JP6068066B2 - Fluorescent display device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a fluorescent display device (VFD), and more particularly to a fluorescent display device that enables a thin structure and a method for manufacturing the same.

  Display elements such as home appliances, measuring instruments, medical devices, and in-vehicle displays, display elements that display a predetermined pattern or graphic, various light sources such as backlights, printer heads, and light sources for copiers, and fluorescence on flat-screen televisions Display devices (fluorescent display tubes) are frequently used. In the fluorescent display device, a vacuum container is configured by a substrate arranged in parallel to each other, a translucent flat plate portion (front plate), and a rectangular frame-shaped peripheral wall portion (spacer member) positioned therebetween, A plurality of phosphor layers provided on each of a plurality of anodes (anodes) on the display surface of the substrate in a vacuum vessel, and both ends of the phosphor layer are supported by anchors and supports above the display surface. And the electrons generated from the filamentary cathode in a vacuum space are controlled by a grid electrode provided between the phosphor layer and the filamentous cathode, thereby controlling the phosphor layer. It has a structure for selectively emitting light.

  The fluorescent display device is provided with a getter for forming a vapor deposition film that adsorbs an internal residual gas on an inner surface of a front plate or the like. The getter is, for example, one in which a nickel ring-plated iron ring-shaped container is filled with a getter agent made of a mixture of an aluminum-barium alloy and nickel. In the manufacturing process of the fluorescent display device, the substrate, the front plate, and the spacer member are hermetically sealed together to form a vacuum container, and after evacuating from the inside, the getter is heated by high-frequency induction or the like. Evaporation (getter flash) is performed to form a deposited film made of, for example, an aluminum-barium alloy. Therefore, the getter is on the upper side of the filamentary cathode so that the vapor deposition film formed on the front plate located on the viewer side does not interfere with the display by spreading to the display area when the getter agent evaporates, It is arranged at a height position near the inner surface of the front plate.

  The getter is supported by a getter support portion that is integrally formed (cut and raised) or joined as a separate member to a metal frame on which an anchor, a support, or the like that supports the filamentary cathode is formed. An example of a conventional metal frame structure is shown in FIG. As shown in FIG. 4, a getter support portion 22 is formed integrally with a part of the metal frame 21. The getter support portion 22 includes a getter shield 22a and a getter ribbon 22b. The getter shield 22a is bent substantially perpendicular to the front plate 25 side (front side) of the metal frame 21, and the getter ribbon 22b is bent substantially perpendicular to the getter shield 22a, and the getter 23 is fixed to the getter ribbon 22b. Has been. As shown in the side view of the VFD, the metal frame 21 is installed on the substrate 26. The getter 23 does not interfere with the filamentary cathode 24 and prevents the vapor deposition film from spreading to the display area of the front plate 25, so that the getter support portion 22 is above the filamentary cathode 24 (near the front plate 25). Is arranged.

  In the fluorescent display device having such a structure, it is possible to suppress thermal deformation of the metal frame caused by the getter flash, and as a composite part integrally provided with the metal frame and the getter support portion, A fluorescent display device has been proposed in which an intermediate portion with a getter support portion is disposed on a substrate so that the intermediate portion is located outside the vacuum vessel, the substrate and the peripheral wall portion are sealed, and then the composite part is cut at the intermediate portion. (See Patent Document 1).

  In addition, a transparent conductive film (nesa film or ITO film) is provided on the inner surface of the front plate serving as the display unit of the fluorescent display device to block the influence of an external electric field, and a cathode or grid potential is applied to the transparent conductive film. It is known to shield. In order to apply a potential to the transparent conductive film, a nesa contact is vertically attached to the metal frame, and this nesa contact extends from the metal frame on the substrate side to the inner wall of the front plate to make electrical contact.

