of the electromagnetic radiation based on information obtained by the detection portion. The position of the object is detected based on information supplied from the output portion.

Abstract: An exposure apparatus including an illumination system which illuminates an original, and projection optics which project a pattern of the original illuminated by the illumination system onto a substrate. The apparatus includes an interferometer which forms an interference pattern including aberration information on the projection optics using a polarized light beam emitted from the illumination system, in which the interferometer is a common path interferometer in which two light beams forming interference pattern pass along a path in the projection optics, and a processor which calculates optical characteristics of the projection optics on the basis of the interference pattern formed by the interferometer. The illumination system including a polarization controller which sequentially generates at least three difference polarized light beams with respective polarization states different from each other.

Abstract: A measuring device for the optic measuring of an object 13a is provided, in particular for measuring a motion of the object. The device includes an interferometer 20 with a measuring beam exit 12, a reflection beam entry 14, an interfering beam exit 15, and a light source 1 for creating a light beam 8, an optic detector 16, which is arranged at the interfering beam exit 15 of the interferometer 20 such that a light beam exiting the interfering beam exit 15 impinges the detector and a signal processing unit 17 connected to the detector 16 being embodied such that they can measure measuring signals of the detector 16.

Abstract: The present invention relates to an disturbance sensing system, in particular an optical system in which a disturbance can be inferred. The system includes: a first waveguide portion and a second waveguide portion disposed in a side to side arrangement relative to one another; launch means for launching a first signal and a second signal onto the first waveguide portion and the second waveguide portion respectively, the first and second waveguide portions being optically coupled such that each of the transmitted first and second signals travels along each of the first and second waveguides; and, combining means for combining the transmitted first and second signals so as to produce a combination signal, the first and second signals being related to one another such that a disturbance in either one of the first and the second waveguide portions can be inferred from the combination signal.

Abstract: A tunable optical cavity can be tuned by relative movement between two reflection surfaces, such as by deforming elastomer spacers connected between mirrors or other light-reflective components that include the reflection surfaces. The optical cavity structure includes an analyte region in its light-transmissive region, and presence of analyte in the analyte region affects output light when the optical cavity is tuned to a set of positions. Electrodes that cause deformation of the spacers can also be used to capacitively sense the distance between them. Control circuitry that provides tuning signals can cause continuous movement across a range of positions, allowing continuous photosensing of analyte-affected output light by a detector.

Abstract: In a displacement measurement apparatus using light interference, a probe light path is spatially separated from a reference light path. Therefore, when a temperature or refractive index distribution by a fluctuation of air or the like, or a mechanical vibration is generated, an optical path difference fluctuates between both of the optical paths, and a measurement error is generated. In the solution, an optical axis of probe light is brought close to that of reference light by a distance which is not influenced by any disturbance, a sample is irradiated with the probe light, a reference surface is irradiated with the reference light, reflected light beams are allowed to interfere with each other, and a displacement of the sample is obtained from the resultant interference light to thereby prevent the measurement error from being generated by the fluctuation of the optical path difference.

Abstract: An optical spectrum analyzer detects a light output that is dependent on the frequency of light in a wavelength range of light to be measured. The optical spectrum analyzer includes a waveguide acousto-optic tunable filter including a piezoelectric substrate, optical waveguides, and an IDT, a light source for providing, to the waveguide acousto-optic tunable filter, reference light having a particular wavelength outside the wavelength range, a driving circuit for providing, to the waveguide acousto-optic tunable filter, a high frequency signal for exciting an IDT, and an arithmetic device that, on the basis of the wavelength of selected light when reference light is incident, and an exciting frequency, corrects the wavelength of the selected light, which is obtained from the light to be measured.

Abstract: The present invention provides the capability of ascertaining, through a quick and simple measurement, locations on a structure that may have experienced damage that could result in reduced structure lifetime, strength, or reliability. The sensing element is a connectorized section of polarization maintaining (“PM”) optical fiber, where a length of PM fiber represents a fully distributed sensor array. Stress-induced changes to the sensor are measured through white-light Polarimetric interferometry. The output of the measurement is a data array representing the stress concentration magnitude at an array of locations along the length of the sensor. In an application, the knowledge of the optical fiber position on the structure, coupled with the measurement of stress locations along the fiber length, allows the user to determine locations on the structure with large stress concentrations. These locations may signify structural damage.

Abstract: Frequency domain optical coherence imaging systems have an optical source, an optical detector and an optical transmission path between the optical source and the optical detector. The optical transmission path between the optical source and the optical detector reduces an effective linewidth of the imaging system. The optical source may be a broadband source and the optical transmission path may include a periodic optical filter.

