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:
Jun. 30, 1992
Filed:
Dec. 12, 1990
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A color cathode ray tube includes an envelope having, a faceplate, light filtering device provided on an outer surface of the faceplate, and a phosphor screen formed on an inner surface of the faceplate. The phosphor screen is composed of red, blue, and green emitting phosphors. The red emitting phosphor is primarily a Y.sub.2 O.sub.3 :Eu phosphor with an Eu activation amount between 3.0 mol % and 9.0 mol % inclusive with respect to a Y.sub.2 O.sub.3 amount as a base material. The light filtering device is provided in front of the faceplate for selectively transmitting light having a maximum absorption wavelength of 575.+-.20 nm in a wavelength range from 400 nm to 650 nm, and satisfies the following relationship: T.sub.min .ltoreq.T.sub.550 .ltoreq.T.sub.530, 1.ltoreq.T.sub.450 /T.sub.530 .ltoreq.2, 1.ltoreq.T.sub.615 /T.sub.530 .ltoreq.2, 0.7.ltoreq.T.sub.450 /T.sub.615 .ltoreq.1.43, T.sub.615 /T.sub.580-600 .gtoreq.1.1, wherein T.sub.450, T.sub.530, T.sub.505, T.sub.615, T.sub.min and T.sub.580-600 represent the transmissivities for lights of wavelength of 450 nm, 530 nm, 550 nm, 615 nm, the maximum absorption wavelength of 575.+-.20 nm and a maximum absorption wavelength in a wavelength range of 580 nm to 600 nm, respectively.