JPH03201352A - Fluorescent material dot array tube - Google Patents

Abstract

PURPOSE:To obtain a highly reliable fluorescent material dot array tube in which luminous brightness is not lowered and luminous nonuniformity is not produced by providing a luminous segment electrode, metal wiring on a substrate surface, and a contact prevention layer Preventing the contact with the luminous segment electrode and the metal wiring. CONSTITUTION:A conductive material is sticked to a substrate 20 surface to form a conductive thin film layer, and then a strip-like Al wiring pattern (luminous segment electrode) 21 is formed. Also a contact prevention layer 28 composed of SiO2 film, etc., is formed between the luminous segment electrode 21 and an insulation layer 24. Consequently the Al wiring pattern 21, etc., is not corroded by the insulation layer 24 or external water and other dirt, etc. Moreover because the prevention layer 28 is an insulation substance structurally and it is needed to select one not including impurities such as alkali ion, etc., for example a SiO2 film is used, and at the time of Al wiring, a film is formed using low-temperature plasma CVD. This permits obtaining a dot array tube in which luminous brightness is not lowered and luminous nonuniformity is not produced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a phosphor dot array tube used in bar code display tubes, optical writing device devices of optical printers, and the like.

[Prior Art] An example in which a phosphor dot array tube is used in an optical printer is shown in FIG. 3, and an outline of its operation will be explained.

First, the phosphor dot array tube 3 is charged in accordance with a zero image signal to uniformly charge the photoreceptor drum l by the charger 2.
An electrostatic latent image is formed on the photosensitive drum l by irradiating the photosensitive drum l with an image formed by emitting light dot by dot using the lens array 4. The static latent image is turned into a visible image by the adhesion of toner by the developing device ff15. Thereafter, the visible image is transferred to a transfer paper 10 by a transfer charger 6.The transfer paper 10, which is peeled off from the photosensitive drum 1 by a zero-separation charger 7, is fixed with toner by a fixing device 11.

On the other hand, after the transfer, the photosensitive drum 1 is neutralized by the static eliminating lamp 8, and then brought into a state where it can be charged again by the cleaning device 9.

Next, FIGS. 4 and 5 show an exploded perspective view and a sectional view, respectively, of the phosphor dot array tube 3 used in the optical printer.

In FIGS. 4 and 5, 20 is a rectangular substrate made of glass, ceramic, or the like. The group Fi, 20 has t-poles arranged in a staggered manner from its side ends toward the center. A phosphor 23 is adhered to the tip surface of the electrode, and this adhered electrode is used as a light emitting segment as a pole 21. Further, the phosphors 23 are arranged in a dot shape in a straight line.

A mesh-like grid 25 having a honeycomb structure with a constant thickness is installed on the surface of the end portion of the substrate of the light emitting segment electrode 21 with an insulating layer 24 interposed therebetween. The grids 25 extend along both sides of the substrate 20 in the longitudinal direction, and are arranged to sandwich the phosphors 23 at regular intervals. A pair of hot cathodes 27 are suspended along the longitudinal direction of the substrate 20 in an internal space kept in a vacuum by the face glass 26 . Thermionic electrons generated from the hot cathode 27 generate light emitting segment electrons [! 21 is in a positive potential state with respect to the cathode center potential, acceleration is controlled when passing through the grid 25, and then it is attracted to the light emitting segment electrode 21,
Excite the energy of the fluorescent substance and cause it to emit light.

[Problems to be Solved by the Invention] When a phosphor dot array tube is used in the optical writing section of the optical printer shown in FIG. It will be connected to the IC driver. The light-emitting segment must maintain a constant electrical conductivity and must not change over time. The insulating layer 24 used in conventional fluorescent display tubes is formed by a method such as screen printing so as to directly cover the light-emitting segment electrodes 21 made of A42 or the like and other wiring, but this insulating layer 24 is aRbt whose main component is lead
It is made of acid glass and is highly corrosive due to the presence of impurities such as alkali ions.
It may corrode and deteriorate A21 and other metal wiring.

In addition, when the insulating layer 24 is formed by screen printing to form a thick film of several tens of micrometers and then baked in the air at about 550 to 600°C, the AfL A problem arises in that the electrodes are corroded and the electrical conductivity decreases over time.

If it is used as a fluorescent display tube, the density of the metal wiring is small, and reliability such as moisture resistance is not a problem. Since it is necessary to drive each dot, the density of metal wiring is high, and moisture resistance must also be taken into consideration for the reliability of the device.

An object of the present invention is to provide a highly reliable phosphor dot array tube that has a structure in which the above-mentioned corrosion does not occur over time, and that does not reduce luminance brightness or cause uneven luminescence. There is a particular thing.

