Abstract: An optical switch that includes optical paths organized into a set of M input optical paths and a set of N output optical paths, where at least one of M and N is greater than unity. The optical switch additionally includes a faceted mirror corresponding to each of the M input optical paths and including N facets and a faceted mirror corresponding to each of the N output optical paths and including M facets. Finally, the optical switch includes a moving mechanism coupled to each faceted mirror to step the faceted mirror linearly in a direction orthogonal to the optical paths to selectively align one of the facets of the faceted mirror with the one of the optical paths with which the faceted mirror is associated. The facets of each of the faceted mirror corresponding to one of the sets of optical paths, i.e.

Abstract: The multi-channel optical transmitter is composed of a tunable optical signal source, an optical multiplexer and an intensity reducer. The tunable optical signal source includes a tunable laser, and additionally includes an optical signal output through which it outputs an optical signal to one of the inputs of the optical multiplexer. The intensity reducer is for reducing the intensity of the optical signal output by the optical signal source during tuning of the tunable laser. The intensity reducer prevents the tunable optical signal source from injecting high levels of noise into the channels during tuning of the tunable optical signal source.

Abstract: A method and a system for displaying images are provided. In the method, a pixel is provided that includes a layer of ferroelectric material and a layer of liquid crystal material. A first electric field is momentarily applied to the pixel to electrically polarize the ferroelectric layer to a first polarization. The first polarization is then used to maintain the liquid crystal material in a first orientation corresponding to a first apparent brightness of the pixel.

Abstract: The optical fiber tap establishes optical communication between a branch optical fiber and a main optical fiber and includes a housing, a serpentine main channel and a branch channel. The main channel is defined in the housing and is shaped to accommodate part of the main optical fiber. The main channel includes a coupling curve portion shaped to define a main coupling curve in the main optical fiber. The branch channel is also defined in the housing and is shaped to accommodate part of the branch optical fiber. The branch channel communicates with the main channel at the coupling curve portion of the main channel. Optical signals couple laterally between the main optical fiber located in the main channel and the branch optical fiber located in the branch channel. Optical communication between the optical fibers is therefore established.

Abstract: The optical splitter includes a diffractive optical element (DOE) to create a generally two-dimensional array of beams of light from an input light beam. Each beam carries substantially identical information content. The intensity and the position of each element of the array of beams may be controlled. In addition, an embodiment of the invention is an optical demultiplexer that comprises the above optical splitter.

Abstract: The tunable optical filter includes an elastic substrate, a diffractive element in the elastic substrate, an actuator for stretching the elastic substrate to control the pitch of the diffractive element, a first optical path and a second optical path. The diffractive element optically couples the second optical path to the first optical path at an optical frequency determined by the pitch of the diffractive element.

Abstract: An optical switch that includes optical paths organized into a set of M input optical paths and a set of N output optical paths. The optical switch additionally includes a faceted mirror corresponding to each of the M input optical paths and including N facets and a faceted mirror corresponding to each of the N output optical paths and including M facets. Finally, the optical switch includes a moving mechanism coupled to each faceted mirror to step the faceted mirror to selectively align one of the facets of the faceted mirror with the one of the optical paths with which the faceted mirror is associated. The facets of each of the faceted mirrors corresponding to one of the sets of optical paths, i.e., the set of input optical paths or the set of output optical paths, are preferably angled to reflect light towards a different one of the faceted mirrors corresponding to the other of the sets of optical paths, i.e., the set of output optical paths or the set of input optical paths, respectively.

Abstract: The optical fiber tap establishes optical communication between a branch optical fiber and a main optical fiber and includes a housing, a serpentine main channel and a branch channel. The main channel is defined in the housing and is shaped to accommodate part of the main optical fiber. The main channel includes a coupling curve portion shaped to define a main coupling curve in the main optical fiber. The branch channel is also defined in the housing and is shaped to accommodate part of the branch optical fiber. The branch channel communicates with the main channel at the coupling curve portion of the main channel. Optical signals couple laterally between the main optical fiber located in the main channel and the branch optical fiber located in the branch channel. Optical communication between the optical fibers is therefore established.

Abstract: An optical switch that includes optical paths organized into a set of M input optical paths and a set of N output optical paths. The optical switch additionally includes a faceted mirror corresponding to each of the M input optical paths and including N facets and a faceted mirror corresponding to each of the N output optical paths and including M facets. Finally, the optical switch includes a moving mechanism coupled to each faceted mirror to step the faceted mirror to selectively align one of the facets of the faceted mirror with the one of the optical paths with which the faceted mirror is associated. The facets of each of the faceted mirrors corresponding to one of the sets of optical paths, i.e., the set of input optical paths or the set of output optical paths, are preferably angled to reflect light towards a different one of the faceted mirrors corresponding to the other of the sets of optical paths, i.e., the set of output optical paths or the set of input optical paths, respectively.

Abstract: An optical switch that includes optical paths organized into a set of M input optical paths and a set of N output optical paths. The optical switch additionally includes a faceted mirror corresponding to each of the M input optical paths and including N facets and a faceted mirror corresponding to each of the N output optical paths and including M facets. Finally, the optical switch includes a moving mechanism coupled to each faceted mirror to step the faceted mirror to selectively align one of the facets of the faceted mirror with the one of the optical paths with which the faceted mirror is associated. The facets of each of the faceted mirrors corresponding to one of the sets of optical paths, i.e., the set of input optical paths or the set of output optical paths, are preferably angled to reflect light towards a different one of the faceted mirrors corresponding to the other of the sets of optical paths, i.e., the set of output optical paths or the set of input optical paths, respectively.

