Abstract: A method and system for re-routing a multicast stream is provided. The method for re-routing a multicast stream includes: providing a prior multicast forwarding path corresponding to a first route; establishing a new multicast forwarding path between a downstream router and a second upstream router corresponding to a second route; re-routing a multicast stream from said prior multicast forwarding path to said new multicast forwarding path, wherein said multicast stream utilizes said prior multicast forwarding path until said new multicast forwarding path is operational; and pruning said prior multicast forwarding path when said new multicast forwarding path is operational. Therefore, the multicast stream transmitting will not be interrupted during the switchover process of the multicast forwarding path caused by that a unicast route to a multicast source or a rendezvous point has changed.

Abstract: A communications addressing system includes first and second communication devices. The first device is capable of at least sending a message using a system specific transmission protocol. The message has a content portion and an addressing portion. The addressing portion includes a unique identifier of an identified receiving entity. An entity identification system provides a least one communication link for a system specific transmission protocol which is derived from the unique identifier of the receiving entity. A security filter screens messages sent to the identified receiving entity. The second communication device is capable of at least receiving a message using at least one system specific transmission protocol. When a sending entity transmits a message using the unique identifier to the entity identification system, it will determine a communication link for at least one system specific transmission protocol for the identified receiving entity and transmit the message through the security filter.

Abstract: A method and communication device for routing unicast and multicast messages. The method for routing a unicast message includes receiving a first control packet including routing parameters from a group header node, updating a routing table based upon the routing parameters, receiving a second control packet including additional routing parameters from a group node, updating the routing table based upon the additional routing parameters and generating a forwarding table from the routing table when both of the updated steps are completed. The unicast message is routed based upon the forwarding table. A method for routing a multicast message comprises receiving the multicast message, determining if a multicast group destination for the multicast message is in a multicast forwarding table (MFT), determining if the multicast message has been previously forwarded and forwarding the multicast message if the message was not previously forwarded and the multicast group destination is in the MFT.

Abstract: A communication apparatus according to the invention can be applied to constitute each of relay nodes provided to constitute a novel communication network which avoids the problem that the traffic of adjunctive information other than the traffic of essential communication information increases undesirably so that communication efficiency in the communication network is lowered. The communication apparatus comprises an interface unit 12 and a core unit 13. Header data contained in framed data based on a communication signal from a signal receiving portion 21 is transmitted from the interface unit 12 to the core unit 13 and, in the core unit 13, a comparison between the header data and history data preserved in a history database are carried out and a flag responding to a result of the comparison is added to the header data, so that the header data having the flag is transmitted to the interface unit 12 from the core unit 13.

Abstract: A system, apparatus and method to provide NET layer parsing and resynchronization in a physically segmented downhole network are described herein.

Abstract: In a sending peer of a data unit transmission protocol, a first record of a data symbol stream (10) is maintained in terms of one or more first sequences of data units of a first format A, and simultaneously a second record of a data symbol stream (10) is maintained in terms of one or more sequences of data units of a second format B, where the first and second record have a common reference point (14) to the data symbol stream (10).

Abstract: A technique is provided for relaying data packets by an intermediate network node (505-520), the data packets being transported via a protocol, such as SCTP, in which an association containing one or more streams transporting sequenced data packets is established between two network components. The technique receives, by a transport layer, packets with individual sequence numbers from a plurality of inbound streams (310). These packets are forwarded by the transport layer to a user layer without sorting (320). Thereafter, the user layer selects an outbound stream for each of the packets (330), and the packets, each of which having a sequence number that preserves the packet order determined by its original sequence number, are sent to the transport layer for transmission via the selected outbound streams.

Abstract: Aspects of a system for optimizing fragment size for aggregation at the physical layer may include one more switch ICs and/or physical (PHY) layer ICs that enable reception of data packets via a medium access control layer protocol entity. Each received data packet may be fragmented into a plurality of fragment payloads, wherein a length of each of the plurality of fragment payloads is selected from a plurality of candidate lengths. Each of the plurality of fragment payloads may be sent via a PHY layer protocol entity instance selected from a plurality of PHY layer protocol entity instances.

Abstract: A method for communicating packets in a network environment is provided that includes receiving a packet at a network element and identifying a sequence number included in the packet that correlates to awareness information associated with one or more adjacent network elements. A table included in the network element may be updated in order to account for the awareness information included within the packet that has not been accounted for by the network element. In cases where the awareness information included in the packet has already been accounted for, the packet may be ignored.

