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:
Aug. 07, 1990
Filed:
Feb. 28, 1989
Giovanni Busca, Bevaix, CH;
Leland Johnson, La Chaux-de-Fonds, CH;
Oscilloquartz S.A., Neuchatel, CH;
Abstract
The passive frequency standard of this invention comprises a cell (42) containing Rb87 and a source of predetermined spectral component which, by optical pumping, empties the level F=1, m.sub.F =0 and populates the level F=2, m.sub.F =0. This source comprises a lamp (40) and an isotopic filter constituted by Rb 85 contained in the cell (42). A helicoidal resonator (44) is tuned to the transition frequency between level F=2, m.sub.F =0 and level F=1, m.sub.F =0. It receives an excitation signal for stimulating such transition from an oscillator via a connector (64). The frequency of the oscillator is slaved to the transition frequency by slave means comprising a photoelectric cell (46) which receives the light from the lamp (40) through the cell (42).