Abstract: The invention relates to methods of making color selection deflection electrode structures for use in color picture display tubes having a channel plate electron multiplier arranged adjacent a screen, the deflection electrode structure being disposed intermediate the multiplier and screen and consisting of pairs of elongate, rectangular electrodes aligned with rows of output apertures of the multiplier and operable to control the direction of an electron beam emanating from those apertures so as to impinge upon a selected one of a plurality of different color phosphors in repeating pattern comprising the screen. The methods involve the steps of forming slits (1) in a pair of thin metal sheets, e.g.

Abstract: An envelope of a cathode-ray tube comprises a metal rear housing (1) and a glass face-plate (3) which is sealed in a vacuum-tight manner to a flange (2) on the rear housing by means of a seal (4) formed between the face-plate and the flange. To prevent the face-plate from peeling away from the seal and/or the seal from peeling away from the flange of the rear housing when the face-plate deflects inwards during evacuation of the envelope, spring clamps 5 are provided on the edges of the face-plate and flange, each clamp consisting of a spring-steel channel member with wall portions (9a and 9b) which converge towards the mouth of the channel member. The channel member, at parts (10a and 10b) thereof which bound or adjoin the converging wall portions where these portions are nearest one another, engage the front and rear surfaces (6 and 7) of the face-plate and the flange respectively to exert clamping forces on these surfaces in directions substantially perpendicular thereto.

Abstract: A bolometric detector comprising an optical immersion lens and a pyroelectric detector element mounted so as to be spaced from the lens. The detector may be mounted spaced from the lens by an air gap, by a foraminous spacer, or by a cement having a low thermal conductivity.

Abstract: Channel plate image intensifiers, for use as raster intensifiers in cathode ray tubes for example, comprise a stack of alternately arranged perforate laminar dynodes M and perforate laminar separators D aligned to form electron multiplier channels P. Each of the separators comprise a perforate aluminium plate having an anodized layer some 15 microns thick on the plate surface. Such separators can be manufactured to have the desired electrical characteristics and uniform thickness over their entire area so that the dynodes M are parallel to each other and provide a uniform gain over their entire area.The invention also relates to a method of anodizing perforate and imperforate aluminium foils.

Abstract: An electron display tube has its flat glass plate sealed to the flange of its metal cone, or funnel, by the use of a pressure deformable metal strip between the flange and the plate and several U-shaped clamps at the edge of the flange and plate urging the plate and flange towards each other and a metal rimband around the edges of the plate and flange and embracing the clamps so as to maintain them in compression.