JP2004031240A - Cathode-ray tube device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cathode-ray tube device that can accommodate various scanning line modes without lowering luminance and degrading image quality. <P>SOLUTION: A shadow mask 6 of the cathode-ray tube device comprises a substantially rectangular shadow mask body 14 with many openings 12 in a principal plane part 11 opposed to a phosphor screen. The shadow mask body 14 has, in a longer axis direction H, a plurality of opening lines 20 of pluralities of openings 12 arrayed in a shorter axis direction V. When the sum of the diameter of the openings 12 in the shorter axis direction and the length of bridges 19 between the openings in the shorter axis direction is set as one pitch, adjacent opening lines 20 are formed at different pitches. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cathode ray tube device, and more particularly to a structure of a shadow mask applied to a color cathode ray tube device.
[0002]
[Prior art]
2. Description of the Related Art Generally, a color cathode ray tube device includes a shadow mask disposed to face a phosphor screen formed on an inner surface of a panel of a vacuum envelope. This shadow mask has a number of electron beam passage holes 60 as shown in FIG. That is, the electron beam passage holes 60 having a substantially rectangular shape form an opening row 70 which is arranged along the short axis direction V of the shadow mask 59 via the bridge 69 having a constant width. The plurality of aperture rows 70 are arranged along the long axis direction H.
[0003]
Each opening row 70 is arranged such that the sum of the diameter of the electron beam passage hole 60 in the short axis direction and the length of the bridge 69 in the short axis direction V is one pitch (Pv). The adjacent opening rows 70 are formed such that the adjacent electron beam passage holes 60 are shifted by (Pv / 2) in the minor axis direction V.
[0004]
In such a color cathode ray tube device, Pv is substantially constant in the main surface portion of the shadow mask, and the bridge 69 is located at the same position in the short axis direction V every other row of the opening rows 70. In other words, the bridge 69 always exists on any scanning line. For this reason, a part of the electron beam deflected in the horizontal direction is blocked by the bridge 69 of the shadow mask existing on the scanning line and cannot reach the phosphor screen.
[0005]
Therefore, the brightness of the screen is reduced, and it is necessary to increase the power consumption to compensate for the reduced brightness. In addition, the occurrence of moire or the like may cause deterioration in image quality.
[0006]
[Problems to be solved by the invention]
By the way, a recent color cathode ray tube device is used also as a terminal device of a computer or a digital television corresponding to the multimedia. For this reason, the scanning line modes are diversified, and the number of television sets having a switching mechanism corresponding to these scanning line modes is increasing.
[0007]
In a color cathode ray tube apparatus used in a television set having such a scanning line switching mechanism, moire is generated for various scanning line modes by changing Pv including the width of the bridge and the minor axis diameter of the opening in the shadow mask. It must be set so as not to occur, and it is difficult to determine this value as the number of scan line modes increases.
[0008]
As a method of reducing this moiré, it is necessary to determine the bridge width and the opening diameter so that moiré does not occur depending on the number of scanning lines, but a method of reducing the pitch Pv is generally used. However, in the method of simply reducing the pitch Pv, moire may occur depending on the scanning line mode, and the luminance of the screen may be reduced.
[0009]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and has as its object to provide a cathode ray tube device capable of supporting various scanning line modes without causing a decrease in luminance and a deterioration in image quality. It is in.
[0010]
[Means for Solving the Problems]
A cathode ray tube device according to an embodiment of the present invention includes:
A vacuum envelope with a substantially rectangular panel having a long axis and a short axis orthogonal to each other;
A phosphor screen arranged on the inner surface of the panel,
An electron gun assembly disposed in a neck of the vacuum envelope and emitting an electron beam toward the phosphor screen;
A shadow mask disposed opposite to the phosphor screen,
In a cathode ray tube device provided with
The shadow mask includes a substantially rectangular shadow mask body having a number of openings on a surface facing the phosphor screen,
The shadow mask body has a plurality of openings in the long axis direction, the openings being formed by a plurality of openings arranged along the short axis direction,
When the sum of the short-axis diameter of the opening and the short-axis length of the bridge provided between the openings is one pitch, the opening rows adjacent to each other are formed at different pitches.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a cathode ray tube device according to an embodiment of the present invention will be described with reference to the drawings.
