JP2007149456A - Color cathode-ray tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure a spacing between a flare portion of a mask frame and a panel and an insertion property of a skirt of a shadow mask into the mask frame without losing strength of the mask frame. <P>SOLUTION: A flare portion 9b bent to a side approaching to a side wall 1b of a panel 1 are formed on a phosphor screen 7 side end of a side wall 9a of a mask frame 9. When protruding amounts of the flare 9b from the outer surface of the side wall 9a are WL1 in the center of a long side of the frame mask, WS1 in the center of the short side of the frame mask, WD in the center of a corner of the frame mask, WLm in the neighborhood of the boundary between the long side and the corner of the frame mask, and WSm in the neighborhood of the boundary between the short side and the corner of the frame mask; formulas WL1≥WD>WLm, WS1≥WD>WSm are satisfied. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a color cathode ray tube provided with a shadow mask.

  The color cathode ray tube has a shadow mask facing a phosphor screen formed on the inner surface of the panel. The shadow mask includes a main surface having a curved surface protruding to the phosphor screen side, and a skirt portion that is continuously provided around the main surface and is bent to the opposite side of the phosphor screen. The shadow mask is held by a mask frame having a substantially rectangular frame shape. And this mask frame is fixed to the inner surface of the side wall of a panel via the spring each fixed to the four corner parts.

  The mask frame includes a side wall portion that contacts the outer surface of the skirt portion of the shadow mask over substantially the entire circumference. The shadow mask skirt is fitted between the opposing side walls of the mask frame, and the side wall of the mask frame and the skirt of the shadow mask are welded.

  In such a color cathode ray tube, a flare portion is formed on the side wall portion of the mask frame so that the side end (phosphor screen side end) into which the shadow mask is fitted is deformed into a flare shape so that the inner dimension is enlarged. Sometimes.

  When the shadow mask and the mask frame are integrated, the flare portion guides the skirt portion of the shadow mask so that it can be easily fitted between the opposing side wall portions of the mask frame, so that the shadow mask is attached to the mask frame. Improve assembly work efficiency. Further, the flare portion contributes to an improvement in the strength and weight reduction of the mask frame (see, for example, Patent Document 1).

  FIG. 7 is a plan view of a panel to which a mask frame for holding a shadow mask is attached as viewed from the mask frame side. FIG. 8 is an enlarged plan view showing the vicinity of the corner portion of FIG. As shown in FIGS. 7 and 8, the flare portion 9b is formed over the entire circumference of the mask frame 9, and the amount of protrusion from the outer surface of the side wall portion 9a is generally uniform over the entire circumference of the mask frame 9. Is. 7 and 8, 1b is a side wall of the panel 1, 24 is a stud pin implanted in the side wall 1a of the panel 1, 11 is a spring fixed to a corner portion of the mask frame 9, 2 is a shadow mask, 8 is This is a shadow mask structure in which the shadow mask 2 is held on the mask frame 9.

However, since it is difficult to form a flare portion by press molding at and / or near the four corner portions of the mask frame, the cut portion is cut between the flare portion of the corner portion and the flare portions of the long side and the short side. There are cases where a notch is provided to make the flare portion 9b discontinuous (see, for example, Patent Document 2), or the flare portion 9b is not formed in the corner portion as shown in FIG.
Japanese Patent Laid-Open No. 11-54063 JP 2004-172060 A

  However, as shown in FIGS. 7 and 8, when the flare portion 9b having a uniform protrusion amount is formed over the entire circumference of the mask frame 9, the distance between the flare portion 9b and the inner surface of the side wall 1b of the panel 1 is as follows. Narrow. As a result, when the shadow mask structure 8 is incorporated into the panel 1, the workability is deteriorated, and the flare portion 9 b collides with the inner wall of the panel 1 to damage the panel 1.

  Further, when a notch is provided between the flare portion of the corner portion and the flare portions of the long side and the short side to make the flare portion 9b discontinuous, stress concentrates around the notch and the resistance of the mask frame is increased. The torsional strength will decrease.

  Furthermore, as shown in FIG. 9, when the flare portion 9b is not formed in the corner portion, the workability of fitting the skirt portion of the shadow mask 2 to the mask frame 9 in the corner portion (hereinafter referred to as “insertability”) is achieved. This lowers the efficiency of assembling the shadow mask 2 to the mask frame 9. In addition, the strength of the mask frame decreases at the corner portion.

