JPH0468736B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention comprises a glass face plate supporting a screen and a shallow dished metal rear housing in which a periodic array of heating wires is divided into segments. placed in front of the counter electrode,
The present invention relates to a flat display device, in front of which a layer of focusing wires, a layer of beam-attracting wires, a layer of beam-forming wires and a perforated anode are sequentially arranged, and a control device is provided between the anode and the face plate. .

[Prior Art] Such a flat, vacuum-sealed display device is described in West German Patent Publication No. P3541164.3. In order to obtain a planar cathode with low power consumption, the generated plate-shaped electron beam is deflected and the brightness of the individual pixels is controlled by segments of the counter electrode. For this purpose, the segments of the counter electrode run perpendicular to the lines of the screen and step with the lines to be displayed. The electron stream is taken from only one heating wire at a time.

[Problems to be Solved by the Invention] An object of the present invention is to provide a flat display device that has a robust structure and is easy to manufacture. An object of the invention is to provide a method for operating a flat display device.

[Means for Solving the Problem] The first object is that the rear housing includes a pair of opposing insulating plates and a pair of holding members, and a heating wire, a focusing wire, A frame-like support device is provided that supports the beam suction wire and the beam forming wire and is connected to the rear housing through a retaining member, and the anode and the frame are disposed between the face plate and a peripheral flange of the rear housing. The frame is achieved by a flat display supporting a control device consisting of taut wires in its frame. Also, for the second purpose, the heating wire is placed at zero potential, the beam attraction wire is given a positive voltage of 150 to 500V, and the focusing wire is placed at an absolute voltage of about two-thirds of the voltage of the beam attraction wire. A negative voltage of a value is applied to the beam forming wire, a voltage that is negative with respect to the voltage of the beam attraction wire is applied, a positive voltage of 5 to 40 V is applied to the anode, and each beam forming wire associated with the heating wire is applied. Deflection voltages are superimposed across the pair and only one heating is applied so that the line to be displayed is stepped and only the relevant segment of the counter electrode is brought to zero potential, while the other segments are given a negative voltage. This is accomplished by a method of operation in which a stream of electrons is extracted from the wire.

Examples will be described below with reference to the accompanying drawings.

[Embodiment] FIG. 1 is a sectional view of a flat vacuum-sealed display device according to an embodiment of the present invention. The face plate 1 together with a dish-shaped rear housing 2 forms a vacuum container. A fluorescent screen 3 is provided on the inner surface of the face plate 1, one line of which is visible. The rear housing 2 has a flange 1 on the periphery.
1. The frame 12 is arranged between the flange 11 and the face plate 1. The frame 12 is connected to the flange 11 and the face plate 1, for example by a sealing glass 13. The frame 12 has wires 4.1 to 4.1 acting as control device 4. I support n. The flange 11 supports the anode 5, the details of which will be described later with reference to FIG.

The rear housing 2 has a frame-like support device 14
, which supports the segmented counter electrode 6 on the bottom-facing side of the rear housing 2 . The heating wire 7, the focusing wire 8, the beam suction wire 9 and the beam forming wire 10 are supported by two opposing insulating plates 14.1 and 14.2 of the support device 14 (FIG. 2). The support device 14 includes an insulating plate 14.1
and 14.2 and a retaining member 15 arranged between them (not shown in FIG. 1 but shown in FIG. 2). The support device 14 is attached to the rear housing 2 via the holding member 15.
(not shown).

A bushing 28 is provided on the side wall of the rear housing 2, through which the terminal and wire of the counter electrode are led out. The terminal is indicated schematically at 29.

Wires 4.1 to 4. of the control device 4. n are parallel to each other and perpendicular to the scanned line of the screen 3. segments of counter electrode 6, heating wire 7, focusing wire 8, beam attraction wire 9,
and beam forming wires 10 are all parallel to each other and also to the lines of the screen 3.

