JPH0294227A - Exposure apparatus for color picture tube - Google Patents

Abstract

PURPOSE:To make is possible to utilize an optical compensator conventionally used for an exposure apparatus where a light emitting tube is fixed by providing a slit which is rotated in synchronism with the rotation of a light emitting tube disposed in parallel with the axis of the light emitting tube, and moving a light source up and down in accordance with the rotational angle of the light emitting tube. CONSTITUTION:A slit 7 formed in parallel with the axis 6 of a superhigh pressure mercury lamp 104 is rotated in synchronism with the rotation of the lamp 104. When the upper and lower portions of a picture plane are exposed to light, a light source 1 is advanced toward a panel 4 on the axis 6 by an eccentric cam 101 in synchronism with the rotation of the slit 7. Therefore, it is possible to utilize an optical compensator 3 used for an optical exposure system where the axis of a superhigh pressure mercury lamp is in the horizontal direction of a picture plane.

Description

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

[Conventional technology]

Conventionally, as shown in FIGS. 2(a) and 2(b), in this type of exposure apparatus, an ultra-high pressure mercury lamp 26 is used as an arc tube, and a slit 22 is provided in the circumferential direction of the arc tube. The width is approximately the same as the width of the light emitting part of the light emitting part, and cooling water inlets and outlets 25a and 25b and quartz glass 2 are provided to prevent heat generation of the light emitting tube.
4, and the light source was used in a fixed manner.

The structure of an in-line color cathode ray tube and a manufacturing method using an exposure apparatus using this light source will be described below. FIG. 3 is a schematic cross-sectional view of a color cathode ray tube. Three electron beams 11A, 11B, and 11C emitted from an electron gun are scanned over the entire screen by the deflection magnetic field of the deflection yoke 12, and the shadow mask apertures. By colliding with each corresponding phosphor dot through 13, a desired luminescent color is generated and a color image is formed. Reference numeral 10 indicates the position of the light source. If the electron beam passing through the shadow mask aperture 13 collides with the phosphor dots, the desired luminescent color will be produced, but the phosphor dots must be placed precisely at the position where the electron beam reaches. If the error (generally called mislanding) becomes large, adjacent phosphor dots will 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. FIG. 4 shows an exposure optical system for arranging phosphor dots corresponding to the central electron beam 11B. The optical correction plate 18B has a curved surface that corrects the exposure light beam emitted from the light source located at the light source position 10 to a trajectory 17B of the electron beam deflected by the deflection magnetic field and incident on the shadow mask aperture 13.

Furthermore, a light amount correction plate 19B is provided in the exposure optical system so that the size of the phosphor dots on the screen becomes a desired size.
For example, the amount of exposure light is adjusted so that it is uniform across the entire screen.

[Problem to be solved by the invention]

In the conventional exposure apparatus described above, for example, when an ultra-high-pressure mercury lamp is used as an arc tube, there are local differences in light intensity in the light-emitting part of the ultra-high-pressure mercury lamp. Sometimes the size could not be adjusted to the desired size.

For example, as shown in Figure 5, if the phosphor dots become larger at the top left and bottom right of the screen G, and become smaller at the top right and bottom left of the screen, the light intensity correction plate can be adjusted by adjusting the phosphor dots. The amount of light can be decreased so that it becomes smaller in the upper left and lower right where the phosphor dots are large, and the light amount can be increased so that it becomes larger in the upper right and lower left where the phosphor dots are small, but since the amount of light amount correction varies greatly depending on the part of the light amount correction plate, It has become extremely difficult to manufacture a light amount correction plate with stable characteristics.

One way to solve this problem is to cover the arc tube with a light-shielding sleeve that has slits in the circumferential direction, and rotate it around an axis perpendicular to the tube axis of the arc tube. This method has been used to eliminate differences in light intensity, and the amount of light intensity correction has been extremely small.

However, when the arc tube is used by rotating it around an axis perpendicular to the tube axis of the arc tube, the optical correction plate used in the conventional exposure optical system, which fixed the arc tube, is no longer used. This is because the center of the light source is located at the tube axis position 20 in the cross section perpendicular to the tube axis of the ultrahigh pressure mercury lamp provided with the slit 29 as shown in FIG.
However, in a plane including the tube axis, the slit hole 21 is located as shown in FIG. 6(b). 28 is the tube wall of the ultra-high pressure mercury lamp. Therefore, in an exposure device in which the tube axis of the ultra-high pressure mercury lamp is set in the horizontal direction of the screen, the center of the light source in the horizontal direction of the screen is the center of the light source in the vertical direction. It is closer to the screen by a difference of position 21. In other words, for light sources with different optical center positions in the horizontal and vertical directions of the screen, an optical correction plate is used to adjust the exposure light beam to the trajectory of an electron beam deflected by a deflection magnetic field. It is being corrected.

However, in exposure equipment that covers an ultra-high-pressure mercury lamp with a light-shielding sleeve with slits in the circumferential direction and rotates it around an axis perpendicular to the tube axis of the ultra-high-pressure mercury lamp, the difference in the center of the light source in the horizontal and vertical directions of the screen is Therefore, in order to configure an equivalent exposure optical system, it is necessary to change the amount of correction of the optical correction plate used in the exposure equipment that fixed the ultra-high pressure mercury lamp, for example, in the horizontal direction of the screen, to the amount of correction of the ultra-high pressure mercury lamp. It was necessary to change the position so that the difference between the position of the tube axis and the position of the slit opening was at the rear.