  The present invention solves the above-described conventional problems, secures the space between the flare portion of the mask frame and the panel, and does not reduce the strength of the mask frame, so that the skirt portion of the shadow mask can be fitted into the mask frame. An object of the present invention is to provide a color cathode ray tube excellent in

  A color cathode ray tube according to the present invention includes a panel having a phosphor screen formed on the inner surface, a shadow mask arranged to face the phosphor screen, a mask frame having a substantially rectangular frame shape holding the shadow mask, A spring that is fixed to each of the four corners of the mask frame and that fixes the mask frame to the inner surface of the side wall of the panel;

  The shadow mask includes a main surface having a curved surface protruding toward the phosphor screen, and a skirt portion provided continuously around the main surface and bent to the opposite side of the phosphor screen.

  The mask frame includes a side wall portion that comes into contact with the skirt portion of the shadow mask, and a flare portion that is bent at the phosphor screen side end of the side wall portion so as to be closer to the side wall of the panel. Is provided.

  The flare portion is formed continuously over the entire circumference of the mask frame so as to surround the shadow mask.

The amount of protrusion of the flare from the outer surface of the side wall is WL1 at the center of the long side of the mask frame, WS1 at the center of the short side of the mask frame, WD at the center of the corner of the mask frame, When WLm is near the boundary between the long side and the corner portion, and WSm is near the boundary between the short side and the corner portion of the mask frame,
WL1 ≧ WD> WLm
WS1 ≧ WD> WSm
Satisfied.

  According to the present invention, there is provided a color cathode ray tube in which the space between the flare portion of the mask frame and the panel is ensured and the skirt portion of the shadow mask is well fitted into the mask frame without reducing the strength of the mask frame. Can be provided.

  FIG. 1 is a cross-sectional view of a color cathode ray tube according to an embodiment of the present invention. FIG. 2 is a perspective view of the shadow mask structure 8 in which the shadow mask 2 is held on the mask frame 9. FIG. 3 is a plan view of the panel 1 to which the shadow mask structure 8 is attached as viewed from the mask frame 9 side. 4 is a cross-sectional view taken along line IV-IV in FIG. As shown in the figure, an axis parallel to the long side of the mask frame 9 is taken as an X axis, and an axis parallel to the short side is taken as a Y axis. The X axis and the Y axis are orthogonal to each other on the tube axis (that is, the Z axis) of the color cathode ray tube.

  As shown in FIG. 1, the color cathode ray tube includes an envelope in which a substantially rectangular panel 1 and a funnel 3 are joined, and the internal space is kept in a vacuum state. The panel 1 has a face part 1a and a side wall 1b formed on the periphery of the face part 1a. The outer surface of the face portion 1a is substantially rectangular. The funnel 3 is connected to the side wall 1b of the panel 1 on the large-diameter portion side.

  A phosphor screen 7 is formed on the inner surface of the face portion 1a. The phosphor screen 7 has a black light absorbing layer and three color phosphor layers. The black light absorption layer has a plurality of stripe shapes extending in a direction parallel to the Y axis, and the plurality of stripes of the black light absorption layer are arranged in parallel with a predetermined gap in the X axis direction. Each color phosphor layer constituting the three-color phosphor layer has a stripe shape extending in a direction parallel to the Y axis, and is sequentially arranged one by one in a gap between a plurality of stripes of the black light absorbing layer. .

  An electron gun 5 is provided in the internal space of the cylindrical neck 6 in the funnel 3. The electron gun 5 normally emits three electron beams in which a center beam and a pair of side beams on both sides thereof are arranged in a line in the horizontal axis direction (X-axis direction) toward the phosphor screen 7 in the Z-axis direction. An in-line type electron gun is used.

  A deflection yoke (deflector) 4 is mounted on the outer peripheral surface of the funnel 3. The deflection yoke 4 has a horizontal deflection coil and a vertical deflection coil for forming a deflection magnetic field, and deflects the three electron beams emitted from the electron gun 5 by a magnetic action.

  A shadow mask 2 is provided in the inner space of the envelope so as to face the phosphor screen 7 at a predetermined interval. The shadow mask 2 is formed with a plurality of through holes (electron beam passage holes) through which three electron beams for image display pass in a predetermined arrangement. In general, shadow masks are roughly classified into a dome-shaped press-forming mask formed by pressing and a planar tension mask stretched and fixed to a frame. In the present invention, the simple term “shadow mask” refers to a press forming mask.