Abstract: Packets or frames of data may be compressed, encrypted/decrypted, filtered, classified, searched or subjected to other deep-packet processing operations before being distributed through the internet. The microprocessor system and method of the present invention provide for the orderly processing of such data packets without disrupting or changing the sequence in which the data is intended to be transmitted to its destination. This is achieved by receiving frames into an input buffer for processing. Associated with this input buffer is a unit for determining the operation to be performed on each frame. An arbitrator assigns each frame to a processing core engine. An output buffer collects the processed frames, and a sequencer forwards the processed frames from the output buffer to their destination in the same order as received by the input/output buffer. Maintaining the sequence of data transmission is particularly useful in voice transmission, such as videos and movies.

Abstract: Provided is a method and system for confirming label switched path (LSP) connection in a global multi-protocol label switching (GMPLS)-based network. The method includes: collecting LSP hierarchy information; selecting one of a plurality of paths between first and second clients according to the LSP hierarchy information; and confirming the connection of the selected path.

Abstract: A system for accessing the network is disclosed. The system includes a network communication device and a network terminal. The network communication device is coupled to the network for communicating with the network. The network communication device has a management module for outputting a network address information of the network communication device in response to a specific request. The network terminal is coupled to the network communication device for issuing the specific request to request the network address information of the network communication device and then utilizing the network address information of the network communication device to communicate with the network communication device for accessing the network.

Abstract: A method of monitoring the connection of a first end-user device to a network includes determining the amount of bandwidth present, tracking the amount of bandwidth in use by different classes of traffic, and tracking performance of the connection to detect when a threshold crossing has been reached. The threshold associated with a decline in quality of a connection between the first end-user device and the network The method further includes generating data in response to the determined reaching of the threshold and communicating the data to a session controller or a second end-user device that is in a communications session with the first end-user device. The method further includes changing the communications session in response to additional data received from the second end-user device.

Abstract: One embodiment relates to a communication system. The communication system includes a central node that is coupled to a communication channel and configured to individually communicate with a number of network nodes over a frequency range. One of the network nodes can identify a common frequency band that is within the frequency range and on which the central node and network nodes can transmit a signal. Other methods and systems are also disclosed.

Abstract: A high speed packet access (HSPA) protocol architecture includes an HSPA NodeB, an HSPA radio network controller (RNC), and a core network. The HSPA NodeB includes a user plane (UP)/control plane (CP) transmit (Tx) lower radio link controller (RLC) functional layer, a UP/CP receive (Rx) lower RLC functional layer, a medium access control (MAC) functional layer, and a physical layer. The HSPA RNC includes a radio resource controller (RRC) functional layer, a packet data convergence protocol (PDCP) functional layer, a UP/CP Tx upper RLC functional layer, a UP/CP Rx upper RLC functional layer, and a physical layer. The HSPA NodeB is in communication with the HSPA RNC and the HSPA RNC is in communication with the core network.

Abstract: The present invention provides systems and methods for abstracting a network topology into virtual links and supporting both generic and instantiated virtualized links for linking a virtualized topology with actual resources within a domain, providing security over network topology information, providing control over the allocation of resources, and reducing the complexity of advertising.

Abstract: The present invention relates to a method and an apparatus for explicit multicast service in Ethernet for executing an explicit multicast service designed for point-to-point link in Ethernet effectively. According to the present invention, there is provided a method and an apparatus for providing explicit multicast service by a router connected to the Ethernet and apparatus thereof. The method and the apparatus perform as follows: receives the explicit multicast data packet to be transmitted to the Ethernet, detects a path of the explicit multicast data packet by use of the explicit multicast data packet, determines a next node on the path of the explicit multicast data packet, sets an Ethernet address of the next node as an Ethernet address of destination of the explicit multicast data packet, and transmits the explicit multicast data packet to the next node.

Abstract: A system and method that allows nodes of a distributed node network to publish messages to other nodes or objects, where the messages may have different protocols. The protocols are pre-established in advance of transmission, so that any given message can be sent as necessary to a subscribing node, where the subscribing node is equipped to receive the message, even though the message may have a particular associated protocol. Prior to passing messages, the nodes swap publishing tables. This allows each node to know in advance what messages can be expected and what protocol a message will have.

