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:
Nov. 28, 2006
Filed:
Mar. 29, 2005
Peng Liu, Beijing, CN;
Lei-mei Sheng, Beijing, CN;
Yang Wei, Beijing, CN;
Liang Liu, Beijing, CN;
Jing Qi, Beijing, CN;
Shou-shan Fan, Beijing, CN;
Peng Liu, Beijing, CN;
Lei-Mei Sheng, Beijing, CN;
Yang Wei, Beijing, CN;
Liang Liu, Beijing, CN;
Jing Qi, Beijing, CN;
Shou-Shan Fan, Beijing, CN;
Hon Hai Precision Industry Co., Ltd., , TW;
Tsinghua University, Beijing, CN;
Abstract
A cold cathode device () includes a grid (), a cold cathode () positioned under the grid, and a shield electrode () positioned above and parallel to the grid. A vacuum gauge includes a shell (), a collector (), an anode (), and the cold cathode device of the present invention. The cold cathode device and the collector are positioned symmetrically relative to the anode. The collector, the grid and the cold cathode device are received in the shell. The shield electrode can shield an electric field of the grid for preventing from disturbing a symmetrical saddle field in the vacuum gauge. Electrons produced by the cold cathode device can obtain a long electron track because the electron vibration in the saddle field is symmetrical. Thus, the vacuum gauge has an improved sensitivity, and can be widely used to measure pressure in ultra-high and extremely high vacuum conditions.