  The three electron beams emitted from the electron gun 5 are deflected in the X-axis direction and the Y-axis direction by the deflection magnetic field generated by the deflection yoke 4, pass through the aperture of the shadow mask 2, and then pass through the phosphor screen 7 on the X-axis. Scan in the direction and the Y-axis direction. Thereby, a color image is displayed on the phosphor screen 7.

  As shown in FIGS. 2 and 3, the shadow mask 2 is held by a mask frame 9 having a substantially rectangular frame shape. The mask frame 9 has four springs (elastic supports) 11 fixed to the four corner portions of the outer wall surface of the mask frame 9 and four corner portions of the panel 1 which are implanted so as to protrude from the inner surface of the side wall 1b. By engaging with the two stud pins 24, the panel 1 is detachably locked.

  The shadow mask 2 has a main surface 2a having a curved surface protruding toward the phosphor screen 7 and a skirt portion 2d (see FIGS. 1 and 4) continuously provided around the main surface 2a. The skirt portion 2d is bent to the opposite side of the phosphor screen 7 with respect to the main surface 2a. The main surface 2a has a perforated portion 2b formed with a large number of electron beam passage holes through which three electron beams pass, and a non-perforated portion 2c formed around the perforated portion 2b.

  The mask frame 9 has a side wall portion 9a substantially parallel to the Z axis. A flare portion 9b that is bent and deformed in a flare shape is formed at the end of the side wall portion 9a on the phosphor screen side so that the tip of the side wall portion 9a approaches the side wall 1b of the panel 1 (that is, away from the Z axis). .

  In a state before the shadow mask 2 is integrated with the mask frame 9, the skirt portion 2d of the shadow mask 2 increases so that the interval between the opposing skirt portions 2d becomes closer to the edge on the electron gun side. Inclined with respect to the Z axis. As a result, in the state before the shadow mask 2 is integrated with the mask frame 9, the outer dimension of the opposing skirt portion 2d of the shadow mask 2 is the inner dimension of the opposing sidewall portion 9a of the mask frame 9 corresponding thereto. It is larger and smaller than the inner dimension of the tip of the opposed flare portion 9b corresponding thereto.

  The work of integrating the shadow mask 2 and the mask frame 9 by fitting the skirt portion 2d of the shadow mask 2 between the opposing side wall portions 9a of the mask frame 9 is performed as follows. The shadow mask 2 is inserted into the mask frame 9 by inserting the skirt portion 2d between the opposing flare portions 9b. The skirt portion 2d is elastically deformed in a direction approaching the Z axis while sliding on the flare portion 9b. After the shadow mask 2 is fitted to the mask frame 9 to a predetermined depth, the side wall portion 9a of the mask frame 9 and the skirt portion 2d of the shadow mask 2 are welded.

  Since the flare portion 9b is formed on the side wall portion 9a of the mask frame 9, the skirt portion 2d of the shadow mask 2 can be easily slid between the opposing side wall portions 9a of the mask frame 9. The insertion property of the skirt part 2d of the shadow mask 2 with respect to is improved. Further, the flare portion 9b contributes to improvement in strength and weight reduction of the mask frame 9.

  The skirt portion 2d of the shadow mask 2 may have a cut in at least one of the long side, the short side, and the corner portion, but is formed over substantially the entire circumference of the shadow mask 2. Therefore, the flare portion 9 b is continuously formed over the entire circumference of the mask frame 9 so as to surround the shadow mask 2 in a state where the shadow mask 2 is integrated with the mask frame 9. Thereby, the insertion property of the skirt part 2d of the shadow mask 2 with respect to the mask frame 9 is ensured.

  As shown in FIG. 4, let W be the amount of protrusion from the outer surface of the side wall portion 9a of the flare portion 9b (the surface opposite to the Z axis, ie, the surface facing the side wall 1b of the panel 1).

  As shown in FIGS. 7 and 8, when the flare portion 9b is formed over the entire circumference of the mask frame 9 and the protrusion amount W is uniform over the entire circumference of the mask frame 9, the flare portion 9b The location where the space | interval C of the front-end | tip and the side wall 1b of the panel 1 becomes narrow generate | occur | produces. Therefore, when the shadow mask structure 8 is incorporated into the panel 1, problems such as poor workability and the flare portion 9b colliding with the inner wall of the panel 1 cause damage to the panel 1.