Abstract: Disclosed is a system and method for controlling the devices connected to a control gateway. The system includes one or more devices, a control gateway, a server and an open platform. The control gateway is electrically coupled to the devices. The server provides a plurality of control gateway base drivers. The open platform is electrically connected to the control gateway. According to the device's description and type information provided by the control gateway, the system automatically downloads a corresponding control gateway base driver from the server, and converts a first device service type into a second device service type automatically by the control gateway base driver. Thereby, other internal bundles on the open platform or external control devices that with the second device service type can use the devices connected to the control gateway.

Abstract: A method and system for providing distributed network access point installation and management. A network provider installs and/or operates a plurality of access points at locations of a retail entity. Each access point may provide services such as Internet access, and/or content such as audio, video, text, and/or graphics, among other types of services. A carrier, such as a telephone or cable company, may compensate the network service provider for installation and operation of the access points. The carrier may in turn charge its subscribers for network access at the retail entity locations. A plurality of different carriers may provide compensation and allow respective subscriber access. The network access points may be configured to allow each carrier to present a point of presence to its subscribers at the retail entity locations. The installed network may also provide service for retail entity back office functions.

Abstract: A data relay device includes a plurality of transmission ports that constitutes a logical port, and stores therein a MAC learning table and a CoS distribution table. The data relay device reads a MAC address and a CoS value from a frame, and reads a logical-port ID corresponding to the MAC address from the MAC learning table. The data relay device reads a transmission-port ID corresponding to the logical-port ID and the CoS value from the CoS distribution table, and outputs the frame to a transmission port indicated by the transmission-port ID. On the transmission port, the frame is stored in a transmission queue corresponding to the CoS value, and the frame is transmitted at a shaping rate assigned to the transmission queue.

Abstract: A method for providing TCP/IP offload may include receiving control of at least a portion of Transmission Control Protocol (TCP) connection variables by a TCP/IP Offload Engine operatively coupled to a host. The at least a portion of the TCP/IP Offload Engine connection variables may be updated and provided to the host. The TCP/IP Offload Engine may receive control of segment-variant TCP connection variables. The TCP/IP Offload Engine may update the received TCP segment-variant TCP connection variables, and communicate the updated TCP segment-variant TCP connection variables to the host. A system for providing connection offload may include a TCP/IP Offload Engine that receives control of state information for a particular connection offloaded to a network interface card (NIC). Control of the state information for the particular connection may be split between the NIC and a host.

Abstract: The invention includes a method and apparatus for dynamically establishing a multicast group. The method includes receiving, from a first user device, a request to establish a multicast group including a plurality of parameters adapted for establishing the multicast group, obtaining a multicast address for the multicast group, and establishing the multicast group using the assigned multicast address and the parameters. The parameters include at least one multicast group definition parameter and at least one multicast session description parameter. The multicast address and at least a portion of the parameters are adapted for being provided to a second user device to enable the second user device to dynamically join the multicast group.

Abstract: A surplus amount of token calculating unit calculates a surplus amount of token for a station in which a residual amount of output buffer is smaller than a residual amount of token. A necessary amount of token calculating unit calculates a necessary amount of token for a station in which the residual amount of output buffer is larger than the residual amount of token. A token distributing unit distributes a token within a range of the surplus amount of token to a token counter of a station in which the necessary amount of token has been calculated, from a station in which the surplus amount of token has been calculated.

Abstract: A method and apparatus for sending a channel quality indication (CQI) via a shared channel while a wireless transmit/receive unit (WTRU) is in a Cell_FACH state without having a dedicated channel allocated for the WTRU are disclosed. A WTRU performs a measurement of at least one parameter and generates a CQI based on the measurement. The WTRU then transmits the CQI via a random access channel (RACH). The CQI may be transmitted using an RACH preamble. A plurality of signature sequences may be divided into a plurality of groups. The WTRU may select one group based on the CQI and randomly select a signature sequence among signature sequences in the selected group for transmitting the RACH preamble. The CQI may be appended to the RACH preamble. The CQI may be transmitted via a control part or a data part of the RACH message.

Abstract: Embodiments of the invention include an apparatus comprising a mapping device configured to establish mapping information for delivery order attributes corresponding to different transmission protocol types, and a detection device configured to detect a transmission protocol type for the transmission of data packets. The apparatus further includes a decision device configured to decide whether said detected protocol type is a predetermined type, and a setting device configured to set, based on the mapping information and the decision result, a delivery order attribute as a parameter for transmission of data packets in a packet data network if the predetermined protocol type is not present.

