Abstract: Integrated mechanical angular alignment-enhancement structures for incorporation into free-space micromachined optical switches are capable of achieving better than 0.1° micro-mirror angular precision and repeatability with the optical switches. The structures open the path to high port-count crossconnects with sufficiently low loss for deployment in practical optical-communications networks.

Abstract: The present invention provides a variety of methods and apparatus for monitoring signal quality and switch operation for optical switches in an optical cross connect. The signal quality can be checked by using a beamsplitter to reflect a portion of the light beam carrying the signal onto a photodetector which is connected to a device which can monitor loss of signal, loss of frame, and other transmission characteristics. The position of a switch or waveguide can be monitored by circuits which detect variable levels of resistance and capacitance based on the switch's position or by reflecting probe light beams off the back of the switching mirror. The present invention also provides a method for determining if the signal quality photodetector is functioning correctly.

Abstract: The invention provides methods and systems for micro-machined tunable delay lines. Particularly, the micro-machined tunable delay lines of the present invention utilize adjustable micro-machined micro-mirrors to alter the path length traversed by an optical signal.

Abstract: Methods and systems for controlling the state of polarization of an optical beam using micro-machined devices are provided. By cascading a number of simple polarization state rotators integrated on a number of silicon substrates, the state of polarization of an optical beam can be effectively manipulated to any point on the Poincaré sphere.

Abstract: An optical switch device redirects a beam of light traveling along a first direction to a second direction and includes a base member, a reflective panel and an actuator. The reflective panel is pivotally connected to the base member and moves between a reflective state and a non-reflective state. In the reflective state, the reflective panel is disposed to redirect the beam of light from the first direction to the second direction. In the non-reflective state, the reflective panel is disposed to permit the light beam to travel along the first direction. The actuator is connected to the base member and the reflective panel and is operative to cause the reflective panel to move to and between the reflective state and the non-reflective state. An array of optical switch devices can be arranged to form a free-space optical matrix crossconnect apparatus.

Abstract: A non-blocking crossconnect apparatus includes a primary bi-directional crossconnect device and a plurality of secondary bi-directional crossconnect devices. The primary crossconnect device has a plurality of pairs of bi-directional signal ports. A first one of each of the plurality of pairs of the bi-directional signal ports are arranged in a first set and a corresponding second one of each of the plurality of pairs of the bi-directional signal ports are arranged in a second set. Each secondary crossconnect device is associated with a respective one of the plurality of pairs of bi-directional signal ports and has a pair of secondary bi-directional signal ports and a pair of bi-directional signal leads.

Abstract: Integrated mechanical angular alignment-enhancement structures for incorporation into free-space micromachined optical switches are capable of achieving better than 0.1° micro-mirror angular precision and repeatability with the optical switches. The structures open the path to high port-count crossconnects with sufficiently low loss for deployment in practical optical-communications networks.

Abstract: A method and apparatus for minimizing optical loss associated with light beam divergence in a free-space micro-machined optical switch is presented. The coupling efficiency of a free-space micro-machined optical switch, that is, how efficiently the switch transfers an optical light beam from an emitting optical fiber to a receiving optical fiber, is obtained by calculating the overlap integral of the wave functions of an optical beam taken in a free-space mode at an entry point in the switch and in a fiber mode at a receiving fiber facet of the optical switch. Since the optical light beam diverges as it propagates through the optical switch, and the propagation distance increases with mirror size, that coupling efficiency is limited by the ratio of the optical light beam radius and the mirror radius of the switch.

Abstract: Integrated mechanical angular alignment-enhancement structures for incorporation into free-space micromachined optical switches are capable of achieving better than 0.1° micro-mirror angular precision and repeatability with the optical switches. The structures open the path to high port-count crossconnects with sufficiently low loss for deployment in practical optical-communications networks.

Abstract: A method and apparatus for curvature-resistant micro-mirror structures to reduce light beam coupling loss due to mirror curvature in free-space micro-machined optical switches is presented. As a significant contributor to light beam coupling loss is the curvature of the micro-mirrors in these cross-connect systems, an improved thick mirror slab utilizing a phosopho-silicate glass (PSG) core is constructed. The PSG core is sandwiched between two poly-silicon layers, thus providing an enhanced, bending-resistant structure which protects the PSG core from the release etchant used in surface micro-machining and substantially reduces mirror curvature. The reflective layer is laid down on top of the enhanced, bending-resistant structure.

