1971 results about "All optical" patented technology

Disclosed is an all-optical frequency upconverter in a radio-over-fiber system that outputs upconverted optical radio frequency (RF) signals using an optical intermediate frequency signal and an optical local oscillation signal. The all-optical frequency upconverter includes a semiconductor optical amplifier that mixes the optical intermediate frequency signal with the optical local oscillation signal through four wave mixing, and an optical filter that filters a plurality of frequency component signals, which are generated through the four wave mixing, to extract optical RF signals. According to the invention the system configuration can be made simple, and wide LO and IF frequency bandwidths can be provided.

An imaging system and method are presented. The system comprises an imaging lens unit, an imaging detector, and a birefringent element located between the imaging lens unit and the imaging detector. The system is thus configure and operable to provide in-focus imaging of objects located at both near-field and far-field ranges. Also provided is an optical device configured to be mounted on an imaging lens, being one of the following: a lens of an individual's glasses, on a contact lens, and an eye internal lens. The optical device is configured to be located between the imaging lens and the retina and comprises a birefringent element, to thereby provide in-focus imaging onto the retina of the objects located at both near-field and far-field ranges therefrom.

An exit pupil extender with one input optical element and two exit optical elements disposed on different sides of the input optical element. The exit pupil extender also comprises two intermediate optical couplers, each disposed between the input optical element and one exit optical element. The couplers serve as exit pupil extending components. All optical elements and couplers are diffractive optical elements having grating lines. The grating lines of one optical element are substantially parallel to that of other optical elements, but the grating lines of the couplers are at substantially a 60-degree angle from that of the optical elements in order to optimize the exit pupil extending efficiency.

Loss of optical signal is detected in a synchronous communications system by detecting features of a monitor signal occurring at a detection frequency corresponding to the frame rate. Since the frame rate is substantially less than the bit rate, monitoring and detection can be performed at a lower bandwidth than the bit rate. An auto-correlation circuit utilises delays which are an integral multiple of the frame rate and produces a detection value which is compared with a threshold value. Alternatively, detection may be based on a power measurement of a band pass filtered monitor signal by setting the lower bandwidth limit above zero frequency and normalizing the measurement of power relative to an average power measurement. A loss of signal may then be detected by a change in power measurement relative to a threshold and can be used for asynchronous systems as well as synchronous systems. Loss of signal detection may be utilised to control an optical switch to re-route optical signals and generate alarm signals. The use of such detection in all optical networks avoids the requirement for electronic processing at the bit rate as a means of detection of loss of signal.

An all optical network for optical signal traffic has at least a first ring with at least one transmitter and one receiver. The first ring includes a plurality of network nodes. At least a first add / drop broadband coupler is coupled to the first ring. The broadband coupler includes an add port and a drop port to add and drop wavelengths to and or from the first ring, a pass-through direction and an add / drop direction. The first add / drop broadband coupler is configured to minimize a pass-through loss in the first ring and is positioned on the first ring.

According to exemplary embodiments of the present disclosure, it is possible to provide method, system, arrangement, computer-accessible medium and device to stimulate individual neurons in brain slices in any arbitrary spatio-temporal pattern, using two-photon uncaging of photo-sensitive compounds such as MNI-glutamate and / or RuBi-Glutamate with beam multiplexing. Such exemplary method and device can have single-cell and three-dimensional precision. For example, by sequentially stimulating up to a thousand potential presynaptic neurons, it is possible to generate detailed functional maps of inputs to a cell. In addition, it is possible to combine this exemplary approach with two-photon calcium imaging in an all-optical method to image and manipulate circuit activity. Further exemplary embodiments of the present disclosure can include a light-weight, compact portable device providing for uses in a wide variety of applications.