[0012]
As shown in FIGS. 1 to 3, the cathode ray tube device has a substantially rectangular panel 3 having a major axis H and a minor axis V orthogonal to each other and a funnel 4 connected to the panel 3. It has a vessel. The panel 3 includes an effective surface 1 having a substantially perfect outer surface with a flat curvature, and a skirt portion 2 extending in the tube axis direction Z from the periphery of the effective surface 1.
[0013]
The phosphor screen 5 is arranged on the inner surface of the panel 3. The phosphor screen 5 is configured such that three-color phosphor layers 62R, 62G, and 62B that respectively emit red, green, and blue light are embedded in gaps between the stripe-shaped light absorbing layers 61, for example. The shadow mask 6 is arranged at a predetermined distance from the phosphor screen 5.
[0014]
The electron gun structure 9 is disposed in the neck 7 corresponding to the small diameter portion of the funnel 4. The electron gun assembly 9 emits three electron beams 8R, 8G, and 8B arranged in a line along the long axis direction H. The deflection yoke 10 is arranged along the outer surface of the funnel 4. The deflection yoke 10 generates a non-uniform deflection magnetic field for deflecting the three electron beams 8R, 8G, 8B emitted from the electron gun assembly 9 in the major axis direction H and the minor axis direction V. This non-uniform deflection magnetic field is formed by a pincushion type horizontal deflection magnetic field and a barrel type vertical deflection magnetic field.
[0015]
The three electron beams 8R, 8G, and 8B emitted from the electron gun assembly 9 are deflected by the deflecting magnetic field generated from the deflecting yoke 10 and move the phosphor screen 5 through the shadow mask 6 in the long axis direction and the short axis direction. Scan. Thereby, a color image is displayed.
[0016]
Further, the shadow mask 6 includes a substantially rectangular shadow mask main body 14 constituted by the main surface portion 11 and the skirt portion 13. The main surface portion 11 is a substantially rectangular curved surface facing the phosphor screen 5 and has many openings 12. The skirt portion 13 extends from the peripheral portion of the main surface portion 11 in the tube axis direction Z, and is formed in a rectangular frame shape.
[0017]
Further, the shadow mask 6 includes a substantially rectangular frame portion 15 for mounting the shadow mask body 14. This frame portion 15 is arranged along the outer periphery of the skirt portion 13 of the shadow mask body 14. Further, the frame portion 15 has a substantially L-shaped cross section, and extends substantially parallel to the skirt portion 13 of the shadow mask body 14, and a frame side wall portion 16A extending substantially from the end of the frame side wall portion 16A. And a frame bottom surface portion 16B connected at a right angle.
[0018]
The skirt portion 13 of the shadow mask main body 14 is welded to the frame side wall portion 16A. The substantially wedge-shaped elastic support 17 is attached to a corner of the frame side wall 16A. The shadow mask main body 14 is detachably supported inside the panel 3 by engaging the elastic support 17 with a stud pin 18 provided inside the skirt portion 2 of the panel 3.
[0019]
Meanwhile, the plurality of openings 12 formed in the main surface portion 11 of the shadow mask main body 14 are arranged along the short axis direction V, as shown in FIGS. I have. Each opening row 20 includes a bridge 19 provided between the openings 12. The plurality of opening rows 20 are arranged along the long axis direction H.
[0020]
In this embodiment, when the sum of the short-axis direction diameter P12 of the opening 12 and the short-axis direction length P19 of the bridge 19 is one pitch Pv, the opening rows adjacent to each other have different pitches Pv. Is formed. That is, in the example shown in FIG. 5, the short-axis direction length P19 of the bridge 19 is a fixed width, whereas the openings 12 constituting the adjacent opening rows 20 have different short-axis direction diameters. P12 is provided.
[0021]
Further, the opening row 20 at the center of the main surface portion 11 of the shadow mask body 14 along the major axis direction H is set to N = 1, and the opening row is set to N = 2 from the center to the peripheral portion along the major axis direction H. .., 3, 4,..., The pitch is different between the even-numbered row and the odd-numbered row. At this time, it is desirable that one of the pitches Pv of the even-numbered rows and the odd-numbered rows is an integral multiple of the other.
