CN86101478A - Shadow mask is through improved chromoscope - Google Patents

Abstract

In improved chromoscope (10), have the scrak type shadow mask (24) that is roughly rectangle a kind of, this shadow mask becomes relativeness to be installed in wherein with the linear screen of the cathodoluminescence that is roughly rectangle (22).Near the interval (A between the adjacent slot stringer of shadow mask minor axis (Y-Y) _H), it is near the Chang Bianchu of shadow mask is less than its major axis.

Description

Shadow mask is through improved chromoscope

The present invention relates to a kind of like this chromoscope, it has the porose shadow mask of clearance type and is installed in the linear screen of cathodoluminescence place near this picture tube, thereby particularly obtains a kind of through improved shadow mask profile to the improvement of shadow mask hole longitudinal separation in this picture tube.

Most of chromoscope of manufacturing at present is linear screen slots shadow mask type.This pipe is the rectangle phosphor screen of spheric profile and is the linear screen that has the cathodoluminescence material, has the lyriform pore formula shadow mask and the phosphor screen of its how many profiles spherical in shape adjacent again.This slit-shaped hole in the pipe longitudinally disposes, and it basic parallel with the minor axis of pipe or perhaps increased its curvature gradually from center to its minor face of shadow mask.

Several improvement projects to chromoscope have been proposed recently.One of these improvement projects are the new ideas to phosphor screen panel profile, and this imagination can produce the sensation on plane.This kind modification to picture tube is disclosed in by RCA Corp.'s (the invention people is F.R.Ragland.Jr.) in 469,772 and 469, No. 774 U.S. Patent applications submitting February 25 nineteen eighty-three.This have along the profile of the long and short axle of phosphor screen panel through improved tube fluorescent screen profile, but non-sphere.Its long and short axle is defined as and is respectively central horizontal and vertical axis when pipe is positioned at its normal viewing location.In the preferable embodiment in these patent applications, the surrounding edge of tube fluorescent screen is actually the plane and is the plane from visually seeing.For realizing this plane or being actually the surrounding edge on plane, the phosphor screen panel must have been made a curvature along its major axis, this curvature is that the side of panel is greater than the center.The aspherical of this phosphor screen panel can produce the problem that relates to the shadow mask profile.If when shadow mask was made the straight cross section that is parallel to along its side minor axis, this shadow mask promptly had bad mechanical property, such as disadvantageous microphonic and (or) the protuberance problem.Therefore shadow mask need be formed in its place, cross section the bigger curvature that is manifested than by this phosphor screen panel is arranged.Yet the improvement of this kind shadow mask profile but needs other changes in the pipe, comprises changing shadow mask lyriform pore style.

In linear screen slots shadow mask type pipe in advance, shadow mask is almost sphere and is maintained fixed constant on shadow mask along the interval (horizontal interval) of the adjacent lyriform pore stringer of major axis.Yet some later stage pipes of this kind pattern comprised having also illustrated as the 4th, 136, No. 300 patents of the U.S. variation that lyriform pore stringer interval can be arranged like that of shadow mask that increases curvature, and this patent right is authorized A.M.MORRELL on January 23rd, 1979.In this type of later stage pipe, the centreline space of adjacent stringer lyriform pore is to increase from center to the edge of shadow mask at interval.This increase generally be along major axis from minor axis with distance square and change.

(invention people is W.D.MASTERTON) the 615th, No. 589 United States Patent (USP) of submitting to by RCA Corp. on March 31st, 1984 weigh once disclosed in the application case a kind of novel lyriform pore capable-between-line spacing.In this application case, between adjacent lyriform pore stringer be at interval with distance shadow mask SWB from biquadratic increase to its side from the shadow mask center.This change list in the stringer at interval can be shown the biquadratic that a coefficient multiply by this distance, coefficient wherein is variable, with regard to being parallel to but leave with regard to the shadow mask cross section of central horizontal axle, this coefficient to be compared to place, cross section on the central horizontal axle for big.This kind biquadratic changes that to have proved that enough first generation roughly are the shadow mask profile of plane picture tube used.The shadow mask of this kind first generation picture tube along its minor axis than bigger in fact along curvature that major axis had.Yet the shadow mask curvature that is parallel to minor axis cross section place reduces and becomes more flat in the side edge of shadow mask to the side of shadow mask from minor axis.This flat be disadvantageous in shadow mask because it is more yielding and have certain unforeseen bending when pipe is made heating when handling.The adjustment to various curvatures in this kind shadow mask is allowed in the improvement of lyriform pore line spacing provided by the present invention, to obtain the bigger curvature of shadow mask side edge.

