Abstract: A method for determining characteristics of a structure is disclosed. The method comprises repetitively irradiating the structure with a transient continuous wave electromagnetic radiation and capturing as a function of time a transient part of the reflection or transmission of the transient continuous wave electromagnetic radiation reflected at or transmitted through the different interfaces of layer-based structure. The method furthermore comprises deriving from the transient part of the reflected or transmitted transient continuous wave electromagnetic radiation as function of time information regarding different contributions in the transient part of the reflected or transmitted transient continuous wave electromagnetic radiation stemming from the reflections at different interfaces of the structure and determining from said information at least geometric information and/or electromagnetic properties of the one or more materials of the structure. A corresponding system also is claimed.

Abstract: A method for determining characteristics of a structure is disclosed. The method comprises repetitively irradiating the structure with a transient continuous wave electromagnetic radiation and capturing as a function of time a transient part of the reflection or transmission of the transient continuous wave electromagnetic radiation reflected at or transmitted through the different interfaces of layer-based structure. The method furthermore comprises deriving from the transient part of the reflected or transmitted transient continuous wave electromagnetic radiation as function of time information regarding different contributions in the transient part of the reflected or transmitted transient continuous wave electromagnetic radiation stemming from the reflections at different interfaces of the structure and determining from said information at least geometric information and/or electromagnetic properties of the one or more materials of the structure. A corresponding system also is claimed.

Abstract: A sensor for dielectric spectroscopy of a sample is disclosed. The sensor comprises a waveguide inductively loaded with a composite dielectric section which comprises a sample holder and a discontinuity separating the sample holder from the waveguide. The electromagnetic impedance of the composite dielectric section varies gradually, at least along the propagation direction of the waveguide, and at least from the onset of the discontinuity towards the sample holder.

Abstract: A sensor system for sensing a level of frozenness of a predetermined product comprises at least one emission antenna for directing electromagnetic radiation with at least one frequency within a frequency range of 0.1 GHz to 10 THz to a product and at least one receiver for receiving said electromagnetic radiation after transmission through or reflection from said product. The sensor system furthermore comprises at least one data processing unit for determining a level of frozenness based on said received electromagnetic radiation and taking into account dielectric properties of the predetermined product based on a physical-mathematical model of the product or calibration data.

Abstract: A method for determining characteristics of a layer-based structure comprises repetitively irradiating the layer-based structure with a transient continuous wave electromagnetic radiation and capturing as a function of time a transient part of the reflection or transmission of the transient continuous wave electromagnetic radiation reflected at or transmitted through the different interfaces of layer-based structure. The method furthermore comprises deriving from the transient part of the reflected or transmitted transient continuous wave electromagnetic radiation as function of time information regarding different contributions in the transient part of the reflected or transmitted transient continuous wave electromagnetic radiation stemming from the reflections at different interfaces of the layer-based structure and determining from said information at least geometric information and/or electromagnetic properties of the different layers of the layer based structure.

Abstract: A sensor for dielectric spectroscopy of a sample is disclosed. The sensor comprises a waveguide inductively loaded with a composite dielectric section which comprises a sample holder and a discontinuity separating the sample holder from the waveguide. The electromagnetic impedance of the composite dielectric section varies gradually, at least along the propagation direction of the waveguide, and at least from the onset of the discontinuity towards the sample holder.

Abstract: A device (100) is described for actively or passively modulating incident radiation, the device comprising at least one diffraction means (10) adapted for evanescent wave excitation upon irradiation with the incident radiation, and an absorption layer (40) adjacent the at least one diffraction means (10) so that the evanescent waves can interact with the absorption layer (40). The absorption layer (40) has alterable absorption properties so as to alter the absorption of the evanescent waves resulting in modulating of the incident radiation. The device (100) may be for actively modulating incident radiation thus being e.g. a modulator for laser radiation. Alternatively, the device may be for passively modulating incident radiation, thus acting as a sensing device for sensing environmental parameters.

