JPS6330731B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color picture tube, and more particularly to a color picture tube that has improved light absorption characteristics for external light and can provide image quality with good contrast.

FIG. 1 shows a cross-sectional view of a conventional color picture tube. There is a funnel 10 made of a funnel-shaped glass container, and a panel 11 is attached to the wide opening of the funnel 10.
are joined by frit glass 13.
The inner surface of the panel 11 has a phosphor surface 14 consisting of three colored phosphor dots or stripes, the upper surface of which is lined with a thin aluminum film 15. A shadow mask 16, which is a color selection electrode, is installed at a predetermined distance from the fluorescent surface 14.
An internal conductive film 17 made of a mixture of water glass and graphite particles is coated almost entirely on the inner surface of the funnel portion of the funnel 10 . A three-electron gun 20 that focuses electron beams and fires them at high speed is sealed in the neck portion 18 of the funnel 10. 3
A spacer 21 is welded to the most extreme electrode of the electron gun 20, and this spacer 21 is in contact with the internal conductive film 17. Furthermore, a getter 23 is attached to the most advanced electrode of the three-electron gun 20 via a spring 22. An anode button 19 is embedded in the funnel 10, and the high voltage applied to the anode button 19 is applied to the internal conductive film 1.
7 and the spacer 21 to the accelerating electrode of the electron gun 20. Further, the high voltage is also applied to the shadow mask 16 and the aluminum thin film 15 via a conductive spring (not shown).

FIG. 2 shows an enlarged view of the fluorescent surface 14 of the color picture tube shown in FIG. The phosphor surface 14 includes a striped red phosphor element 31 and a green phosphor element 3.
2. Blue phosphor elements 33 are regularly arranged at a predetermined distance from each other. A light-absorbing material 34 made of graphite is coated between each phosphor element in order to absorb a portion of the external light incident on the phosphor surface 14. The electron beam emitted from the red electron gun of the three electron guns 20 passes through the shadow mask 16 and hits the red phosphor element 31 of the phosphor surface 14, emitting red light.
Similarly, the electron beam emitted from the green electron gun impinges on the green phosphor element 32, and the electron beam emitted from the blue electron gun impinges on the blue phosphor element 33, resulting in green and blue emission colors.

Conventionally, in order to increase the contrast of a color picture tube, in addition to the effect of reducing external light reflectance by the light absorbing material 34, each phosphor element 31, 32, 33 was used.
Coloring pigments are mixed in to further reduce the reflection of external light. That is, the red phosphor element 31 contains a red colored pigment, the green phosphor element 32 contains a green colored pigment, and the blue phosphor element 33 contains a blue colored pigment. Therefore, the red phosphor element 31 absorbs the red component of the external light incident on the phosphor surface 14, the green phosphor element 32 absorbs the green component, and the blue phosphor element 33 absorbs the blue component. Each of these is absorbed, and the reflectance of external light decreases accordingly, improving contrast.

By the way, color picture tubes are generally subjected to heat treatment at a maximum temperature of about 450° C. in the manufacturing process after coating the fluorescent surface. Therefore, the coloring pigment of the conventional colored pigment-containing phosphor cannot be used unless it is an inorganic pigment that is stable against such high-temperature heat treatment, and the concentration of the coloring pigment is low and the light absorption effect is not sufficient. There was a drawback.

This invention was made to eliminate the above-mentioned drawbacks, and uses a new mechanism different from that of conventional color picture tubes to use a coloring substance with a higher concentration.
The object of the present invention is to provide a color picture tube that can provide image quality with good contrast.

An embodiment of the present invention will be described below with reference to FIG.

A panel 11 is joined to the wide opening of the funnel 10 by a fritted glass 13 as in the case of the conventional color picture tube shown in FIG. It is composed of fiber glass 12. On the inside of this optical fiber glass 12 (on the electron gun side), there is a second
Red phosphor element 31, green phosphor element 32, and blue phosphor element 33 shown in the figure
A fluorescent surface 14 consisting of is coated. In the case of the color picture tube of this invention, the light absorbing material 34 of FIG. 2 is not necessarily required. The upper surface of the fluorescent surface 14 is lined with an aluminum thin film 15, similar to conventional color cathode ray tubes, and a shadow mask 16, which is a color selection electrode, is installed at a predetermined distance from the fluorescent surface 14. Further, the internal conductive film 17 is coated on the inner surface of the funnel part of the funnel 10, and the three-electron gun 20 is sealed in the neck part 18.The structure is the same as that of the conventional color picture tube shown in FIG. be.

