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:
Feb. 23, 1982
Filed:
Jun. 26, 1980
Russel R Randall, Houston, TX (US);
Dresser Industries, Inc., Dallas, TX (US);
Abstract
A pulsed source of fast neutrons and a radiation detector system are utilized in a well logging instrument, the detector being responsive to the thermal neutron population decay rate. The inverse of the decay rate is proportional to the measured macroscopic neutron absorption cross-section (Sigma). A Sigma is calculated by taking the natural logarithm of the ratio of the detected radiation counts occurring within two measurement intervals of fixed duration and starting at a fixed time after the neutron burst. This Sigma measurement provides a feedback voltage which is used in altering the starting time of a single measurement interval in a subsequent source pulsing cycle to provide a measured Sigma value.