According to the present invention, this kind color picture tube has the lyriform pore type shadow mask that is roughly rectangle, this shadow mask becomes corresponding relation to be installed in wherein with the linear screen of the cathodoluminescence that is roughly rectangle, and this improvement makes near near being less than its major axis at place, the long limit of shadow mask of the interval between the lyriform pore stringer of shadow mask minor axis.

Fig. 1 (the 1st page) is the shadow mask type color CRT in conjunction with one embodiment of the invention, the plane graph of its section axial section.

The luminescent screen for colour display tube front elevation that Fig. 2 (the 1st page) gets for Fig. 1 center line 2-2 place.

Fig. 3 is the major axis 3a-3a of presentation graphs 2 and the constitutional diagram that the surface profile of phosphor screen panel is located in minor axis 3b-3b cross section for the 2nd page.

Fig. 4 (the 2nd page) is the shadow mask front elevation of Fig. 1 color picture tube.

Fig. 5 (the 2nd page) is the major axis 5a-5a of presentation graphs 4, the shadow mask surface profile constitutional diagram at minor axis 5b-5b and place, diagonal 5c-5c cross section.

Fig. 6 (the 3rd page) for the aperture mask lyriform pore line spacing curve chart represented with solid line and be represented by dotted lines have earlier in the shadow mask lyriform pore at interval.

Fig. 7 (the 4th page) gets the enlarged drawing of shadow mask for Fig. 4 annulus 7 places.

The phosphor screen line curve figure that Fig. 8 (the 5th page) selects for color picture tube.

Fig. 9 (the 4th page) is by the given shadow mask front elevation of phosphor screen curvature, to represent its fixedly outline line of sagitta of arc curvature.

Figure 10 is through improved shadow mask front elevation for the 4th page, to represent its fixedly outline line of sagittal heights.

Fig. 1 represents a rectangular color picture tube 10, and this picture tube has a glass big envelope 11, and this glass big envelope comprises rectangle phosphor screen the panel 12 and one tubular neck 14 that is connected by a funnel 16.This panel watches a phosphor screen 18 and a periphery or sidewall 20 to be formed by one, and this sidewall is sealed in the funnel 16 by a kind of frit 17.22 of a kind of novel rectangle three look cathodoluminescence phosphorus screens are propped up by phosphor screen 18 inner surfaces and carry.This phosphorus screen be the lines screen and with the phosphorus line be stretched to be parallel to pipe slightly minor axis Y-Y(perpendicular to Fig. 1 plane).The profile of phosphorus line will be described in more detail hereinafter.With novel porous colour selection electrode or shadow mask 24, to be installed in movably in the screen 12 with 22 one-tenth predetermined spaced relationships of screen.Linear electron gun 26 shown in dotted lines in Figure 1 is installed in central authorities in the neck 14, with produce and guide three electron beams 28 along originally be the tangent line path of common plane by shadow mask 24 to phosphorus screen 22.

The picture tube 10 of Fig. 1 is to be designed to cooperate an external magnetic deflecting coil to use, this coil 30 as shown in the figure near its composition surface around neck 14 and funnel 16, with so that three electron beams 28 be controlled by in vertical and the horizontal magnetic force line so that in the rectangular light territory of electron beam on phosphorus screen 22 respectively at doing horizontal sweep in major axis (X-X) direction and in minor axis (Y-Y) direction, making vertical scanning.

Fig. 2 represents the front of phosphor screen panel 12.The outer surface of panel 12 constitutes the rectangle that has little Qu Bianyuan.The border of screen 22 is represented by dotted lines in Fig. 2.This screen border is a rectangle.The relative profile of the phosphor screen panel 12 outer surfaces comparison sheet along minor axis (Y-Y) and major axis (X-X) is shown among Fig. 3.The outer surface that makes phosphor screen panel 12 is along long and short axis bending, and make in the middle body of panel 12 its along the curvature of minor axis greater than curvature along major axis.Say for example in fluoroscopic center, along the outer surface profile radius of major axis with along the ratio of minor axis radius greater than 1.1(greater than percent 10 difference).Yet, but be in the middle body of panel, near the edge of panel, to greatly increase for little along the curvature of major axis.In this embodiment, along major axis and near the curvature at phosphor screen edge greater than general curvature along minor axis.Plant design in view of the above, the phosphor screen middle body becomes more flat, and in fact the each point of phosphor screen outer surface is positioned at a plane P and defines one and be the surface profile line of rectangle substantially at the screen edge place.To selecting along cornerwise this surperficial curvature, can be smoothly along the transformation between the different curvatures of major axis and minor axis.Preferably make curvature along minor axis in the phosphor screen middle body greater than along the curvature of major axis about 4/3rds.

