Abstract: A diode-pumped solid state laser system and a method of diode-pumping a solid state laser in which the emitter beamlets in the diode bar are directed at a beam transformation optical element which includes a continuous twisted surface to produce a uniform and symmetrised beam in the fast field which is then focused to match an input pump area of the gain medium of the solid state laser. Embodiments to square and rectangular flat-top intensity distributions are described using a Fourier lens and a set of cylindrical orthogonal lenses.

Abstract: An optical beam shaping element to perform beam shaping of multi-mode laser beams where a uniform ring-shaped intensity distribution is produced at a focal length of a focusing lens. The optical beam shaping element with a surface having radial arms which are twisted to be curved in comparison to a known Siemens star beam shaper giving a spiral configuration. Embodiments are described in which each of the arms in the spiral structure is additionally modified with radially varied slope and/or curvature to optimise far field distribution. Relative rotation between two optical beam shaping elements forms an adjustable trident to vary power between the ring and a centre spot. The optical beam shaping element finds application in laser material processing were the spiral curvature removes hotspots and can be configured to improve through focus performance and input sensitivity.

Abstract: A diode-pumped solid state laser system and a method of diode-pumping a solid state laser in which the emitter beamlets in the diode bar are directed at a beam transformation optical element which includes a continuous twisted surface to produce a uniform and symmetrised beam in the fast field which is then focused to match an input pump area of the gain medium of the solid state laser. Embodiments to square and rectangular flat-top intensity distributions are described using a Fourier lens and a set of cylindrical orthogonal lenses.

Abstract: A field mapping optical system and method for converting a light beam having a known spatially coherent first optical field to a second optical field with a required intensity distribution and flat wavefront at a desired distance from the system, by creating an intermediate optical field, between the first and second optical fields, the intermediate optical field being derived from the inverse Fourier transform of the second optical field. The optical system provides a compact and simplified field mapper.

Abstract: A process for the manufacture of custom freeform optical elements utilising parameterised modelling. A system for the automatic manufacture of a custom optical element is also described with the manufacturing being by laser micro-machining. The process and system allow customers to specify and order via a web interface and so reduce engineering time, overhead and cost.

Abstract: A process for the manufacture of custom freeform optical elements utilising parameterised modelling. A system for the automatic manufacture of a custom optical element is also described with the manufacturing being by laser micro-machining. The process and system allow customers to specify and order via a web interface and so reduce engineering time, overhead and cost.

Abstract: A process for the manufacture of custom freeform optical elements utilizing parameterized modelling. A system for the automatic manufacture of a custom optical element is also described with the manufacturing being by laser micro-machining. The process and system allow customers to specify and order via a web interface and so reduce engineering time, overhead and cost.

Abstract: A field mapping optical system and method for converting a light beam having a known spatially coherent first optical field to a second optical field with a required intensity distribution and flat wavefront at a desired distance from the system, by creating an intermediate optical field, between the first and second optical fields, the intermediate optical field being derived from the inverse Fourier transform of the second optical field. The optical system provides a compact and simplified field mapper.

Abstract: A method and apparatus of generating a laser pulse of a desired energy and micro-machining a substrate using the laser pulse. A beam of light is provided from a laser source. The beam is directed via a modulator to produce an output laser pulse with a portion of the laser pulse being used to determine the energy of the laser pulse. The modulator is controlled so as to switch off the output laser pulse when the determined energy of the output laser pulse reaches a threshold value. The output laser pulse is steered to a substrate for micro-machining.

Abstract: A multi-wavelength laser array of a plurality of emitters in a diode bar or stack where each beam is deflected by a different angle to be incident upon a uniform volume holographic grating with a portion of the beam being deflected as a feedback portion while a further portion provides a wavelength tuned output unique to each emitter. The arrangement of a uniform volume holographic grating with deflectors such as phaseplates eliminates the need to use expensive wavelength chirped gratings.

Abstract: A process for the manufacture of custom freeform optical elements utilising parameterized modelling. A system for the automatic manufacture of a custom optical element is also described with the manufacturing being by laser micro-machining. The process and system allow customers to specify and order via a web interface and so reduce engineering time, overhead and cost.

Abstract: A micro-optical element for use with an edge-emitting laser diode bar stack, the element comprising a plurality of spaced apart fast-axis collimators formed as a monolithic array, wherein the spacing between the collimators in the fast-axis varies across the micro-optic element. A method of manufacturing a micro-optical element for use with a laser diode bar stack, using a wavelength stabilized CO2 laser is also described.

