Patents by Inventor Andrew S. Dewa

Andrew S. Dewa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7218439
    Abstract: A method for increasing the resonant frequency of a torsional hinged device having a reduced attaching area between the torsional hinges and the supporting anchors. The resonant frequency is increased by adding a material over the reduced area to stiffen the connection between the torsional hinges and the support anchors.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: May 15, 2007
    Assignee: Texas Instruments Incorporated
    Inventor: Andrew S Dewa
  • Patent number: 7149427
    Abstract: A micromirror array assembly (10, 20) for use in optical modules (5, 17) in a wireless network system is disclosed. The micromirror array assembly (10, 20) includes a plurality of mirrors (29) monolithically formed with a frame (43), attached by way of hinges (55) and gimbal portions (45). Permanent magnets (53) are attached to each of the gimbal portions (45) associated with the mirrors (29). The resulting frame (43) is then mounted to a coil driver assembly (50) so that coil drivers (34) can control the rotation of each mirror (29), under separate control from control circuitry (14, 24). The micromirror array assembly (10, 20) is thus able to support higher signal energy at larger spot sizes, and also enables multiplexed transmission and receipt, as well as sampling of the received beam for quality sensing.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: December 12, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Andrew S. Dewa, Robert C. Keller
  • Patent number: 7009748
    Abstract: A system and method for providing a resonant beam sweep about a first axis. A mirror or reflective surface supported by a first pair of torsional hinges is driven into resonant oscillations about the first axis by inertially coupling energy through the first pair of torsional hinges. A light source reflects a beam of light from the mirror such that the oscillating mirror produces a beam sweep across a target area. The resonant beam sweep is moved orthogonally on the target area by a gimbals portion of the mirror pivoting about a second axis according to one embodiment. A second independent mirror provides the orthogonal movement according to a second embodiment.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: March 7, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Arthur Monroe Turner, Andrew S. Dewa, Mark W. Heaton
  • Patent number: 6992422
    Abstract: A position sensor for a pivoting platform which has a first portion that flexes when the platform pivots and a second portion of the platform that is rigid, utilizes a piezoresistive element on the first portion of the platform. A connecting terminal for the piezoresistive element is on the second portion and thus not subject to the flexing stresses. The platform can have two symmetrical arms as the flexing portion, and a pair of piezoresistive elements can be formed on each of the arms in order to double the output voltage changes with changes in these positions of the platform. A temperature compensating piezoresistive element can be formed on the rigid portion of the platform and connected to the piezoresistive element or elements. The piezoresistive elements can be formed directly on the portions of the platform.
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: January 31, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Mark W. Heaton, Arthur M. Turner, Andrew S. Dewa
  • Patent number: 6964196
    Abstract: A system and method for providing resonant movement about a first axis. A functional surface supported by a first pair of torsional hinges is driven into resonant oscillations about the first axis by inertially coupling energy through the first pair of torsional hinges. The resonant movement may be moved orthogonally on the target area by a gimbals portion of the functional surface pivoting about a second axis according to one embodiment. The resonant oscillation of the functional surface is monitored to detect changes in frequency due to mass changes of the functional surface.
    Type: Grant
    Filed: May 19, 2003
    Date of Patent: November 15, 2005
    Assignee: Texas Instruments Incorporated
    Inventors: Arthur Monroe Turner, Andrew S. Dewa, Mark W. Heaton
  • Publication number: 20040251788
    Abstract: A position sensor for a pivoting platform which has a first portion that flexes when the platform pivots and a second portion of the platform that is rigid, utilizes a piezoresistive element on the first portion of the platform. A connecting terminal for the piezoresistive element is on the second portion and thus not subject to the flexing stresses. The platform can have two symmetrical arms as the flexing portion, and a pair of piezoresistive elements can be formed on each of the arms in order to double the output voltage changes with changes in these positions of the platform. A temperature compensating piezoresistive element can be formed on the rigid portion of the platform and connected to the piezoresistive element or elements. The piezoresistive elements can be formed directly on the portions of the platform.
    Type: Application
    Filed: June 11, 2003
    Publication date: December 16, 2004
    Inventors: Mark W. Heaton, Arthur M. Turner, Andrew S. Dewa
  • Publication number: 20040169911
    Abstract: A micromirror (110) includes a frame portion (112), a gimbal portion (114) and a mirror portion (116) formed from a single piece of material. A plurality of truss members (140/142) are disposed beneath the gimbal portion (114) and mirror portion (116), allowing the gimbal and mirror portions (114/116) to be made of a thinner material, reducing the mass and increasing the resonant frequency of the micromirror device (110).
    Type: Application
    Filed: March 6, 2004
    Publication date: September 2, 2004
    Inventor: Andrew S. Dewa
  • Patent number: 6752931
    Abstract: A process for manufacturing a wafer having a multiplicity of MEMS devices such as mirrors with gimbals formed thereon is disclosed. A silicon wafer having a thickness less than about 300 &mgr;m is attached to a carrier or support wafer by a layer of bonding agent such as a layer or coating of photo-resist. The MEMS devices such as a gimbal mirror are formed on the silicon wafer by providing a mask and etching through the wafer with a DRIE process. Undesired lateral etching at the bottom of the wafer caused by the formation of an electrical charge at the bonding layer is eliminated or substantially reduced by patterning the layer of photo-resist used as the bonding agent such that areas of the support wafer not covered by the bonding layer are aligned with selected etch lines which etch completely through the silicon wafer to form devices.