By adopting different curvatures, make direct each point on the panel outer surface at phosphor screen 22 edges all in fact be positioned at same plane P along long and short axle.These each point outline lines that (as shown in Figure 2) then constitutes on the panel outer surface when the top view of autofluorescence screen panel 12 that are roughly on the plane also are essentially the rectangle that is overlapped on fluorescent screen 22 edges.So, when inserting pipe 10 in the television receiver, a kind of mask of even width or instrument bezel (bezel) can be used in around the pipe.This kind instrument bezel edge at rectangular profile line place contact pipe also will be located substantially in the plane P.Because it presents the plane in the border on every side the picture on the teletron screen, so produce a kind of illusion, even the phosphor screen panel is outwardly-bent along long and short diaxon, its picture still is flat.

Fig. 4 represents the front elevation of this novel shadow mask 24.Dotted line 32 expression shadow masks 24 lyriform pore portion boundaries.Now along major axis (X-X), minor axis (Y-Y) and shadow mask 24 cornerwise surface profiles are curve 5a respectively, and 5b and 5c are illustrated among Fig. 5.The curvature that shadow mask 24 is had along its major axis with different along its minor axis.The curvature that profile had along major axis is less and bigger at its boundary near the shadow mask center.The method that generally obtains this kind shadow mask profile is that major axis (X-X) curvature is partly plotted the circle that a greater part of footpath is round and plot a small radii at the remainder of major axis in the centre approximately therein.Yet more specifically say, be actually along the sagittal heights of major axis that biquadratic with distance minor axis (Y-Y) distance changes.Sagittal heights is exactly the distance with the tangent imaginary plane of shadow mask centre of surface.This curvature that is parallel to minor axis (Y-Y) can make the more adaptive required shadow mask periphery of major axis curvature and can comprise a kind of as changing along the used curvature of major axis.Because increased near the curvature the major axis end, this kind shadow mask profile presents certain good thermal expansion character.This discussed in the 4th, 136, No. 300 patents of the above-mentioned U.S. to produce good thermal expansion character by increasing curvature.

In the curve of Fig. 6 with shown in the solid-line curve and that indicate " H " is the lyriform pore line spacing A in a certain quadrant in this kind shadow mask 24 _H, and in a certain quadrant of shadow mask according to the 615th, No. 589 manufacturing of above-mentioned U.S. Patent application, be represented by dotted lines and indicate the lyriform pore line spacing A of " F " _HCurve chart.The vertical coordinate representative of this curve chart is apart from the distance of major axis.Horizontal coordinate is represented row one between-line spacing of lyriform pore, and as shown in Figure 7, this is to measure from the center line of a certain stringer to adjacent stringer center line at interval.With each curve numbering, with the interval of identification from the minor axis of its representative.Say for example, indicate 200 each Curves Recognition the 200th and the interval between the 201st stringer.

By having earlier in the shadow mask shown in the dotted line, row one between-line spacing of this kind lyriform pore along and be uniformity during near minor axis, shown in straight curve " F "-1 and " F "-150.Can from lines " F " 200, see slight curvature, to represent that 200 row one between-line spacing has increase slightly along with the distance of distance major axis at interval.Wherein there is visible bending curve " F "-300 and " F "-306, are to come along with the increase distance of distance major axis with the actual increase in expression row one between-line spacing.

This kind novel through the capable between-line spacing of improved shadow mask lyriform pore with before shadow mask quite inequality near the minor axis place.As shown in Figure 6, near the capable between-line spacing A of lyriform pore of minor axis _HBe along with from curve " H "-1, the distance of the increase of major axis shown in " H "-50 and " H "-100 and reducing.During near the 150th interval, the capable between-line spacing of this lyriform pore then increases a little with the increase distance of distance major axis, shown in the slight bending in the curve " H "-150.This bending of representing the curve of the capable between-line spacing of lyriform pore is to increase along with the distance of distance minor axis, shown in curve " H "-200 and " H "-300, but edge reduces a little at shadow mask, just like curve " H "-305 and curve " H "-300 are compared gained.

Along the capable between-line spacing of lyriform pore of major axis approximately with the distance SWB from the biquadratic function and increase.In special example shown in Figure 6, change to be approximately A=30+0.00135X in this kind major axis of mil ⁴Yet when leaving major axis, this lyriform pore is capable-and between-line spacing changes more complicated and written agreement equation A=a+bx greatly ²+ cx ⁴And change, a in the formula, b and c are the different functions apart from the square distance of major axis, x be apart from SWB from.