[0022]
In the example shown in FIG. 5, the pitch Pv of the even-numbered rows is set to be about twice that of the odd-numbered rows. That is, in each of the opening rows, the short-axis direction length P19 of the bridge 19 is about 0.12 mm, the short-axis direction diameter P12 in the odd-numbered row of openings 12 is about 0.60 mm, and the odd-numbered row The diameter P12 in the minor axis direction of the portion 12 is about 1.32 mm, the pitch Pv of the odd rows is 0.72 mm, and the pitch Pv of the even rows is 1.44 mm.
[0023]
By arranging such aperture rows 20, bridges 19 exist every other row on some scanning lines, but no bridges 19 exist on aperture rows 20 on other scanning lines. In the example shown in FIG. 5, the portions that have been bridges in the past become openings 12 every other row. For example, every other scan line becomes a scan line without a bridge 19.
[0024]
Thus, when the three electron beams 8 (R, G, B) are deflected along the major axis direction H, a part of the beams 8 reach the phosphor screen 5 without being interrupted by the bridge 19. Therefore, it is possible to prevent a decrease in screen brightness. For this reason, it is not necessary to increase the power consumption to compensate for the luminance decrease. Further, by configuring the adjacent opening rows at the pitch as described above, it becomes possible to support various scanning line modes, and even when screen display is performed in any of the scanning line modes, generation of moiré can be prevented. And deterioration of image quality can be suppressed.
[0025]
Next, the measurement results of the moire contrast and the screen luminance in the present embodiment and the conventional example will be described. Here, a color cathode ray tube device having an effective screen diagonal size of 80 cm and an aspect ratio of 4: 3 was used.
[0026]
The pitch Pv in the conventional shadow mask was 0.72 mm. In the shadow mask of this embodiment, the pitch Pv was set to 0.72 mm for odd-numbered aperture rows and 1.44 mm for even-numbered aperture rows.
[0027]
As shown in FIG. 6, the pitch of the moire generated on the screen was almost equal in both the case of the NTSC system and the case of the PAL system as the scanning line mode. However, in any of the scanning line modes, it was confirmed that the contrast of the bright and dark portions of the moire was smaller in the present embodiment. That is, in the present embodiment, the pitch was optimized so as to be compatible with various scanning line modes, and it was possible to make the moiré inconspicuous in each scanning line mode so as not to be discriminated, thereby suppressing the deterioration of image quality. .
[0028]
Further, as shown in FIG. 7, when the luminance at the center of the screen is adjusted to the same level, the anode current is required to be 1900 μA in the conventional example, whereas it is 1750 μA in the present embodiment, and the power consumption is reduced by 8%. We were able to. That is, in the conventional example, since a bridge exists on any of the scanning lines, a part of the electron beam cannot reach the phosphor screen, but in the present embodiment, the bridge does not exist on some of the scanning lines. Therefore, a part of the electron beam is not blocked by the bridge, and the luminance can be improved. This makes it possible to prevent an increase in power consumption.
[0029]
In the above-described embodiment, an example was described in which the pitch Pv of the even-numbered rows was set to twice that of the odd-numbered rows. However, the present invention is not limited to this example. Needless to say, the effect is obtained.
[0030]
For example, if the strength of the shadow mask itself can be sufficiently ensured, when the pitch of the first row is Pv, the pitch of the second row is (2 × Pv), and the pitch of the third row is (3 × Pv). , The pitch of the fourth row may be (4 × Pv),. Further, a plurality of rows (for example, three rows) may be defined as one block, and aperture rows having different pitches may be arranged in one block (for example, the pitch of the (1n) row is Pv, and the pitch of the (2n) row is (2 × Pv), (3n) The pitch of the row may be (3 × Pv).
[0031]
Further, in the above-described embodiment, in order to form the opening rows adjacent to each other at different pitches, the length of the bridge in the short axis direction is made constant, and the diameter of the opening in the short axis direction is made different depending on the opening rows. The length of the bridge width in the minor axis direction may be different depending on the opening row, or both may be different depending on the opening row.
