摘要:
In a color cathode ray tube apparatus, a shadow mask is fixed on a frame with a predetermined tension for cancelling a thermal expansion of the shadow mask during normal operation of the color cathode ray tube apparatus. The mechanical strength of the longer sides on the frame is higher than that of the shorter sides of the frame by fixing reinforcing plates or ribs on the longer sides in order that the tension of the shadow mask not become uneven.
摘要:
A planar member for a shadow mask is provided, which is hard to generate wrinkles in or break when being pulled at four sides to apply a tension to a beam-selecting area with beam-passing apertures. The planar member comprises the beam-selecting area, a first band frame portion surrounding the beam-selecting area, a second band frame portion disposed around and spaced from the first band frame, a plurality of bridge portions bridging the first and second band frame portions at plural points, and a plurality of outer areas with plural apertures, defined by the first and second band frame portions and two bridge portions. The connecting part of the bridge portion with the second band frame portion is reinforced in such a way that the width of the bridge portion increases gradually to connect with the second band frame portion.