JP3733325B2 - Support device and display device using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a support device and a display device using the same, and for example, a shield structure for reducing unnecessary radiation noise of a display device such as a television or a display having a matrix drive type flat display panel, particularly improvement of characteristics in a high frequency region of noise. It is about the structure which aimed at.
[0002]
[Prior art]
In a display device having a conventional matrix-driven flat display panel, for example, a plasma display panel display device, matrix pixels are formed on the flat display panel.
[0003]
Hereinafter, a conventional plasma display panel (hereinafter referred to as PDP) display device will be described with reference to the drawings. FIG. 12 is a perspective view for explaining a configuration of a conventional PDP, and FIG. 13 is a perspective view for explaining an electrode structure of the conventional PDP. A chassis 11 that is a holding plate is disposed on the non-display surface side of the PDP panel 10 made of a glass substrate or the like, and the PDP panel 10 is held by the chassis 11. The chassis 11 is a conductive metal plate made of an aluminum-based material. The chassis 11 functions as a frame ground (hereinafter referred to as FG) in terms of electrical circuit, and is disposed on the rear glass substrate 24 of the PDP panel 10. It functions as an electrode ground which is the ground surface of the electrode 14 of the panel 10.
[0004]
The driver drive circuits 13a and 13b are disposed on the rear side of the chassis 11, and signals generated from the driver drive circuits 13a and 13b are transmitted to the electrodes 14 of the PDP panel 10 by the flexible cable 15. The signal ground (hereinafter referred to as SG) of the scan / sustain electrode driver drive circuit 13a is grounded at points B and B ′, and the SG of the write electrode driver drive circuit 13b is grounded at the points C and C ′ and the chassis 11 as FG. The chassis 11 which is the FG and electrode ground functions as a drive circuit feedback ground which is a ground plane through which the feedback currents of the driver drive circuits 13a and 13b flow.
[0005]
In the PDP panel 10, a sustain electrode 14a and a scan electrode 14b are provided on the front glass substrate 20 on the display surface side, a write electrode 14c is formed on the opposite rear glass substrate 24, and plasma discharge is adjacent between the write electrodes 14c. A separation wall 22 is formed so as not to affect the electrodes. Red 23a, blue 23b, and green 23c phosphors are separately coated on the writing electrode 14c, and a discharge gas is sealed in a discharge space between the front glass substrate 20 facing the display surface and the rear glass substrate 24. The cells selected by the driver drive circuits 13a and 13b undergo plasma discharge, and the red 23a, blue 23b, and green 23c phosphors emit light, thereby forming a color image. In FIG. 13, reference numeral 21 denotes a dielectric layer.
[0006]
However, when the above-mentioned PDP is examined for items of unnecessary radiation of radio waves based on the standards of the Voluntary Control Council for Interference by Information Processing Equipment (VCCI), the sustain electrode 14a and the scan electrode 14b have a voltage of 100 Vp-p to 200 Vp- A signal having a pulse voltage of p is applied, and a signal having a pulse voltage of 30 Vp-p to 100 Vp-p is applied to the write electrode 14c, and electromagnetic interference waves such as the fundamental wave and harmonics thereof are emitted into the air. For this reason, there is a problem that the level of unnecessary radiation noise is large and other electronic devices are adversely affected electromagnetically.
[0007]
Further, the high-frequency component that generates the electromagnetic interference wave flows through the chassis 11 that is an FG, and the numerical analysis result of FIG. 14 is caused by the stray capacitance between the chassis 11 and the stand 12 that are electrically separated. As shown in FIG. 4, since the high frequency current loop 41 is formed and electromagnetic interference waves are radiated in the air, the level of unnecessary radiation noise is increased. In numerical analysis, noise is fed to the chassis, electromagnetic analysis is performed by the moment method, and the analysis model is divided into about 3000 elements. In FIG. 14, 40 is a current vector.
