JP2882307B2 - Fluorescent display tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent display tube characterized by a structure in which a control electrode provided on a substrate in an envelope is aligned with the substrate.

[0002]

2. Description of the Related Art A fluorescent display tube has an envelope whose inside is maintained in a high vacuum state. A general envelope has a configuration in which side plates are arranged in a frame shape between outer peripheral edges of an anode substrate and a front substrate facing each other at a predetermined interval, and these plate members are integrally assembled with a sealing material. I have. In the envelope, various electrodes such as a fluorescent display unit serving as an anode, a filament-shaped cathode, and a control electrode are provided.

Some of the fluorescent display tubes having the above basic structure have a structure in which a control electrode is directly fixed on an anode substrate and connected to wiring on the anode substrate. The present inventors,
Such a structure for mounting the control electrodes is called “intermediate”.

FIG. 7 is a partially enlarged cross-sectional view of a conventional fluorescent display tube having a control electrode having an intermediate structure, and FIG. 6 is a partially enlarged plan view of the control electrode shown in FIG. A wiring conductor 2 made of a thin film of a metal such as aluminum is formed on an upper surface of an anode substrate 1 constituting an envelope of the fluorescent display tube. A black insulating layer 3 having a predetermined thickness is applied on the anode substrate 1 so as to cover the wiring conductor 2. Through-holes 4 are formed at important parts of the insulating layer 3, and an anode conductor 5 is provided on the insulating layer 3 corresponding to the through-holes 4. The anode conductor 5 and the wiring conductor 2 are connected and conductive via a conductive material 6 filled in a through hole. A phosphor layer 7 is adhered on the anode conductor 5 to constitute a fluorescent display section 8 as an anode.

[0005] As shown in FIG. 7, on the anode substrate 1,
A circular alignment mark 9 made of a thin film of the same metal as aluminum such as aluminum as the wiring conductor 2 is formed. This alignment mark 9 is covered with the insulating layer 3.

As shown in FIG. 6, the control electrode 10 having a middle structure provided above the fluorescent display section 8 has a rectangular frame section 11 and a mesh section 12 provided inside the frame section 11. doing. An annular positioning portion 13 is formed on one side of the frame portion 11. The inside diameter of the hole of the alignment portion 13 is the same as the alignment mark 9 formed on the anode substrate 1.
Slightly larger than the outline.

In positioning the control electrode 10 on the anode substrate 1 in assembling the fluorescent display tube, light is irradiated from the back side of the anode substrate 1. Since the positioning mark 9 does not transmit light and the insulating layer 3 around the positioning mark 9 is formed thin enough to transmit light, the positioning mark 9 covered with the insulating layer 3 can be visually recognized. This alignment mark 9
By positioning the positioning portion 13 of the control electrode 10 with respect to the control electrode 10, the control electrode 10 can be positioned with respect to the anode substrate 1.

[0008]

In the conventional fluorescent display tube, when positioning the control electrode 10 on the anode substrate 1, the back side of the anode substrate 1 is used to check the alignment marks 9 provided on the anode substrate 1. Had to be illuminated from Lighting equipment was expensive, and the positioning work while lighting was complicated. Also, if the insulating layer 3 is made thicker or has a two-layer structure in order to enhance the insulating property, light becomes difficult to pass,
There is a problem that the alignment mark 9 becomes difficult to see.

Further, as shown in FIG. 4, a plurality of vertically elongated mesh-like control electrodes 15 are formed in a common frame 16 by closely arranging them in a horizontal direction, as shown in FIG. If a necessary number of control electrodes 15 are integrally removed from the frame 16 according to the length of the anode display pattern in the horizontal direction of the fluorescent display tube to be applied, a large number can be obtained regardless of the length of the display unit in the horizontal direction. The control electrode 15 can be used as a common component for various types of fluorescent display tubes. The applicant of the present application has proposed a general-purpose control electrode having such excellent convenience. However, such a general-purpose control electrode is taken out of a frame according to a lateral length of a fluorescent display tube to be applied. Since the length of the control electrode differs depending on the type of the fluorescent display tube, the position of the outer edge of the cut-out control electrode naturally differs depending on the type of the fluorescent display tube. There was a problem that can not be.

An object of the present invention is to provide a fluorescent display tube having a structure in which a control electrode having a middle structure can be easily and highly accurately positioned with respect to a substrate.