Abstract: A device (100) is described for actively or passively modulating incident radiation, the device comprising at least one diffraction means (10) adapted for evanescent wave excitation upon irradiation with the incident radiation, and an absorption layer (40) adjacent the at least one diffraction means (10) so that the evanescent waves can interact with the absorption layer (40). The absorption layer (40) has alterable absorption properties so as to alter the absorption of the evanescent waves resulting in modulating of the incident radiation. The device (100) may be for actively modulating incident radiation thus being e.g. a modulator for laser radiation. Alternatively, the device may be for passively modulating incident radiation, thus acting as a sensing device for sensing environmental parameters.

Abstract: A laser (100) for outputting laser radiation includes a lasing material (110) in a resonant cavity (20) adapted for supporting a given lasing mode of oscillation. The laser (100) furthermore has at least one laser mirror (124) including a transparent portion for transmitting only a part of a beam of the laser (100) substantially smaller than the dimension of the beam of the laser (100) and the laser (100) includes a mode switching device (120) adapted to induce a change in the transmitted part of the beam, for altering the given lasing mode. A corresponding laser mirror (124), controller and a method for controlling a laser (100) also are described.

Abstract: A pulsed laser for machining, has a mode switch, e.g. Q-switch device (15, 30, 40), in a resonant optical cavity (20) capable of supporting a given lasing mode, e.g. a transverse mode of oscillation when lasing action is started, arranged to induce, e.g. temporarily, a localized change, e.g. loss, in the cavity. The latter alters the given lasing mode, e.g. causes the oscillation to hop to a higher transverse mode temporarily, which on its hand may be extinguished by an aperture limiting diaphragm (5) or equivalent and subsequently reduce the induced loss temporarily, to return the oscillation to the given transverse mode and output the laser pulse. A modulator can be used for inducing the temporary loss for a first transverse lasing mode and extinguishing the higher transverse mode with a diaphragm. The induced loss can be over a localized area much smaller than the dimensions of a beam of the laser, so that a miniaturized modulator can be used. In this way pulsed operation may be achieved.

Abstract: A compact polarisation selection device (99, 100, 300, 350, 500, 550) for all kind of laser beam applications is proposed. The device (99, 100, 300, 350, 500, 550) comprises at least two components (60, 70), the first component (60) having a surface (80), which is at least partly making an angle of substantially ?B,i or substantially ??B,i with respect to the first direction of the incident beam and the second component having a surface being complementary thereto. ?B,i thereby is the internal Brewster angle. As the first component (60) and the second component (70) are adapted to be offset from each other such that light leaving the surface (80) of said first component (60) is at least partly coupled into the second component (70) via said complementary shaped surface (74), selection of a polarisation component of the incident light beam is obtained. In case the surfaces are at least partly cylindrical symmetrical, at least partly radial polarised light components are obtained.

Abstract: A pulsed laser for machining, has a mode switch, e.g. Q-switch device (15, 30, 40), in a resonant optical cavity (20) capable of supporting a given lasing mode, e.g. a transverse mode of oscillation when lasing action is started, arranged to induce, e.g. temporarily, a localized change, e.g. loss, in the cavity. The latter alters the given lasing mode, e.g. causes the oscillation to hop to a higher transverse mode temporarily, which on its hand may be extinguished by an aperture limiting diaphragm (5) or equivalent and subsequently reduce the induced loss temporarily, to return the oscillation to the given transverse mode and output the laser pulse. A modulator can be used for inducing the temporary loss for a first transverse lasing mode and extinguishing the higher transverse mode with a diaphragm. The induced loss can be over a localized area much smaller than the dimensions of a beam of the laser, so that a miniaturized modulator can be used. In this way pulsed operation may be achieved.

Abstract: A method and system for detecting and monitoring a temporal and spatial distribution of a light beam are provided. A semiconductor substrate (120) having a given doping concentration range is partially exposed to an incident laser beam (150). Each part of the semiconductor structure (120) which is exposed to the laser beam is provided with an electrical contact (145), which outputs a voltage which is directly related to the optical power or energy incident on the exposed area. The thermo-voltage is produced by the laser induced thermal gradients. The sensitivity and inter-pixel cross-talk is determined by pixel pitch, doping concentration and window opening (110). Depending of the design, each pixel might be sensitive to the temporal variation of the laser beam.