Abstract: An optical switch device redirects a beam of light traveling along a first direction to a second direction and includes a base member, a reflective panel and an actuator. The reflective panel is pivotally connected to the base member and moves between a reflective state and a non-reflective state. In the reflective state, the reflective panel is disposed to redirect the beam of light from the first direction to the second direction. In the non-reflective state, the reflective panel is disposed to permit the light beam to travel along the first direction. The actuator is connected to the base member and the reflective panel and is operative to cause the reflective panel to move to and between the reflective state and the non-reflective state. An array of optical switch devices can be arranged to form a free-space optical matrix crossconnect apparatus.

Abstract: Integrated connection-verification system for use in a micro-electro-mechanical system (MEMS) crossconnect device. The system uses application of a dithering signal such as a sinusoidal bias to an electrode plate associated with a micro-mirror switching element to dither the micro-mirror. The optical signal from the dithering micro-mirror is fed through a beam splitter, a portion of the optical signal thus being directed to a photodetector. If intensity modulation in the optical signal corresponding to the frequency of the dithering signal is detected by the photodetector associated with the micro-mirror, the connection path between the desired input and output ports is verified.

Abstract: An optical switch device redirects a beam of light traveling along a first direction to a second direction and includes a base member, a reflective panel and an actuator. The reflective panel is pivotally connected to the base member and moves between a reflective state and a non-reflective state. In the reflective state, the reflective panel is disposed to redirect the beam of light from the first direction to the second direction. In the non-reflective state, the reflective panel is disposed to permit the light beam to travel along the first direction. The actuator is connected to the base member and the reflective panel and is operative to cause the reflective panel to move to and between the reflective state and the non-reflective state. An array of optical switch devices can be arranged to form a free-space optical matrix crossconnect apparatus.

Abstract: A symmetrical optical matrix crossconnect apparatus includes a plurality of optical switch devices with each comprising a first pair of fiber optic ports, a second pair of fiber optic ports and a reflective element. The first pair of fiber optic ports are disposed apart from one another and aligned coextensively along a first optical path. One of the first pair of fiber optic ports emits a first light beam that travels along the first optical path in free space while the remaining one of the first pair of fiber optic ports receives the first light beam. The second pair of fiber optic ports are disposed apart from one another and aligned coextensively along a second optical path. A first one of the second pair of fiber optic ports emits a second light beam that travels along the second optical path in free space while a remaining one of the second pair of fiber optic ports receives the second light beam. The first optical path and the second optical path crisscross each other at an intersection.

Abstract: A bridging apparatus is used with an optical matrix crossconnect mechanism that has an array of reflective panels that are disposed in a plurality of columns and rows and are selectively operative between reflective states and non-reflective states. The bridging apparatus includes at least one light beam splitting device that is peripherally disposed in the array of reflective panels adjacent to an entry position of a light beam. The at least one light beam splitting device is operative in a retracted state to permit the light beam to enter into the optical matrix crossconnect mechanism in an undivided manner. The at least one light beam splitting device is operative in a beam splitting state so that the light beam entering into the optical matrix crossconnect mechanism can be divided into a first light beam portion and a second light beam portion which are directed into the optical matrix crossconnect mechanism in different directions.

Abstract: An optical switch device redirects a beam of light traveling along a first direction to a second direction and includes a base member, a reflective panel and an actuator. The reflective panel is pivotally connected to the base member and moves between a reflective state and a non-reflective state. In the reflective state, the reflective panel is disposed to redirect the beam of light from the first direction to the second direction. In the non-reflective state, the reflective panel is disposed to permit the light beam to travel along the first direction. The actuator is connected to the base member and the reflective panel and is operative to cause the reflective panel to move to and between the reflective state and the non-reflective state. An array of optical switch devices can be arranged to form a free-space optical matrix crossconnect apparatus.

Abstract: A layered optical cross-connect switches signals from a first set of optical fibers to a second set of optical fibers. The optical cross-connect comprises at least two switching layers. The input ports and the output ports of each switching layer are fully interconnected. At least one switching layer is configured to switch at least two signals from the same optical fiber from the first set of optical fibers to the second set of optical fibers. For example, in a wavelength-division multiplex (WDM) system, a switching layer can switch signals from different WDM channels having different wavelengths.

Abstract: A monolithically integrated optical disk pickup head is comprised of three-dimensional collimating focusing lenses, a beam splitter and 45-degree reflectors that define an optical axis in free-space using surface micromachining technology to fabricate hinged vertical optical structures.