A colored plate 24 in which three colors of red, green, and blue are arranged in a mosaic pattern is attached to the outside of the optical fiber glass 12. When the fluorescent surface 14 has three-color stripes as shown in FIG. 2, the colored plate 24 is also composed of three-color striped colored elements corresponding to the three-color stripes. Red coloring element 4 of the coloring plate 24 shown in FIG.
1. The green colored element 42 and the blue colored element 43 are the red phosphor element 31, the green phosphor element 32, and the blue phosphor element 33 of the phosphor surface 14 consisting of three color stripes shown in FIG. They are arranged to correspond to the same size and shape. Further, a black light-absorbing material 44 is applied between each of the colored elements 41, 42, and 43.

When the electron beam irradiated from the three-electron gun 20 hits the fluorescent surface 14 and the red, green, and blue phosphor elements 31, 32, and 33 emit light, the light from the red phosphor element 31, for example, becomes an optical In order to pass through the fiberglass 12, the light reaches the colored plate 24 without being diffused, and the red colored elements 4 of the same shape reach the colored plate 24.
Only 1 is passed. Similarly, the light from the green phosphor element 32 illuminates the green colored element 42, and the light from the blue phosphor element 33 illuminates the blue colored element 4.
Pass only 3. The colored plate 24 has the function of absorbing a portion of light incident from the outside and improving contrast. That is, the colored plate 24 detects the red component of external light incident on the red colored element 41, the green component of external light incident on the green colored element 42, and the blue color of external light incident on the blue colored element 43. Regarding external light incident on the black light absorbing element 44, the black light absorbing element 44 absorbs light in the entire visible range. Therefore, the contrast of the color picture tube of the present invention is improved by the amount of external light incident on the colored plate 24 that is absorbed by each colored element. The colored plate 24 can be made using, for example, well-known photographic techniques. That is, a colored plate 24 of a color photosensitive plate similar to a normal color positive film is attached to the front surface of the optical fiber glass 12 of the color picture tube of the present invention in a dark room, and then the electron gun 2 is attached.
An electron beam is irradiated from zero to cause the three-color phosphor elements 31, 32, and 33 on the phosphor surface 14 to emit light. These three color phosphor elements 31, 32, 3
Since the light emitting element No. 3 passes through the optical fiber glass 12, the light reaches the colored plate 24 of the color photosensitive plate without being diffused. As a result, the three-color phosphor element 3 of the phosphor surface 14
Images having the same shape as 1, 32, and 33 are formed on the color photosensitive plate and exposed. When the colored plate 24 of the photosensitive plate exposed in this way is removed from the color picture tube and developed, the three-color phosphor elements 31, 3
Three-color colored element 41 with the same shape as 2 and 33,
42 and 43 are completed. The parts that are in the shadow of the shadow mask 16 and are not exposed to light are finished in black. The colored plate 24 produced as described above is attached to the front surface of the color picture tube of the present invention so that the phosphor elements 31, 32, 33 and the colored elements 41, 42, 43 are aligned with each other. As mentioned above, the coloring plate 24 is installed after the color picture tube is completed.
4 is not exposed to high temperatures. Therefore,
Since there is no restriction that only inorganic pigments that are stable to high temperatures can be used, unlike conventional colored pigment-containing phosphors, pigments with higher color density can be used. For example, organic materials such as those used in ordinary photographic film can also be used. therefore,
Compared to conventional color picture tubes using colored pigment-containing phosphors, the color picture tube of the present invention has the feature of being able to obtain higher contrast.

In the description of this invention, the three-color phosphor elements 31, 32, 33 of the phosphor surface 14 and the three-color colored elements 41, 42, 43 of the colored plate 24 are arranged in a striped shape as shown in FIGS. 2 and 4. Although it was explained as
The shapes shown in Figures 4 and 4 do not limit the scope of the invention.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional color picture tube, FIG. 2 is a partially enlarged view of its fluorescent surface, FIG. 3 is a sectional view of a color picture tube according to an embodiment of the present invention, and FIG. 4 is a partially enlarged view of a colored plate of the color picture tube shown in FIG. 3. FIG. 12...Optical fiber glass, 14
...Fluorescent surface, 16...Shadow mask, 20...
3 electron gun, 24... colored plate, 31... red phosphor element, 32... green phosphor element, 3
3... Blue phosphor element, 41... Red colored element, 42... Green colored element, 43
...Blue colored element. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. In a color picture tube having a fluorescent surface of three color dots or stripes, a shadow mask of a color selection electrode, and three electron guns, the glass surface to which the fluorescent surface is applied is formed of optical fiber glass. A color picture tube, further comprising a colored plate made of colored elements in the form of dots or stripes of three colors, provided on the front surface of the optical fiber glass. 2. The color image receiving device according to claim 1, wherein the colored elements of the three-color dots or stripes of the colored plate correspond to the three-color dots or stripes of the fluorescent surface in the same or almost the same shape and dimensions as the three-color dots or stripes. tube.