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AssigneeKoninklijke Philips Electronics N.V.
InventorsGehardus Meintes Oosterhout, Hermanus Nicolaas Tuin
Estimating the term…
A method for producing CRT screens includes the step of reducing the cooling rate of part of a press-formed glass screen during the cooling stage. The outside portion of the screen, i.e., the side normally facing a viewer, normally has a higher cooling rate than the inside portion of the screen, which leads to unwanted stresses in the finished product. The cooling rate of the outside portion of the screen is reduced by reflecting the heat radiating from the outside portion during the cooling process, and/or providing extra heat to the outside portion from a heater. The reduction in the cooling rate is preferably done during the transport of the glass screen from the press to the cooling oven. The method provides for systematic cooling of the inside and outside portions of the glass screen at nearly the same cooling rate.
A method for manufacturing a glass panel having an inner and an outer face portion, said panel comprising a viewing window and peripheral side walls, for a display tube, comprising a first stage of press-forming molten glass put in a mold and a second stage of cooling the formed glass after it has been taken out from the mold, wherein during at least a part of the second stage the heat radiation of the outer face portion of the panel is reduced to reduce a difference in cooling rate between the inner and outer face portion of the panel.
Dependencies are inferred from the claim text.