Abstract: The present invention provides a controllable double cladding guiding structure for tunable phase delay, dynamic chromatic dispersion and polarization mode dispersion compensation. The device includes an etched fiber, an electro-optic material with index of refraction changing with externally applied stimulus (electric, magnetic or thermal effect) and a fiber Bragg grating (uniform, apodized, linearly or non-linearly chirped).

Abstract: Described is a composite liquid crystalline mixture having a low refractive index and a chemical reactive power that makes it capable of minimizing an anchoring energy when in contact with silica. This mixture comprises: (a) low ordinary refractive index nematic liquid crystal of a single type or a mixture of low ordinary refractive index nematic liquid crystals of different types; (b) at least one reagent compound capable of reducing the anchoring energy via a chemical shielding process and from which originates a decoupling effect with a glass interface leading to the reduction of the anchoring energy and appropriately orienting a liquid crystal director at this interface; and (c) at least one low refractive index additive having a relatively low viscosity. The above mixture is useful in waveguide tuning applications.

Abstract: We propose a dynamically tunable electro-optic cladding using our proprietary electro-optic material, applied to various circular and planar wave-guides along with specific electrode configuration and excitation electric field format appropriate to that material. Based on the evanescent field coupling phenomena, the proposed device may be used in variable optical attenuators, tunable filters and couplers, etc. Different design of applied electrodes and optical properties of controllable refractive index materials allow polarization dependent or independent, as well as direct or inverse operation regimes of proposed devices.

Abstract: A variable focus liquid crystal lens includes a nematic liquid crystal/monomer mixture having a spatially inhomogenous polymer network structure, and an electrode for applying a substantially uniform voltage to the nematic liquid crystal/monomer mixture. The lens is created within a cell by applying a substantially uniform electric field to the nematic liquid crystal/monomer mixture within the cell, while simultaneously irradiating the nematic liquid crystal/monomer mixture using a laser beam having a shaped intensity distribution, so as to induce formation of a spatially inhomogenous polymer network structure within the cell.

Abstract: Broadband polarization transformation devices of various constructions are provided. The devices of the invention include a plurality of polarization switching elements that are either wavelength insensitive or used only in a wavelength insensitive manner. Preferably, 90° or 45° twisted liquid crystal cells which are electrically switchable and achromatic birefringent elements (such as Fresnel Rhombs) are used. In a particularly advantageous embodiment, the device is composed of, consecutively, a 90°TLC cell, a 45°TLC cell, a Fresnel Rhomb and an additionnal 45° TLC cell, allowing an initially linearly polarized light beam to be switched between the output polarization states p, s, &sgr;, −&sgr;, 45° and −45° depending on the application of voltages on the TLC cells.

Abstract: A method and an apparatus for coupling a light emitting diode (LED) or another light source to an optical waveguide structure via removing a section of a LED resin case to expose a surface closely proximal to a light-emitting face of the semiconductor LED chip. An input end of the optical waveguide is mounted proximal and substantially perpendicular to the surface. The optical waveguide structure and the LED resin case are bonded by, in one embodiment of the invention, a light or thermally curable resin that is applied and further solidified. In a second embodiment of the invention, a photopolymer, sensitive to the light emerging from the waveguide, is used to bond the LED resin case and the optical waveguide structure. An automated coupling system is proposed to optimize the coupling conditions using the in-coupled light efficiency feedback and controller.

Abstract: A variable optical device for selectively controlling propagation of light within an optical waveguide. The optical device comprises: a relief modulation defining a grating disposed proximal the waveguide and having a respective grating index of refraction nG; a matrix surrounding at least the relief modulation, the matrix having an index of refraction nEO that is controllable, in response to a selected stimulus between a first value that is substantially equal to the grating index of refraction nG, and a second value that is different from nG; and at least one electrode for supplying the selected stimulus to the matrix-grating system.

Abstract: The present invention provides a controllable double cladding guiding structure for tunable phase delay, dynamic chromatic dispersion and polarization mode dispersion compensation. The device includes an etched fiber, an electro-optic material with index of refraction changing with externally applied stimulus (electric, magnetic or thermal effect) and a fiber Bragg grating (uniform, apodized, linearly or non-linearly chirped).