  In addition, the fluorescent display device includes an IC (semiconductor element) for controlling light emission display. Fluorescent display devices with built-in semiconductor elements can eliminate the need for external lead lines, and can be downsized as a whole and display density can be improved. However, external light, electrons emitted from filaments, deposition of evaporating substances, etc. In order to prevent malfunction due to the above, it is necessary to provide a shielding portion in the semiconductor element. In this case, the shielding part becomes a dead space, and the outer dimension of the fluorescent display device is increased only by this part. In order to solve this problem, conventionally proposed are those in which a convex narrowing part is formed on a metal frame (see Patent Document 2), and a metal frame formed in a bridge shape on a substrate (see Patent Document 3). Has been.

  In addition, as a device capable of realizing a wide display area, a fluorescent display device in which an external lead pin is a so-called hanging type has been proposed (see Patent Document 4).

JP 2000-208049 A JP 2004-134149 A JP-A-8-31351 JP 2005-190883 A

  However, in the fluorescent display devices (fluorescent display tubes) of Patent Documents 1 to 3, since the getter is disposed at a position higher than the filament cathode, the height (tube thickness) of the fluorescent display tube is increased. There is. In order to reduce the tube thickness, it is necessary to increase the vertical dimension (B dimension) of the fluorescent display tube. In addition, since these fluorescent display devices are provided with a metal frame on the substrate, it is necessary to secure the length of the nesa contact so that sufficient contact can be made with the inner wall of the front plate.

  On the other hand, the fluorescent display device of Patent Document 4 can solve the problem of Nesa contact by installing a metal frame on the front plate side, but the getter is a substrate rather than a filament cathode as in Patent Documents 1 to 3. It is arranged at the position on the side (high position as seen from the frame), and it is difficult to reduce the tube thickness by this getter arrangement.

  Further, in the fluorescent display device of Patent Document 3, the filament height can be adjusted without changing the height of the leaf spring of the anchor member. However, when it is desired to shorten the distance between the phosphor and the filament (P-Kgap), it is necessary to design a molding die for the bridge-shaped metal frame each time, which increases the manufacturing cost. In the case of Patent Document 4, it is necessary to adjust the phosphor-filament distance (P-Kgap) in consideration of the arrangement position of the getter, and the getter support portion is integrally formed on the metal frame. As in Patent Document 4, the design of the molding die is necessary.

  The present invention has been made to cope with such problems, and can reduce the size of the entire display device while avoiding interference between the getter and the filamentary cathode, and without newly designing a frame molding die. An object of the present invention is to provide a fluorescent display device capable of shortening the distance between the phosphor and the filament and a method for manufacturing the same.

  The fluorescent display device of the present invention includes a vacuum vessel in which a front plate and a substrate are sealed and bonded via a spacer member, an anode and a phosphor layer provided on the substrate in the vacuum vessel, and the phosphor A filamentary cathode laid above the layer, a pair of frames formed with a stretch portion over which the filamentary cathode is stretched, a getter supported by the frame, the phosphor layer, and the filamentous cathode A pair of frames arranged along the front plate, a part of which is sandwiched between the front plate and the spacer member. And at least one of the pair of frames has a getter support portion that supports the getter on the substrate side of the frame, and the getter support portion provides the getter support portion. Terpolymer is characterized in that it is supported between the said frame and the filament cathode.

  The getter support portion is formed by bending a protrusion formed integrally with the frame substantially vertically to the substrate side, and then the height of the vertical portion becomes an intermediate position between the frame and the filament cathode. It is configured to be bent at a height and substantially perpendicular to the frame side, and the getter is supported by a tip portion thereof.

  The method for manufacturing a fluorescent display device according to the present invention is the method for manufacturing the fluorescent display device according to the present invention, wherein the getter is fixed to the getter support portion at a position where the getter does not interfere with the filamentary cathode, and then the getter support portion. And the getter is placed so as to be embedded between the frame and the filamentary cathode.

