Abstract: An optical multiplexer (10) that multiplexes a plurality of light beams having different wavelengths includes a first waveguide (101) that receives first-wavelength light, a second waveguide (102) that receives second-wavelength light having a shorter wavelength than the first-wavelength light, a third waveguide (103) that receives third-wavelength light having a shorter wavelength than the second-wavelength light, a first multiplexer (110) in which the light propagates between the first waveguide (101) and the second waveguide (102), and a second multiplexer (120) in which the light propagates between the first waveguide (101) and the third waveguide (103). The second-wavelength light is propagated to the first waveguide (101) at the first multiplexer (110). The third-wavelength light is propagated to the first waveguide (101) at the second multiplexer (120).

Abstract: A gas analyzer and related methods are for measuring a concentration of a component of a gas mixture. The gas analyzer includes a gas cell defining an overall volume for housing the gas mixture, a gas inlet and a gas outlet, a light source that emits a light beam into the gas cell, and a light detector that detects a portion of the light of the light beam that has propagated through the gas mixture, the concentration of the component of the gas mixture being determined based on the portion of the light beam detected by the light detector. The gas cell defines an optical volume for travel of the light beam within the gas cell, and the optical volume comprises at least a portion of the overall volume and is configured to suppress turbulent flow of the gas mixture within the optical volume to reduce optical noise generated by the gas mixture.

Abstract: A light beam separating and absorbing element includes a mirror that receives first and second light beams incident on a first surface, and the mirror is configured to transmit the first light beam and reflect the second light beam. A beam absorber receives the first light beam transmitted through the mirror, and absorbs a first light portion of the transmitted first light beam after the first light beam has been transmitted through the mirror. The beam absorber scatters a second portion of the first light beam, and the beam absorber and mirror are positioned such that at least a portion of the scattered light is incident on a second surface of the mirror. Transmissivity of the mirror for the scattered light incident on the second mirror surface may be lower as compared to transmissivity for the first light beam incident on the first mirror surface to enhance separation of the first and second light beams.

Abstract: A laser device includes a light source that emits a source light having a first peak wavelength. A nonlinear optical component performs a frequency conversion process that converts the source light into output light having a second peak wavelength. A stabilization component minimizes a mismatch error constituting a difference between the first peak wavelength and a wavelength for which the frequency conversion process in the nonlinear optical component has a maximum value. The stabilization component may include a housing that is thermally conductive between the light source and the nonlinear optical component to minimize a temperature difference between the light source and the nonlinear optical component. The laser device may include a focusing optical component that focuses the source light to have a convergence half angle that is larger than a convergence half angle that gives maximum output power, thereby increasing an acceptable range of the mismatch error.

Abstract: A wavelength separating element is provided for separating a converted beam from a fundamental beam in an NLFC device, wherein the converted beam has a wavelength different from a wavelength of the fundamental beam. The wavelength separating element includes a first mirror surface and a second mirror surface opposite to the first mirror surface. The first and second mirror surfaces may have a high reflectivity of the converted beam relative to a reflectivity of the fundamental beam, and the first and second mirror surfaces are configured such that the fundamental and converted beams undergo multiple reflections between the first mirror surface and the second mirror surface to separate the converted beam from the fundamental beam. The fundamental and converted beams undergo at least three reflections at the first and second mirror surfaces, and/or undergo at least two reflections at one of the first mirror surface or the second mirror surface.

Abstract: A light beam separating and absorbing element includes a mirror that receives first and second light beams incident on a first surface, and the mirror is configured to transmit the first light beam and reflect the second light beam. A beam absorber receives the first light beam transmitted through the mirror, and absorbs a first light portion of the transmitted first light beam after the first light beam has been transmitted through the mirror. The beam absorber scatters a second portion of the first light beam, and the beam absorber and mirror are positioned such that at least a portion of the scattered light is incident on a second surface of the mirror. Transmissivity of the mirror for the scattered light incident on the second mirror surface may be lower as compared to transmissivity for the first light beam incident on the first mirror surface to enhance separation of the first and second light beams.

