A polarization-selective diffractive optical element includes a liquid crystal polymer film supported by a substrate. The liquid crystal polymer film includes an array of pixels, each pixel encoded with a fixed liquid crystal director such that each liquid crystal director is aligned in a common plane perpendicular to the liquid crystal polymer film and provides a predetermined pattern of out-of-plane tilts. A size of the pixels in the array and the predetermined pattern are selected such that the liquid crystal polymer film forms a phase hologram for diffracting light polarized parallel to said common plane and a zeroth order diffraction grating for light polarized perpendicular to the said common plane. The non-etched and flat phase hologram is suitable for a wide range of applications.

Non-etched flat polarization-selective diffractive optical elements

A thermal control system for a liquid crystal cell is presented that may utilize a time division scheme to multiplex temperature sensing and heating functions across active thermal elements such that the cell may generally be kept at a constant temperature. A calibration process characterizes the profile of the cell and generates a polynomial regression formula that provides the voltage drive output for a temperature and cell state input. The control system stores the state of the liquid crystal cell, the regression formula, and reads the temperature of the liquid crystal cell to compute end assert the temperature compensated voltage drive.

Thermal control system for liquid crystal cell

A liquid crystal cell (100) is presented that utilizes a deposited metal gasket moisture barrier and support membrane (106) bonding two opposing plates of glass (110), a thin film spacer layer (107) to accurately control cell gap thickness, and an optional integrated thermal sensor and heater deposition layer (108) sandwiched therebetween.

Liquid crystal cell platform

One embodiment of the present invention is an exemplary wavelength selective optical coupling device. This exemplary device includes two waveguides, a ring or disc resonator, and resonator coupling elements. The waveguides are disposed on top of a substrate, not in contact with each other. The waveguides may transmit multiple wavelengths of light. The ring or disc resonator includes a dielectric member which extends parallel to the top of the substrate and overlaps, without contacting, the waveguides. The resonator is sized to resonate at a subset of resonant wavelengths. The resonator coupling elements couple the resonator to the substrate. The resonator coupling elements may include a bridge coupled to the top surface of the substrate and electrically coupled to control circuitry within the substrate. A waveguide coupling signal from the control circuitry causes the bridge to deform, translating the resonator up and down, thereby intermittently coupling and decoupling the waveguides.

Wavelength selective optical add/drop multiplexer and method of manufacture

A reconfigurable optical add-drop multiplexer is disclosed including an optical splitter receiving an input optical signal and splitting the input optical signal into a dropped optical signal and an express optical signal; a wavelength blocker optically coupled to the optical splitter, the wavelength blocker blocking particular wavelengths in the express optical signal; a cassette having a plurality of slots capable of accepting a plurality of pluggable optical filters; at least one pluggable optical filter optically coupled to the optical splitter, the pluggable optical filter filtering wavelengths so as to output a particular wavelength channel from the dropped optical signal; and an optical combiner optically coupled to the wavelength blocker and to an optical add path on which an optical add signal may be carried, the optical combiner combining the express optical signal having particular wavelengths expressed by the wavelength blocker and the optical add signal.

Reconfigurable optical add-drop multiplexer

A tunable optical wavelength selective filter comprises a dynamic holographic diffraction element (3) in combination with a fixed diffraction grating or hologram (2). The dynamic diffraction element (3) is preferably implemented as an electronically controlled image displayed on a pixelated spatial light modulator and in particular a spatial light modulating using opto-electronic integrated circuits fabricated using silicon VLSI technology and integrated with ferro-electric liquid crystals. Amongst other uses, the filter can be implemented to form a digitally tunable laser.

Wavelength selective filter

A holographic filter for an optical communication system is configurable to provide signal power equalisation for a number of optical signals or signal channels in a wavelength division multiplexed system.

Spectral equalizer using reconfigurable holographic filter

Cette invention se rapporte a un filtre holographique destine a un systeme de communication optique, susceptible d'etre configure pour assurer l'egalisation de la puissance des signaux pour une pluralite de signaux optiques ou de voies de signalisation dans un systeme a multiplexage par repartition en longueur d'onde.

Stephen Thomas Warr

Papers

Wavelength selective filter

Spectral equalizer using reconfigurable holographic filter

Egalisateur spectral utilisant un filtre holographie configurable