Optical: systems and elements – Optical modulator – Light wave temporal modulation
Reexamination Certificate
2002-05-28
2004-06-01
Sugarman, Scott J. (Department: 2873)
Optical: systems and elements
Optical modulator
Light wave temporal modulation
C359S290000
Reexamination Certificate
active
06744550
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to optical networking devices such as cross-connect switches and, more particularly, to cross-connect switches that use micromachined mirror arrays.
The huge bandwidth of optical fibers, in combination with enormous growth of data and voice traffic, has led to a significant amount of recent development activity in the field of optical communications. Advances have occurred in architectures and network components, such as optical switches.
One approach to optical switching involves the use of micro-machined mirror arrays. Prior efforts using this approach, like those of other approaches, tend to have certain shortcomings, such as limited scalability and a relatively low level of integration.
SUMMARY OF THE INVENTION
In an aspect of the invention, a structure includes a reference member having a raised portion thereon, a mirror suspended above the raised portion and driving devices disposed on the raised portion to impart rotational motion to the mirror in two axes of direction.
In another aspect of the invention, a method of fabricating micro-mirror structures in a micro-mirror strip of micro-mirror structures includes forming a pyramidal structure from a substrate material and defining electrodes on the pyramidal structure.
In yet another aspect of the invention, a micro-mirror strip assembly includes a frame, an array of two-dimensional deflecting mirrors mounted in the frame and dams disposed between the mirrors to block viscous interaction between each of the two dimensional deflecting mirrors and adjacent ones of the two-dimensional deflecting mirrors in the array.
In still yet another aspect of the invention, a hinge includes a plurality of parallel hinge sections provided by vertical slots therein, the slots and parallel hinge sections being dimensioned to provide vertical and lateral stiffness to and a minimal torsion spring constant for the hinge.
Among the advantages of the present invention are the following. The placement of the electrodes on raised structures on a substrate provides for increased electrostatic force, as well as enhanced instability, thus lowering the required drive voltage and enhancing the deflection angles of the mirrors. The slotted hinge has high torsional flexibility and high stiffness (both vertically and laterally). The dam feature overcomes the undesirable effects of the interaction of the flow of air from adjacent mirrors in a micro-mirror strip assembly.
Other features and advantages of the invention will be apparent from the following detailed description and from the claims.
REFERENCES:
patent: 5523878 (1996-06-01), Wallace et al.
patent: 5629790 (1997-05-01), Neukermans et al.
patent: 5648618 (1997-07-01), Neukermans et al.
patent: 6000280 (1999-12-01), Miller et al.
patent: 6044705 (2000-04-01), Neukermans et al.
patent: 6124663 (2000-09-01), Haake et al.
patent: 6175443 (2001-01-01), Aksyuk et al.
patent: 6285490 (2001-09-01), Meier et al.
Chan et al., “Effects of capacitors, resistors and residual charge on the static and dynamic performance of electrostatically-actuated devices,” Center for Integrated Systems, Stanford Univ. 120-129 (1999).
Chu et al., “Analysis of Closed-loop Control of Parallel-Plate Electrostatic MicroGrippers,” Univ. of CA 820-825 (1994).
Dotzel et al., “Silicon Mirrors and Micromirror Arrays for Spatial Laser Beam Modulation,” Technical University Chemnitz-Zwickau, Germany 1997.
Henri et al., “Fabrication, Simulation and Experiment of a Rotating Electrostatic Silicon Mirror With Large Angular Deflection,” Laboratoire d'Analyse et d'Architecture des Systemes, CNRS 7, France. Date N/A.
Seeger et al., “Dynamics and Control of Parallel-Plate Actuators Beyond the Electrostatic Instability,” University of CA. Date N/A.
Van Den Boom et al., “Offset Reduction in Hall Plates: Simulations and Experiments,” Electronic Instrumentation Laboratory, (1988).
Wagner et al., “Infrared Micromirror Array with Large Pixel Size and Large Deflection Angle,” Fraunhofer Institute for Silicon Technology (1997).
Ang Jane
Bajikar Sateesh S.
Calmes Sam
Foster Jack D.
Green John
Dinh Jack
Fish & Richardson P.C.
Sugarman Scott J.
Xros, Inc.
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