FIG. 2 shows a support device 14 consisting of insulating plates 14.1, 14.2 and a holding element 15. FIG. Insulating board 1
4.1 and 14.2 are made of ceramic, especially electroceramic such as Stealan, which is commercially available (from West Germany).
Sembach, Lauf). Insulating plates 14.1 and 14.
2 is a notch 16 opened on the long edge of the insulating plate.
and 17 are provided. The heating wire 7, the focusing wire 8 and the beam suction wire 9 are subsequently arranged in the cutout 17, and the beam forming wire 10 is arranged in the cutout 16. In FIG. 2, the positions of these wires are in the
4.2 is shown only approximately in the center. Insulating board 1
The lower sides of the longer edges of 4.1 and 14.2 are provided with lugs 18 as shown in FIG. Between these lugs 18 the segments of the counter electrode 6 are connected to the insulating plates 14.1 and 14.2.
installed on. Only one segment 6.5 of the counter electrode 6 is shown in FIG. 2 to simplify the drawing. The retaining member 15 may be a plate as shown, but a rod or other similar member may also be used. The function of the retaining member 15 is to hold the insulating plates 14.1 and 14.2 in a predetermined relationship and to stabilize the support 14 against torsion.

The insulating plates 14.1 and 14.2 are connected to the contact strip 19
(only partially shown),
It supplies voltage to the wire, which is connected to it by a spring. The top contact strip 19 in FIG. 2 is connected to the odd numbered beam forming wires 10 and the next contact strip 19 is connected to the even numbered beam forming wires 10. A central contact strip 19 is connected to all beam suction wires 9. All focusing wires 8 are connected to the second contact strip 19 from the bottom. Bottom contact strip 19
are connected to all heating wires 7.

In FIG. 3, a cross-section of a part of the insulating plate 14.1 is shown in detail. The contact strip 19 is connected to the pin 21
It is attached to the insulating plate 14.1 by. A spring 20 is welded to the contact strip 19 and its free end is connected to a wire. Spring 20 is made of a conductive material. The wires are therefore electrically connected and their mechanical tension is also ensured.

FIG. 4 is a top view of anode 5, which has a perforated area 22 surrounded by a peripheral portion 23. FIG. The size of area 22 is screen 3
approximately equal to the entire area of The pores 24 in the area 22 are honeycomb-shaped. Several holes 24 are shown enlarged in the center of area 22 to clearly show the honeycomb structure. This honeycomb-like pores 24 of the anode provide a high stability, which at the same time can be reduced by 30 to 95%, e.g.
If the width of the boundary part 25 is 0.04mm and the length of the side part is
If 0.427mm is selected, a high transmission value of 90% can be obtained. Without special adjustments, the anode 5 is placed on the flange 11 of the rear housing 2 and frit-bonded by means of a sealing glass. Due to the increased temperature during the frit bonding process, the anode 5 expands and is therefore kept under tension in the display device after cooling to room temperature.

FIG. 5 is a perspective view of the frame 12 that supports the control device 4. FIG. The frame 12 is made of ceramic, especially electric ceramic such as Stealan, which is commercially available (West German
Sembach, Lauf). The frame 12 may be of monolithic construction or, as shown in FIG.
It may be assembled from 6. The frame 12 is connected to the wires 4.1 to 4. of the control device 4. I support n. In order to wrap the wire around the frame 12, the wire is continuously wrapped around the frame 12 and after the wrapping process the wire is cut on the narrow side of the rod 26 and the wire on one side is removed. .

However, a coil form can also be used, into which the frame 12 is finally inserted. The two frames are also placed on top of each other and then the wire is wrapped around them. After the wires have been cut on the narrow side of the rod 26, the wires 4.1 to 4.
Two frames with n are obtained.

Wires 4.1 to 4. n is fixed to frame 12, for example by a frit bonding process. The increased temperature during the frit bonding process causes the wire to stretch, creating a mechanical pretension in the wire when it cools to room temperature. The number of wires n is, for example, equal to the number of pixels in the line plus one.

FIG. 6 is a sectional view of a part of the flat display device.
The operation of the display device will be explained below with reference to this drawing.

For this purpose, the segmented counter electrode 6 and the heating wire 7 are assumed to be at zero potential. The heating wire 7 is energized by applying a heating voltage only during the horizontal retrace period and emits electrons during the trace period. The heating wire 7 can also be energized only during the vertical retrace period. A positive voltage in the range of 150 to 500 V is applied to the beam attraction wire 9 to accelerate the electrons towards the beam attraction wire 9. A negative voltage having an absolute value of approximately 2/3 of the voltage of the beam attraction wire 9 is applied to the focusing wire 8 . In this way, a cloud of electrons radiated by the heating wire 7 is formed, as shown in the rightmost part of the heating wire 7 in FIG. Beam forming wire 10
is applied with a voltage that is negative with respect to the voltage of the beam suction wire 9, for example, −40V. 5 to
A positive voltage in the range of 40V is supplied to the next anode 5, thus establishing a predetermined deceleration field. As a result, the electrons have a low velocity when passing through the holes 24 of the anode 5. A voltage in the range 12 to 18 kV is supplied to the screen 3. Hole 2 of anode 5
4 and the control device 4 , the plate-shaped electron beam 27 impinges on a certain line of pixels on the screen 3 .