[0011]

According to a first aspect of the present invention, there is provided a fluorescent display tube, comprising: an envelope; a fluorescent display portion formed on an inner surface of a substrate constituting a part of the envelope; and formed on the inner surface of the substrate surrounding the display portion insulating layer, the substrate
In the fluorescent display tube having a control electrode disposed above said a hole formed in the insulating layer, position and location mark ing a metal thin film exposed inside the hole, and the position if
A through hole reaching the substrate formed in the alignment mark.
And aligning the control electrode with the through hole.
It is characterized by:

[0014]

[Action] For through hole portion of the alignment marks to expose the interior of the hole formed in the insulating layer of the substrate fluorescent display, aligns the portion of the control electrode directly determines the position relative to the substrate of the control electrode.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the description of the embodiment with reference to the drawings, the same reference numerals as in FIGS. 6 and 7 denote the same parts in the drawings as those in the conventional fluorescent display tube. The description is omitted for the parts. The fluorescent display tube of the first embodiment will be described with reference to FIG. A hole 3a is provided in a part of the insulating layer 3 on the anode substrate 1. In the portion of the hole 3a, an alignment mark 30 made of a thin film of a metal such as aluminum is formed on the upper surface of the anode substrate 1 .

The control electrode 10 has an intermediate structure and is directly fixed on the insulating layer 3 of the anode substrate 1.

FIGS. 2 and 3 show the expansion of the alignment mark 30. FIG.
It is a large map. The alignment mark 30 provided in the hole 3a of the insulating layer 3 has an elongated rectangular shape, and a through hole 31 is formed at the center thereof. The surface of the anode substrate 1 is exposed from the through hole 31. One edge of the rectangular frame portion 11 of the control electrode 10 is aligned with the through-hole portion 31 of the alignment mark 30. The control electrode 10 has a middle structure and is directly fixed on the insulating layer 3 of the anode substrate 1.

The width of the through hole 31 of the alignment mark 30 of the second embodiment is narrower in the alignment direction than the alignment mark 20 of the first embodiment. Therefore, according to the second embodiment, the positioning accuracy of the control electrode 10 is further improved as compared with the first embodiment.

As shown in FIG.
Is an L-shape having an L-shaped through-hole portion 41, and the corners of the rectangular frame 11 are aligned with the L-shape. In this way, the positioning can be performed in two directions along the two sides of the rectangular control electrode 10 by one position, and the position of the control electrode 10 on the anode substrate 1 can be determined by one position alignment mark 40. Can be.

[0022]

According to the present invention, a through hole portion provided in the position alignment mark you exposed inside the hole formed in the insulating layer of the substrate fluorescent display, align the control electrodes directly, The following effects were obtained by adopting a structure in which the control electrode having the intermediate structure was aligned with the substrate. 1. Since it is not necessary to provide alignment marks on the control electrodes, the general-purpose control electrodes formed in a common frame by arranging a large number of mesh-like vertically long control electrodes in the horizontal direction are common to different fluorescent display tubes. It can be used as a component, eliminating the need to design individual control electrodes,
Parts cost can be reduced.

2. Positioning mark made of metal thin film
Since the through-holes can be formed with high precision, the positioning accuracy of the control electrodes is also high.

3. For alignment marks made of metal thin film
Since the through-holes are provided, they can be visually recognized without lighting from below the substrate.

4. Since the positioning through-hole is formed in the alignment mark, the alignment accuracy is high , and the insulation layer and the like formed on the substrate may be sagged, causing an error in the position of the outer peripheral edge of the alignment mark. Also, the positioning accuracy of the control electrode is not adversely affected.

[5] Positioning can be performed in two directions along two sides of the rectangular control electrode by one position, and the position of the control electrode can be determined by one position alignment mark.

[Brief description of the drawings]

FIG. 1 is a sectional view of a first embodiment.

FIG. 2 is a partially enlarged view of FIG .

FIG. 3 is a plan view of the first embodiment .

FIG. 4 is a plan view of a general-purpose control electrode in which a plurality of mesh-like vertically long control electrodes are densely arranged in the horizontal direction and formed on a common frame.

FIG. 5 is an enlarged view of a portion A in FIG.

FIG. 6 is a plan view of a conventional control electrode having an alignment pattern.

FIG. 7 is a cross-sectional view of a fluorescent display tube having a conventional alignment structure.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 anode conductor 3 insulating layer 3 a hole in insulating layer 8 fluorescent display section 10 control electrode 30, 40 alignment mark 31, 41 through-hole section

Claims (1)

(57) [Claims] An envelope, a fluorescent display portion formed on an inner surface of a substrate constituting a part of the envelope, and an insulating layer formed on the inner surface of the substrate surrounding the fluorescent display portion. , The group
In the fluorescent display tube having a control electrode disposed on the plate, said a hole formed in the insulating layer, and a position alignment mark ing a metal thin film exposed inside the hole, said alignment
Having a through-hole reaching the substrate formed in the mark,
Aligning the control electrode with the through hole.
Characteristic fluorescent display tube.