JPH02117048A - Exposure device for color kinescope - Google Patents

Abstract

PURPOSE:To obtain dots of a fluorescent substance as desired in size by providing a mechanism which moves the height of a slit up and down in accordance with the rotating angle of a luminescent tube. CONSTITUTION:A light source section 1 includes a lamp house section 100 equipped with an ultra high pressure mercury lamp 104 and a drive section 105 which rotates the lamp house section 100 around a pipe shaft 6. And the lamp house section 100 is equipped with a mechanism which permits the height of a slit 22 to be moved up and down in accordance with the rotating angle of the mercury lamp 104 driven by the drive section 105 by means of a slide shaft 102 and a guide shaft 103 connected with the aforesaid shaft with an eccentric cam 101 rotated, which is fixed onto a motor 106. The ultra high pressure lamp 104 is therefore rotated around the pipe shaft 6 even if there exists the local difference in the luminous energy of the luminescent section of the ultra high pressure mercury lamp 104 of the light source section 1. By this constitution, the dot of a fluorescent substance can thereby be obtained as desired in size without the local change in the size of the dot of the fluorescent substance on both surfaces.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a light source for an exposure apparatus used for forming a fluorescent screen of a color cathode ray tube.

[Conventional technology]

Conventionally, this type of lightless device uses an ultra-high pressure mercury lamp 26 as an arc tube, and has a slit 22 in the circumferential direction, as shown in FIGS. 2(a) and 2(b). The width is approximately the same as the width of the light emitting part of the arc tube 26.
It was equipped with cooling water inlet/outlet ports 25a, 25b and quartz glass 24 for cooling, and was used with a fixed light source.

The structure of an in-line color cathode ray tube and a manufacturing method using a haze light device using this light source will be described below.

FIG. 3 is a schematic cross-sectional view of a color cathode ray tube, showing three electron beams IIA and IIB emitted from an electron gun.

11C is scanned over the entire surface of one screen by the deflection magnetic field of the deflection yoke 12, and collides with the corresponding phosphor dots through the shadow mask apertures 13, thereby emitting a desired color and forming a color image.

If the electron beam passing through the shadow mask aperture 13 collides accurately with the phosphor dot, the desired luminescent color will be produced, but there is an error in which the phosphor dot is not placed accurately at the position where the electron beam reaches, generally due to mis-landing. When the error called . . . increases, adjacent phosphor dots also emit light, reducing color purity. Therefore, in the exposure process to form a phosphor screen on the inner surface of the face panel, an optical correction plate is installed in the exposure system so that the final trajectory of the electron beam to the phosphor dots matches the exposure light beam that arranges the phosphor dots. ing. Fourth
The figure shows an exposure optical system for arranging phosphor dots corresponding to the central electron beam 11B. The optical correction plate 18B is
It has a curved surface that corrects the exposure light beam emitted from the light source in the light source section @10 to a trajectory 17B where the electron beam deflected by the deflection magnetic field is incident on the shadow mask aperture 13. Furthermore, the exposure optical system has a light amount correction plate 19B.

In order to make the size of the phosphor dots on the screen a desired size, for example, the amount of exposure light is adjusted so that it is uniform over the entire screen.

[Problem to be solved by the invention]

The conventional exposure equipment mentioned above generally uses an ultra-high-pressure mercury lamp as the arc tube, but since ultra-high-pressure mercury lamps have local differences in light intensity in the light emitting part, the light intensity correction plate is used to adjust the size of the phosphor on the screen. In some cases, it was not possible to adjust the size to the desired size. For example, as shown in Fig. 5, if the phosphor dots become larger at the upper left and lower right of the screen, and the phosphor dots become smaller at the upper right and lower left of both sides, the light amount correction plate should be corrected.
You can reduce the light intensity to make it smaller at the top left and bottom right where the phosphor dots are large, and increase the light intensity to make it larger at the top right and bottom left where the phosphor dots are small, but the amount of light correction varies greatly depending on the location of the light intensity correction plate. Therefore, it has become extremely difficult to manufacture a light amount correction plate with stable characteristics.

One way to solve this problem is to cover each arc tube with a light-shielding sleeve that has slits in one circumferential direction, and rotate it around an axis perpendicular to the tube axis of the arc tube. The difference in light intensity was removed, and the amount of light intensity correction was extremely small.

However, when the arc tube is rotated around an axis perpendicular to the tube axis of the arc tube, the optical correction plate used in conventional exposure optical systems that fixed the arc tube cannot be used, which is an inconvenience. occurred. As shown in Figure 6(a),
In the ultra-high pressure mercury lamp provided with the slit 29, in a cross section perpendicular to the tube axis of the ultra-high pressure mercury lamp, the light source center is located at the tube axis 20, but in a plane including the tube axis of the ultra-high pressure mercury lamp, the light source center is located at the 6th position.
The position of the slit opening 21 is as shown in FIG. 2(b).

Therefore, in an exposure apparatus in which the tube axis of the ultra-high-pressure mercury lamp is set in the horizontal direction of the screen, the horizontal light source center of one screen is the position of the tube axis 20 of the ultra-high-pressure mercury lamp with respect to the vertical light source center of the screen. 1 - 9 surfaces are approached by the difference in the position of the aperture 21. In other words, for light sources with different light source center positions in the horizontal and central directions of the screen, an optical correction plate is used to correct the exposure light source so that it follows the trajectory of the electron beam deflected by the deflection magnetic field. are doing.

