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:
Dec. 04, 1979
Filed:
Apr. 24, 1978
William M Stevens, Loveland, OH (US);
Randam Electronics, Inc., Cincinnati, OH (US);
Abstract
A reference cell simulating the light amplitude spectrum of an alpha scintillation cell containing radon.sup.222. The cell includes a gas-tight container having a transparent window. The interior of the container, aside from the window, has a coating of a luminescent material. Inside of the container lies an amount of radium.sup.226. The radium radioactively decays to produce alpha particles and radon.sup.222. The radon.sup.222 and its daughter particles also undergo radioactive decay to produce further alpha particles. The 1620-year half life of the radium.sup.226 assures an adequate supply of the radon.sup.222 for a greater time period than radon's 3.825-day half life. The production rate of the alpha particles within the container increases for a period of approximately 22 years after the cell's construction. Although the radium.sup.226 generally has a nonuniform distribution in the cell, the produced radon assumes a gaseous form and uniformly diffuses throughout the entire cell. The decay products of the radon.sup.222 return to the solid state and deposit uniformly on the cell's walls. The cell may allow the alpha particles from the radium.sup.226 to contact the luminescent material and produce light. Alternately, the cell may prevent the utilization of these alpha particles by interposing a barricade between the radium and the luminescent material. Making the cell involves coating the inside of the container with luminescent material while leaving the window clear. After placing the radium.sup.226 inside, the cell undergoes permanent sealing against the ingress or egress of gaseous components.