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:
Mar. 21, 1989
Filed:
Apr. 06, 1988
Jun Mochizuki, Yamato, JP;
Toshio Asanoh, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Disclosed are a method of measuring the color purity of a color display having phosphors in the shape of dots and an apparatus therefor which are capable of quantitatively measuring the state of the phosphors being irradiated with electron beams with high accuracy. Magnetic field is applied to the color display tube from the outside so as to forcibly move an electron beam deflectively along a straight line and a photograph of the phosphor in this state is taken so as to obtain the configuration (the center position, and the radius or the diameter) of the phosphor from the image of the phosphor. After the two center positions of the electron beams in the positive and negative directions of the external magnetic field are then obtained, the center position of the electron beam under no excitation is obtained as the interior division point.