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. 30, 1990
Filed:
Aug. 29, 1988
Applicant:
Inventor:
Roy N Peacock, Lafayette, CO (US);
Assignee:
MKS Instruments, Inc., Andover, MA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01L / ; G01L / ;
U.S. Cl.
CPC ...
324460 ; 324464 ; 324459 ;
Abstract
A method and circuit for measuring the pressure of a gas with a cold cathode ionization gauge by measuring the electrical resistance or conductance of the gauge to thus extend the measurement range of the gauge. Current into the gauge may be limited to a substantially constant value at pressures greater than about 10.sup.-6 Torr, for example, so that the gauge voltage varies monotonically with respect to pressure at pressures greater than 10.sup.-6 Torr.