The brightness modulation of the individual pixels in this line is carried out by wires 4.1 to 4.1 of the control device 4. This is done by a pulse width modulated voltage supplied to n. In order to deflect the plate-shaped electron beam on the screen 3 line by line,
A deflection voltage is applied between the heating wire 7 and the two associated beam-forming wires 10, which voltage is applied such that the beam successively scans across the line (moving from left to right in FIG. 6). ) changed.

If segments 6.1 to 6.6 (FIG. 6 shows only segments 6.3 to 6.5) of counter electrode 6 are connected to a voltage of -50 V, the formation of a plate-like electron beam is suppressed. be done.

During video playback, all heating wires 7 are energized as described above if the image is displayed, but the electrons to form the plate-shaped electron beam are extracted from only one heating wire at a time. be done. At first,
Electrons are extracted from a heating wire associated with the upper edge portion of the image, and a plate-like electron beam is directed in a continuous line. The electron emission from the heating wire when reaching the last line of the area covered by this electron beam is suppressed. Electrons are then extracted from the next heating wire to form the next plate-shaped electron beam. This plate-shaped electron beam is also deflected line by line until the last line of the area is reached. This advancement of the beam continues until the last heating wire reaches the bottom edge of the image.
After the last line associated with this heating wire has been drawn, the formation of this image is complete and electron extraction is switched again to the top heating wire.

FIG. 6 shows the situation in which electrons are extracted from the associated fifth heating wire to form a plate-shaped electron beam 27 for irradiating a line in the fifth area of the screen 3. FIG. Segments 6.1 to 6.
4 and 6.6 are connected to -50V. A voltage of 0V is applied to segment 6.5.
As a result, a plate-shaped electron beam 27 is formed only in this area. The deflection voltage applied between the beam forming wires causes it to impinge on the first line Z1 of the screen 3 in this area. By applying either positive or negative voltages to adjacent wires in the control device 4, the associated pixels in each line of the screen 3 will be bombarded with electrons, or the electrons will be bombarded by the anode 5. is returned in the direction of The duration of applying a positive voltage to a pair of adjacent wires belonging to one pixel determines the brightness of each pixel.

After line Z1 has been drawn, electron beam 27 is directed to line Z2 by varying the deflection voltage between beam forming wires 10. In this way, the plate-shaped electron beam 27 is sequentially deflected to the line Z.
Walk forward until you hit point 8 (indicated by the dashed line).
Next, segment 6.5 of counter electrode 6 is -50V
connected to a negative voltage, which is necessary to prevent the extraction of electrons. The voltage of the next segment 6.6 of the counter electrode 6 is then increased to 0V. Electrons are then extracted from the heating wire associated with the sixth area of the screen, forming a plate-shaped electron beam which is deflected line by line in this area as described above.

In the above example, the following terminals are required.

6 terminals for the 6 segments 6.1 to 6.6 of the counter electrode 6, 2 terminals for the heating wire 7, 1 terminal for the focusing wire 8, 1 terminal for the beam suction wire 9. one terminal for the beam forming wire 10, and two terminals for the beam forming wire 10.

A pair of beam-forming wires 10 associated with a heating wire 7 is connected in parallel with a pair of beam-forming wires 10 associated with another heating wire 7 . these
The twelve terminals are drawn out through the bushings 28 of the rear housing 2 in the usual manner.

The voltage for the anode 5 is supplied to its edge portion 23 accessible at the flange 11 of the rear housing 2. Wires 4.1 to 4. of the control device 4.
n is accessible at the edge of the frame 12 from where it can be connected to the associated control electronics. At the inner edge of the faceplate 1 there are contacts through which a high positive voltage is supplied to the screen 3.

If the terminals of all the heating wires are drawn through the bushing 28, the heating wires can also be energized individually and independently of each other. It is therefore possible to energize only those heating wires during the horizontal retrace period when they are not used to form the plate electron beam. At the same time the relevant segment of the counter electrode is connected to a voltage of -50V. In this way, a constant electrical potential is obtained along the wire producing a plate-shaped electron beam.