Abstract: A multi-wavelength laser array of a plurality of emitters in a diode bar or stack where each beam is deflected by a different angle to be incident upon a uniform volume holographic grating with a portion of the beam being deflected as a feedback portion while a further portion provides a wavelength tuned output unique to each emitter. The arrangement of a uniform volume holographic grating with deflectors such as phaseplates eliminates the need to use expensive wavelength chirped gratings.

Abstract: A method and apparatus of generating a laser pulse of a desired energy and micro-machining a substrate using the laser pulse. A beam of light is provided from a laser source. The beam is directed via a modulator to produce an output laser pulse with a portion of the laser pulse being used to determine the energy of the laser pulse. The modulator is controlled so as to switch off the output laser pulse when the determined energy of the output laser pulse reaches a threshold value. The output laser pulse is steered to a substrate for micro-machining.

Abstract: A system for measuring the wavefront characteristics of a powerful laser close to an emitting or transmitting surface of the laser. The system includes a beam sampler that has a sampling aperture for sampling radiation from a sampled area along the emitting or transmitting surface. The beam sampler includes a reflector for directing un-sampled radiation onto an absorber, which absorbs un-sampled radiation. Radiation sampled by the beam sampler is sensed using a sensor.

Abstract: A micro-optical element for use with an edge-emitting laser diode bar stack, the element comprising a plurality of spaced apart fast-axis collimators formed as a monolithic array, wherein the spacing between the collimators in the fast-axis varies across the micro-optic element. A method of manufacturing a micro-optical element for use with a laser diode bar stack, using a wavelength stabilized CO2 laser is also described.

Abstract: A system for measuring the wavefront characteristics of a powerful laser close to an emitting or transmitting surface of the laser. The system includes a beam sampler that has a sampling aperture for sampling radiation from a sampled area along the emitting or transmitting surface. The beam sampler includes a reflector for directing un-sampled radiation onto an absorber, which absorbs un-sampled radiation. Radiation sampled by the beam sampler is sensed using a sensor.

Abstract: An optical fibre bend sensor (10) measures the degree and orientation of bending present in a sensor length (30) portion of a fibre assembly (26). Within a multicored fibre (30, 32,34), cores (62, 66) are grouped in non-coplanar pairs. An arrangement of optical elements (28, 36, 38) define within each core pair (62, 66) two optical paths (122, 124) which differ along the sensor length (30): one core (62) of a pair (62, 66) is included in the first path (122), and the other core (66) in the second path (124). A general bending of the sensor region (30) will lengthen one core (62, 66) with respect to the other. Interrogation of this length differential by means of interferometry generates interferograms from which the degree of bending in the plane of the core pair is extracted. Bend orientation can be deduced from data extracted from multiple core pairs.

Abstract: An optical fiber bend sensor (10) measures the degree and orientation of bending present in a sensor length (30) portion of a fiber assembly (26). Within a multicored fiber (30, 32,34), cores (62, 66) are grouped in non-coplanar pairs. An arrangement of optical elements (28, 36, 38) define within each core pair (62, 66) two optical paths (122, 124) which differ along the sensor length (30): one core (62) of a pair (62, 66) is included in the first path (122), and the other core (66) in the second path (124). A general bending of the sensor region (30) will lengthen one core (62, 66) with respect to the other. Interrogation of this length differential by means of interferometry generates interferograms from which the degree of bending in the plane of the core pair is extracted. Bend orientation can be deduced from data extracted from multiple core pairs.

Abstract: An optical fiber bend sensor (10) measures the degree and orientation of bending present in a sensor length (30) portion of a fiber assembly (26). Within a multicored fiber (30, 32, 34), cores (62, 66) are grouped in non-coplanar pairs. An arrangement of optical elements (28, 36, 38) define within each core pair (62, 66) two optical paths (122, 124) which differ along the sensor length (30): one core (62) of a pair (62, 66) is included in the first path (122), and the other core (66) in the second path (124). A general bending of the sensor region (30) will lengthen one core (62, 66) with respect to the other. Interrogation of this length differential by means of interferometry generates interferograms from which the degree of bending in the plane of the core pair is extracted. Bend orientation can be deduced from data extracted from multiple core pairs.