Abstract: Disclosed is a method for estimating an available bandwidth of a network link by transmitting small-sized probing packets using a time stamp function of an Internet control message protocol (ICMP) and using time information of the probing packet returned. According to the invention, even when the separate program or function is not activated in the router, it is possible to easily estimate and monitor the available bandwidth of the exterior network link connected to the network being managed. Accordingly, it is possible to operate the network more stably and to detect the abnormal sign of the network at early stage, thereby quickly coping with it. In addition, it is possible to prevent the excessive traffic or load from being caused in the network.

Abstract: Methods and apparatus for maintaining the maximum achievable data rate on a DSL line, up to and including a rate to which a user subscribes is described. Performance monitoring is conducted on the DSL line on an ongoing basis to determine noise margins in each direction. Each noise margin is compared against pre-determined decreasing/increasing thresholds to determine whether the line characteristics dictate a data rate change without loss of synchronization. The invention supports dynamic provisioning changes including application driven service level change requests, e.g., new bandwidth-on demand services. In some embodiments, a combination of existing and new embedded operations channel (EOC) messages are used to implement the modem data rate changes. New EOC messages may be implemented using some of the reserved and/or vendor proprietary Opcodes currently permitted. Modem assigned data rate changes are implemented without a disruption of service, e.g.

Abstract: Aspects of a system for physical layer aggregation may include one or more switch ICs and/or physical (PHY) layer ICs that enable reception of data packets via a medium access control (MAC) layer protocol entity. Each of the received data packets may be fragmented into a plurality of fragment payloads. Each of the plurality of fragment payloads may be sent to a PHY layer protocol entity instance a physical layer protocol entity instance selected from a plurality of physical layer protocol entity instances.

Abstract: A communication system, network interface, and communication port is provided for interconnecting a network of multimedia devices. The multimedia devices can send streaming and/or non-streaming data across the network. The network accommodates all such types of data and assigns data types to time slots or frame segments within each frame to ensure streaming data maintains its temporal relationship at the receiver consistent with the transmitter. A signaling byte is preferably used to keep track of an amount by which isochronous streaming data occupies a frame segment.

Abstract: A communication system, network interface, and communication port is provided for interconnecting a network of multimedia devices. The multimedia devices can send streaming and/or non-streaming data across the network. The network accommodates all such types of data and assigns data types to time slots or frame segments within each frame to ensure streaming data maintains its temporal relationship at the receiver consistent with the transmitter. A signaling byte is preferably used to keep track of an amount by which isochronous streaming data occupies a frame segment.

Abstract: A storage router and related method are presented for combining multiple host frames, such as Fibre Channel frames, together into a single datagram for tunneling transmission over an IP or similar network. The storage router operates by storing incoming host frames in a host frame buffer. When there is sufficient data in the buffer, multiple host frames are batched together, compressed, and converted into an IP datagram. The number of host frames to be batched together can be established through a variety of tests, including total bytes of data, number of frames, or through a time-out mechanism. The network layer then fragments the datagram into data link level frames, such as 1500 byte Ethernet frames. When the datagram arrives at the final destination, the segmented datagram is reconstructed, decompressed, and the multiple host frames are then extracted and passed on to the recipient host frame network.

Abstract: A sending device dynamically adjusts a target number of data packets in a packet train by projecting a train property in advance of timeout, and adjusts the target accordingly. Preferably, the target size of the packet train is adjusted downward by checking the number of accumulated packets in the train at some predetermined time in the timeout interval, and halving the target packet train size if the accumulated packets number less than some intermediate target. This process can be repeated more than once in the same timeout interval. The target size is preferably adjusted upwards more slowly.

Abstract: A system (104) is provided for filling a SONET SPE (204, 300, 500, 600, 700) with bytes of digital information. The system is comprised of data input ports (1-6) configured to receive payload signals comprised of payload information. The system is also comprised of data processing circuits configured to transfer bytes of payload information in sequence from the payload signals. The data processing circuits are also configured to break the payload information into byte segments. The data processing circuits are further configured to map the byte segments to the SONET SPE in a byte by byte manner. The SONET SPE is comprised of cells. The cells are filled from top to bottom in a manner proceeding row by row, from left to right in each row. A method for filling the SONET SPE with bytes of digital information corresponding to payload signals is also provided.