Abstract: A laser device includes a light source that emits a source light having a first peak wavelength. A nonlinear optical component performs a frequency conversion process that converts the source light into output light having a second peak wavelength. A stabilization component minimizes a mismatch error constituting a difference between the first peak wavelength and a wavelength for which the frequency conversion process in the nonlinear optical component has a maximum value. The stabilization component may include a housing that is thermally conductive between the light source and the nonlinear optical component to minimize a temperature difference between the light source and the nonlinear optical component. The laser device may include a focusing optical component that focuses the source light to have a convergence half angle that is larger than a convergence half angle that gives maximum output power, thereby increasing an acceptable range of the mismatch error.

Abstract: A laser device includes a light source that emits a source light having a first peak wavelength. A nonlinear optical component performs a frequency conversion process that converts the source light into output light having a second peak wavelength. A stabilization component minimizes a mismatch error constituting a difference between the first peak wavelength and a wavelength for which the frequency conversion process in the nonlinear optical component has a maximum value. The stabilization component may include a housing that is thermally conductive between the light source and the nonlinear optical component to minimize a temperature difference between the light source and the nonlinear optical component. The laser device may include a focusing optical component that focuses the source light to have a convergence half angle that is larger than a convergence half angle that gives maximum output power, thereby increasing an acceptable range of the mismatch error.

Abstract: A wavelength separating element is provided for separating a converted beam from a fundamental beam in an NLFC device, wherein the converted beam has a wavelength different from a wavelength of the fundamental beam. The wavelength separating element includes a first mirror surface and a second mirror surface opposite to the first mirror surface. The first and second mirror surfaces may have a high reflectivity of the converted beam relative to a reflectivity of the fundamental beam, and the first and second mirror surfaces are configured such that the fundamental and converted beams undergo multiple reflections between the first mirror surface and the second mirror surface to separate the converted beam from the fundamental beam. The fundamental and converted beams undergo at least three reflections at the first and second mirror surfaces, and/or undergo at least two reflections at one of the first mirror surface or the second mirror surface.

Abstract: A ballistic carrier spectral sensor includes a photon absorption region to generate photo-generated carriers from incident light; a first potential barrier region adjacent the photon absorption region and having an adjustable height defining a minimum energy of the photo-generated carriers required to pass therethrough; a second potential barrier region having an adjustable height defining a minimum energy of the photo-generated carriers required to pass therethrough; a spillage well region disposed between the first potential barrier region and the second potential barrier region and configured to collect photo-generated carriers having an energy lower than that required to pass through the second potential barrier region; and a collection region adjacent the second potential barrier region and configured to collect carriers that cross the second potential barrier region.

Abstract: A group III nitride-based light emitting device includes an n-type group III nitride-based semiconductor layer, a p-type group III nitride-based semiconductor layer, and a group III nitride-based active region between the p-type semiconductor layer and the n-type semiconductor layer. The active region includes a plurality of sequentially stacked group III nitride-based quantum well layers interspersed with barrier layers. A plurality of the barrier layers have a variation in composition of a first element along a growth direction within a thickness of each of the plurality of barrier layers, and the variation in composition of the first element has at least one minimum and a position of the minimum varies in the plurality of barrier layers. The first element may be indium or aluminum, and the number of barrier layers including the composition variation may be at least three barrier layers. The composition variation may vary linearly or non-linearly.

Abstract: A group III nitride-based light emitting device includes an n-type group III nitride-based semiconductor layer, a p-type group III nitride-based semiconductor layer, and a group III nitride-based active region between the p-type semiconductor layer and the n-type semiconductor layer. The active region includes a plurality of sequentially stacked group III nitride-based quantum well layers interspersed with barrier layers. A plurality of the barrier layers have a variation in composition of a first element along a growth direction within a thickness of each of the plurality of barrier layers, and the variation in composition of the first element has at least one minimum and a position of the minimum varies in the plurality of barrier layers. The first element may be indium or aluminium, and the number of barrier layers including the composition variation may be at least three barrier layers. The composition variation may vary linearly or non-linearly.

