Abstract: A method is proposed for eliminating so-called halo blocked apertures in color picture cathode-ray tubes. The cathode-ray tube comprises an evacuated envelope having therein a luminescent viewing screen, an electron gun for producing at least one electron beam for exciting the screen to luminescence and an apertured mask closely spaced from the screen for selectively intercepting and transmitting portions of the electron beam. A getter is provided for coating an interior surface of the apertured mask with a gas-sorbing, conductive getter material film. The halo blocked apertures are caused by insulative negatively-charged particles attached to the interior surface of the apertured mask. The conventional tube processing includes the steps of getter flashing, cathode discharge ball gap, cathode conversion, hot shot, first low voltage age, implosion proofing, external coating, frit breakdown check, radio frequency spot knock and final low voltage age.

Abstract: Method of testing a completed cathode-ray tube comprises applying a higher-than-operating voltage between the metal structure around the sidewall of the panel of the tube and the internal conductive coating on the funnel of the tube whereby the panel-to-funnel sealing layer is punctured if it does not have sufficient electrical-breakdown strength.

Abstract: In a method of making a virgin CRT (cathode-ray tube), soon after the panel and funnel are sealed together to form a bulb, the inside of the bulb is flushed with wet carbon-dioxide gas and then flushed with dry noncontaminating gas. Subsequently, the mount assembly is sealed into the funnel, and then the bulb is exhausted, sealed and gettered to produce the finished CRT.

Abstract: In a method for sealing a glass stem into the neck of an electron tube, the stem, which is supported on a mount pin, is positioned in the neck, which is longer than desired. The neck is then heat sealed, as by fusion, to the stem, and the excess glass or cullet is cut off, whereby the cullet falls on, around and sticks to the mount pin. The novel method includes releasing the cullet from the mount pin without substantially fracturing the cullet. Then, the released cullet is removed from the vicinity of the mount pin, again without substantially fracturing the cullet.