[0008]
As a solution to this problem, as shown in FIGS. 15 and 16, a conductive metal casing 30 made of aluminum and a conductive film or conductive metal mesh formed by silver deposition on the surface are used for the purpose of blocking electromagnetic interference waves. The structure which interrupts | blocks an electromagnetic interference wave is employ | adopted by forming an electromagnetic shield with the electroconductive front glass 31 formed in this. In general, when such an electromagnetic shield structure is adopted, the conductive metal casing 30 is caused to function as an FG. 15 is a cross-sectional view of a portion A in FIG. 16 for explaining the configuration of the improved conventional PDP, and FIG. 16 is a schematic perspective view of the improved conventional PDP display device. Further, in FIG. 15, 16 is a PDP panel mounting member provided in the metallic casing 30 and functions as an FG. Reference numeral 18 denotes a bolt for attaching the chassis 111 to the PDP panel attachment member 16, and 17 denotes an insulating spacer.
[0009]
[Problems to be solved by the invention]
However, even if the PDP electromagnetic shield structure as described above is adopted, a stand for supporting a large flat display panel is generally made of a conductive metal material in consideration of design and mechanical constraints and cost. Therefore, as in the case shown in FIG. 14, resonance occurs with respect to a specific frequency that becomes an electromagnetic interference wave between the metal housing that is FG and the stand, and unnecessary radiation noise is generated. There was a problem that the level would increase.
[0010]
In view of the above problems, the present invention provides a support device that suppresses the resonance of a stand that supports a flat display panel with respect to a specific frequency, and can suppress the generation of electromagnetic interference waves as compared with a conventional structure. The issue is to provide.
[0011]
[Means for Solving the Problems]
In view of this, the support device according to the present invention is configured such that a stand column supporting the supported body is erected on the support base, and a high-frequency current loop is formed between the stand column, the support base and the supported body. In the support device, the support base or the stand column is provided with an insulating structure portion that suppresses the high-frequency current loop.
[0012]
With this configuration, resonance with respect to a specific frequency of the stand that supports the flat display panel is eliminated, and generation of electromagnetic interference waves can be suppressed.
[0013]
Specifically, the following structure can be employed for the insulating structure portion. That is, both the support base and the stand column are formed using a conductive material, the support table and the stand column are connected via an insulating spacer, and the support table and the stand column are electrically connected. The insulation structure portion can be constructed by substantially insulating.
[0014]
Further, the support base may be formed using a conductive material, and the stand column may be formed using an insulating material. In this case, the support base and the stand column are made to have an opposing portion having a length larger than the diameter of the stand column so that the whole has the same mechanical strength as a conventional stand made of a conductive metal material. Are preferably connected to each other.
[0015]
Furthermore, both the support base and the stand column are formed using a conductive material, and the support base is formed with a slit that electrically insulates the middle of the support base. Can be built. More specifically, the support base is composed of at least two base parts, and the slit is formed between the at least two base parts.
[0016]
In this case, it is preferable that at least two stand columns are provided, and the slits are formed in the support base between the adjacent stand columns.
[0017]
Further, the insulating structure portion can be constructed by connecting at least two base portions of the support base in an electrically insulated state via an insulating spacer. In this case, it is preferable that at least two base portions of the support base are connected to each other with opposing portions having a creeping distance longer than the thickness of the support base so as to have sufficient mechanical strength.
[0018]
In addition, according to the present invention, there is provided a display device comprising the support device having the above-described characteristics and a matrix-driven flat display panel having a plurality of electrodes as the supported body. Can do.
[0019]
In this case, it is more preferable to electrically insulate the frame ground of the flat display panel from the stand column.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. The display device is a color television receiver having a PDP. 1 and 2 are a cross-sectional view and a perspective view, respectively, of a portion A in FIG. 2 for explaining a housing configuration of the PDP as the display device according to the first embodiment of the present invention. In addition, only the structure part deeply related to the unnecessary radiation of the electromagnetic interference wave of the color television receiver as an embodiment is shown. FIG. 3 is a perspective view for explaining the configuration of the PDP according to the first embodiment, and FIG. 4 is a perspective view for explaining the electrode structure of the PDP according to the first embodiment. 1 to 4, the same reference numerals as those in FIGS. 12 to 16 denote the same or corresponding parts.
[0021]
In the figure, the color television receiver of the present embodiment is provided with a matrix-driven flat display panel having a plurality of electrodes 14, for example, a PDP panel 10 made of a glass substrate or the like, and the non-display surface side of the PDP panel 10 A chassis 11 which is a holding plate is arranged to hold the PDP panel 10. The driver drive circuits 13a and 13b are disposed on the rear side of the chassis 11, and signals generated from the driver drive circuits 13a and 13b are transmitted to the electrodes 14 of the PDP panel 10 by the flexible cable 15.
