Patents by Inventor Christopher L. Chua

Christopher L. Chua 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: 10717299
    Abstract: An imaging system includes first and second heaters configured to pre-heat a thermochromic coating. The first heater heats at least one of a substrate and the thermochromic coating disposed on the substrate. The second heater heats an ambient environment surrounding the thermochromic coating. The first and second heaters are configured to pre-heat the thermochromic coating to a temperature below a threshold temperature of the thermochromic coating. The system further includes a patterned heater configured to heat the pre-heated thermochromic coating to one or more temperatures above the threshold temperature according to a predetermined pattern.
    Type: Grant
    Filed: April 12, 2019
    Date of Patent: July 21, 2020
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Ashish Pattekar, Christopher L. Chua
  • Publication number: 20200207015
    Abstract: A method for providing high-speed three dimensional (3D) printing is provided. The method includes producing at least one three dimensional (3D) printed part. Producing the 3D part includes continuously constructing to extend outwardly a diameter of a rotating cylindrical core via continuous deposition of a layer, and defining a first pattern in the continuously deposited layer corresponding to a cross-section of the at least one 3D printed part.
    Type: Application
    Filed: December 31, 2018
    Publication date: July 2, 2020
    Inventors: Ashish V. Pattekar, Warren Jackson, Anne Plochowietz, Jengping Lu, Jamie Kalb, Christopher L. Chua, Carolyn Moorlag, Eugene Beh
  • Publication number: 20200180334
    Abstract: Formation of a multi-colored image in thermochromic material involves controlling operation of first, second, and third heat sources. The first heat source heats pixels of the thermochromic material to activate the pixels. The second and third heat sources are selectively controlled to heat different sets of pixels using neither, one, or both of the second and third heat sources.
    Type: Application
    Filed: December 6, 2018
    Publication date: June 11, 2020
    Inventors: Fatemeh Nazly Pirmoradi, Christopher L. Chua, Kyle Arakaki, Jacob N. Chamoun
  • Patent number: 10649243
    Abstract: An article includes a substrate with at least first and second materials disposed in or over the substrate. The first material is a non-color changeable material of at least one first color and the second material is a thermochromic color changeable material activated to produce at least one second color different from the first color. Additive color mixing of the first and second colors produces at least one third color different from the first and second colors.
    Type: Grant
    Filed: July 30, 2018
    Date of Patent: May 12, 2020
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Warren B. Jackson, Christopher L. Chua, Ashish Pattekar
  • Patent number: 10634760
    Abstract: A computer-implemented system and method for object tracking via identifier-tracker pairings is provided. An identifier with data for a tracker is received. The tracker is paired with the identifier and also associated with an object. The tracker is identified based on the received identifier. A location of the tracker is determined by obtaining readings regarding the tracker on a periodic or continuous basis and calculating the tracker location from the last obtained readings or by requesting readings regarding the tracker upon receipt of the identifier and calculating the tracker location from the requested readings. The location of the tracker is designated as a location of the object associated with the tracker.
    Type: Grant
    Filed: May 1, 2017
    Date of Patent: April 28, 2020
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Christopher L. Chua, Ashish V. Pattekar
  • Patent number: 10583678
    Abstract: An approach for forming a multi-colored image on a substrate that includes a thermochromic material capable of producing at least two different colors is disclosed. Individually selected pixels of the thermochromic material that correspond to the image are heated to predetermined temperatures. Each predetermined temperature corresponds to a predetermined color shift of the thermochromic material. While the individually selected pixels are being heated, an area that includes the individually selected pixels is flooded with an amount of UV radiation sufficient to at least partially polymerize the thermochromic material. A color of each individually selected pixel is determined by a predetermined temperature to which the pixel is heated and the amount of UV radiation to which the pixel is exposed.
    Type: Grant
    Filed: December 6, 2018
    Date of Patent: March 10, 2020
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Fatemeh Nazly Pirmoradi, Christopher L. Chua, Yu Wang
  • Patent number: 10583669
    Abstract: A method of forming a multi-colored image on a substrate that includes a thermochromic material capable of producing at least two different colors is disclosed. The method includes heating individually selected pixels of the thermochromic material that correspond to the image to one or more first temperatures sufficient to activate the selected pixels of the thermochromic material for color shift. The area corresponding to the individually selected pixels is flooded with a first UV radiation dosage sufficient to at least partially polymerize the thermochromic material. The individually selected pixels are heated to one or more second temperatures while the area is flooded with a second UV radiation dosage.
    Type: Grant
    Filed: December 6, 2018
    Date of Patent: March 10, 2020
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Fatemeh Nazly Pirmoradi, Christopher L. Chua, Yu Wang, Alex Hegyi
  • Publication number: 20200033643
    Abstract: An article includes a substrate with at least first and second materials disposed in or over the substrate. The first material is a non-color changeable material of at least one first color and the second material is a thermochromic color changeable material activated to produce at least one second color different from the first color. Additive color mixing of the first and second colors produces at least one third color different from the first and second colors.