  The fluorescent display device of the present invention includes a vacuum vessel in which a front plate and a substrate are sealed and bonded via a spacer member, an anode and a phosphor layer provided on the substrate in the vacuum vessel, and the phosphor layer Arranged between the phosphor layer and the filamentous cathode, a filamentary cathode laid above, a pair of frames formed with a stretched portion over which the filamentary cathode is stretched, a getter supported by the frame The pair of frames is disposed along the front plate, and a part of the pair of frames is sandwiched and fixed between the front plate and the spacer member. One has a getter support portion for supporting a getter on the substrate side of the frame, and the getter is supported between the frame and the filamentary cathode by the getter support portion. In, while avoiding the interference of the filament cathode and getter, space-saving in the fluorescent display device can be reduced in size (in particular wall thickness) of the entire display device.

  Further, since the frame is fixed to the front plate side and the getter is housed between the frame and the filamentary cathode, the phosphor-filament distance (P-Kgap) is the height of the spacer member. It will be adjustable only. For this reason, the distance between the phosphor and the filament can be shortened without designing a new frame molding die.

  Further, since the frame is fixed to the front plate side, the Nesa contact can be easily brought into contact with the inner wall of the front plate with a minimum length. Further, contact with the IC can be avoided without forming the frame into a bridge shape.

  In the method of manufacturing the fluorescent display device of the present invention, after the getter is fixed to the getter support portion at a position where the getter does not interfere with the filament cathode, the getter support portion is deformed and the getter is submerged between the frame and the filament cathode. Since it is arranged, it is excellent in workability and can be manufactured with the same number of steps as the conventional frame manufacturing steps.

It is the front view and sectional drawing of the fluorescence display apparatus of this invention. It is a figure which shows the structure of the getter support part of a flame | frame. It is a figure which shows a getter attachment process. It is a figure which shows the structure of the getter support part of the conventional frame.

  An example of the fluorescent display device (fluorescent display tube) of the present invention is shown in FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view as viewed from the short side. In the fluorescent display tube 1, a front plate 2 and a substrate 3 are sealed and bonded at a sealing portion 13 via a spacer member 4 to constitute a vacuum container. The front plate 2 is made of a light-transmitting cover / glass plate, the substrate 3 is made of an insulating material such as glass, ceramics, or a bag, and the spacer member 4 is made of a frame-like glass material or the like. . The front plate 2 and the substrate 3 are glass-sealed to each other at the sealing portion 13 via the spacer member 4 to form a long flat box-like airtight vacuum container, and the inside thereof is surrounded by these members. A vacuum space is formed.

  The fluorescent display tube 1 is provided with an anode 5 formed of an anode electrode and a phosphor layer formed on the anode electrode on a substrate 3 in the vacuum vessel. The anode 5 is installed above the phosphor layer. A filamentary cathode 6, and a mesh grid 7 disposed between the phosphor layer and the filamentous cathode 6. A plurality of anodes 5 composed of an anode electrode and a phosphor layer constitute a light emitting unit for displaying characters, symbols, etc., and function as a display surface of the fluorescent display tube 1. The anode 5 is surrounded by a mesh grid 7 provided for each light emitting unit. The anode 5 and the mesh grid 7 are electrically connected when the electrode pad 8 formed via the wiring pattern in the substrate 3 and the tip of the external lead pin 9 are in contact with each other. The external lead pin 9 is sandwiched and sealed between the front plate 2 and the spacer member 4.

  In addition, the fluorescent display tube 1 is provided with an exhaust pipe and exhaust holes (not shown) for exhausting in the exhaust / sealing process at the time of manufacture. In addition, a transparent conductive film (not shown) is provided on the inner surface of the front plate 2 serving as a display unit of the fluorescent display device in order to block the influence of an external electric field.

  At both ends of the front plate 2 inside the vacuum vessel, a pair of frames 10 and 10 ′ are provided which are fixed by being sandwiched and sealed between the front plate 2 and the spacer member 4. In this structure, the frame 10 is installed on the front plate 2 side. Since the frame 10 is installed on the front plate 2 side, a nesa contact for electrically conducting the frame and the transparent conductive film can be brought into contact with the front inner wall with a minimum length. Further, contact with the IC on the substrate 3 can be avoided without forming the frame in a bridge shape.