However, it is also possible to suppress the emission of electrons from the heating wire by supplying a positive voltage, for example 50V. In this case, the potential of the counter electrode segment need not be changed to suppress electron emission. Modulation of the plate electron beam can therefore be achieved by varying the voltage of the counter electrode segment associated with the energized heating wire. This can be used, for example, to adapt the brightness of the flat display device to the brightness of the surrounding environment.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a flat display device according to an embodiment of the present invention, and FIG. 2 is a perspective view of a support device. 3 is a partial cross-sectional view of the insulating plate of the support device of FIG. 2, and FIG. 4 is a top view of the anode. FIG. 5 is a perspective view of the wires and frame of the control device, and FIG. 6 is a partial cross-sectional view of the display device. DESCRIPTION OF SYMBOLS 1... Face plate, 2... Rear housing, 3... Screen, 4... Control device, 5...
Anode, 6... Counter electrode, 7... Heating wire, 8... Focusing wire, 9... Beam attraction wire, 10... Beam forming wire, 12... Beam forming wire, 14... Support device, 14.1 ,1
4.2... Insulating plate, 16... Holding member, 16,1
7... Notch portion, 19... Contact band, 20... Spring.

Claims (1)

[Claims] 1. A screen comprising a glass face plate supporting a screen and a shallow dish-shaped metal rear housing,
a periodic array of heating wires is disposed in front of a segmented counter electrode, in front of which a layer of focusing wires, a layer of beam-attracting wires, a layer of beam-forming wires, and a perforated anode are sequentially disposed; In a vacuum-sealed flat panel display having a control device between an anode and a faceplate, the rear housing includes a pair of opposing insulating plates and a
a frame-shaped support device comprising a pair of holding members, supporting a heating wire, a focusing wire, a beam suction wire, and a beam forming wire between the pair of insulating plates, and coupled to the rear housing via the holding members; an anode and a frame are disposed between the face plate and the peripheral flange of the rear housing;
Flat display device, characterized in that the frame supports a control device consisting of tensioned wires on the frame. 2. The flat display device according to claim 1, wherein the insulating plate is made of ceramic material. 3. Claim 3, characterized in that the insulating plate has an open cutout on its long edge, in which heating wires, focusing wires, beam suction wires and beam forming wires are arranged. 2. The flat display device according to item 2. 4. Claims characterized in that the insulating plate is provided with a contact strip on the side facing the rear housing, to which heating wires, focusing wires, beam suction wires and beam forming wires are connected via springs. The flat display device according to item 3. 5. The flat display device according to claim 4, wherein each insulating plate has a conductive coating on the inside thereof. 6. The insulating plate supports counter electrodes on the side facing the bottom of the rear housing, the longitudinal axes of the segments of the counter electrodes being parallel to the lines of the screen. flat display device. 7. Flattening according to claim 6, characterized in that the width of the segment is equal to the width of the area on the faceplate described on the faceplate by the plate beam deflected by the beam-forming wire. Display device. 8. The flat display device according to claim 1, wherein the anode is in close contact with the honeycomb pores. 9. The flat display device according to claim 1, wherein the frame is made of ceramic material. 10. The flat display device according to claim 9, wherein the frame is composed of four rod-shaped bodies. 11. Flat display device according to claim 1, characterized in that the wires of the control device supported by the frame run perpendicularly to the lines of the screen and are associated with the pixels of the line. 12. In the method for operating a flat display device according to any one of claims 1 to 11, the heating wire is placed at zero potential, and the beam attraction wire is applied with a positive voltage of 150 to 500 V. , the focusing wire has a voltage of about 3 the voltage of the beam attraction wire.
A negative voltage of two times the absolute value is applied to the beam forming wire, a voltage that is negative with respect to the voltage of the beam attraction wire is applied, and a positive voltage of 5 to 40 V is applied to the anode, associated with the heating wire. A deflection voltage is superimposed across each pair of beam-forming wires to step the line to be displayed, so that only the relevant segment of the counter electrode is brought to zero potential, while the other segments are given a negative voltage. A method of operation characterized in that the electron stream is taken from a single heating wire. 13. Method according to claim 12, characterized in that only those heating wires whose associated segments of the counter electrode are connected to a negative voltage are energized. 14. The radiation by the heating wire is suppressed by supplying a positive voltage and the plate-like electron beam produced is modulated by changing the voltage of the segment of the counter electrode belonging to the energized heating wire. Claim 12, characterized in that
The method described in section.