    Type: Application
    Filed: July 30, 2018
    Publication date: January 30, 2020
    Inventors: Warren B. Jackson, Christopher L. Chua, Ashish Pattekar
  • Patent number: 10481404
    Abstract: A light beam shaper has a rectangular cavity bounded by wafer sidewalls and top and bottom caps. The top and bottom caps are wafer-bonded onto opposing surfaces of the wafer. A reflective coating covers inner surfaces of the cavity. A geometry of the cavity changes a light beam entering the cavity into a rectangular beam profile with uniform spatial intensity at the output.
    Type: Grant
    Filed: May 14, 2018
    Date of Patent: November 19, 2019
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Christopher L. Chua, Yu Wang, David K. Biegelsen, Patrick Yasuo Maeda
  • Publication number: 20190346683
    Abstract: A light beam shaper has a rectangular cavity bounded by wafer sidewalls and top and bottom caps. The top and bottom caps are wafer-bonded onto opposing surfaces of the wafer. A reflective coating covers inner surfaces of the cavity. A geometry of the cavity changes a light beam entering the cavity into a rectangular beam profile with uniform spatial intensity at the output.
    Type: Application
    Filed: May 14, 2018
    Publication date: November 14, 2019
    Inventors: Christopher L. Chua, Yu Wang, David K. Biegelsen, Patrick Yasuo Maeda
  • Publication number: 20190311872
    Abstract: A transient electronic device includes electronic elements (e.g., an SOI- or chip-based IC) and a trigger mechanism disposed on a frangible glass substrate. The trigger mechanism includes a switch that initiates a large trigger current through a self-limiting resistive element in response to a received trigger signal. The self-limiting resistive element includes a resistor portion that generates heat in response to the trigger current, thereby rapidly increasing the temperature of a localized (small) region of the frangible glass substrate, and a current limiting portion (e.g., a fuse) that self-limits (terminates) the trigger current after a predetermined amount of time, causing the localized region to rapidly cool down.
    Type: Application
    Filed: June 6, 2019
    Publication date: October 10, 2019
    Inventors: Gregory Whiting, Scott J. Limb, Christopher L. Chua, Sean Garner, Sylvia J. Smullin, Qian Wang, Rene A. Lujan
  • Patent number: 10332717
    Abstract: A transient electronic device includes electronic elements (e.g., an SOI- or chip-based IC) and a trigger mechanism disposed on a frangible glass substrate. The trigger mechanism includes a switch that initiates a large trigger current through a self-limiting resistive element in response to a received trigger signal. The self-limiting resistive element includes a resistor portion that generates heat in response to the trigger current, thereby rapidly increasing the temperature of a localized (small) region of the frangible glass substrate, and a current limiting portion (e.g., a fuse) that self-limits (terminates) the trigger current after a predetermined amount of time, causing the localized region to rapidly cool down.
    Type: Grant
    Filed: July 12, 2018
    Date of Patent: June 25, 2019
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Gregory Whiting, Scott J. Limb, Christopher L. Chua, Sean Garner, Sylvia J. Smullin, Qian Wang, Rene A. Lujan
  • Publication number: 20190172800
    Abstract: A self-destructing device includes a stressed substrate with a heater thermally coupled to the stressed substrate. The device includes a power source and trigger circuitry comprising a sensor and a switch. The sensor generates a trigger signal when exposed to a trigger stimulus. The switch couples the power source to the heater in response to the trigger signal When energized by the power source, the heater generates heat sufficient to initiate self-destruction of the stressed substrate.
    Type: Application
    Filed: January 25, 2019
    Publication date: June 6, 2019
    Inventors: Christopher L. Chua, JengPing Lu, Gregory Whiting, Scott J. Limb, Rene A. Lujan, Qian Wang
  • Patent number: 10249793
    Abstract: A light emitting diode includes an active region configured to emit light, a composite electrical contact layer, and a transparent electron blocking hole transport layer (TEBHTL). The composite electrical contact layer includes tow materials. At least one of the two materials is a metal configured to reflect a portion of the emitted light. The TEBHTL is arranged between the composite electrical contact layer and the active region. The TEBHTL has a thickness that extends at least a majority of a distance between the active region and the composite electrical contact layer. The TEBHTL has a band-gap greater than a band-gap of light emitting portions of the active region. The band-gap of the TEBHTL decreases as a function of distance from the active region to the composite electrical contact layer over a majority of the thickness of the TEBHTL.