[0022]
In the PDP panel 10, a sustain electrode 14a and a scan electrode 14b are provided on the front glass substrate 20 on the display surface side, a write electrode 14c is formed on the opposite back glass substrate 24, and plasma discharge is generated between the write electrodes 14c. A partition wall 22 for separation is configured so as not to affect the adjacent electrode. Red 23a, blue 23b, and green 23c phosphors are separately coated on the write electrode 14c, and a discharge gas is sealed in a discharge space between the front glass substrate 20 on the display surface side and the rear glass substrate 24 facing the display glass side. The cells selected by the driver drive circuits 13a and 13b are plasma-discharged, and the red 23a, blue 23b, and green 23c phosphors emit light, thereby forming a color image.
[0023]
The chassis 11 is a conductive metal plate made of, for example, an aluminum-based material, and functions as an electrode ground that is a ground surface of the electrode 14 of the PDP panel 10 in terms of an electric circuit.
[0024]
The signal ground (SG) of the scanning / sustaining electrode driver driving circuit 13a is grounded to the chassis 11 at points B and B ', and the SG of the writing electrode driver driving circuit 13b is grounded to the chassis 11 at points C and C'. Functions as a drive circuit feedback ground which is a ground plane through which the feedback current of the driver drive circuits 13a and 13b flows.
[0025]
The conductive metal casing 30 is, for example, a conductive metal plate made of an aluminum-based material. A conductive front glass 31 is provided on the front surface of the conductive metal casing 30, and the conductive front glass 31 is conductive by, for example, silver deposition. A conductive film or conductive metal mesh is formed on the surface, and the conductive metal housing 30 and the conductive front glass 31 form an electromagnetic shield, which functions as a frame ground (FG) in terms of electrical circuit. .
[0026]
The metallic casing 30 is provided with a PDP panel mounting member 16 and functions as an FG. A chassis 111 is attached to the PDP panel attachment member 16 with bolts 18 via an insulating spacer 17.
[0027]
The stand 12 includes a conductive metal support base 12a made of, for example, an aluminum-based material and a conductive metal stand column 12b made of, for example, an aluminum-based material, and is connected to each other via an insulating spacer 17. ing. The support base 12a and the stand column 12b are connected to each other with a facing portion L having a size larger than the diameter R of the stand column 12b, thereby having the same mechanical strength as a conventional stand made entirely of conductive metal. ing.
[0028]
FIG. 5 shows a comparison of radiation noise measurement results between the conventional example shown in FIG. 15 and the 42-inch PDP television of the first embodiment shown in FIG. As a method for measuring radiation noise, a PDP television is placed on a rotating table in an anechoic chamber, and the table is rotated to measure the maximum value of the electric field strength at a distance of 3 m for each frequency.
[0029]
By connecting the support base 12a and the stand column 12b in an electrically insulated state, the high-frequency current loop between the casing 30 and the stand 12 which is FG becomes weak, and as shown in FIG. The resonance of the stand 12 is reduced, and the generation of electromagnetic interference waves due to the drive signal radiated into the air from the electric circuit formed by the housing 30 and the stand 12 can be suppressed.
[0030]
As described above, the support 12a and the stand column 12b are connected in an electrically insulated state, so that the stand 12 supporting the flat display panel does not resonate with respect to a specific frequency. Therefore, the generation of electromagnetic interference waves can be significantly suppressed as compared with the conventional structure.
[0031]
(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to FIG. The display device is a color television receiver having a PDP. FIG. 6 is a cross-sectional view for explaining a housing configuration of a PDP as a display device according to the second embodiment of the present invention. In addition, only the structure part deeply related to the unnecessary radiation of the electromagnetic interference wave of the color television receiver as an embodiment is shown. In FIG. 6, the same reference numerals as those in FIGS. 1 to 4 denote the same or corresponding parts.
[0032]
In FIG. 6, the display device of the second embodiment is different from the first embodiment shown in FIGS. 1 to 4 in that a support base 12a and a conductive metal stand column 12b are connected to an insulating spacer 17. The stand 12 is constituted by a support base 12a and an insulating stand column 12c made of ceramic, for example.
