Abstract: A non-coherent light emitting device having at least one organic light emitting or organic charge transporting layer and a structure providing a Bragg grating associated with the light emitting layer is described. The organic light emitting layer having liquid crystalline material is treated to provide alternating zones of isotropic and liquid crystalline material. The combination of alternating zones with the dichroic effects of the aligned zone produces a pseudo 2-D Bragg grating within the light emitting layer.

Abstract: A tunable narrow linewidth laser is provided, wherein an adjustable etalon structure is employed to simultaneously tune the wavelength of the laser transmission and the length of the laser cavity. The etalon structure is an effective, relatively thick shear plate comprised of transparent matched wedge-shaped substrates and a pair of parallel, partially transmissive mirrors with a space therebetween. Rotation of the etalon structure relative to the laser input changes the angle of incidence to the first substrate and the etalon angle, thereby changing the wavelength of the laser light and also changing the length of the external laser cavity. Thus, reliable frequency tuning is achieved, without mode hopping.

Abstract: A non-coherent light emitting device having at least one organic light emitting or organic charge transporting layer and a structure providing a Bragg grating associated with the light emitting layer is described. The organic light emitting layer having liquid crystalline material is treated to provide alternating zones of isotropic and liquid crystalline material. The combination of alternating zones with the dichroic effects of the aligned zone produces a pseudo 2-D Bragg grating within the light emitting layer.

Abstract: A tunable narrow linewidth laser is provided, wherein an adjustable etalon structure is employed to simultaneously tune the wavelength of the laser transmission and the length of the laser cavity. The etalon structure is an effective, relatively thick shear plate comprised of transparent matched wedge-shaped substrates and a pair of parallel, partially transmissive mirrors with a space therebetween. Rotation of the etalon structure relative to the laser input changes the angle of incidence to the first substrate and the etalon angle, thereby changing the wavelength of the laser light and also changing the length of the external laser cavity. Thus, reliable frequency tuning is achieved, without mode hopping.

Abstract: A display light source (230) includes a gain media (232), an output reflector (246), and a wavelength converter (244) that cooperate to generate a source output beam (260). The gain media (232) generates a media output beam (247) that exits an output facet (232B) of the gain media (232). The media output beam (247) has a first spectral frequency range and a relatively large number of modes. The output reflector (246) is spaced apart from the gain media (232), and the output reflector (246) forms a portion of a laser cavity (251). The wavelength converter (244) is positioned within the laser cavity (251). The wavelength converter (244) converts at least a portion of the media output beam (247) from the first spectral frequency range to a converted beam (258) having at a secondary spectral frequency range. For example, the wavelength converter (244) can double the frequency of the media output beam (247).

Abstract: A light source system comprises a light source disposed within a non-imaging optical element. The non-imaging optical element does not produce a direct image of the light source, and the output light field at the output surface of the non-imaging optical element has an intensity that is substantially uniform over the area of the output surface. A light source system of the invention is therefore smaller and lighter than a prior art system of the same output power, since there is no need to provide further components, such as an integrator, to homogenise the output light field.

Abstract: A laser apparatus for nonlinear conversion of light is disclosed utilizing a laser diode having a reflective back facet and a front facet having a reflectance of less than about 1% for emitting a multifrequency optical beam, and a nonlinear optical element for receiving the multifrequency optical beam and for generating a frequency-converted radiation. An external frequency-selective reflector is provided for power and spectral stabilization of the multifrequency optical beam, and for confining its optical spectrum within a bandwidth of efficient nonlinear conversion in the nonlinear optical element. The laser diode reflective back facet and the external frequency-selective reflector form an extended laser cavity. In operation, the multifrequency optical beam contains a plurality of longitudinal modes of the extended laser cavity which are confined within the frequency conversion bandwidth of the nonlinear element.

Abstract: An apparatus is described for controlling the optical path length in an optical device, e.g. an interferometer, and more importantly to maintaining the optical path length difference in an interferometer. The apparatus may include an adjustable plate optically coupled with a beamsplitter. The plate may be rotated such that its surface receives light propagated from the beamsplitter at a non-zero incident angle. In one embodiment, temperature sensitivity is addressed by ensuring that the refractive index of the plate is greater than the refractive index of the beamsplitter. In another embodiment, the apparatus includes combination spacers having a component selected in dependence upon a composition, thickness, and orientation of the adjustable plate.

Abstract: A laser apparatus for nonlinear conversion of light is disclosed utilizing a laser diode having a reflective back facet and a front facet having a reflectance of less than about 1% for emitting a multifrequency optical beam, and a nonlinear optical element for receiving the multifrequency optical beam and for generating a frequency-converted radiation. An external frequency-selective reflector is provided for power and spectral stabilization of the multifrequency optical beam, and for confining its optical spectrum within a bandwidth of efficient nonlinear conversion in the nonlinear optical element. The laser diode reflective back facet and the external frequency-selective reflector form an extended laser cavity. In operation, the multifrequency optical beam contains a plurality of longitudinal modes of the extended laser cavity which are confined within the frequency conversion bandwidth of the nonlinear element.

Abstract: The present invention relates to an interferometer useful in the interleaving and de-interleaving of optical wavelength channels. Typically the invention comprises a beamsplitter and two resonators, e.g. GT etalons or ring resonators. The beamsplitter splits an input beam of light into a first sub-beam directed to follow a first path and a second sub-beam directed to follow a second path. The first resonator has a first effective cavity length and receives the first sub-beam. The second resonator has a second effective cavity length and receives the second sub-beam. The first path and the second path have an effective optical path difference approximately equal to one-half the first effective cavity length. In one embodiment, the front plates of the GT etalons each have a different reflectivity, and are selected to provide a desired spectral response.