    Type: Grant
    Filed: January 29, 2018
    Date of Patent: April 2, 2019
    Assignee: Palo Alto Research Center Incorporated
    Inventors: John E. Northrup, Christopher L. Chua
  • Patent number: 10224297
    Abstract: A self-destructing device includes a stressed substrate with a heater thermally coupled to the stressed substrate. The device includes a power source and trigger circuitry comprising a sensor and a switch. The sensor generates a trigger signal when exposed to a trigger stimulus. The switch couples the power source to the heater in response to the trigger signal When energized by the power source, the heater generates heat sufficient to initiate self-destruction of the stressed substrate.
    Type: Grant
    Filed: July 26, 2016
    Date of Patent: March 5, 2019
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Christopher L. Chua, Jeng Ping Lu, Gregory Whiting, Scott J. Limb, Rene A. Lujan, Qian Wang
  • Patent number: 10164146
    Abstract: A light emitting device includes a p-side heterostructure having a short period superlattice (SPSL) formed of alternating layers of AlxhighGa1-xhighN doped with a p-type dopant and AlxlowGa1-xlowN doped with the p-type dopant, where xlow?xhigh?0.9. Each layer of the SPSL has a thickness of less than or equal to about six bi-layers of AlGaN.
    Type: Grant
    Filed: July 13, 2016
    Date of Patent: December 25, 2018
    Assignee: Palo Alto Research Center Incorporated
    Inventors: John E. Northrup, Bowen Cheng, Christopher L. Chua, Thomas Wunderer, Noble M. Johnson, Zhihong Yang
  • Publication number: 20180330907
    Abstract: A transient electronic device includes electronic elements (e.g., an SOI- or chip-based IC) and a trigger mechanism disposed on a frangible glass substrate. The trigger mechanism includes a switch that initiates a large trigger current through a self-limiting resistive element in response to a received trigger signal. The self-limiting resistive element includes a resistor portion that generates heat in response to the trigger current, thereby rapidly increasing the temperature of a localized (small) region of the frangible glass substrate, and a current limiting portion (e.g., a fuse) that self-limits (terminates) the trigger current after a predetermined amount of time, causing the localized region to rapidly cool down.
    Type: Application
    Filed: July 12, 2018
    Publication date: November 15, 2018
    Inventors: Gregory Whiting, Scott J. Limb, Christopher L. Chua, Sean Garner, Sylvia J. Smullin, Qian Wang, Rene A. Lujan
  • Patent number: 10109410
    Abstract: A method for forming an out of plane structure includes depositing a layer of an elastic material on a substrate wherein the elastic material has an intrinsic stress profile. The layer of elastic material is photolithographically patterned into at least two spaced-apart elastic members. An electrically non-conductive tether layer joins the elastic members. A portion of the substrate is etched under the elastic members to release a free end of each elastic member, while leaving an anchor portion of each elastic member fixed to the substrate. The stress profile of the elastic members biases the free ends of the elastic members away from the substrate forming loops. The structure is electroplated by applying a voltage having a first polarity between an anode and the structure while the structure is in an electroplating bath. Subsequent to the electroplating, the polarity of the voltage between the anode and the structure is reversed.
    Type: Grant
    Filed: January 17, 2017
    Date of Patent: October 23, 2018
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Brent S. Krusor, Christopher L. Chua
  • Patent number: 10056477
    Abstract: A nitride heterojunction bipolar transistor with one or more polarization-assisted alloy hole-doped short-period superlattice layers are described herein. The transistor may comprise a substrate, a sub-collector region coupled to the substrate, a collector region coupled to the sub-collector portion, a base portion region to the collector portion, and a short-period superlattice (SPSL) emitter region coupled to the base portion. The SPSL emitter includes a plurality of first emitter layers and a plurality of second emitter layers that are alternating layers that form the SPSL emitter. The first emitter layers have a lower bandgap than the second emitter layers, and the vertical transport through the SPSL emitter region occurs via quantum tunneling. Other embodiments are also described.
    Type: Grant
    Filed: May 24, 2017
    Date of Patent: August 21, 2018
    Assignee: PALO ALTO RESEARCH CENTER INCORPORATED
    Inventors: Suk Choi, Christopher L. Chua, Noble M. Johnson
  • Publication number: 20180204662
    Abstract: A method for forming an out of plane structure includes depositing a layer of an elastic material on a substrate wherein the elastic material has an intrinsic stress profile. The layer of elastic material is photolithographically patterned into at least two spaced-apart elastic members. An electrically non-conductive tether layer joins the elastic members. A portion of the substrate is etched under the elastic members to release a free end of each elastic member, while leaving an anchor portion of each elastic member fixed to the substrate. The stress profile of the elastic members biases the free ends of the elastic members away from the substrate forming loops. The structure is electroplated by applying a voltage having a first polarity between an anode and the structure while the structure is in an electroplating bath. Subsequent to the electroplating, the polarity of the voltage between the anode and the structure is reversed.
    Type: Application
    Filed: January 17, 2017
    Publication date: July 19, 2018
    Inventors: Brent S. Krusor, Christopher L. Chua