Abstract: A method and system for partitioning frames into sub-frames, where the frames may be defined according to a reference system standard, and transmitting one or more sub-frames during a pre-designated downlink transmission, and transmitting one or more sub-frames during a pre-designated uplink transmission. A method and system for partitioning frames into sub-frames, transmitting one or more sub-frames including a legacy preamble for communicating with a legacy terminal operating according to a reference system standard during a pre-designated legacy transmission period, and transmitting sub-frames including a supplemental preamble for communicating with a non-legacy terminal operating according to the evolved version of the reference system standard during a pre-designated non-legacy transmission period.

Abstract: A system facilitates improved module organization. The system includes a communication component that enables interaction between a primary module and at least one subsequent module. In addition, a synchronization component that coordinates operation of the primary module with at least one subsequent module through utilization of the communication component, where the synchronization component is included upon the primary module.

Abstract: Erroneous data due to faults are prevented from propagating through a distributed network node having diversely routed communications links by using a fault masking technique that eliminates the 60 ms of error propagation time associated with SONET networks. The fault masking technique can also prevent random bit errors from propagating through the distributed network node. A frame alignment technique used in the network node is scalable for very wide words (e.g., 128 bits) for use with high speed optical communications protocols, such as OC-192.

Abstract: A node (22) of a telecommunications network (2) receives, over a transmission chain (24) subject to packet jitter, packets of a connection involving a client device (26). The node (22) comprises a packet buffer (38) configured to store the packets received over the transmission chain prior to transmission of the packets to the client device (26). The node (22) further comprises a client-conscious scheduler (40) which is configured to schedule the transmission of the packets from the packet buffer (38) over a channel (32) to the client device (26) in accordance with a timing consideration of the client device (26). In an example embodiment, the timing consideration of the client device (26) which is taken into account by the scheduler (40) is avoidance of drain of a playout buffer of the client device.

Abstract: Optical apparatus (110, 500, 600, 800, 1000) for providing light having a selected linear polarization having a polarization ratio, the apparatus (110, 500, 600, 800, 1000) comprising a length of optical fiber (120, 504, 604, 804, 1001) comprising a rare earth for providing light having a first wavelength responsive to receiving pump light having a second wavelength that is different than said first wavelength, wherein if the length of optical fiber (120, 504, 604, 804, 1004) were placed in a first position between the length of fiber (120, 504, 604, 804, 1004) is substantially linearly oriented (20) the fiber (120, 504, 604, 804, 1004) could propagate at the first wavelength a fundamental mode and a plurality of higher order modes and the apparatus (110, 500, 600, 800, 1000) could provide light having a first polarization ratio for the selected linear polarization and an M2 parameter, and wherein the length of fiber (120, 504, 604, 804, 1004) is positioned in a second position that increases the bend loss of

Abstract: A device for generating a laser light beam includes a module. The module includes at least one laser light source, and a mechanical, an electrical and/or an optical interface defined towards an outside of the module.

Abstract: The present invention discloses a high power Q-switched, intracavity frequency-doubled laser for laser ablation of soft tissue. Operating a high power Q-switched laser in a frequent on-off mode is highly desirable for laser prostatectomy. Giant first pulse may occur when a Q-switched laser is switched from laser-ready mode to pulse-on mode due to sudden depletion of stored energy in the gain medium. Such a giant first pulse may cause power damage of intracavity optics. Besides, temperature shock induced by sudden onset of a high power pulse train may cause optical damage on surface coating of intracavity optics. The present invention contemplates to suppress these giant first pulses and temperature shocks through pre-lasing and ramping profile of laser parameters. Reliable and frequent on-off operation of a diode-pumped, Q-switched, frequency-doubled Nd:YAG laser is demonstrated for output power up to 100 W.

Abstract: Provided is a device capable of oscillating a plurality of oscillation modes within a laser medium for obtaining a fundamental wave output which is easy in output scaling and high in luminance, thereby enabling a second harmonic conversion which is high in efficiency. The device includes: a laser medium (5) that is planar, has a waveguide structure in a thickness direction of a cross-section that is perpendicular to an optical axis (6), and has a cyclic lens effect in a direction perpendicular to the optical axis (6) and the thickness direction; a clad (4) that is bonded onto one surface of the laser medium (5); and heat sink (3) that is bonded onto one surface side of the laser medium (5) through the clad (4), and in the device, a laser oscillation includes a laser oscillation that oscillates in a waveguide mode of the laser medium (5), and a laser oscillation that oscillates in a plurality of resonator modes that are generated by a cyclic lens effect of the laser medium (5).