A polarization independent (PI) interferometer design that can be built from standard optical components is described. Based upon a Michelson interferometer, the PI interferometer uses a 50 / 50 splitter and Faraday Rotator Mirrors (FM's). The interferometer achieves good optical characteristics, such as high extinction ratio (ER) and low insertion loss (IL). Lack of polarization sensitivity reduces interferometer construction tolerances and cost, enhances performance and utility, and expands the scope of interferometric based devices. Such characteristics can be used to construct flexible, high performance, polarization insensitive, multi-rate, self-calibrating, optical DPSK receivers, power combiners, optical filters and interleavers, all-optical switches, and cascaded interferometers. Since polarization is not maintained in standard fiber optic networks, a PI-DPSK receiver allows for use of more sensitive DPSK communications over fiber, without need for costly polarization control hardware. Other applications of PI interferometers include optical CDMA, secure communications, optical coherence tomography (OCT), and temporal gratings with ultra-precise timing.

A bistable photonic crystal configuration comprises a waveguide sided coupled to a single-mode cavity. This configuration can generate extremely high contrast between the bistable states in its transmission with low input power. All-optical switching action is also achieved in a nonlinear photonic crystal cross-waveguide geometry, in which the transmission of a signal can be reversibly switched on and off by a control input, or irreversibly switched, depending on the input power level.

An optoelectronic device having a flexible substrate and an optical interconnect (i.e. waveguide) comprising a sol-gel based material formed on the substrate. The sol-gel based waveguide is capable of being integrated into an all-optical system and provides for greater interconnect distance and lower signal loss. Other sol-gel based optical devices, such as filters, optical source, detectors, sensors, switches and the like, will be implemented in conjunction with the sol-gel based waveguides to provide for an integrated optical system. Methods of formulating the sol-gel based material and methods for fabricating the sol-gel based devices are also provided.

A system and method for measuring wind velocities are provided. A laser wind velocimeter with a radiation source includes a fiber laser. All optical signals, transmitted and received, are conveyed by optical fibers. An amplifier amplifies a source laser, which is then transmitted to one or more transceivers. The one or more transceivers, each projecting along a different axis, and each with a single optical fiber input / output interface act as both the transmission device to focus the radiation at a target region, and as the receiving system for collecting reflected radiation. The one or more transceivers transmit radiation to the target region. A portion of the reflected radiation collected by the receiving system is analyzed to determine the Doppler shift, which can me used to measure wind velocity

Electronic components of an optoelectronic sensor for a measuring system are arranged on the side of a semiconductor substrate that is facing away from a scale. The semiconductor substrate between electronic components and the scale is removed at those locations where the components emit or detect an electromagnetic beam. In this way, it is possible to arrange all of the electrical connections of the components and further electronic assemblies of the measuring system on a first side of the semiconductor substrate, and all optical components of the measuring system on a second side of the semiconductor substrate.

The present invention describes nanophotonic materials and devices for both classical and quantum optical signal processing, transmission, amplification, and generation of light, which are based on a set of quantum systems having a discrete energy levels, such as atoms, molecules, or quantum dots, embedded in a frequency bandgap medium, such as artificial photonic crystals (photonic bandgap materials) or natural frequency dispersive media, such as ionic crystals, molecular crystals, or semiconductors, exhibiting a frequency (photonic) bandgap for propagating electromagnetic modes coupled to optical transitions in the quantum systems. If the frequency of one of optical transitions, called the working transition, lies inside the frequency bandgap of the medium, then spontaneous decay of the working transition into propagating photon modes is completely suppressed. Moreover, the excitation of the working transition and a photon form a photon-quantum system bound state lying inside the photonic bandgap of the medium, in which radiation is localized in the vicinity of the quantum system. In a quantum system “wire” or a quantum system “waveguide”, made of spatially disordered quantum systems, or in a chain quantum system waveguide made of a periodically ordered identical quantum systems, wave functions of the photon-quantum system bound states localized on different quantum systems overlap each other and develop a photonic passband lying inside bandgap of the photonic bandgap medium. Photons with frequencies lying inside the photonic passband propagate along the quantum system waveguide. Since the working transition cannot be excited twice, the passband photons interact with each other extremely strongly both in one waveguide and in different waveguides that are located sufficiently close to each other. These unique nonlinear properties of the quantum system waveguides are proposed to use for engineering key nanophotonic devices, such as all-optical and electro-optical switches, modulators, transistors, control-NOT logic gates, nonlinear directional couplers, electro-optical modulators and converters, generators of entangled photon states, passband optical amplifiers and lasers, as well as all-optical integrated circuits for both classical and quantum optical signal processing, including quantum computing.