Abstract: A method and system for detecting and monitoring a temporal and spatial distribution of a light beam are provided. A semiconductor substrate (120) having a given doping concentration range is partially exposed to an incident laser beam (150). Each part of the semiconductor structure (120) which is exposed to the laser beam is provided with an electrical contact (145), which outputs a voltage which is directly related to the optical power or energy incident on the exposed area. The thermo-voltage is produced by the laser induced thermal gradients. The sensitivity and inter-pixel cross-talk is determined by pixel pitch, doping concentration and window opening (110). Depending of the design, each pixel might be sensitive to the temporal variation of the laser beam.

Abstract: A method and system for detecting and monitoring a temporal and spatial distribution of a light beam are provided. A semiconductor substrate (120) having a given doping concentration range is partially exposed to an incident laser beam (150). Each part of the semiconductor structure (120) which is exposed to the laser beam is provided with an electrical contact (145), which outputs a voltage which is directly related to the optical power or energy incident on the exposed area. The thermo-voltage is produced by the laser induced thermal gradients. The sensitivity and inter-pixel cross-talk is determined by pixel pitch, doping concentration and window opening (110). Depending of the design, each pixel might be sensitive to the temporal variation of the laser beam.

Abstract: In one aspect, the present invention provides an apparatus 10 for imaging. At least one source 12 (or 12/14) of composite radiation illuminates a field of view 16. The radiation includes a set of multiple phase-independent partials that are independently controllable and exhibit distinct physical features. A quasi-optical element 21 is disposed between the field of view 16 and a multi-element receiver 18. The multi-element receiver 18 is disposed to receive image radiation 28 from the quasi-optical element 21. Particular ones of the receiver elements transform the image radiation 28 into a set of electrical signals that include information relating to features of the partials.

Abstract: A driver circuit can be used to drive a matrix display device, such as a liquid crystal display, that includes a plurality of pixels 16 disposed in rows 12 and columns 14. A first switch 328 has a current path coupled between a high voltage node (e.g., VS) and a group of pixels 16. As an example, the group of pixels 16 can be a row 12 or a column 14. A second switch 326 has a current path coupled between a low voltage node (e.g., ground) the group of pixels 16. A third switch 322 has a current path coupled between an inductive storage element 34 and the group of pixels. The inductive storage element 34 is coupled to an intermediate voltage node (e.g., VS/2) with a voltage between the voltage at the high voltage node and the voltage at the low voltage node.

Abstract: A driver circuit can be used to drive a matrix display device, such as a liquid crystal display, that includes a plurality of pixels 16 disposed in rows 12 and columns 14. A first switch 328 has a current path coupled between a high voltage node (e.g., VS) and a group of pixels 16. As an example, the group of pixels 16 can be a row 12 or a column 14. A second switch 326 has a current path coupled between a low voltage node (e.g., ground) the group of pixels 16. A third switch 322 has a current path coupled between an inductive storage element 34 and the group of pixels. The inductive storage element 34 is coupled to an intermediate voltage node (e.g., VS/2) with a voltage between the voltage at the high voltage node and the voltage at the low voltage node.

Abstract: A compact transmissive phase retarder for large and high power laser beam applications is proposed. The laser beam is orthogonally incident on the flat input surface of the optical element and is emergent from the optical component via a second flat output surface. The cross-section of the optical element is characterized by a triangularly or trapezoidally folded surface. The folded surface replaces the inclined surface of bulk equivalent elements. The functionality of the device is provided by a multi-layer interferometric structure deposited on the folded structure.

Abstract: An optical device includes a substrate 60 and three prisms 10, 20 and 30. The first prism 10 is disposed adjacent to an upper surface of the substrate 60. An incoming beam aperture 65 is positioned adjacent a first surface 12 of the first prism 10, the first surface 12 extending away from the upper surface of the substrate 60. The second prism 30 is disposed adjacent to the upper surface of the substrate 60 and is spaced from the first prism 10 by a first distance. The third prism 20 is also disposed adjacent to the upper surface of the substrate 60. The third prism 20 may be spaced from the second prism 30 by the same first distance. An outgoing beam aperture 66 is positioned adjacent a first surface 22 of the third prism 20. The substrate 60 has phase changing reflective surfaces 40 and 50 along the upper surface between the first prism 10 and the second prism 30 and between the second prism 30 and the third prism 20.