[0033]
By using the insulating stand column 12c, the high-frequency current loop between the housing 30 and the stand 12, which is an FG, is weakened, the resonance of the stand 12 is reduced, and the electricity formed by the housing 30 and the stand 12 is reduced. Generation of electromagnetic interference due to the drive signal radiated from the circuit into the air can be suppressed.
[0034]
As described above, by using the insulating stand column 12c, the stand 12 supporting the flat display panel can be prevented from resonating with respect to a specific frequency, and electromagnetic interference is greatly reduced as compared with the conventional structure. Wave generation can be suppressed.
[0035]
(Embodiment 3)
Next, a third embodiment of the present invention will be described with reference to FIG. The display device is a color television receiver having a PDP. FIG. 7 is a perspective view for explaining a stand structure of a PDP as a display device according to a third embodiment of the present invention, which is deeply affected by unnecessary radiation of electromagnetic interference waves of a color television receiver as an embodiment. Only the relevant structural parts are shown.
[0036]
The display device of the third embodiment in FIG. 7 is different from the first embodiment shown in FIGS. 1 to 4 in that the support base 12a and the conductive metal stand column 12b are connected to the insulating spacer 17. In this case, a slit 12d is formed in the support base 12a between the two stand columns 12b, and the middle of the support base 12a is electrically insulated substantially.
[0037]
By inserting the slit 12d in the support base 12a, the high-frequency current loop between the housing 30 and the stand 12, which is an FG, is weakened, the resonance of the stand 12 is reduced, and the housing 30 and the stand 12 are formed. Generation of electromagnetic interference due to a drive signal radiated from the electric circuit into the air can be suppressed.
[0038]
As described above, by inserting the slit 12d in the support base 12a, the stand 12 supporting the flat display panel can be prevented from resonating with respect to a specific frequency, and electromagnetic interference is greatly reduced as compared with the conventional structure. Wave generation can be suppressed.
[0039]
(Embodiment 4)
A fourth embodiment of the present invention will be described with reference to FIG. The display device is a color television having a PDP. FIG. 8 is a perspective view for explaining a stand structure of a PDP as a display device according to the fourth embodiment of the present invention, and a structure deeply related to unnecessary radiation of electromagnetic interference waves of the color television as the embodiment. Only the part is shown. In FIG. 8, the same reference numerals as those in FIGS. 1 to 4 indicate the same or corresponding parts.
[0040]
The display device of the fourth embodiment in FIG. 8 is different from the first embodiment shown in FIGS. 1 to 4 in that the support base 12a and the conductive metal stand column 12b are connected with the insulating spacer 17. Instead of connecting via an insulating portion, an insulating portion 12e is interposed between the support stand 12a between the two stand columns 12b.
[0041]
By interposing the insulating portion 12e on the support base 12a, the high-frequency current loop between the housing 30 and the stand 12, which is an FG, is weakened, the resonance of the stand 12 is reduced, and the housing 30 and the stand 12 are formed. The generation of electromagnetic interference due to the drive signal radiated from the electrical circuit to the air can be suppressed.
[0042]
As described above, by providing the support 12a with the insulating portion 12e, the stand 12 that supports the flat display panel can be prevented from resonating with respect to a specific frequency, which is much more electromagnetic than the conventional structure. Generation of interference waves can be suppressed.
[0043]
In the above embodiment, an example is shown in which the two base portions of the support base 12a with the insulating portion 12e interposed are connected with opposing portions having the same length as the thickness of the support base 12, but as shown in FIG. In addition, by connecting with the length N of the facing portion larger than the thickness M of the support base 12a, the above-described effect can be obtained while maintaining the mechanical strength.
[0044]
Further, by adopting a wedge-shaped connection structure as shown in FIG. 10, the tensile strength in the left-right direction is increased and the mechanical strength is maintained, and the above-described effect can be obtained.
[0045]
In the above-described embodiment, the case where the support base 12a is composed of two base parts has been described as an example. However, the present invention is not limited to this. For example, as shown in FIG. It can also be applied to a support device consisting of three parts or three or more base parts, and the above-mentioned effect can be obtained while maintaining mechanical strength.