Abstract: A technique for reducing speckle in a projected image includes forming an image using a plurality of laser light emitters. An input to the plurality of laser light emitters is non-mechanically perturbed to a degree sufficient to disrupt wavefront uniformity across the array of laser light emitters.

Abstract: A laser apparatus (100) has a semiconductor laser device (12a to 12c), coolant jetting means (24), and a heatsink (18a to 18c). The semiconductor laser device has a light output surface (50) for emitting laser light. The coolant jetting means has a coolant chamber (53) for accommodating a coolant, an inflow port (54) communicating with the coolant chamber, and a jet port (25) opposing the light output surface of the laser device. The heatsink has a laser mount surface (36) for mounting the semiconductor laser device, and a flow path (68a to 68c) where the coolant (56) jetted from the jet port flows in. When the coolant chamber is fed with the coolant, the jet port jets the coolant onto the light output surface of the semiconductor laser device. Since the light output surface is directly cooled by a jet flow of the coolant, cooling efficiency is excellent.

Abstract: In one embodiment of the invention, in a semiconductor laser in which a first conductivity type lower cladding layer, an active layer that includes a quantum well layer, and a second conductivity type upper cladding layer are formed in this order on a semiconductor substrate, a dopant concentration of the lower cladding layer is not more than 4.0×1017/cm3, and a resonator length is not less than 1500 ?m.

Abstract: The present invention provides a structure of a light-emitting device which prevents the inter diffusion of impurities from the high-doped n-type InP substrate to a p-type current blocking layer. The substrate of the invention is highly doped with sulfur (S) to obtain high quality surface whose etch pit density (EPD) is less than 100 cm?2. The device includes such substrate, an optical guiding portion with an active layer, and a current blocking portion provided so as to bury the guiding portion. This current blocking portion includes, from the side of the substrate, a p-type layer, an n-type layer and another p-type layer. The device of the invention provides an n-type layer that is moderately doped with silicon between the n-type substrate and the p-type current blocking layer to prevent the inter diffusion of impurities from the substrate to the p-type layer.

Abstract: The present invention provides a process to form the diffraction grating involved in the DFB-LD precisely, and a DFB-LD device with precisely formed diffraction grating. The DFB-LD of the invention provides a monitoring layer and another semiconductor layer on the monitoring layer as the diffraction grating. The other layer contains elements except for arsenic or has a composition different from that of the monitoring layer. The diffraction grating may be formed by the dry-etching such as the RIE (Reactive Ion Etching) as detecting a luminescence from arsenic. The process may detect the exposure of the monitoring layer and the termination thereof by the luminescence from arsenic.

Abstract: A magnon laser comprising: a magnon gain medium (MGM) that supports generation of nonequilibrium magnons, and a means for generating nonequilibrium magnons in the MGM further comprising a means for pumping nonequilibrium electrons into the MGM. Propagation of nonequilibrium electrons in the MGM causes generation of nonequilibrium magnons. The MGM is selected from the group consisting of: {ferromagnetic semiconductor; ferromagnetic insulator; and ferromagnetic material}. The merging of nonequilibrium magnons causes generation of terahertz waves.

Abstract: A high efficiency injection device 4, which injects oscillation stage laser light into an optical stable resonator of an amplification stage laser 20, is provided. A discharge electrode 1a is disposed in an oscillation stage laser 10, and is connected to a 12 kHz power supply 15 for discharging the discharge electrode 1a, and also a plurality of pairs of discharge electrodes 2a, 2b are disposed within the optical stable resonator of the amplification stage laser 20, and are connected to 6 kHz power supplies 25a, 25b for discharging the respective electrode pairs 2a, 2b. Discharge voltages are applied alternately to the two pairs of electrodes 2a, 2b in synchronization with the injected light to cause discharge.

Abstract: A method for optically pumping a gain-medium with partially polarized or unpolarized pump-light having a wavelength at which that gain-medium has an absorption that is dependent on the polarization plane of the pump-light is disclosed. The pump-light is directed into the gain-medium. The strongest-absorbed polarization component of the pump-light is substantially absorbed and the weakest-absorbed polarization component is partially transmitted by the gain-medium. The polarization plane of the transmitted component is rotated through 90 degrees and the polarization-rotated pump-light is directed back into the gain-medium, wherein it is substantially absorbed.