However, in exposure equipment that has a light source that covers an ultra-high-pressure mercury lamp with a light-shielding sleeve with slits in the circumferential direction and rotates the ultra-high-pressure mercury lamp around an axis perpendicular to the tube axis of the ultra-high-pressure mercury lamp, the horizontal and vertical directions of one screen are Since the difference in the center of the light source disappears, in order to construct an equivalent exposure optical system, the correction amount of the optical correction plate used in the exposure equipment that fixed the ultra-high pressure mercury lamp must be adjusted, for example, in the horizontal direction on both sides. Therefore, it became necessary to change the ultra-high pressure mercury lamp so that the tube axis position and the slit opening position were moved forward by the difference.

An object of the present invention is to provide an exposure apparatus for a color picture tube that solves the above problems.

[Means to solve the problem]

To achieve the above object, the present invention covers a cylindrical arc tube with a light-shielding sleeve having slits in the circumferential direction, and rotates the light source around an axis perpendicular to the tube axis of the arc tube to obtain a point light source. The device is equipped with a mechanism that raises and lowers the slit height in accordance with the rotation angle of the arc tube.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

(Example 1) FIGS. 1(a) to (c) are diagrams showing Example 1 of the present invention.

As shown in FIG. 1(a), the light emitted from the light source section 1 passes through the optical correction plate 2 and the light amount correction plate 3, reaches the inner surface of the panel 4 provided with the shadow mask 5, and is exposed. As shown in FIG. 1(b), the light source section 1 includes a lamp house section 100 having an ultra-high pressure mercury lamp 104, and this lamp house section 100.
It has a drive unit 105 that rotates the tube around the tube axis 6.

In addition, the lamp house section 100 adjusts the height of the slit 22 in accordance with the rotation angle of the mercury lamp 104 by the drive section 105 by rotating an eccentric cam 101 attached to a motor 106 and moving it up and down by a slide shaft 102 and a guide shaft 103 connected thereto. Equipped with a mechanism to The motor 106 is controlled by the rotation angle of the rotary drive unit 105, and
2 is determined by the shape of the eccentric cam 101.

In the exposure apparatus of the present invention, even if there is a local light intensity difference in the light emitting part of the ultra-high pressure mercury lamp 104 in the light source part, the ultra-high pressure mercury lamp 104 rotates around the tube axis 6, so that the phosphor dots on the screen can be Fluorescent dots of a desired size can be obtained without locally changing the size. Furthermore, in order to rotate the ultra-high-pressure mercury lamp, for example, the optical correction plate used in exposure equipment that uses a fixed ultra-high-pressure mercury lamp as a light source, aligns the tube axis of the ultra-high-pressure mercury lamp with the horizontal direction of the screen.
Although it was no longer usable in the past, it was used in an exposure optical system that aligned the tube axis of the ultra-high pressure mercury lamp in the horizontal direction of the screen by moving the slit 22 of the ultra-high pressure mercury lamp up and down in synchronization with the rotation of the ultra-high pressure mercury lamp. Optical correction plates can now be used.

(Example 2) FIGS. 1(d) and (e) are diagrams showing Example 2 of the present invention.

In this embodiment, instead of changing the height of the slit 22 with the eccentric cam 101, the saddle-shaped curved surface 107 is
2, the height of the slit 22 is changed.

This embodiment has the advantage that the structure of the vertical mechanism for the slit 22 can be simplified.

〔Effect of the invention〕

As explained above, the present invention easily eliminates local differences in light intensity that exist in arc tubes such as ultra-high pressure mercury lamps by rotating the arc tube and using a light intensity correction plate to achieve a desired size of phosphor dot. The arc tube is covered with a light-shielding sleeve that has slits in the circumferential direction of the arc tube, rotates around an axis perpendicular to the axis of the arc tube, and moves the slit height up and down in synchronization with the rotation angle. This has the effect of making it possible to use the optical correction plate conventionally used in exposure apparatuses in which the arc tube was fixed.

[Brief explanation of drawings]

FIG. 1(a) is a sectional view showing Embodiment 1 of the present invention, FIG. 1(b)
is an enlarged view of the light source section, (C) is a side view of the same, FIG. 1(d) is an enlarged view showing Example 2 of the present invention, (e) is a side view of the same, and FIGS. ) is a diagram showing the light source section of a conventional exposure device, Figure 3 is a diagram showing the structure of an in-line color cathode ray tube,
Figure 4 is an explanatory diagram showing an optical system that exposes dots corresponding to the central beam, Figure 5 is a diagram showing an example in which the sizes of the phosphor dots are not the same at the four corners of the screen, and Figure 6 (a) is Diagram showing the center of the light source in a plane perpendicular to the tube axis of a light source with a slit, (
b) is a diagram showing the center of the light source in a plane including the tube axis. 1...Light source part 3...Light amount correction plate 5...Shadow mask 10...Light source position 12...Deflection yoke 17B...Exposure light beam locus 19B, 20...Tube of ultra-high pressure mercury lamp Axis 21.23...
・Slit opening 22.29...Slit 2.18B
...Optical correction plate 4...Panel 6...Tube axis 11A, IIB, IIC...Electron beam 13...Shadow mask aperture 24...Quartz glass 26.104...Ultra high pressure mercury lamp 100...Lamp house part 102...Slide shaft 105...Rotation drive part 107...Hill-shaped curved surface

Claims (1)

[Claims] (1) In an exposure device that obtains a point light source by covering a cylindrical arc tube with a light-shielding sleeve having slits in the circumferential direction and rotating the light source around an axis perpendicular to the tube axis of the arc tube, rotation of the arc tube is performed. An exposure device for a color picture tube characterized by being equipped with a mechanism for raising and lowering the slit height according to the corner.