Abstract:
Prior to assembly of the envelope of a focus grill tube, the cup-shaped panel portion of the envelope is wound with a wire helix which is disposed around and along the panel, each turn of the helix extending across the open side of the panel in predisposed relation with a pattern of phosphor strips on the bottom wall of the panel. Preferably, the helix turns are disposed in grooves in the end surface of the side wall of the panel, and portions of each helix turn are disposed about a member having a thermal expansion greater than that of the helix wire.
Abstract:
Each of the final-sized apertures of an apertured-mask for a cathode-ray tube is closed with a film of an organic material. The central portion of the film closing each final-sized aperture is then opened so as to provide a temporary aperture smaller than the final-sized aperture. An image-screen structure is then photodeposited using the mask with the smaller temporary apertures as a photographic master. After the screen structure is deposited, the organic material is removed to restore the permanent mask with the larger final-sized apertures therein for use in the cathode-ray tube.
Abstract:
The method comprises depositing a thin layer of a first metal having a relatively high degree of solubility in a particular etchant over both plated areas (if a previously deposited pattern is being repaired) and unplated areas on a substrate, this first metal being catalytic to electroless deposition of a second metal to be subsequently deposited, electrolessly depositing on the first metal either an overall pattern of areas of a second metal which has a relatively low degree of solubility in the etchant or a pattern limited to parts of a previously deposited pattern that were missing or incompletely formed, and then treating the plated areas with the etchant, where desired, so that the first metal is removed where it is not covered by the second metal but the second metal is substantially unaffected.