A coal mine underground safety comprehensive monitoring system based on fiber grating sensors and belongs to a coal mine underground safety monitoring system. The system comprises an aboveground part and an underground part; the aboveground part comprises a static fiber grating demodulator, a computer data processing system, a printer, a server and a client; the underground part comprises an optical switch array, a working face safety monitoring subsystem and a laneway safety monitoring subsystem; each of the two monitoring subsystems at least comprises a monitoring base station; each monitoring base station at least comprises a survey station; each survey station is corresponding to one group of fiber grating sensors; the advantage is that the system adopts multiple survey stations to perform underground multi-parameter monitoring, integrates the fiber grating sensors, adopts all-optical survey and optical fibers for signal transmission, is intrinsically safe, has high anti-electromagnetic interference capability and a good monitoring effect, realizes real-time continuous long-term on-line monitoring and the sharing of data in an entire mining area to better guide the safety production of a coal mine, can effectively reduce safety accidents of the coal mine and realizes safe and efficient production of the coal mine.

A node, a data processing system, and a data processing method are provided. The node includes a control module, adapted to generate synchronization information and Optical Burst (OB) configuration information; at least one synchronization processing module, adapted to perform a synchronization process on OB paths at a plurality of wavelengths according to the synchronization information; and a cross-connection module, adapted to perform, a cross-connection process on the OB paths, on which the synchronization process has been performed. The data processing system includes at least two nodes, where the nodes are connected through OB paths at one or more wavelengths, and the nodes are adapted to transfer service data through the OB paths. The technical solutions can reduce volume, power consumption, and costs of the nodes, and avoid a problem of generation of data conflict on an optical layer due to lack of optical buffers in all optical switching.

Optical networking has become ubiquitous in providing low cost, high speed communications networks supporting our communication needs from FTTH through long haul to undersea. The large number of users and high speeds provided to each user fiber mean that information retrieval and routing functionality within the data centers hosting this information can become the bottleneck both in terms of speed and latency. According to embodiments of the invention the inventors present architectures based upon all-optical passive optical networks that support a distributive approach to latency reduction as well as protocols relating to their deployment. Beneficially, such POCXN concepts exploit optical components already supported by high volume manufacturing techniques as well as CWDM / DWDM techniques for throughput increase.

Optical logic gates are constructed from Mach-Zehnder Interferometer (MZI) optical circuits. A multi-mode interference (MMI) splitter divides a continuous-wave input into two branches of the interferometer. Each branch has a semiconductor optical amplifier (SOA). When a logic input having a logic-high power level is applied to one of the SOA's, cross-phase modulation occurs in the SOA. The phase shift increases through the SOA. The branch coupled to the logic input has a relative phase shift of pi compared with the other branch. When two branches with the pi phase difference are combined, destructive interference occurs, producing a logic low. An MMI combiner or an equivalent phase shifter is used to combine the two branches. The MMI splitter adds a phase shift of pi / 2 to the upper branch but not to the lower branch, while the MMI combiner also adds pi / 2 shifts.

A mask for enhancing the depth of focus of an optical imaging system is designed by optimizing an optical property (transmittance or reflectance) of the mask relative to the intensity distribution in the system's image plane. Preferably, a desired PSF intensity is selected, a desired misfocus parameter range is selected, and the optical property is adjusted to minimize a measure of the departure of the system's PSF intensity, as computed from the mask's optical property, from the desired PSF intensity, over the entire misfocus parameter range. Most preferably, the desired PSF intensity is selected as the inverse Fourier transform of a desired OTF. Preferably, the mask is fabricated as a DOE.

A method and apparatus for all optical orthogonal frequency division multiplexing (OFDM) employing Inverse Fast Fourier Transform / Fast Fourier Transform by integrated coupler interferometrically.