[0032]
As described above, according to the cathode ray tube device according to the present embodiment, the shadow mask has a plurality of opening rows constituted by a plurality of openings arranged in the minor axis direction on the main surface thereof. ing. The pitch of each opening row is defined by the sum of the short-axis diameter of one opening and the short-axis length of one bridge provided between the openings. The plurality of opening rows are arranged at substantially constant intervals along the long axis direction.
[0033]
And the opening rows adjacent to each other are formed at different pitches. That is, the opening rows adjacent to each other are constituted by openings having different short-axis diameters. Further, when the opening row at the center along the major axis direction of the shadow mask main surface portion is N = 1, and the opening rows are N = 2, 3, 4,... From the center to the periphery along the major axis direction. , The pitch is set to be different between the even-numbered row and the odd-numbered row. For example, one of the pitches of the even-numbered row and the odd-numbered row is set to an integral multiple of the other.
[0034]
This makes it possible to cope with various scanning line modes, and it is possible to make the moire inconspicuous so that it cannot be discriminated. Further, the brightness of the screen can be improved, and power consumption can be reduced. For this reason, it is possible to display a high-luminance and high-quality screen even when applied to a computer terminal device compatible with multimedia, a digital television, or the like.
[0035]
It should be noted that the present invention is not limited to each embodiment, and various modifications and changes can be made at the stage of implementation without departing from the scope of the invention. In addition, the embodiments may be implemented in appropriate combinations as much as possible, and in that case, the effect of the combination is obtained.
[0036]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a cathode ray tube device capable of supporting various scanning line modes without causing a decrease in luminance and a deterioration in image quality.
[Brief description of the drawings]
FIG. 1 is a partial horizontal sectional view schematically showing a structure of a color cathode ray tube device according to an embodiment of the present invention.
FIG. 2 is a diagram for explaining how an electron beam in the color cathode ray tube device shown in FIG. 1 reaches a phosphor screen.
FIGS. 3A and 3B are diagrams showing the structure of the shadow mask shown in FIG. 1 in more detail; FIG. 3A is a front view of the shadow mask; FIG. 3B shows a cross-sectional view of the shadow mask.
FIG. 4 is a diagram showing an arrangement state of an opening row formed in the shadow mask shown in FIG. 1;
FIG. 5 is an enlarged view of an opening row at a central portion of the main surface of the shadow mask shown in FIG. 4;
FIG. 6 is a diagram showing a measurement result of comparing the moire contrast between the present embodiment and a conventional example.
FIG. 7 is a diagram showing a measurement result of comparing screen luminance between the present embodiment and a conventional example.
FIG. 8 is an enlarged view of a row of openings in a central portion of a main surface of a shadow mask of a conventional example.
[Explanation of symbols]
3 Panel 4 Funnel 5 Phosphor Screen 6 Shadow Mask 9 Electron Gun Assembly 11 Main Surface 12 Opening 14 Shadow Mask Body 15 Frame 19 Bridge Pv Pitch

Claims (4)

A vacuum envelope with a substantially rectangular panel having a long axis and a short axis orthogonal to each other;
A phosphor screen arranged on the inner surface of the panel,
An electron gun assembly disposed in a neck of the vacuum envelope and emitting an electron beam toward the phosphor screen;
A shadow mask disposed opposite to the phosphor screen,
In a cathode ray tube device provided with
The shadow mask includes a substantially rectangular shadow mask body having a number of openings on a surface facing the phosphor screen,
The shadow mask body has a plurality of openings in the long axis direction, the openings being formed by a plurality of openings arranged along the short axis direction,
A cathode ray tube characterized in that, when the sum of the short-axis diameter of the opening and the short-axis length of the bridge provided between the openings is one pitch, the opening rows adjacent to each other are formed at different pitches. apparatus. 2. The cathode ray tube device according to claim 1, wherein the opening rows adjacent to each other are constituted by openings having different short-axis diameters. 3. When the row of openings at the center of the shadow mask body along the long axis direction is N = 1, and the rows of openings are N = 2, 3, 4,... The cathode ray tube device according to claim 1, wherein the pitch is different between the row and the odd row. 4. The cathode ray tube device according to claim 3, wherein one of the pitches of the even-numbered rows and the odd-numbered rows is an integral multiple of the other.

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