Patents by Inventor David P. Baxter

David P. Baxter 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).

  • Optical sensor and sensing method with stray illumination compensation
    Patent number: 8283620
    Abstract: An optical sensor includes an infra red LED, a photodetector and a lock in charge amplifier. The photodetector passes charge to a feedback capacitor of the charge amplifier following an illumination cycle during which the LED is emitting and also following an illumination cycle during which the LED does not emit. An amplifier presents an output indicative of the difference between the charge generated at the photodetector during the illuminated and non-illuminated cycles.
    Type: Grant
    Filed: September 8, 2009
    Date of Patent: October 9, 2012
    Assignee: STMicroelectronics (Research & Development) Ltd
    Inventors: Jeffrey M. Raynor, David P. Baxter
  • OPTICAL SENSOR AND SENSING METHOD
    Publication number: 20100065720
    Abstract: An optical sensor includes an infra red LED, a photodectector and a lock in charge amplifier. The photodetector passes charge to a feedback capacitor of the charge amplifier following an illumination cycle during which the LED is emitting and also following an illumination cycle during which the LED does not emit. An amplifier presents an output indicative of the difference between the charge generated at the photodectector during the illuminated and non-illuminated cycles.
    Type: Application
    Filed: September 8, 2009
    Publication date: March 18, 2010
    Applicant: STMicroelectroncis (Research & Development) Limited
    Inventors: Jeffrey M. Raynor, David P. Baxter