Abstract: An optical fiber-based sensor system includes a sensing optical fiber having fiber gratings that reflect light at respective wavelengths. A first fiber grating reflects light at a first wavelength. A second fiber grating reflects light at a second wavelength. The system also has a reference optical fiber. An optical read-out arrangement generates light at the first and second wavelengths. The light is injected in the sensing optical fiber and in the reference optical fiber. A first phase difference is measured between light at the first wavelength emanating from the sensing optical fiber and the reference optical fiber. In addition, a second phase difference is measured between light at the second wavelength emanating from the sensing optical fiber the reference optical fiber. A measurement result is based on a difference between the first phase difference and the second phase difference.

Abstract: An optical sensor system includes an optical sensor arrangement that includes a Fabry-Perot structure having two reflective surfaces spaced apart at a distance from each other. A spectral acquisition arrangement acquires successive spectral responses from the optical sensor arrangement during successive time intervals. A spectral analysis arrangement detects a periodicity in at least one of the successive spectral responses that have been acquired. The spectral analysis arrangement further detects a phase evolution of the periodicity throughout the successive spectral responses. The phase evolution of the periodicity provides a relatively precise measurement of a variation in an optical path length between the two reflective surfaces of the Fabry-Perot structure. A variation in a physical quantity can cause the variation in the optical path length. Accordingly, a relatively precise measurement of the physical quantity can be achieved.

Abstract: An optical fiber-based sensor system includes a sensing optical fiber having fiber gratings that reflect light at respective wavelengths. A first fiber grating reflects light at a first wavelength. A second fiber grating reflects light at a second wavelength. The system also has a reference optical fiber. An optical read-out arrangement generates light at the first and second wavelengths. The light is injected in the sensing optical fiber and in the reference optical fiber. A first phase difference is measured between light at the first wavelength emanating from the sensing optical fiber and the reference optical fiber. In addition, a second phase difference is measured between light at the second wavelength emanating from the sensing optical fiber the reference optical fiber. A measurement result is based on a difference between the first phase difference and the second phase difference.

Abstract: An optical sensor system includes an optical sensor arrangement that includes a Fabry-Perot structure having two reflective surfaces spaced apart at a distance from each other. A spectral acquisition arrangement acquires successive spectral responses from the optical sensor arrangement during successive time intervals. A spectral analysis arrangement detects a periodicity in at least one of the successive spectral responses that have been acquired. The spectral analysis arrangement further detects a phase evolution of the periodicity throughout the successive spectral responses. The phase evolution of the periodicity provides a relatively precise measurement of a variation in an optical path length between the two reflective surfaces of the Fabry-Perot structure. A variation in a physical quantity can cause the variation in the optical path length. Accordingly, a relatively precise measurement of the physical quantity can be achieved.

Abstract: An active vibration isolation and damping system (11) comprising a payload (12) that has to be isolated or damped, a vibration sensor (14) for detecting a vibration of the payload, an actuator (15) for moving the payload relative to a bearing body (13) supporting the payload, and a controller (16) for providing the actuator with a signal that is representative for the vibration. The system provides a solution for the tilting problem by applying a vibration sensor that has a low stiffness connection to the payload (12) for rotation along an axis (17) perpendicular to the gravitational force (18), and a high stiffness connection to the payload (12) for the vibration detectable with the vibration sensor.

Abstract: An object is mounted on a surface of a sample carrier. Properties of the surface of the object are measured and/or modified by means of a plurality of independently movable heads, each comprising a microscopic probe. The heads being located between the surface of a reference grid plate and the surface of the sample carrier. Head specific target locations are selected for the heads. Each head is moved over the surface of the reference grid plate, to the target location of the head. During movement a position of the head is determined from markings on the reference grid plate sensed by sensor in the head. When the sensor has indicated that the head is at the target location selected for the head a force between the head and the reference grid plate is switched to seat and/or clamp the head on the reference grid plate.

Abstract: A scanning probe microscopy device for mapping nanostructures on a sample surface of a sample is provided. The device may comprise a plurality probes for scanning the sample surface, and one or more motion actuators for enabling motion of the probes relative to the sample, wherein each of the plurality of probes comprises a probing tip mounted on a cantilever arranged for bringing the probing tip in contact with the sampling surface for enabling the scanning. The device may further comprise a plurality of Z-position detectors for determining a position of each probing tip along a Z-direction when the probing tip is in contact with the sample surface, wherein the Z-direction is a direction transverse to the sample surface, for enabling mapping of the nanostructures.

Abstract: An object is mounted on a surface of a sample carrier. Properties of the surface of the object are measured and/or modified by means of a plurality of independently movable heads, each comprising a microscopic probe. The heads being located between the surface of a reference grid plate and the surface of the sample carrier. Head specific target locations are selected for the heads. Each head is moved over the surface of the reference grid plate, to the target location of the head. During movement a position of the head is determined from markings on the reference grid plate sensed by sensor in the head. When the sensor has indicated that the head is at the target location selected for the head a force between the head and the reference grid plate is switched to seat and/or clamp the head on the reference grid plate.

Abstract: A scanning probe microscopy device for mapping nanostructures on a sample surface of a sample is provided. The device may comprise a plurality probes for scanning the sample surface, and one or more motion actuators for enabling motion of the probes relative to the sample, wherein each of the plurality of probes comprises a probing tip mounted on a cantilever arranged for bringing the probing tip in contact with the sampling surface for enabling the scanning. The device may further comprise a plurality of Z-position detectors for determining a position of each probing tip along a Z-direction when the probing tip is in contact with the sample surface, wherein the Z-direction is a direction transverse to the sample surface, for enabling mapping of the nanostructures.

Abstract: An active vibration isolation and damping system (11) comprising a payload (12) that has to be isolated or damped, a vibration sensor (14) for detecting a vibration of the payload, an actuator (15) for moving the payload relative to a bearing body (13) supporting the payload, and a controller (16) for providing the actuator with a signal that is representative for the vibration. The system provides a solution for the tilting problem by applying a vibration sensor that has a low stiffness connection to the payload (12) for rotation along an axis (17) perpendicular to the gravitational force (18), and a high stiffness connection to the payload (12) for the vibration detectable with the vibration sensor.

Abstract: A vibration sensor comprises a reference mass, a resilient element supporting the reference mass, and a base supporting the resilient element, and further comprises a displacement sensor for determining the distance between the reference mass and the base. In accordance with the invention the vibration sensor comprises an actuator that is situated between the resilient element and the base, a second displacement sensor, and a controller for providing an output signal to the actuator.