    Type: Grant
    Filed: August 9, 2002
    Date of Patent: June 22, 2004
    Assignee: Texas Instruments Incorporated
    Inventor: Andrew S. Dewa
  • Patent number: 6733683
    Abstract: A method of manufacturing an array of microstructures, such as a micromirror array assembly (10, 20) for use in optical modules (5, 17) in a wireless network system, is disclosed. The micromirror array assembly (10, 20) includes a plurality of mirrors (29) monolithically formed from a silicon wafer (70) with a frame (43), attached by way of hinges (55) and gimbal portions (45). The wafer is temporarily bonded to a support wafer (60) while permanent magnets (53) are attached to each of the gimbal portions (45) associated with the mirrors (29), through holes etched through the mounting wafer (60). The resulting frame (43) is then mounted to a coil driver assembly (50) so that coil drivers (34) can control the rotation of each mirror (29), under separate control from control circuitry (14, 24). The micromirror array assembly (10, 20) is able to support higher signal energy at larger spot sizes, and also enables multiplexed transmission and receipt, as well as sampling of the received beam for quality sensing.
    Type: Grant
    Filed: August 29, 2001
    Date of Patent: May 11, 2004
    Assignee: Texas Instruments Incorporated
    Inventor: Andrew S. Dewa
  • Patent number: 6731420
    Abstract: An optical matrix switch station (1) is shown mounting a plurality of optical switch units (15, 17), each of which includes a mirror (29), moveable in two axes, for purpose of switching optical beams from one optical fiber to another. A mirror assembly (41) includes a single body of silicon comprising a frame portion (43), gimbals (45), mirror portion (47), and related hinges (55). Magnets (53, 54) and air coils (89) are utilized to position the central mirror surface (29) to a selected orientation. The moveable mirror and associated magnets along with control LED's (71) are hermetically packaged in a header (81) and mounted with the air coils on mounting bracket (85) to form a micromirror assembly package (99) mounted in each optical switch unit.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: May 4, 2004
    Assignee: Texas Instruments Incorporated
    Inventors: John W. Orcutt, Andrew S. Dewa, Herzel Laor, David I. Forehand, James A. Sisco
  • Patent number: 6709948
    Abstract: A process for manufacturing a wafer from a layer of material such as silicon and having a multiplicity of MEMS devices such as mirrors with gimbals formed thereon is disclosed. The features of the devices on the wafer as well as the boundaries which separate individual devices are defined by lines having a constant width so as to avoid microloading effects. Waste areas of the layer of material which are greater than the constant line width are removed as breakout pieces during the release process.
    Type: Grant
    Filed: May 15, 2002
    Date of Patent: March 23, 2004
    Assignee: Texas Instruments Incorporated
    Inventors: Andrew S. Dewa, John W. Orcutt, David Ian Forehand
  • Patent number: 6704132
    Abstract: A micromirror (110) includes a frame portion (112), a gimbal portion (114) and a mirror portion (116) formed from a single piece of material. A plurality of truss members (140/142) are disposed beneath the gimbal portion (114) and mirror portion (116), allowing the gimbal and mirror portions (114/116) to be made of a thinner material, reducing the mass and increasing the resonant frequency of the micromirror device (110).
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: March 9, 2004
    Assignee: Texas Instruments Incorporated
    Inventor: Andrew S. Dewa
  • Publication number: 20040027449
    Abstract: A laser printer using a single surface resonant mirror for providing a bi-directional beam sweep. According to a first embodiment, a dual axis mirror 40 uses a first pair of torsional hinges 54A and 54B to provide the resonant beam sweep and a second pair 50A and 50B of torsional hinges provides movement orthogonal to the sweep to maintain successive images of the sweep parallel to each other. A second embodiment uses two single axis mirrors 98 and 102. The first single axis mirror 102 provides the resonant beam sweep and the second 98 provides the orthogonal movement 100 to maintain parallel printed lines of image.
