Abstract: Colour cathode ray tube comprising a colour selection mask tensioned in at least one direction within a metal frame, the said frame comprising, on at least two opposite sides of the mask, vibration damping means of the type comprising a cavity enclosing a mass free to move in the said cavity.

Abstract: Color cathode-ray tube comprising a color selection mask (8) placed on a metal frame (19), the said frame comprising, on at least two opposite sides, means of damping vibrations of the mask, of the type comprising two masses (51) connected to the surface of the frame by a connection having a mechanical clearance between the facing surfaces of the mask and of the frame.

Abstract: Colour cathode-ray tube comprising a colour selection mask (8) placed on a metal frame (19), the said frame comprising, on at least two opposite sides, means of damping vibrations of the mask, of the type comprising two masses (51) connected to the surface of the frame by a connection having a mechanical clearance between the facing surfaces of the mask and of the frame.

Abstract: A color cathode ray tube comprises a color selection mask stretched in at least one direction, the mask comprising on its peripheral surface mask vibration damper means in the form of a coupled oscillator of the type comprising a central part attached to the surface of the mask and two wings extending on either side of the central part.

Abstract: A cathode ray tube comprising a color selection mask made from a material in tension and having a relatively low coefficient of thermal expansion, supported by a frame made from a material having a higher coefficient of thermal expansion. Along at least two sides of the frame are disposed two metal inserts made from a material whose coefficient of thermal expansion is similar to that of the mask. The inserts are secured to the opposed sides of the frame at their middle, and the mask is welded to the inserts. The mechanical problems relating to the differences in expansion of the materials making up the mask and the frame, during the high-temperature tube manufacturing steps, are avoided.

Abstract: A cathode ray tube comprising a color selection mask made from a material in tension and having a relatively low coefficient of thermal expansion, supported by a frame made from a material having a higher coefficient of thermal expansion. Along at least two sides of the frame are disposed two metal inserts made from a material whose coefficient of thermal expansion is similar to that of the mask. The inserts are secured to the opposed sides of the frame at their middle, and the mask is welded to the inserts. The mechanical problems relating to the differences in expansion of the materials making up the mask and the frame, during the high-temperature tube manufacturing steps, are avoided.

Abstract: Color television tube provided with a perforated mask and three aligned electron guns, the openings of the mask far from the center of the mask having a major axis inclined with respect to the vertical, the inclination .alpha. increasing with the distance from the center and this inclination being in the direction opposite to that of the image of a non-inclined slot of the mask that would be produced on the screen, by an optical projection system simulating the tube deflector.

Abstract: Device for illuminating photosensitive light hardenable material for the manufacture of a perforated mask type color cathode ray tube, wherein this device comprises a laser, a light modulator and a deflector to deflect the modulated pencil of light, the light modulator and the deflector being controlled by a computer so that the luminous intensity received by each point of the screen is substantially constant.