  In order to avoid this problem, as shown in FIG. 9, when the flare portion 9b is not formed in the corner portion and the vicinity thereof where the interval C is likely to be narrow, the shadow mask 2 with respect to the mask frame 9 is formed at the corner portion. There arises a problem that the fitting property of the skirt portion 2d is lowered and the strength of the frame 9 is lowered.

  The present invention has the following configuration in order to solve the above problems.

  First, the flare portion 9 b is continuously formed over the entire circumference of the mask frame 9 in order to ensure the fit of the skirt portion 2 d of the shadow mask 2 with respect to the mask frame 9 and the strength of the mask frame 9.

Secondly, in order to ensure a sufficient distance C in the vicinity of the corner portion where the distance C between the flare portion 9b and the side wall 1b of the panel 1 tends to be narrow, the long side and the short side of the mask frame 9 and the corner portion The protrusion amount W of the flare portion 9b is reduced in the vicinity of the boundary. Specifically, as shown in FIG. 5, the amount of protrusion from the outer surface of the side wall 9a of the flare 9b is WL1 at the center of the long side of the mask frame 9, WS1 at the center of the short side of the mask frame 9, and the mask frame 9 WD at the center of the corner, WLm near the boundary between the long side of the mask frame 9 and the corner, and WSm near the boundary between the short side of the mask frame 9 and the corner,
WL1 ≧ WD> WLm
WS1 ≧ WD> WSm
Satisfied. Here, the protrusion amounts WL1 and WS1 are the maximum value of the protrusion amount of the flare portion 9b at the long side and the short side, and the protrusion amounts WLm and WSm are the protrusion amounts WLm and WSm of the flare portion 9b near the boundary between the long side and the short side and the corner portion. The minimum amount of protrusion.

  In order to realize the flare portion 9b, for example, the edge shape of the flare portion 9b viewed from the direction parallel to the Z-axis can be set as follows. The edge shape of the long-side flare portion 9b is an arc shape with a radius RLa whose center is on the Y axis in a region excluding the vicinity of the corner portion, and an arc shape with a radius RLb in the vicinity of the corner portion. Further, the edge shape of the short-side flare portion 9b is an arc shape with a radius RSa whose center is on the X axis in a region excluding the vicinity of the corner portion, and an arc shape with a radius RSb in the vicinity of the corner portion. Alternatively, instead of the arc shape of the radius RLa and the arc shape of the radius RSa, a linear shape in which the protruding amount of the flare portion 9b gradually decreases as it approaches the corner portion may be used. In any case, the flare portions 9b of the long side and the short side gradually and gradually decrease the protrusion amount of the flare portion 9b as the corner portion is approached from the center of each side. It is preferable that it is connected to the portion 9b.

  By doing in this way, the protrusion amount of the flare part 9b becomes the minimum in the corner part vicinity where the space | interval C of the flare part 9b and the side wall 1b of the panel 1 becomes narrow easily. As a result, the flare portion 9b can be continuously formed over the entire circumference of the mask frame 9 while avoiding the flare portion 9b from colliding with the inner wall of the panel 1.

  Further, at the corner portion where the distance C between the flare portion 9b and the side wall 1b of the panel 1 can be secured relatively large, the protruding amount of the flare portion 9b can be increased. Therefore, since the corner portion where stress is likely to concentrate is reinforced, the rigidity of the mask frame 9 is improved.

  Further, since the flare portion 9b is continuously formed over the entire circumference of the mask frame 9, and the amount of protrusion of the flare portion 9b changes smoothly and continuously, the occurrence of local stress concentration is prevented. The strength of the mask frame 9 can be prevented from being lowered.

  Examples are shown below. FIG. 6 is an enlarged plan view of the corner portion in a state where the shadow mask structure 8 is held via the spring 11 and the stud pin 24 arranged in the corner portion on the color cathode ray tube panel 1 having a diagonal effective dimension of the screen of 80 cm. It is.

  In the first embodiment, as shown in FIG. 6, the edge shape of the flare portion 9b on the long side of the mask frame 9 when viewed from the direction parallel to the Z-axis is a corner from the center of the long side except the vicinity of the corner portion. In the region of about 90% of the distance to the boundary with the portion, the center is an arc shape with a radius of about 8400 mm on the Y axis, and in the vicinity of the corner portion, the arc shape has a radius of about 60 mm. Similarly, the edge shape of the short-side flare portion 9b is also a curve along two large and small arcs. In the first embodiment, the amount of protrusion of the flare portion 9b from the outer surface of the side wall portion 9a is WL1 = 10 mm at the center of the long side of the mask frame 9, WS1 = 10 mm at the center of the short side of the mask frame 9, and the corner portion of the mask frame 9 WD = 6 mm in the center, WLm = 3 mm in the vicinity of the boundary between the long side and the corner portion of the mask frame 9, and WSm = 3 mm in the vicinity of the boundary between the short side and the corner portion of the mask frame 9. The flare portion 9b was continuously formed over the entire circumference of the mask frame 9, and the protrusion amount of the flare portion 9b was smoothly and continuously changed.