Abstract: A polarization device comprising: a light path; a micro lens array disposed in the light path for separating light into a plurality of individual beams of light; a polarization filter disposed in the light path to receive a plurality of the beams of light and to transmit the received light of a desired polarization state and reflect the received light of a perpendicular polarization state that is perpendicular to the desired polarization state; and a reflecting polarization converter disposed to receive and reflect the reflected light of the perpendicular polarization state and to convert the perpendicular polarization state to the desired polarization state.

Abstract: The network comprises topographic network devices and communication links interconnecting the topographic network devices. The topographic network devices each have a physical location represented by a topographic coordinate set, and a network address that includes the topographic coordinate set. A message configured for transmission through the network includes a destination coordinate set, which is the topographic coordinate set of a destination network device that is one of the topographic network devices. A topographic network device comprises channels, a coordinate store and a topographic processor. The channels are each configured for connection via a communication link to another of the topographic network devices. The channels include a first channel via which the message is received. The coordinate store stores connected device coordinate sets, which are the topographic coordinate sets of the topographic network devices to which the channels are directly connected.

Abstract: A network for communicating a message is established by providing a network that includes topographic network devices and communication links interconnecting the topographic network devices. The topographic network devices each have a physical location represented by a topographic coordinate set. A network address is assigned to each of the topographic network devices. The network address includes the topographic coordinate set of the topographic network device. The topographic coordinate set of the topographic network device is transmitted to those of the topographic network devices directly connected to the topographic network device. The topographic coordinate set of the topographic network device is received and stored at at least one of the topographic network devices directly connected to the topographic network device.

Abstract: The optical fiber-based communication system comprises a distribution optical fiber that extends proximately to a plurality of end users, and tap-off modules coupled to the distribution optical fiber at intervals along its length. Each of the tap-off modules includes a port in optical communication with the distribution optical fiber. The optical fiber-based communication system additionally comprises a branch optical fiber connected to the port of each of at least some of the tap-off modules and that extends to a corresponding one of the end users.

Abstract: An underwater telecommunications system has a first underwater cable for carrying data traffic, one or more underwater repeaters, and an underwater power network for supplying power to the repeaters. By providing a separate cable for some or all of the power supply, the power route may be made shorter, thus more power can be delivered, therefore more repeaters can be used, which enables more fiber pairs to be laid, and thus the capacity to be increased.

Abstract: The tunable optical filter comprises a Fabry-Perot cavity and a controlled-index device. The controlled-index device is located in the Fabry-Perot cavity and has a refractive index responsive to a control signal. The Fabry-Perot cavity has at least one resonant optical frequency that depends on the refractive index of the controlled-index device. The Fabry-Perot cavity has a maximum transmissivity for light having a frequency equal to its resonant optical frequency, and attenuates light whose frequency differs from the resonant optical frequency. Thus, the control signal controls the frequency of the light transmitted by the tunable optical filter.

Abstract: The optical receiver comprises an optical input path, a light detector array, an optical converging element and an information signal generator. The light detector array includes light detectors and a light-sensitive surface. Each light detector generates an electrical signal in response to light. The optical converging element is located to focus an optical input signal received via the optical input path to form a spot on the light-sensitive surface of the light detector array. The spot has an area less than the area of the light-sensitive surface but greater than the area of one of the light detectors. The information signal generator generates an electrical information signal from at least one of the electrical signals. In an embodiment, the information signal generator includes a summer that sums the electrical signals generated by the light detectors to generate the electrical information signal.

Abstract: An underwater data transmission system has a cable for carrying an optical signal to carry data, and a string of repeaters spaced apart along the cable, for transmitting the data along the cable, and is upgradeable in mid life by including an upgradeable repeater. The system may have a switchable loop to enable upgrading by adding an additional repeater to the loop and switching the loop into the data path. This enables the data capacity to be increased without needing to lift all the repeaters to the surface. This can enable the huge deployment costs of underwater systems to support several generations of advances in optical transmission systems. It makes more use of the usual twenty year design life of the physical infrastructure.

Abstract: An underwater telecommunications system has a first underwater cable for carrying data traffic, one or more underwater repeaters, and an underwater power network for supplying power to the repeaters. By providing a separate cable for some or all of the power supply, the power route may be made shorter, thus more power can be delivered, therefore more repeaters can be used, which enables more fiber pairs to be laid, and thus the capacity to be increased.

Abstract: A micro display system is provided that uses ambient light to illuminate the microdisplay. A wave-guide contains an embedded dye which absorbs ambient light through the surface of the wave-guide and re-emits light. Total internal reflection in the wave-guide and reflection from a reflector at one end of the wave-guide direct all the re-emitted light through a light-transmissive end to an illuminator for illuminating the microdisplay with polarized light. The microdisplay has a plurality of pixels which are activated to selectively reflect polarized or rotated polarized light back through the illuminator where the polarized light forms an image for a user.