JPH0536741U - CIG fluorescent display tube - Google Patents

Abstract

(57) [Summary] [Purpose] In a CIG fluorescent display tube, the bonding wire length of the IC is secured to be sufficiently long (about 1 to 3 mm) to enable stable bonding. Especially, it is necessary when the IC shield having a sufficient width cannot be installed due to the package size restriction. [Structure] The end face of the IC shield 1 on the side closer to the display pattern is installed close to a position sufficiently close to the frame 4 (about 0.2 mm apart) without bending the end face of the IC shield 1 downward as in the conventional structure, and a bonding wire for the IC 2 is attached. 3 has a structure in which the length of 3 can be made sufficiently long (1 mm or more).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a CIG fluorescent display tube.

[0002]

[Prior Art]

 In the conventional CIG fluorescent display tube, as shown in FIGS. 3 (a) and 3 (b), a metal IC shield installed above the IC2 prevents the IC2 from malfunctioning due to the influence of light from the outside or other influences. In order to enhance the shielding effect around 1b, it was bent toward the anode substrate 5 side. The bending formed around the IC shield 1b secures a sufficient distance from the bonding wire 3 so as not to come into contact with the bonding wire 3 connecting the IC 2 and the anode substrate 5, which is installed inside the IC shield 1b. If the IC shield 1b cannot be installed with a sufficiently wide IC shield 1b due to the outer size of the CIG fluorescent display tube, it is necessary to bend the IC shield 1b and the bonding wire 3 between the IC 2 and the anode substrate 5 Therefore, the wire bond position on the anode substrate 5 side must be set to a position close to the IC 2, and as a result, there is a tendency that the length of the bonding wire 3 must be shortened. In addition, the space of the wire bond on the anode substrate 5 side was inevitably narrowed, and there was a tendency that appropriate bonding conditions could not be obtained.

[0003]

[Problems to be solved by the device]

 In this conventional CIG fluorescent display tube, the wire bond position on the anode substrate side is close to the IC in order to secure the distance between the IC shield and the bonding wire when the IC shield cannot be installed with a sufficiently wide IC shield due to the size limitation. The bonding wire length had to be shortened. When the length of the bonding wire is shortened, for example, when the horizontal distance becomes about 0.7 mm, the wire bond becomes unstable, the height of the bonding wire varies, and a bonding mistake easily occurs.

An object of the present invention is to provide a CIG fluorescent display tube which does not have a variation in the height of the bonding wire and a bonding error.

[0005]

[Means for Solving the Problems]

 The present invention is directed to an anode substrate, a display pattern including a phosphor layer formed on the anode substrate, a linear cathode stretched over the display pattern, the linear cathode and the display pattern. And a grid fixing metal frame for supporting and fixing the grid, an IC mounted on the anode substrate for driving the display pattern, and a metal IC shield for shielding the IC. In the CIG fluorescent display tube having, the one end surface of the metallic IC shield on the side of the display pattern is extended substantially parallel to the positive electrode substrate, and the end surface of the grid fixing metal frame is spaced by 0.2 mm or less. And place it.

[0006]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings.

1A and 1B are a partially cutaway perspective view and a sectional view taken along the line AA 'of the first embodiment of the present invention.

In the first embodiment, as shown in FIGS. 1A and 1B, first, the IC 2 is fixed on the insulating layer 6 formed on the anode substrate 5 with a die bonding agent 9. Each output terminal of the IC 2 is connected to the metal conductive film 10 on the anode substrate 5 via the bonding wire 3, and further connected to the phosphor layer 11 of each segment of the display pattern via the conductor layer 12. . The thermoelectrons emitted from the linear cathode 7 are accelerated by the grid 13 and then collide with the phosphor layer 11 to be converted into light energy for display.

Next, the IC 2 fixed on the insulating layer 6 is shielded by the IC shield 1. Without bending the side of the IC shield 1 close to the display pattern, it is sufficiently close to the end surface of the grid fixing metal frame (hereinafter referred to as the metal frame) 4 on the side close to the IC shield 1 (the interval is about 0.2 mm). The metal frame has the same shielding effect as the IC shield 1.

Further, since there is no downward bending of the IC shield 1 on the display pattern side, sufficient clearance is secured around the bonding wire 3, and by effectively utilizing this space, a sufficient bonding wire length can be obtained. can get.

FIG. 2 is a sectional view of a second embodiment of the present invention.

As shown in FIG. 2, the second embodiment is different from the first embodiment in that a slight downward bending (about 10 °) is applied to the side of the IC shield 1a close to the display pattern. The height of the metal frame 14 set lower than the height of the IC shield 1 and the height of the IC shield 1 on the display pattern side are formed to be substantially the same. By providing the angle portion 15 on the side of the side frame opposite to the IC shield 1, the light shielding effect on the surface of the IC 2 and other shielding effects are further enhanced.

[0013]

[Effect of the device]

 As described above, according to the present invention, in the CIG fluorescent display tube in which the IC shield cannot be set wide enough due to the limitation of the outer size, the shape of the display pattern side of the IC shield is not bent downward or slightly bent (for example, Approximately 10 degrees), and the distance between the IC shield end face on the display pattern side and the end face on the IC shield side of the display pattern and the metal frame for fixing the grid installed around it is the same as the IC shield plate thickness. Since the metal frame frame was used to shield the surface of the IC as well as the IC shield by setting it at a sufficiently close position, for example, about 0.2 mm, it was not possible to obtain it with the conventional IC shield structure. Since sufficient clearance is secured under the IC shield, there is a margin in the distance between the IC and the wire bond position on the anode substrate side. It can be, it is possible to set the bonding wire length stable length required for the bonding (about 1 to 3 mm), it has the effect that failure of the wire bonds, can be greatly reduced instability.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a first embodiment of the present invention and a sectional view taken along the line AA ′.

FIG. 2 is a sectional view of a second embodiment of the present invention.

FIG. 3 is a partially cutaway perspective view of an example of a conventional CIG fluorescent display tube and a sectional view taken along line BB ′ thereof.

[Explanation of symbols]

 1, 1a, 1b IC shield 2 IC 3 Bonding wire 4, 14 Metal frame 5 Anode substrate 6 Insulating layer 7 Linear cathode 8 Display surface glass 9 Die bonding agent 10 Metal conductive film 11 Phosphor layer 12 Conductor layer 13 Grid 15 Angle Department

Claims (1)

[Scope of utility model registration request] 1. An anode substrate, a display pattern composed of a phosphor layer formed on the anode substrate, a linear cathode stretched over the display pattern, and the linear cathode and the display pattern. A grid arranged in the middle, a grid fixing metal frame for supporting and fixing the grid, and an IC mounted on the anode substrate for driving the display pattern
And a metal IC shield for shielding the IC, wherein one end face of the metal IC shield on the side of the display pattern is extended substantially parallel to the anode substrate, and the metal frame for grid fixing is provided. A CIG fluorescent display tube, characterized in that it is arranged at a distance of 0.2 mm or less from the end face.