Abstract: An optical performance monitor having a tunable fiber grating sandwiched between the first and second reflective surfaces of a fiber etalon provides high sensitivity, while simultaneously monitoring an optical data signal. Individual channels within the optical data signal are monitored by tuning the fiber grating over the wavelength range of the optical data signal to measure an intensity of each channel. As the tunable grating scans the wavelength range of interest, it simultaneously changes the resonant cavity length of the etalon, thus allowing the etalon to effectively monitor the tunable grating with a wavelength outside the wavelength range of the optical data signal.

Abstract: A method and device for providing tunable dispersion compensation by splitting an incoming optical beam and then recombining interferometrically two sub-beams which have been passed through fixed dispersive (dispersion producing) elements. The polarization of the incoming optical signal is controlled and the signal beam is split into sub-beams at a ratio dependent on the polarization. The sub-beams are directed to each of two interferometer arms. The return beams are interfered e.g. by placing a quarter waveplate at 45° to the two orthogonal polarization axes. This produces a near-lossless beam with a tunable amount of dispersion dependent on the ratio of beam split.

Abstract: A 1½×2 optical switch has two GRIN lenses, each lens having two ports on its respective outward end face. The switch has a transmissive wedge-shaped switching element disposed between the GRIN lenses. When the switching element is disposed in the path between the GRIN lenses, a single connection is established between a port of the first GRIN lens and a port of the second GRIN lens, while light is prevented from coupling between the remaining ports.

Abstract: The present invention relates to an interferometer useful in the interleaving and de-interleaving of optical wavelength channels. Typically the invention comprises a beamsplitter and two resonators, e.g. GT etalons or ring resonators. The beamsplitter splits an input beam of light into a first sub-beam directed to follow a first path and a second sub-beam directed to follow a second path. The first resonator has a first effective cavity length and receives the first sub-beam. The second resonator has a second effective cavity length and receives the second sub-beam. The first path and the second path have an effective optical path difference approximately equal to one-half the first effective cavity length. In one embodiment, the front plates of the GT etalons each have a different reflectivity, and are selected to provide a desired spectral response.

Abstract: An optical performance monitor having a tunable fiber grating sandwiched between the first and second reflective surfaces of a fiber etalon provides high sensitivity, while simultaneously monitoring an optical data signal. Individual channels within the optical data signal are monitored by tuning the fiber grating over the wavelength range of the optical data signal to measure an intensity of each channel. As the tunable grating scans the wavelength range of interest, it simultaneously changes the resonant cavity length of the etalon, thus allowing the etalon to effectively monitor the tunable grating with a wavelength outside the wavelength range of the optical data signal.

Abstract: An apparatus is described for controlling the optical path length in an optical device, e.g. an interferometer, and more importantly to maintaining the optical path length difference in an interferometer. The apparatus may include an adjustable plate optically coupled with a beamsplitter. The plate may be rotated such that its surface receives light propagated from the beamsplitter at a non-zero incident angle. In one embodiment, temperature sensitivity is addressed by ensuring that the refractive index of the plate is greater than the refractive index of the beamsplitter. In another embodiment, the apparatus includes combination spacers having a component selected in dependence upon a composition, thickness, and orientation of the adjustable plate.

Abstract: An optical switch is disclosed having 4-ports. The switch consists of a first GRIN lens having 2 ports adjacent its outwardly facing end face. A second GRIN lens is disposed to receive light from the first GRIN lens and has two ports adjacent its outer end face. In a first state, a first port from the first GRIN lens couples light with a first output port of the second GRIN lens. In a second state, a movable optical element in the form of a light transmissive wedge having a reflective surface, is disposed in the path between first and second GRIN lens, providing a connection between a port of the first GRIN lens and a second port of the second GRIN lens. In a third connect state, the reflective surface of the wedge connects a port of the first GRIN lens and an output port in the same first GRIN lens. Hence an N×M optical switch is disclosed.

Abstract: A method and circuit is disclosed wherein two waveguides coupled to an optical resonator are further coupled such that beams propagating therein interfere with one another to provide a desired output response. In one embodiment, multiplexed channels of light can be demultiplexed by the device described heretofore, or alternatively, the phase relationship between these two beams can be altered prior to their being combined to provide, for example, a linearized output response useful in applications such as wavelength locking.

Abstract: A system and method for determining noise power levels across a range of frequencies of the optical signal output from a device operating at a specified optical power and drive current and, in particular, for determining relative intensity noise values (RIN). The system may comprise a reference laser for generating an optical reference signal and a photodetector for converting the optical signal output from the reference laser and the device under test into equivalent electrical signals. The system also comprises means for measuring ac and dc components of the electrical signals output from the photodetector. The system may be used to measure RIN levels to an accuracy of less than 1 dB. Such measurements are of particular importance in the field of fiber optic telecommunications. The reference laser is shot noise limited in the frequency range of interest, typically between 20 MHz and 20 GHz, and has a narrow linewidth, typically less than 5 kHz.

Abstract: A method and circuit is disclosed wherein two waveguides coupled to an optical resonant ring resonator are further coupled such that beams propagating therein interfere with one another to provide a desired output response. In one embodiment, multiplexed channels of light can be demultiplexed by the device described heretofore, or alternatively, the phase relationship between these two beams can be altered prior to their being combined to provide, for example, a linearized output response useful in applications such as wavelength locking. By varying the reflectivity of the FSR and the coupling ratios and/or by varying the phase relationship between the two beams, a variety of desired output responses can be realized.