Abstract: This invention relates to fabrication techniques for the creation of new optical elements, an asymmetric (non-reciprocal) diffraction grating and a passive nonlinear optical (visible, microwave, etc.) isolator (diode). It may have potential applications in the field of optical detection (spectrometers) and communications (circulators, wavelength division multiplexing circuits, etc.), etc. One of applications of this proposal is the significant reduction of the noise level in optical communication systems or any other optical systems using laser sources. Another potential interest of these diodes is the fabrication of integrated laser gyroscopes for applications in aviation, etc.

Abstract: A solid-state optical device supports a Helicoidal Standing Wave along an optical axis of the device. A holographic recording technique utilizes the Weigert effect to generate a spatially rotating axis of optical anisotropy in a longitudinal direction of the optical axis. As a result, a Helicoidal Standing Wave propagating in a direction of the optical axis, and having a wavelength substantially corresponding to a period of the helix, is supported by the optical device.

Abstract: We propose a dynamically tunable electro-optic cladding using our proprietary electro-optic material, applied to various circular and planar wave-guides along with specific electrode configuration and excitation electric field format appropriate to that material. Based on the evanescent field coupling phenomena, the proposed device may be used in variable optical attenuators, tunable filters and couplers, etc. Different design of applied electrodes and optical properties of controllable refractive index materials allow polarization dependent or independent, as well as direct or inverse operation regimes of proposed devices.

Abstract: A photopolymerizable composition sensitive to near infrared radiation, comprises: (i) a photopolymerizable monomer or oligomer, or a mixture thereof, capable of forming a polymer having predetermined optical properties; (ii) a photoinitiator sensitive to near infrared radiation, the photoinitiator comprising a dye sensitizer and an initiator, wherein the dye sensitizer is a cyanine dye having a perchlorate anion and the initiator is an electron donor; and (iii) a filler having optical properties selected to contrast with the optical properties of the polymer. The composition of the invention is particularly useful for producing holographic polymer dispersed liquid crystal (H-PDLC) materials and reversible dye doped polymer (RDDP) materials having improved switching characteristics.

Abstract: An optical device is produced by (a) providing an optical element; (b) providing a photopolymerizable composition comprising (i) a photopolymerizable monomer or oligomer, or a mixture thereof, capable of forming a polymer having predetermined optical properties, (ii) a photoinitiator sensitive to near infrared radiation, and (iii) a filler having optical properties selected to contrast with the optical properties of the polymer; (c) applying a layer of the photopolymerizable composition onto the optical element; and (d) exposing the optical element with the layer of photopolymerizable composition thereon to near infrared radiation to cause polymerization of the monomer or oligomer, or mixture thereof, and formation of a recording pattern on the optical element, the recording pattern comprising areas having different densities of filler in exposed and unexposed areas of the layer, thereby obtaining an optical device having thereon areas with different optical properties.

Abstract: The present invention is concerned with photopolymer materials sensitive to infrared, near infrared, red and green light radiation for initiating polymerization and to applications of such photopolymer, like holographic polymer dispersed liquid crystal (H-PDLC) or reversible dye doped photopolymer (RDDP) materials, for making optical devices. The invention relates to holographic polymer dispersed liquid crystal and reversible dye materials having improved electrical and optical switching properties.

Abstract: This invention relates to fabrication techniques for the creation of new optical elements, an asymmetric (non-reciprocal) diffraction grating and a passive nonlinear optical (visible, microwave, etc.) isolator (diode). It may have potential applications in the field of optical detection (spectrometers) and communications (circulators, wavelength division multiplexing circuits, etc.), etc. One of applications of this proposal is the significant reduction of the noise level in optical communication systems or any other optical systems using laser sources. Another potential interest of these diodes is the fabrication of integrated laser gyroscopes for applications in aviation, etc.

Abstract: By adjusting a state of circular polarization of a laser beam, a rate of rotation in micro objects rotated by angular momentum imparted from the light is controlled. The light has greatest effect on anisotropic transparent micro objects. A micro mixer using anisotropic micro probe objects can also be provided by using the light to control rotation of the probe objects in a suspension or solution.