  The frames 10 and 10 'are metal frames made of, for example, 426 alloy (Ni42, Cr6, balance Fe). Between the frames 10 and 10 ′, a thin filamentary cathode 6 functioning as a directly heated cathode is parallel to the longitudinal direction of the substrate 3 and is spaced above the display surface of the substrate 3 above the mesh grid 7. It is stretched to be at the height position. The filamentary cathode 6 is made of, for example, a tungsten wire having a surface coated with an alkaline earth metal oxide solid solution having a low work function such as (Ba, Sr, Ca) O as an electron emission layer.

  The pair of frames 10 and 10 'serve as a stretched portion over which the filamentary cathode 6 is stretched, and an anchor that elastically supports the filamentous cathode 6 in one frame and inelastically supports it in the other frame. Each support is formed. Both ends of the filamentary cathode 6 are fixed to the anchor and the support by welding or the like. Anchors and supports can be integrated with the frame by forming another member such as SUS430 into a predetermined shape by bending with a press and then fixing it to the frame by spot welding or by directly bending the frame. Can be formed.

  The frame 10 has a getter support portion 12 that supports the getter 11 on the substrate 3 side (back side). The getter 11 is supported between the frame 10 and the filamentary cathode 6 by the getter support portion 12. The getter support portion 12 may be provided on any one of the frames, or may be provided on the frame 10 'side. Further, the getter support 12 can be formed at any position in each frame as long as the getter 11 can support the getter 11 between the frame and the filamentary cathode. In FIG. 1, it is formed on the lead pin side (upper side) of the frame 10, but it may be formed on the opposite side (lower side).

  The structure of the getter support portion 12 will be described in detail with reference to FIG. FIG. 2 is a side view of the structure of the frame getter support (before and after molding) and the fluorescent display tube when this support structure is used. A getter support portion 12 is integrally formed as a projecting portion on a part of the frame 10. The getter support portion 12 includes a getter shield 12a and a getter ribbon 12b. The getter shield 12a is bent substantially perpendicular to the substrate 3 side (back side) of the frame 10, and the getter ribbon 12b is bent substantially perpendicular to the getter shield 12a. The getter 11 is fixed to the getter ribbon 12b. Yes. The width of the getter shield 12 a is half of the distance between the frame 10 and the filamentary cathode 6. For this reason, the protruding portion constituting the getter support portion 12 has a height at which the height of the vertical portion (getter shield 12 a) bent substantially vertically from the frame 10 is an intermediate position between the frame 10 and the filamentary cathode 6. Thus, it is further bent substantially vertically to the frame 10 side. The getter ribbon 12b is a part that is finally bent, and is a tip part of a protruding part.

  The width of the getter shield 12a (the height when bent) may be a height that can finally prevent the getter 11 from physically interfering with the filamentary cathode 6. For example, as described above, the width of the getter shield 12a is set to be half of the distance between the frame 10 and the filamentary cathode 6 so that contact between the getter 11 and the filamentous cathode 6 is avoided after the getter 11 is attached. be able to. Similarly, the bending of each part is not limited to a completely vertical bending as long as the getter 11 can finally avoid physical interference with the filamentary cathode 6. .

  As shown in the side view of the VFD, the frame 10 is installed on the front plate 2 side. The getter 11 is not in direct contact with the filamentary cathode 6 and does not physically interfere. The vapor deposition film by the getter 11 is formed in a portion that does not interfere with the anode 5 or the like on the substrate 3 side. Further, a part of the evaporated material by the getter 11 is also deposited on the filamentary cathode 6 but does not adversely affect the display quality.

  Since the getter 11 is supported between the frame 10 and the filamentary cathode 6, space saving in the fluorescent display tube can be achieved while avoiding interference between the filamentous cathode 6 and the getter 11, and the size of the entire display device can be reduced. Can be small. In particular, since the frame 10 is installed on the front plate 2 side and the getter 11 is housed between the frame 10 and the filamentary cathode 6, this is an important factor in the luminance design of the fluorescent display device. The phosphor-filament distance (P-Kgap) can be adjusted only by the height of the spacer member 4, and P-Kgap can be shortened without designing a new frame molding die.