Make the phosphor screen 22 of picture tube 10 with a kind of known method for imaging, this kind method for imaging adopts shadow mask 24 as photography body.A problem can take place when linear light sorurce being used for the step of exposure of method for imaging.This problem promptly is that the image of linear light sorurce is aimed at wrong with the center line of phosphorus line.This mistake that is referred to as " tiltedly understanding error " aligns can widen the light intensity distribution that is used for printing the phosphorus line, thereby has also increased the sensitivity of phosphorus matter width to exposure, and this becomes more difficult with regard to making the control to line thickness.In prior art, existing some devices can be finished the oblique meeting of this kind compensation of error, comprise a kind of belt exposure technique that the inclination of linear light sorurce and exposing successively of different phosphor screens district is synchronous and make the lyriform pore stringer and phosphorus line warpage, the former authorizes people's such as SUZUKI United States Patent (USP) the 3rd as on June 10th, 1975, shown in 888, No. 673, the latter authorized people's such as SUZUKI United States Patent (USP) the 3rd as on June 10th, 1975, shown in 889, No. 145.In this novel picture tube 10, solve tiltedly can problem method for a change lyriform pore row one between-line spacing with as apart from SWB from the function of distance major axis apart from the two.The resulting phosphorus line graph of this result comprises the lines of warpage in a certain zone of phosphor screen and the straight line at phosphor screen side place, the oblique meeting error maximum at the former place, and the oblique of latter place can the error minimum in this picture tube.This diagrammatic representation is in Fig. 8, and wherein solid line 40 to 45 is represented selected relevant phosphorus line, and dotted line 46 representatives are parallel to the straight line of minor axis.As seen in Fig., the curvature of phosphorus line increases along with the increasing of distance minor axis distance, till near the maximum degree of curvature of lines 42 in the lines 43, reduce then until terminal lines 45 during for straight line only.

One of novel lyriform pore stringer advantage at interval is, its use allow near shadow mask side cross section and be parallel to the shadow mask curvature of minor axis can be bigger than untapped.Has the shadow mask profile that the phosphor screen panel profile that roughly is horizontal edge is provided, shown in the lines 50 of Fig. 9.Outline line on the shadow mask 52 of the equal sagittal heights of lines 50 representatives.Have as can be seen: lines 50 are essentially straight line at shadow mask left and right sides place.This straight line can produce actual manufacturing and handling problem.Say that for example the slight contact on the shadow mask may make it become and curve inwardly when normal process.So, shadow mask need be had big curvature in its side edge design, in case problem occurs here.Admit of through improved shadow mask profile, shown in the lines among Figure 10 54 when adopting this novel lyriform pore stringer at interval.Outline line on the shadow mask 56 of the equal sagittal heights of lines 54 representatives.In this kind situation, as can be seen lines 54 be actually at limit, shadow mask left and right sides place crooked, thereby make it that the big curvature that is parallel to minor axis be arranged, therefore greater strength is provided.

Claims (4)

1, a kind of color kinescope (10), comprise the shadow mask of being installed in abutting connection with cathodoluminescence line screen (22) (24), this shadow mask comprises that it is positioned at the some crack bar shaped lyriform pores between stringer, this shadow mask has one and is the periphery of similar rectangle substantially and two long relatively limits and two relative short edges are arranged, the major axis of this shadow mask (X-X) is for by its shadow mask center and stretch to the axis of minor face mid point, the minor axis of shadow mask (Y-Y) is for by its shadow mask center and stretch to the axis of long limit mid point, described lyriform pore stringer generally is in continuity and spaced apart on long axis direction on the short-axis direction, it is characterized in that: near the capable between-line spacing (A of lyriform pore of shadow mask minor axis _H), be in the long limit of shadow mask place less than near its major axis.

2,, it is characterized in that row-between-line spacing (A of lyriform pore according to the picture tube that claim 1 limited _H), near near being greater than the major axis (X-X) on each angle of shadow mask (24).

3, according to the picture tube that claim 1 limited, it is characterized in that along being parallel to major axis (X-X) but break away from the lyriform pore in major axis cross section capable-between-line spacing (A _H) be approximately according to equation A=a+bx ²+ cx ⁴And change, A is a row-between-line spacing in the formula, and a, b and c are the different functions apart from the major axis square distance, and x is the distance apart from minor axis Y-Y.

4, according to claim 1 or 3 picture tubes that limited, it is characterized in that the lyriform pore along major axis is capable-between-line spacing approximately according to apart from SWB from the biquadratic function and increase.

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