    Type: Application
    Filed: March 10, 2003
    Publication date: February 12, 2004
    Inventors: Arthur Monroe Turner, Andrew S. Dewa
  • Patent number: 6687132
    Abstract: The present invention discloses drive apparatus for rotating a mirror used for switching light signals. The drive apparatus has reduced internal wiring and uses a base printed circuit board which is mounted to a support printed circuit board by sandwiching conductive ball connections between matching traces or pads on the two printed circuit boards. A drive module is also included between the two printed circuit boards which can be either a drive coil or an electrostatic plate and is used to rotate the mirrors. The use of the bump grid array or conductive ball connections significantly reduces the amount of internal wiring required.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: February 3, 2004
    Assignee: Texas Instruments Incorporated
    Inventors: John W. Orcutt, Arthur Monroe Turner, Andrew S. Dewa, Terence J. Murphy, Kim D. Hyland
  • Publication number: 20040011761
    Abstract: A process for manufacturing a wafer having a multiplicity of MEMS devices such as mirrors with gimbals formed thereon is disclosed. A silicon wafer having a thickness less than about 300 &mgr;m is attached to a carrier or support wafer by a layer of bonding agent such as a layer or coating of photo-resist. The MEMS devices such as a gimbal mirror are formed on the silicon wafer by providing a mask and etching through the wafer with a DRIE process. Undesired lateral etching at the bottom of the wafer caused by the formation of an electrical charge at the bonding layer is eliminated or substantially reduced by patterning the layer of photo-resist used as the bonding agent such that areas of the support wafer not covered by the bonding layer are aligned with selected etch lines which etch completely through the silicon wafer to form devices.
    Type: Application
    Filed: August 9, 2002
    Publication date: January 22, 2004
    Inventor: Andrew S. Dewa
  • Publication number: 20040007069
    Abstract: A system and method for providing resonant movement about a first axis. A functional surface supported by a first pair of torsional hinges is driven into resonant oscillations about the first axis by inertially coupling energy through the first pair of torsional hinges. The resonant movement may be moved orthogonally on the target area by a gimbals portion of the functional surface pivoting about a second axis according to one embodiment. The resonant oscillation of the functional surface is monitored to detect changes in frequency due to mass changes of the functional surface.
    Type: Application
    Filed: May 19, 2003
    Publication date: January 15, 2004
    Inventors: Arthur Monroe Turner, Andrew S. Dewa, Mark W. Heaton
  • Publication number: 20040004775
    Abstract: A system and method for providing a resonant beam sweep about a first axis. A mirror or reflective surface supported by a first pair of torsional hinges is driven into resonant oscillations about the first axis by inertially coupling energy through the first pair of torsional hinges. A light source reflects a beam of light from the mirror such that the oscillating mirror produces a beam sweep across a target area. The resonant beam sweep is moved orthogonally on the target area by a gimbals portion of the mirror pivoting about a second axis according to one embodiment. A second independent mirror provides the orthogonal movement according to a second embodiment.
    Type: Application
    Filed: January 2, 2003
    Publication date: January 8, 2004
    Inventors: Arthur Monroe Turner, Andrew S. Dewa, Mark W. Heaton
  • Publication number: 20040002215
    Abstract: A process for manufacturing a wafer having a multiplicity of MEMS devices such as mirrors with gimbals formed thereon is disclosed. The devices on the wafer include features defined by a wide line between features which extend completely through the wafer, and have a ratio of greater than about 4:1 with respect to the narrow lines which separate individual devices. Each individual device is separated by narrow gaps or line widths which are, for example, about 10 &mgr;m. Thus, the etching process is controlled such that the features defined by the wide lines are etched completely through, whereas the individual devices are separated by narrow lines which are not etched completely through the wafer. Therefore, the multiplicity of devices remain attached together even after the wafer is released from a backing wafer. Thus, the wafer with the many devices still attached together allows further processing such as packaging, testing, transport, etc. without the required handling of individual devices.
    Type: Application
    Filed: June 27, 2003
    Publication date: January 1, 2004
    Inventor: Andrew S. Dewa
  • Publication number: 20030164997
    Abstract: An optical matrix switch station (1) is shown mounting a plurality of optical switch units (15, 17), each of which includes a mirror (29), moveable in two axes, for purpose of switching optical beams from one optical fiber to another. A mirror assembly (41) includes a single body of silicon comprising a frame portion (43), gimbals (45), mirror portion (47), and related hinges (55). Magnets (53, 54) and air coils (89) are utilized to position the central mirror surface (29) to a selected orientation. The moveable mirror and associated magnets along with control LED's (71) are hermetically packaged in a header (81) and mounted with the air coils on mounting bracket (85) to form a micromirror assembly package (99) mounted in each optical switch unit.
    Type: Application
    Filed: November 8, 2002
    Publication date: September 4, 2003
    Inventors: John W. Orcutt, Andrew S. Dewa, Herzel Laor, David I. Forehand, James A. Sisco
  • Patent number: 6586315
    Abstract: A process for manufacturing a wafer having a multiplicity of MEMS devices such as mirrors with gimbals formed thereon is disclosed. The devices on the wafer include features defined by a wide line between features which extend completely through the wafer, and have a ratio of greater than about 4:1 with respect to the narrow lines which separate individual devices. Each individual device is separated by narrow gaps or line widths which are, for example, about 10 &mgr;m. Thus, the etching process is controlled such that the features defined by the wide lines are etched completely through, whereas the individual devices are separated by narrow lines which are not etched completely through the wafer. Therefore, the multiplicity of devices remain attached together even after the wafer is released from a backing wafer. Thus, the wafer with the many devices still attached together allows further processing such as packaging, testing, transport, etc. without the required handling of individual devices.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: July 1, 2003
    Assignee: Texas Instruments Incorporated
    Inventor: Andrew S. Dewa