  In the first embodiment, when viewed from a direction parallel to the Z axis, the distance between the inner end of the end surface joined to the funnel 3 of the side wall 1b of the panel 1 and the tip of the flare portion 9b is a length at which the Y axis intersects. The maximum is about 20 mm (dimension CL1 in FIG. 6) at the center of the side, but the minimum is about 10 mm (dimension CLm in FIG. 6) near the boundary between the long side and the corner. This is because the shape of the side wall 1b of the panel 1 when viewed from the direction parallel to the Z axis is not an accurate rectangle, and both the long side and the short side are curved in an arc shape. Further, as shown in FIG. 4, the thickness of the side wall 1b of the panel 1 gradually increases from the end surface joined to the funnel 3 of the side wall 1b of the panel 1 toward the face 1a side in the Z-axis direction. The inner surface of the side wall 1b is inclined so as to gradually approach the Z axis. Accordingly, the distance C between the tip of the flare portion 9b and the side wall 1b of the panel 1 is further smaller than the dimensions CL1 and CLm. However, since the amount of protrusion of the flare portion 9b is set as described above, it is possible to secure the same distance C as the long side center and the short side center in the corner portion. Further, since the flare portion 9b is continuously formed over the entire circumference of the mask frame 9, there is no portion in the mask frame 9 where the rigidity is extremely reduced. Therefore, sufficient strength of the mask frame 9 can be secured.

  In FIG. 6, the broken line indicates the edge shape of the flare portion 9 b of the mask frame 9 according to the comparative example 1 in which the flare portion 9 b having a constant protrusion amount W of 10 mm is continuously formed over the entire circumference of the mask frame 9. ing. Comparative Example 1 is the same as Example 1 except for the protruding amount of the flare portion 9b. In Comparative Example 1, a cross-sectional view taken along line AA in the vicinity of the corner portion is shown in FIG. As shown in FIG. 10, in Comparative Example 1, the flare portion 9b and the side wall 1b of the panel 1 collide in the vicinity of the corner portion.

  The same mask frame 9 as that of Example 1 was produced except that the amount of protrusion WL1, WS1, WD, WLm, and WSm of the flare part 9b from the outer surface of the side wall part 9a was changed (Comparative Examples 2 to 4). About the mask frame 9 of the said Example 1 and Comparative Examples 1-4, it evaluated by the following items.

1. Interval C
The distance C (see FIG. 4) between the flare portion 9b and the side wall 1b of the panel 1 when the mask frame 9 is mounted on the panel 1 was evaluated according to the following criteria. If the interval C is small, the possibility that the operator will come into contact with the panel 1 when the mask frame 9 is attached to and detached from the panel 1 in the manufacturing process increases. When the mask frame 9 and the panel 1 come into contact with each other, the inner wall of the panel 1 is scratched, resulting in a defective product.

  “◯”... There is a sufficient margin and there is no possibility of contact between the two when the mask frame 9 is attached to or detached from the panel 1.

  “Δ”... The margin is not sufficient, and there is a possibility that both may come into contact with each other when the mask frame 9 is attached to and detached from the panel 1.

  “×”... There is no allowance, and when the mask frame 9 is attached to and detached from the panel 1, there is a high possibility that they both come into contact with each other, or they always come into contact.

2. Fitability Evaluation of workability when one worker performs the process of fitting the skirt portion 2d of the shadow mask 2 between the opposite side wall portions 9a of the mask frame 9 without using a jig or the like according to the following criteria. did. If even a part of the skirt portion 2d is caught on the tip of the side wall portion 9a or the flare portion 9b, the fitting workability is lowered.

  “◯”... The skirt portion 2d is not caught over the entire circumference, the shadow mask 2 can be smoothly fitted into the mask frame 9, and the workability is good.

  “Δ”... The shadow mask 2 can be fitted into the mask frame 9 while part of the skirt portion 2d is caught and released by elastically deforming the skirt portion 2d.