[0046]
In the above description of the present invention, the PDP has been described. However, the present invention is not limited to this, and can be applied to all display devices having a matrix-driven flat display panel having a plurality of electrodes such as liquid crystal. The same effect is produced.
[0047]
In the above embodiments, the case of a casing made of an aluminum-based material has been described as an example. However, the present invention can be similarly applied to a display device having a casing made of another conductive material such as a copper-based material. In the above embodiment, the case where the metal casing is FG has been described as an example. However, the present invention can also be applied to a display device in which another conductive member such as a chassis functions as FG. In the above embodiment, a 42-inch color television receiver is described as an example. However, the present invention can be applied to display devices of other sizes.
[0048]
【The invention's effect】
As described above, by connecting the support base and the stand column in an electrically insulated state, it is possible to suppress the stand supporting the flat display panel from resonating with respect to a specific frequency. Compared with the structure, the generation of electromagnetic interference can be significantly suppressed.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view for explaining a housing configuration of a PDP as a display device according to a first embodiment.
FIG. 2 is a perspective view for explaining a housing configuration of the PDP according to the first embodiment.
FIG. 3 is a perspective view for explaining the configuration of the PDP according to the first embodiment.
FIG. 4 is a perspective view for explaining an electrode structure of the PDP according to the first embodiment.
FIG. 5 is a graph showing the electric field strength at the noise level in the vertical direction, which is the electromagnetic interference reduction effect of the first embodiment.
FIG. 6 is a cross-sectional view for explaining a housing configuration of a PDP according to a second embodiment.
FIG. 7 is a perspective view for explaining a stand configuration of a PDP according to a third embodiment.
FIGS. 8A and 8B are a perspective view and a cross-sectional view for explaining a stand configuration of a PDP according to a fourth embodiment. FIGS.
FIG. 9 is a cross-sectional view for explaining a stand configuration of a PDP according to a fifth embodiment.
FIG. 10 is a cross-sectional view for explaining a stand configuration of a PDP according to a sixth embodiment.
FIG. 11 is a cross-sectional view for explaining a stand configuration of a PDP according to a seventh embodiment.
FIG. 12 is a perspective view for explaining the configuration of a conventional PDP.
FIG. 13 is a perspective view for explaining an electrode structure of a conventional PDP.
FIG. 14 is a perspective view for explaining stand resonance of a conventional PDP.
FIG. 15 is a cross-sectional view for explaining a housing configuration of another conventional PDP.
FIG. 16 is a perspective view for explaining a housing configuration of another conventional PDP.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 PDP panel 11 Chassis 12 Stand 12a Support stand 12b Stand support | pillar 12c Insulation stand support | pillar 12d Support stand slit 12e Support stand insulating part 13a Driver drive circuit (scanning, sustain electrode)
13b Driver drive circuit (write electrode)
14 electrode 14a sustain electrode 14b scan electrode 14c write electrode 15 flexible cable 16 PDP panel mounting member 17 insulating spacer 18 bolt 20 front glass substrate 21 dielectric layer 22 partition wall 23a red phosphor 23b blue phosphor 23c green phosphor 24 back Glass substrate 30 Conductive metal casing 31 Conductive front glass 40 Current vector 41 High-frequency current loop

Claims (7)

Is constructed by erecting the stand supports for flat display panel of matrix drive type having a plurality of electrodes on the support base, said stand support, support base and the display device a high-frequency current loop is formed between the display panel In
At least two stand columns are provided,
A display device, wherein an insulating structure that suppresses the high-frequency current loop is provided on the support base between the adjacent stand columns. The display device according to claim 1, wherein both the support base and the stand column are formed using a conductive material. The display device according to claim 1, wherein the insulating structure is a slit that electrically insulates the middle of the support base. The display device according to claim 3, wherein the support base includes at least two base parts, and the slit is formed between the at least two base parts. The display device according to claim 1, wherein the insulating structure is an insulating spacer that electrically insulates the middle of the support base. 6. The display according to claim 5, wherein the support base is composed of at least two base parts, and the at least two base parts are connected in an electrically insulated state via an insulating spacer. apparatus. Wherein the frame ground of said display panel and said stand support are electrically connected, the display device according to any one of claims 1 to 6.

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