Abstract: A method of manufacturing a display device having an air-tight envelope, in which a glass face plate and at least one further glass part are joined to form the air-tight envelope that is to be heated and/or evacuated at a later stage of the method of manufacture, comprises inducing a thermoshock in the face plate and/or the at least one further glass part prior to joining the glass face plate and the at least one further glass part to form the air-tight envelope; examining the face plate and/or the at least one further glass part for growth of cracks indicative of defects which could render the air-tight envelope liable to implosion during heating and/or evacuation; choosing between selecting and non-selecting the face plate and/or the at least one further glass part for use as part of the air-tight envelope depending on whether the growth of cracks has been found; using the face plate and the at least one further glass part as part of the air-tight envelope if the growth of cracks was not found; and performi

Abstract: A method of manufacturing a display device comprising an air-tight envelope and at least a glass part (3) which forms part of said air-tight envelope, is characterized in that the glass part (3) is warmed up, during a first time period, at a first temperature (T1), whereafter the glass part is immersed, during a second time period, in a fluid (32) at a second temperature (T2), said second temperature being lower than the first temperature (T2<T1). Preferably, 25°≦T1−T2≦85°, and, in particular, T1−T2≈50°. Preferably, 50° C.≦T1≦100° C., and, in particular, T1≈65° C. Preferably, the glass part is a display window (3) or a cone portion of a display window, and the fluid is water (32).

Abstract: A method in which a (display) device having a part (41) comprising a first wall (43) and a second wall (44) is manufactured, which part (41) is warmed up during the temperature treatment by unilateral irradiation with heat by means of heat radiators (35). The method is characterized in that the temperature treatment further comprises measures which cause a fluid (53) to be fed past the outer surface of the first wall (43) to remove heat from said outer surface and/or measures which cause a fluid to be fed past the inner surface of the second wall (44) to supply heat to said second surface. In an embodiment, the inner surface of the second wall (44) is provided with a heat-absorbing coating (48). Preferably, the heat radiators (35) emit electromagnetic radiation having a wavelength below 3 .mu.m.

Abstract: The invention relates to a method of asymmetrically cleaving a plate (1) of brittle material, in which a thermal load and a mechanical load are provided on the plate (1) and the plate (1) is cleft along a desired cutting line (7).