Abstract: A light emitting diode (LED) is provided that includes a host substrate formed from a first material, an n-type layer formed over the host substrate, an active region formed over the n-type layer, and a p-type layer formed over the active region. A layer is formed adjacent to the host substrate and includes a second material, the second material being different from the first material or having a refractive index different from a refractive index of the first material. Further, the second material is formed with a tapered outwards sidewall profile.

Abstract: A light emitting diode is provided which includes an active region in combination with a current spreading layer; and a crystalline epitaxial film light extraction layer in contact with the current spreading layer, the light extraction layer being patterned with nano/micro structures which increase extraction of light emitted from the active region.

Abstract: A light emitting diode (LED) is provided along with a method of making the same. The LED includes a conductive n-type region formed on a substrate; an active region formed on the n-type region; a first p-type region formed on the active region; a plurality of nanostructures formed on the first p-type region to carry out light extraction from the active region, the nanostructures having a diameter less than 500 nm; a second p-type region regrown on the first p-type region to form a non-planar surface in combination with the nanostructures; and a p-type electrode formed on the non-planar surface.

Abstract: A light emitting diode device which includes at least one light emitting diode, a heat-sink chassis having a surface upon which the at least one light emitting diode is mounted, and a waveguide having one end coupled to the at least one light emitting diode for receiving light therefrom. The waveguide has another end which includes a light extraction and redistribution region, and the waveguide is configured to guide light received from the at least one light emitting diode away from the heat-sink chassis and towards the light extraction and redistribution region. The light extraction and redistribution region is configured to extract and redistribute the light from the waveguide.

Abstract: A method for growing an In(x)Al(y)Ga(1?x?y)N layer (where x is greater than zero and less than or equal to one, y is greater than or equal to zero and less than or equal to one and the sum of x and y is less than or equal to one). The method includes supplying plasma-activated nitrogen atoms as a source of nitrogen for the In(x)Al(y)Ga(1?x?y)N layer to a growth surface, where a flux of the plasma-activated nitrogen atoms supplied to the growth surface is at least four times higher than a total flux of aluminium and gallium atoms also supplied to the growth surface, where either the aluminium or gallium flux may or may not be zero; and simultaneously supplying indium atoms and nitrogen-containing molecules to the growth surface.

Abstract: A light emitting diode (LED) is provided along with a method of making the same. The LED includes a conductive n-type region formed on a substrate; an active region formed on the n-type region; a first p-type region formed on the active region; a plurality of nanostructures formed on the first p-type region to carry out light extraction from the active region, the nanostructures having a diameter less than 500 nm; a second p-type region regrown on the first p-type region to form a non-planar surface in combination with the nanostructures; and a p-type electrode formed on the non-planar surface.

Abstract: A laminated substrate system containing a metamorphic transition region (2) made from multiple and alternating layers of AlxGa1-xN (5) and the supporting substrate material (4) (or a material having the same general chemical composition thereto). A III-Nitrides semiconductor device (2) with a low dislocation density is formed on top of the laminated substrate system. The multiple layers (4,5) of the metamorphic transition region form a superlattice structure whose lattice constant and structure changes along its growth direction from that of the supporting substrate (1) (in the vicinity of the supporting substrate) to that of the device (3) (in the vicinity of the device).

Abstract: A semiconductor light-emitting device comprises a semiconductor layer structure disposed over a substrate. The layer structure includes an active region disposed between a first layer and a second layer. One or more cavities are present in the layer structure, each cavity being coincident with a threading dislocation and extending from an upper surface of the layer structure through at least the second layer and the active region. Removing material where a threading dislocation is present provides effective suppression of the tendency of the threading dislocations to act as non-radiative centres, thereby improving the light output efficiency of the device. The device may be manufactured by a first step of selectively etching the layer structure at the locations of one or more threading dislocation to form a pilot cavity at the or each location. A second etching step is applied to increase the depth of each pilot cavity.