Abstract: According to one embodiment of the invention, the optical security system consists of a first laser beam generation and feedback signal receiving station on one end of the security zone and a second laser beam receiving and feedback signal transmitting station on the other end of the security zone. The first station consists of a laser source that generates a modulated low-divergence laser beam and a first optical signal receiver. The second station consists of a second optical signal receiver that receives the aforementioned modulated low-divergence laser beam emitted from the laser source and a feedback optical signal transmitter which is connected to the aforementioned second optical signal receiver via a signal processing unit which codes the received signal and forms it into a feedback signal to be sent to the first optical signal receiver of the first station from the transmitter of the second station. In the system of the second embodiment the feedback signals are in the form of IR, MW, or RF signals.

Abstract: A method of detecting a signaling congestion situation in a transmitter within a communications switch and for handling and recovering from the congestion. The method functions to (1) monitor the level of the transmit queue for each output port and (2) to monitor the level of the signaling message buffer memory pool for all ports. When the levels of either pass predetermined thresholds, the signaling congestion state is declared. Once the signaling congestion state is declared, the call control or equivalent entity in the communications device stops routing new calls from/towards all ports that are in the signaling congestion state. The call control continues to handle existing calls from/towards ports that are in the signaling congestion state.

Abstract: The invention relates to an apparatus for measuring thickness and deviations from the thickness of thin conductive coatings on various substrates, e.g., metal coating films in semiconductor wafer or hard drive disks. The thickness films may be as small as fractions of microns. The apparatus consists of an inductive sensor and a proximity sensor, which are rigidly interconnected though a piezo-actuator used for displacements of the inductive sensor with respect to the surface of the object being measured. Based on the results of the operation of the proximity sensor, the inductive sensor is maintained at a constant distance from the controlled surface. Variations in the thickness of the coating film and in the distance between the inductive sensor and the coating film change the current in the inductive coil of the sensor.

Abstract: A precision soft-touch gripping mechanism has a mounting plate attached to a robot arm. The plate supports a stepper motor. The output shaft of the stepper motor is connected through a spring to an elongated finger that slides in a central longitudinal slot of the plate and supports a first wafer gripping post, while on the end opposite to the first wafer gripping post the mounting plate pivotally supports two L-shaped fingers with a second and third wafer gripping posts on their respective ends. The mounting plate in combination with the first sliding finger and two pivotal fingers forms the end effector of the robot arm which is thin enough for insertion into a wafer-holding slot of a wafer cassette. The end effector is equipped with a mapping sensor for detecting the presence or absence of the preceding wafer, wafer position sensors for determining positions of the wafer with respect to the end effector, and force sensors for controlling the wafer gripping force.

Abstract: VC multicast implementation scheme utilizing VP tunneling over public ATM VP switched networks utilizing P2P and P2M connections to provide VC multicast capability to the attached private ATM networks. The border ATM VC switch in each private ATM network is connected to the ATM VP switch in the public ATM network via a physical interface adapted to carry one or more P2P VP tunnels. A P2P VP tunnel is established from each VC switch to all other VC switches connected to the public ATM network. A dedicated P2M VP tunnel is established between the source VC switch to each of the destination VC switches connected to the public ATM network. For each multicast connection to be established, a VPI/VCI value pair is allocated over the dedicated P2M VP tunnel used to transmit data associated with all P2M calls for all the P2P VP tunnels carried by the physical interface.

Abstract: The invention relates to an apparatus for measuring thickness and deviations from the thickness of thin conductive coatings on various substrates, e.g., metal coating films in semiconductor wafer or hard drive disks. The thickness films may be as small as fractions of microns. The apparatus consists of an inductive sensor and a proximity sensor, which are rigidly interconnected though a piezo-actuator used for displacements of the inductive sensor with respect to the surface of the object being measured. Based on the results of the operation of the proximity sensor, the inductive sensor is maintained at a constant distance from the controlled surface. Variations in the thickness of the coating film and in the distance between the inductive sensor and the coating film change the current in the inductive coil of the sensor.

Abstract: The mapping sensor system of the invention is intended for use with a mechanical arm of an industrial robot which loads and unloads flat circular objects, such as semiconductor wafers, into and from wafer cassettes on operations of processing the semiconductor wafers in stand-alone or cluster machines used in semiconductor production. The mapping system consists of a light source, a light-receiving element, and a light beam shaper. The light source is installed on the front end of the robot arm and directs the light via the beam shaper to the leading edge of the semiconductor wafer. The beam reflected from the wafer edge is sensed by a light-receiving element, such as a photodiode. The shaper modifies the shape and the cross-section of the beam directed towards the wafer so as to provide reflection from the curvilinear surface of the edge, irrespective of the existence of the notch, most optimum for detection by the photodiodes and without generation of false signals.

Abstract: The invention describes an apparatus for preventing gripping of objects having wrong dimensions or orientation. The apparatus comprises a part handler, e.g., a holder for parts to be treated in a chemical reactor, where the parts has to be transferred from a working position to a temporary storage. The holder may have different shapes, e.g., rectangular, elliptical, or circular, and is provided with positioning openings or recesses for engagement with pins or semispherical elements on the engaging surface of the part handler. The apparatus is provided with at least two through beam optical sensor units with adjustable divergence of the light beams emitted from the light emitting to the light-receiving element. The sensor units are located near the edge area of the holder.

Abstract: A system comprising a single sender SMS for forwarding multicast traffic is collocated in the same device as the LEC thus creating an optimal distribution path for multicast traffic. This reduces the latency of transmission of multicast traffic from sender to receivers by eliminating the need to transmit cells from the LEC to the SMS via the network and reassemble cells into frames and segment frames into cells. The SMS functions as a private SMS for exclusive use by the LEC alone. The SMS of the present invention enables a LEC to distribute multicast traffic in a very efficient manner. The LEC communicates with the SMS directly via the operating system internal messaging subsystem or equivalent. The multicast traffic is sent on a P2M connection from the sending LEC via the SMS to all the receiving LECs interested in listening to a given MMAC. In a first embodiment, the LEC internally has knowledge of the existence of the private SMS and is inhibited from issuing a LE_ARP_REQ to find the SMS.

Abstract: A method of providing redundancy in a LAN Emulation network in the event an LES fails. The method is light in that it does not require complicated database synchronizations between LECSs and their associated complex message protocol exchanges. The method comprises defining a plurality of LESs per ELAN, but permitting only one of the LESs to be active at any one moment in time. All the LECSs are configured with the same Topology Database which include the all the potential LESs for each ELAN. The LECSs try to connect to each LES and the results are logged. The operative LESs having the highest priority is chosen as the active LES whereby all LECs get assigned to the active LES. When the active LES fails the LECs attempt a new connection to LECs. The LECs assigns the LECs to another operative LES in the database list. All the LECs previously connected to the failed LES, are attached to the new LES assigned by the LECs and communications are reestablished with the new LES.

Abstract: A method of determining an efficient route to a well known address that is particularly applicable to networks that do not have the capability of source routing for calculating routes to specific addresses such as ATM networks based on the IISP protocol. The well known address may represent any entity in the network that provides distributed services (e.g., network server applications) that are to be shared among many nodes and applications on the network, such as LECSs. The method of functions to automatically and dynamically register ‘well known’ addresses on the ports of each node that implements the invention. This permits applications on the network to route to the destination in the shortest possible path thus utilizing network resources in an efficient manner. If there is more than one location with the well known address, e.g., a redundant LECSs in the network, or more than one route to the location then the optimum location will be the one routed to.