All-optical output precision measuring gauges that sense the displacement of an internal scale grating are disclosed. Each type of gauge includes a compact, miniature, or ultra-miniature optical readhead that includes a light source for transmitting light to the scale grating, and optical-fiber detector channels for receiving light from the scale grating and outputting optical measuring signals from the gauge. In various embodiments, the optical-fiber detector channels have respective phase grating masks for receiving a periodic light pattern that moves in correspondence to the scale grating, and the channels are arranged in balanced pairs. In various embodiments, the optical readhead is an interferometric-type optical readhead that provides a measuring resolution as fine as 10-50 nanometers or less. In various embodiments, the gauge is provided in an unprecedented miniature size. In various embodiments, the gauge is motorized to provide a precision actuator.

The present invention provides an optical networking device for re-amplifying, re-shaping, and re-timing an optical signal, as well as providing distortion compensation and performance monitoring of the optical signal. The optical networking device includes an all-optical regenerator device for one or more of re-amplifying, re-shaping, and re-timing the optical signal; a distortion compensator device for compensating for distortion associated with the optical signal; and a quality-of-signal monitoring device for measuring the quality of the optical signal. Preferably, the all-optical regenerator device, the distortion compensator device, and the quality-of-signal monitoring device are disposed within a single module. The quality-of-signal monitoring device measures the optical signal subsequent to distortion compensation. Alternatively, the quality-of-signal monitoring device measures the optical signal subsequent to distortion compensation and all-optical regeneration. In various embodiments, the quality-of-signal monitoring device provides feedback to the distortion compensator device, a distortion compensator device disposed along a line system, one or more of an optical amplifier and a distortion compensator device disposed along the line system, and a transmitter device disposed along the line system.

A method for wavelength division multiplexing (WDM) fiber delay line (FDL) optical buffer routing and scheduling of conflicted variable length data packets through an optical router. The method includes ordering of each conflicted variable length data packet and selecting each of the data packets in turn for routing based on the ordering sequence selected. The sequentially assigned conflicted data packet is assigned a wavelength in the FDL optical buffer from (n) available wavelengths, wherein (n)=lambda1, lambda1, . . . , lambdan, lambda1, lambda1, . . . , lambdan, . . . . Each data packet is converted to the sequentially assigned wavelength (n) and routed to an optical buffer according to the wavelength assignment. If the wavelength of the FDL optical buffer is fully occupied the data packet is dropped.

This invention relates to the design of a scaleable high performance multiservice network based on programmable transport. A meshed network with dynamically-adjustable link capacities and nodes which provide data packing into "containers" for transport is proposed. A ring-based network, exchanging data containers among its nodes, is the preferred implementation, due to its flexibility, maintainability, and high reliability. With lossless rings, the quality of service is controlled solely by the origin and destination nodes, without any interference from other data streams. Flexible programmable transport greatly improves the performance, simplifies the controls, and facilitates scaleability. The concept is a departure from classical network thinking. By reducing the complexity of the network core, an economical, reliable, and manageable network with feature-rich edge nodes can be realized. An architecture with recursive ring-based structures provides a high degree of flexibility in bandwidth allocation and is compatible with current transport networks and future all-optical networks.

The invention involves an image sensor camera module and a method of fabricating the image sensor camera module. The image sensor camera module uses a single-body type lens holder defined by a hollow cylindrical body having a shoulder protruding radially inwardly from an inner surface thereof. First and second lenses therein are spaced apart by a first spacer and a filter therein is spaced from the second lens by a second spacer. An image sensor is adhered to a lower rim of the body, and the filter is adhered to an upper rim thereof. All optical elements within the lens holder thus are affixed in fixed relative position compatible with a predefined focal length and axis. Moreover, the adhesively sealed interior of the body of the image sensor camera module prevents particulate contamination.