[Means for Solving the Problems J] In order to achieve the above object, the present invention provides a light-emitting segment electrode formed by coating and adhering a phosphor to a part of the surface of a strip-shaped electrode installed on a substrate; a hot cathode; and a grid placed between the light emitting segment electrode and the hot cathode and insulated from the light emitting segment electrode by an insulating layer; In the phosphor dot array tube, the phosphor dots emit light by causing the phosphor to emit light by controlling the acceleration of the phosphor by the grid and causing it to collide with the light emitting segment electrode, wherein the insulating layer and the light emitting segment tI'! and a contact prevention layer that prevents contact with metal wiring on the surface of the substrate.

[Function] According to the present invention, the 2-contact prevention layer prevents the A.degree. C. wiring pattern from being corroded by conventional insulating layers, external moisture, and other contaminants.

[Example] Hereinafter, five aspects of the present invention will be explained in detail.

FIG. 1 is a sectional view of an example of a phosphor dot array tube according to the present invention. In this figure, the same parts as in Figure 5 include:
The same reference numerals are given and the description thereof will be omitted. The feature of this embodiment is that the light emitting segment is formed by using Si between the pole 21 and the insulating layer 24.
This is because a contact prevention layer 28 made of a 0g film or the like is formed.

Figure 2 shows the manufacturing process of the phosphor dot array tube.

The difference between the manufacturing process of this embodiment and the conventional manufacturing process is that a contact prevention layer forming process 5 is performed before the insulating layer forming process 52.
1 was added.

In the electrode forming step 50, first, a conductive thin film layer is formed by depositing a conductive material on the surface of the substrate 20 by a method such as sputtering.

Generally, from the viewpoint of cost, a strip-shaped Afl wiring pattern (corresponding to a positive electrode) is formed by a normal photolithography method using 0th order using 8β.

The contact prevention layer forming step 51 includes the conventional insulating layer 24 and the above! [! This step is for providing a layer to separate the wiring pattern from the wiring pattern provided in the formation step 50. The contact prevention layer 28 is an insulator in its structure, and it is necessary to select a layer that does not contain impurities such as alkali ions.For example, a SiO* film can be used, and in the case of Aff wiring, it can be formed by low-temperature plasma CVD. The film is formed using This is because at high temperatures, the grain boundaries of Al1 move, resulting in many protrusions such as heelocks. Patterning is performed using a normal photolithography method, and the size of the pattern is made larger than a normal insulating layer forming area. This is because if it is too small, the W124 and the AJ2 wiring (later the light emitting segment electrode 21) will come into contact with each other. On the contact prevention layer 28 provided in this way, the insulating layer 2 is printed by screen printing or the like in the same manner as in the conventional method.
After forming the phosphor 4, the phosphor 23 is deposited in a dot shape on the β wiring (anode as the pole) in a line to form a tube.
A phosphor dot array tube having light emitting segment electrodes 1421 as shown in FIG. 1 can be constructed.

Note that the formation method and structure of the contact prevention layer 28 are just one example, and any layer that substantially prevents contact between the insulating layer 24 and the light emitting segment electrode 21 and the metal wiring on the surface of the substrate can be used. Not particularly limited.

[Effect of the invention] As explained above, according to the present invention, the control
By having the h layer, the structure is such that the Al and wiring patterns are not corroded by conventional insulating layers, external moisture, and other contaminants, so the variation in luminance of the phosphor after tube formation is small. Therefore, partial reduction in brightness due to the AI2 wiring over time is suppressed, and it can be used satisfactorily for optical writing in an optical printer.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a phosphor dot array tube showing an embodiment of the present invention, Fig. 2 is a view showing an example of the manufacturing process of the phosphor dot array tube of the present invention, and Fig. 3 is a cross-sectional view of a phosphor dot array tube according to an embodiment of the present invention. A diagram showing a schematic configuration of an optical printer as an example,
FIG. 4 is an exploded perspective view of a conventional phosphor dot array tube in an arrangement state, and FIG. 5 is a sectional view of the conventional phosphor dot array tube. 20-.Substrate, 21-Light emitting segment electrode, 23-.
phosphor, 24-insulating layer, 25-grid, 26-face glass, 27-hot cathode, 28-contact barrier layer. Form 4 Illusion χ v) ZID Aσ Illusion,? Money 4 illusion

Claims (1)

[Scope of Claims] A light-emitting segment electrode formed by coating and adhering a phosphor to a part of the surface of a strip-shaped electrode installed on a substrate; a hot cathode; and a combination of the light-emitting segment electrode and the hot cathode. placed between
a grid disposed insulated from the light emitting segment electrode by an insulating layer, the thermoelectrons emitted from the hot cathode are accelerated and controlled by the grid and made to collide with the light emitting segment electrode; A phosphor dot array tube adapted to emit light from a phosphor, comprising a contact protection layer for preventing contact between the insulating layer and the light-emitting segment electrode and metal wiring on the surface of the substrate. Body dot array tube.