The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 2006
Filed:
Jun. 03, 2003
Georgios L. Varsamis, Houston, TX (US);
Gary D. Althoff, Houston, TX (US);
Laurence T. Wisniewski, Houston, TX (US);
Denis P. Schmitt, Katy, TX (US);
Abbas Arian, Houston, TX (US);
James H. Dudley, Spring, TX (US);
Georgios L. Varsamis, Houston, TX (US);
Gary D. Althoff, Houston, TX (US);
Laurence T. Wisniewski, Houston, TX (US);
Denis P. Schmitt, Katy, TX (US);
Abbas Arian, Houston, TX (US);
James H. Dudley, Spring, TX (US);
Halliburton Energy Services, Inc., Houston, TX (US);
Abstract
A downhole crystal-based clock that is substantially insensitive to the factors that cause frequency deviation. The clock may be maintained at a predetermined temperature using a temperature sensing device and a heating device, where the predetermined temperature corresponds to the temperature at which the crystal experiences only slight frequency deviation as a function of temperature. A microprocessor may monitor the clock and compensate for long-term aging effects of the crystal according to a predetermined algorithm. The predetermined algorithm may represent long-term aging effects of the crystal which were derived by comparing the crystal clock to a more accurate clock (e.g., an atomic clock) prior to placing the clock downhole. In this manner, the crystal-based clock may be substantially free from the factors that cause frequency, and therefore time variations.