Abstract: A wavelength measurement or monitoring system provides a tunable Fabry-Perot optical filter. At least one known light source is used to calibrate and correlate separate wavelength bands scanned by the tunable Fabry-Perot optical filter. At least one wavelength reference is utilized to calibrate at least one wavelength band of the tunable Fabry-Perot optical filter. The wavelength reference is transferred to a wavelength band that is identified for measurement when the wavelength reference is not in a wavelength band identified for measurement by the tunable Fabry-Perot optical filter. An unknown optical signal is scanned through the tunable Fabry-Perot optical filter. The wavelengths in the unknown optical signal are specified.

Abstract: The focus of the collimating lens in the optical train of a Fizeau interferometer is adjusted to change the power of the test beam illuminating the transmission sphere. As a result, the rays can be made sufficiently perpendicular to the reference surface to eliminate the chromatic focus shift and non-common path errors produced by a light source of wavelength different from the design wavelength of the transmission sphere. By making the position of the collimating lens relative to the beam expander adjustable along the optical axis over some small range, illumination sources of various wavelength can be used in the same interferometer.

Abstract: This invention uses an interferometric fiber optic sensor, particularly a Sagnac or Michelson interferometer, in a first fiber to monitor a sensing length of the first fiber and to detect disturbances. Signals indicating disturbances are classified as being of interest or not of interest, depending on predetermined criteria. Disturbances of interest can be, for example, the breaking of reinforcement wires in concrete pipe, the breaking of wires in suspension cables, a fire, a pipeline leak, or an intrusion. A location sensor system is used to determine the location of disturbances of interest, and to confirm the interferometer signal to reduce noise. The location sensor system is a fiber optic sensor, such as a phase OTDR sensor or a Brillouin effect sensor, which can detect the location of events it senses. It is present either in the first fiber or in a separate fiber laid adjacent the first fiber along its sensing length, as for example in the same optical cable.

Abstract: The invention provides a method and apparatus for evaluating the quality of microelectromechanical devices having deformable and deflectable members using resonation techniques. Specifically, product quality characterized in terms of uniformity of the deformable and deflectable elements is inspected with an optical resonance mapping mechanism on a wafer-level.

Abstract: A system for determining at least one condition of a seal including an optical fiber for transmitting light from a light source. The optical fiber is embedded in the seal and operatively coupled to an interferometric system. The interferometric system is operatively coupled to a processor. The interferometric system provides the processor with information relating to wear of the optical fiber, and the processor determines wear of the seal, rate of wear and remaining useful life of the seal based on the information relating to wear of the optical fiber.

Abstract: A light scattering sensing system and method. In one embodiment, the system includes a sample branch configured to collect light signals backscattered from scattering centers contained in a coherence volume of a medium under evaluation, the sample branch including a multi-mode optical waveguide. In one embodiment, the method includes radiating low-coherence light into a scattering medium using a multi-mode optical waveguide, and collecting light signals backscattered by the scattering centers and light reflected by an end surface of the multi-mode optical waveguide using the multi-mode optical waveguide.

Abstract: In general, in one aspect, the invention features an apparatus including a multi-axis interferometer configured to produce at least three output beams each including interferometric information about a distance between the interferometer and a measurement object along a corresponding measurement axis, wherein at least three of the measurement axes are in a common plane, wherein the output beams each include a component that makes a pass to the measurement object along a common beam path.

Abstract: The invention is directed to a system and method for implementing process control for paper elasticity and thickness using sonic NDE techniques. The system may, for example, generate ultrasound waves in a test object during the manufacturing process. A detector such as an interferometer may be used to detect the ultrasound waves. An interpreter or analyzer may determine the thickness and/or elastic properties of paper from the waves. Then, a control system may determine and implement an appropriate control action on the process.

Abstract: The apparatus according to the invention comprises an object lens which can operate in at least two different measuring modes. In a first, interference mode a workpiece is measured by means of interference optometry. In a second, imaging measuring mode an optical image is produced, for example, on a camera-like detector array and may be applied to an image processing routine. Switching between the two measuring modes is performed by the type of illumination of the object lens and an element which is disposed preferably in the reference beam path of an interferometer and which activates or deactivates the reference beam path dependent on the spectral composition of the utilized light. In this manner a simple and rapid changeover between the two measuring modes is provided, without the need for replacing or even for moving the object lens.

Abstract: A method and apparatus for wavefront analysis including obtaining a plurality of differently phase changed transformed wavefronts corresponding to a wavefront being analyzed which has an amplitude and a phase, obtaining a plurality of intensity maps of the plurality of phase changed transformed wavefronts and employing the plurality of intensity maps to obtain an output indicating the amplitude and phase of the wavefront being analyzed.

Abstract: A component comprises a coil for the supply by induction of the component and for the inductive bidirectional transfer with the station of a signal representative of data. Means for processing said signal are supplied by the coil and are produced in integrated technology on the substrate of the component. The turns of the coil are produced in flat integrated technology by metallization on the surface of the component. The integral coil occupies at least 50% of the total surface of the component.