The network operating system includes an embedded platform for controlling operation of an agile optical network at the physical layer level. At the module embedded level, each module (card-pack) is provided with an embedded controller EC that monitors and control operation of the optical modules. At the next level, each shelf is provided with a shelf processor SP that monitors and control operation of the ECs over a backplane network. All optical modules are connected over an optical trace channel to send / receive trace messages that can then be used to determine network connectivity. At the next, link management level, a network services controller NSC controls the SPs in a negotiated span of control, over a link network. The control is address-based; each NSC receives ranges of addresses for the entities in its control, and distributes these addresses to the SPs, which in turn distribute addresses to the ECs in their control. One of the SPs operates as a router on the link network to relay signaling and control to all entities based on their address. Each NSC constructs, from queried information, a network topology fragment for the embedded elements under its control. A distributed topology system (DTS) shares this topology information with neighboring NSC's to build a complete network view, which can be used by all interested network applications.

A wavelength converter incorporating an on-chip integrated laser for use in an optical system. The converter includes a first port for receiving an optical input signal such as a WDM signal and providing it to an interferometer, and an output port for outputting a signal which is a wavelength-converted version of the input signal. An optical source or laser is fabricated on the chip substrate on which the interferometer is formed for providing operating power to the interferometer. Power levels of the input signal are maintained by adjusting an on-chip semiconductor optical amplifier that receives the optical input signal and provides the amplified signal to the interferometer. In an alternative embodiment, the on-chip optical source is replaced by an on-chip pre-amplifier for an external laser source.

In all-optical networks, optical switching and routing become the most important issues for interconnecting the transport network layers. This invention describes a novel tunable optical add / drop filter for the all-optical wavelength-division-multiplexing (WDM) network applications. This filter can add or drop part of the high transmission capacity signals of a WDM link. It can be used to decentralized access point in the access network or as small core network node to realizing branching points in the network topology. It works in both wavelength and space domains. It has the advantages of: 1) High throughput and low voltage operation; 2) Wide tuning range and therefore, high channel capacity; 3) High isolation and high directivity between input and output ports; 4) Compact device packaging is possible as compares to the conventional grating and mechanical switching type of add / drop filter; 5) Multiple ports add / drop tunable filters can be realized with this invention to interconnect multiple WDM networks. This novel add / drop filter can be used in various WDM topologies. It enhances the performance of the conventional tunable filter by re-routing the rejected wavelengths back to network, which not only save the precious optical energy, but also cut down the return loss of the device.

These and other objects of the present invention are achieved in a method of transmitting optical signal traffic. An all optical network is provided with at least two rings that are geographically dispersed. Each ring includes at least one transmitter and at least one receiver. The available wavelengths are separated into distinct ring bands. The optical signal traffic is shared throughout the entire optical network. Each ring is provided with its own distinct ring band of the optical signal traffic. All of the optical signal traffic is transmittable throughout the optical network. Each receiver is configured to receive only wavelengths in a ring band designated for its associated ring.

The invention discloses an all-optical true random number generator, which comprises an all-optical true random number entropy source, wherein the all-optical true random number entropy source injects output light of a continuous laser device I into a two-section semiconductor laser device through a 3dB optical fiber coupler I and a light attenuator, produces a high-speed chaos self-pulse signal and controls the repeated frequency of the chaos self-pulse signal by adjusting the light injection intensity and the frequency detuning amount. Sampling and subsequent processing are not required; the additional problem caused by signal distortion because of sampling in the prior art is solved; the complexity of a system is greatly reduced; a code rate can be tuned in a large range by changing the light injection intensity and the frequency detuning amount; and the code rate is up to Gbps and can be directly compatible with a light network.

There is provided an optical system, including a light-transmitting substrate (20) having at least two major surfaces (26) and edges, all optical prism (54) having at least a first (58), a second (56) and a third (60) surface, for coupling light waves having a given field-of-view into the substrate by total internal reflection, at least one partially reflecting surface located in the substrate, the partially reflecting surface being orientated non-parallelly with respect to the major surfaces of the substrate, for coupling light waves out of the substrate, at least one of the edges (50) of the substrate is slanted at an oblique angle with respect to the major surfaces, the second surface of the prism is located adjacent to the slanted edge of the substrate, and a part of the substrate located next to the slanted edge is substantially transparent, wherein the light waves enter the prism through the first surface of the prism, traverse the prism without any reflection and enter the substrate through the slanted edge.