  “×”... The skirt portion 2 d is caught and it is difficult to fit the shadow mask 2 into the mask frame 9. Alternatively, even if it can be fitted, there is a high possibility that the shadow mask 2 is broken or deformed, resulting in a defective product.

3. Mask Frame Strength The mechanical strength of the mask frame 9 was evaluated according to the following criteria. When the strength is reduced, the mask frame 9 is easily deformed due to transfer by a robot or handling by an operator in the manufacturing process, and it is not possible to ensure desired quality.

  “◯”... Has a sufficient strength and the mask frame 9 is not easily deformed in the manufacturing process.

  “Δ”... The strength is not sufficient, and there is a possibility that a problem such as deformation of the mask frame 9 may occur depending on how the operator handles the manufacturing process.

  “×”... Insufficient strength, and there is a high possibility that the mask frame 9 is deformed in the manufacturing process.

  The evaluation results for Example 1 and Comparative Examples 1 to 4 are shown in Table 1.

  In the above-described embodiments and examples, the edge shape of the flare portion 9b on the long side and the short side of the mask frame 9 viewed from the direction parallel to the Z axis is a curve that smoothly connects two large and small arcs. However, the present invention is not limited to this, and may be a shape in which two or more straight lines are smoothly connected, a shape in which an arc or a curve other than an arc and a straight line are smoothly connected, and the like. Further, it may have an inflection point as shown in FIG. 5 between the center of the side and the boundary with the corner portion, or may not have an inflection point as shown in FIG. good.

  The field of use of the present invention is not particularly limited, and can be widely used for television receivers, computer displays, and the like.

It is sectional drawing of the color cathode ray tube which concerns on one Embodiment of this invention. 1 is a perspective view showing an outline of a shadow mask structure in which a shadow mask is held on a mask frame in a color cathode ray tube according to an embodiment of the present invention. 1 is a plan view of a panel to which a shadow mask structure is attached in a color cathode ray tube according to an embodiment of the present invention. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. FIG. 4 is an enlarged plan view showing the vicinity of a corner portion of a shadow mask structure attached to a panel in a color cathode ray tube according to an embodiment of the present invention. In the color cathode ray tube which concerns on one Example of this invention, it is the enlarged plan view which showed the corner part vicinity of the shadow mask structure attached to the panel. In the conventional color cathode ray tube, it is a top view of the panel to which the shadow mask structure was attached. In the conventional color cathode ray tube, it is the enlarged plan view which showed an example of the corner part vicinity of the shadow mask structure attached to the panel. In the conventional color cathode ray tube, it is the enlarged plan view which showed another example of the corner part vicinity of the shadow mask structure attached to the panel. It is arrow sectional drawing in the AA line of FIG. 6 about the color cathode ray tube which concerns on the comparative example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Panel 1a Face part 1b Panel side wall 2 Shadow mask 2a Main surface 2b Perforated part 2c Non-perforated part 2d Skirt part 3 Funnel 4 Deflection yoke 5 Electron gun 6 Neck 7 Phosphor screen 8 Shadow mask structure 9 Mask frame 9a Side wall part 9b Flare part 11 Spring 24 Stud pin

Claims (1)

A panel having a phosphor screen formed on the inner surface, a shadow mask disposed opposite to the phosphor screen, a mask frame having a substantially rectangular frame shape for holding the shadow mask, and four corner portions of the mask frame A color cathode ray tube comprising a spring fixed to the inner surface of the side wall of the panel.
The shadow mask includes a main surface having a curved surface protruding to the phosphor screen side, and a skirt portion provided continuously around the main surface and bent to the opposite side of the phosphor screen,
The mask frame includes a side wall portion that comes into contact with the skirt portion of the shadow mask, and a flare portion that is bent at the phosphor screen side end of the side wall portion so as to be closer to the side wall of the panel. With
The flare portion is formed continuously over the entire circumference of the mask frame so as to surround the shadow mask,
The amount of protrusion of the flare from the outer surface of the side wall is WL1 at the center of the long side of the mask frame, WS1 at the center of the short side of the mask frame, WD at the center of the corner of the mask frame, When WLm is near the boundary between the long side and the corner portion, and WSm is near the boundary between the short side and the corner portion of the mask frame,
WL1 ≧ WD> WLm
WS1 ≧ WD> WSm
A color cathode ray tube characterized by satisfying

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