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 a light source formed by filling the space with a coolant around an axis perpendicular to the tube axis of the arc tube. An exposure device used as a point light source with a slit that rotates in synchronization with the rotation of the arc tube parallel to the tube axis of the arc tube, and a mechanism that moves the light source position up and down in accordance with the rotation angle of the arc tube. It is.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1(a) is a schematic sectional view of one embodiment of the present invention, FIGS. 1(b) and (C) are enlarged schematic views of the light source section, and FIG. 1(d)
) is a view of the light source section viewed from above the slit.

As shown in FIG. 1(a), the light emitted from the light source section 1 passes through the slit 7, the optical correction plate 2, the light amount correction plate 3,
The inner surface of the panel 4 provided with the shadow mask 5 is irradiated and exposed. The light source section is shown in Figure 1(b),
As shown in (C), a lamp house section 100 having an ultra-high pressure mercury lamp 104, a drive section 105 that rotates the lamp house section 100 around the tube shaft 6, and a motor 106.
By rotating the eccentric cam 101 attached to the rotary drive unit 105 and moving the slide shaft 102 up and down,
and move the Langhaus section 100 up and down. In addition, in order to make this vertical movement smooth, the motor 106 is controlled by the rotation angle of the 0-rotation drive section equipped with the guide shaft 103, and the vertical movement of the rotation drive section 105 and the lamp house section 100 is controlled by the eccentric cam 101. Determined by the shape of.

The slit 7 has an opening parallel to the tube axis of the ultra-high pressure mercury lamp 104, as shown in FIG. 1(d), and the width of the opening is, for example, wide enough to expose one-third of the center of the screen.

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, because the ultra-high-pressure mercury lamp is rotated, the optical correction plate used in exposure equipment that has a fixed light source with the tube axis of the ultra-high-pressure mercury lamp aligned horizontally with the screen could not be used in the past. In synchronization with the rotation of the high-pressure mercury lamp, a slit parallel to the tube axis of the ultra-high pressure mercury lamp rotates, and in synchronization with this rotation angle, when exposing the top and bottom of the screen, the light source part is moved to the tube axis 6 by the seishin cam 101. By moving the lamp forward toward the panel, a slit is provided in the ultra-high-pressure mercury lamp, allowing use of the optical correction plate used in optical exposure systems in which the axis of the ultra-high-pressure mercury lamp is oriented horizontally to the screen.

However, since a rotating slit is used, the amount of exposure light at the periphery of the screen is smaller than at the center of the screen, so it is necessary to use a light amount correction plate to prevent the amount of exposure light from decreasing at the center of the screen. As an example of an unused pond, the central part of the slit 7 may be set narrow as shown in FIG. 1(e).

〔Effect of the invention〕

As explained above, the present invention eliminates local differences in light intensity caused by arc tubes such as ultra-high-pressure mercury lamps using a simple light intensity correction plate by rotating the arc tube, thereby adjusting the desired size of phosphor dots. The arc tube is covered with a light-shielding sleeve having slits in the circumferential direction of the arc tube, and rotates around an axis perpendicular to the tube axis of the arc tube, and rotates parallel to the tube axis of the arc tube. By having a slit that rotates in synchronization and moving the light source position up and down in synchronization with the rotation angle, it is possible to use the optical correction plate that was previously used in exposure equipment where the arc tube was fixed. be.

[Brief explanation of drawings]

FIG. 1(a) is a sectional view showing one embodiment of the present invention, FIG. 1(b)
, (C) is an enlarged view of the light source section, (d) is a view of the slit section viewed from above, (e) is a diagram showing another embodiment, and FIGS. 2(a) and (b) are conventional exposure Figure 3 is a diagram showing the structure of the in-line color cathode ray tube, Figure 4 is an explanatory diagram showing the optical system for exposing dots corresponding to the central beam, and Figure 5 is a diagram showing the light source used in the device. Figure 6 (a) shows an example where the sizes of the phosphor dots are not aligned at the four corners of the screen.
) is a diagram showing the center of the light source in a plane perpendicular to the tube axis of a light source with a slit, and (b) is a diagram showing the center of the light source in a plane including the tube axis. 1... Light source part 2... Optical correction plate 3...
・Light level correction plate 4...Panel 5...Shadow mask 6...Tube axis 7...Slit 1
00... Lamp house part 101... Eccentric cam
102...Slide axis 103...Guide axis
104... Ultra-high pressure mercury lamp 105... Rotation drive unit
106...Motor (a) Fig. 1 (d) Fig. 1 (e) Fig. 1 (α) Fig. 2 Fig. 3 Fig. 4

Claims (1)

[Claims] (1) Exposure that uses a cylindrical arc tube as a point light source by covering it with a light-shielding sleeve with slits in the circumferential direction, and rotating the light source, which is made by filling the sleeve with a coolant around an axis perpendicular to the tube axis of the arc tube, as a point light source. An exposure apparatus characterized by having a slit that rotates in synchronization with the rotation of the arc tube parallel to the tube axis of the arc tube, and a mechanism that moves the light source position up and down in accordance with the rotation angle of the arc tube.