  In the fluorescent display device of the present invention, a process of attaching the getter to the getter support portion will be described with reference to FIG. 3 is an enlarged view of the getter support portion in FIG. 2, and shows a frame surface opposite to that in FIG. As shown in FIGS. 3A and 3B, first, the getter 11 is fixed to the getter ribbon 12 b of the getter support portion 12 at a position where it does not interfere with the filamentary cathode 6. The procedure for bending the getter shield 12a and the getter ribbon 12b in the getter support 12 is the same as that in FIG. Next, from the state of FIG. 3B, the getter 11 is pushed downward in the figure, and a part of the getter support portion 12 is plastically deformed and placed between the frame 10 and the filamentary cathode 6. To do. In the fluorescent display device of the present invention, a manufacturing process other than the getter mounting process can employ a manufacturing process in a normal fluorescent display device.

  By manufacturing according to the above process, the getter can be easily arranged without interfering with the filamentary cathode from folding to getter fixing, and the workability is excellent. And finally, by arranging the getter between the frame and the filamentary cathode, the space in the fluorescent display device can be saved. Note that, as described above, even in this state, the evaporated material from the getter only contacts the filamentary cathode, and the getter and the filamentous cathode do not physically interfere with each other.

  In the above-described embodiment, the getter support portion of the fluorescent display device according to the present invention is described as being formed integrally with the frame. However, the present invention is not particularly limited thereto. For example, in the aspect in which the frame is installed on the front plate, if the getter is supported between the frame and the filamentary cathode, the getter support portion formed as a separate member from the frame is joined by welding or the like. May be.

  The fluorescent display device of the present invention can reduce the size of the entire display device while avoiding interference between the getter and the filamentary cathode, and can shorten the distance between the phosphor and the filament without designing a new frame mold. Therefore, as a display element for displaying a predetermined pattern or graphic on a display unit such as a home appliance, a measuring instrument, a medical device, or a vehicle-mounted display, it can be suitably used particularly in a thin and small application.

DESCRIPTION OF SYMBOLS 1 Fluorescent display tube 2 Front plate 3 Board | substrate 4 Spacer member 5 Anode 6 Filament-like cathode 7 Mesh grid 8 Electrode pad 9 Lead pin 10, 10 'Frame 11 Getter 12 Getter support part 13 Sealing part 21 Metal frame 22 Getter support part 23 Getter 24 Filamentary cathode 25 Front plate 26 Substrate

Claims (3)

A vacuum vessel in which the front plate and the substrate are sealed and bonded via spacer members, an anode and a phosphor layer provided on the substrate in the vacuum vessel, and the front plate side above the phosphor layer A pair of frames in which a filamentary cathode laid on the substrate, a pair of stretched portions over which the filamentary cathode is stretched, a getter supported by the frame, and between the phosphor layer and the filamentous cathode A fluorescent display device comprising an arranged grid,
The pair of frames are arranged along the front plate, a part of which is sandwiched and fixed between the front plate and the spacer member,
At least one of the pair of frames has a getter support portion that supports the getter on the substrate side of the frame, and the getter has entered between the frame and the filamentary cathode by the getter support portion . A fluorescent display device characterized by being supported in a state .   The getter support portion is formed by bending a protrusion formed integrally with the frame substantially perpendicularly to the substrate side, and then the height of the vertical portion becomes an intermediate position between the frame and the filament cathode. 2. The fluorescent display device according to claim 1, wherein the getter is supported by a tip end portion of the frame, wherein the getter is bent at a height and substantially perpendicular to the frame side. A method of manufacturing a fluorescent display device according to claim 1 or 2,
After the getter is fixed to the getter support portion at a position where it does not interfere with the filamentary cathode, the getter support portion is deformed and the getter is placed between the frame and the filamentary cathode. A method for manufacturing a fluorescent display device.

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