JPH0731979B2 - Exposure equipment - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to an exposure apparatus used for forming a fluorescent screen of a color cathode ray tube.

[Technical background of the invention and its problems]

The color cathode ray tube has a phosphor screen formed of a three-color phosphor on the inner surface of the panel, facing the shadow mask arranged inside the front surface of the envelope. This phosphor screen is made by applying a slurry prepared by mixing a phosphor into a photosensitive resin solution on the inner surface of the panel and then irradiating the applied film with light through a shadow mask. An exposure device is used.

This exposure apparatus includes a light source arranged at a predetermined position with respect to a panel positioned on a support base, a correction lens for correcting an optical path of light entering the panel through a through hole of a shadow mask, an inner surface of the panel. Various structures having a shutter or the like for controlling light incident on are used.

Using this exposure apparatus, as a shadow mask, a plurality of slit-shaped through holes are arranged in the minor axis direction of the shadow mask via narrow bridges, and the above-mentioned transparent mask is formed on the inner surface of the panel in the minor axis direction. When forming a phosphor screen in which stripe-shaped three-color phosphors are arranged corresponding to the hole arrangement, usually, the light source moves a point light source in the longitudinal direction of the stripe-shaped phosphor or the stripe-shaped phosphor. A long tubular light source that is long in the longitudinal direction of the phosphor is used.

However, even if such a light source is used, it is difficult to obtain a uniform illuminance distribution in the short axis direction of the panel due to the bridge of the shadow mask, and the formed stripe is likely to have a constriction corresponding to the bridge. .

In order to solve this, Japanese Patent Publication No. 58-56939 discloses
A technique is disclosed in which a slit light shielding plate is moved along a tubular long light source in the longitudinal direction by a certain distance. According to this exposure method, the amount of constriction can be reduced over the entire surface of the panel, but the distance from the light source to the inner surface of the panel is different between the center part of the panel and the peripheral part because the moving distance of the slit light shielding plate is constant. However, it is difficult to make a stripe-shaped phosphor having no constriction over the entire phosphor screen, and it is impossible to expect a significant improvement in screen quality.

[Object of the Invention]

The present invention configures an exposure apparatus that can easily form a stripe-shaped phosphor having no constriction corresponding to the bridge on the entire inner surface of the panel by using a shadow mask in which a bridge is provided between slit-shaped through holes. Especially.

[Outline of Invention]

A long light source that irradiates light through a shadow mask to a photosensitive resin-containing film formed on the inner surface of the panel, and a slit axis that is orthogonal to the longitudinal direction of this long light source, and with respect to the width of the slit axis direction peripheral portion. A slit having a wide central portion is formed, and a light-shielding body is disposed so as to surround the long light source and is adjacent to the shadow mask, and the width of the slit of the light-shielding body in the long light source longitudinal direction is set. , P is the distance from the long light source to the inner surface of the panel, Q is the distance between the inner surface of the panel and the shadow mask, and the spot vertical pitch of the light of the long light source obtained on the inner surface of the panel through the shadow mask. As Dp, the length L of the long light source in the longitudinal direction is on the inner surface of the panel. By forming so as to have a size represented by
Even if a shadow mask having a bridge between slit-shaped through holes is used, stripe-shaped phosphors having no constriction can be easily formed over the entire inner surface of the panel.

Example of Invention

Hereinafter, the present invention will be described based on embodiments with reference to the drawings.

FIG. 2 shows the structure of an exposure apparatus that forms a fluorescent screen made of striped fluorescent material on the inner surface of the panel using a shadow mask in which a plurality of slit-shaped through holes are arranged in the minor axis direction of the shadow mask via bridges. Show. This exposure apparatus is a tubular long light source consisting of an ultra-high pressure mercury lamp that irradiates a photosensitive resin-containing film formed on the inner surface of a panel (2) supported by a support base (1) through a shadow mask (3). Have (4). This tubular long light source (4) has a shadow mask (3) in the longitudinal direction.
Alternatively, they are arranged in the same direction as the minor axis of the panel (2). In the middle of the tubular long light source (4) and the shadow mask (3), a correction lens (5) for correcting the path of light emitted from the long tubular light source (2) incident on the inner surface of the panel (2), etc. And the panel (2) near the support (1).
A light transmission part (6) is formed so that the inner surface is partially illuminated, and a shutter (7) reciprocally moved in the direction of arrow (A), that is, the minor axis direction of the panel (2) by a driving device (not shown) is provided. It is provided. In synchronization with the movement of this shutter (7), the tubular long light source (4) is arranged so as to be parallel to the inner surface irradiation part of the panel (2).
Is attached to a rotary drive device and is configured to reciprocate as shown by an arrow (B). However, the tubular long light source (4) is covered with a coaxial transparent cooling tube (8), and on the surface of the cooling tube (8) on the shadow mask (3) side, the inner tubular long light source (4) is provided. A light shield (9) having a slit described later is provided so as to cover the.

In Fig. 2 (A), (10) is a bridge (11).
The stripe-shaped phosphors formed on the inner surface of the panel (2) are shown corresponding to the slit-shaped through holes (12) of the shadow mask (3) arranged in plural via.

Next, the light shield (9) in which the slit is formed will be described.

Using the shadow mask (3) in which a plurality of slit-shaped through holes (12) are arranged through the bridge (11) in the minor axis direction of the shadow mask (3), a stripe without constriction on the inner surface of the panel (2) In order to form the fluorescent substance (10), as shown in FIG. 3, the distance from the long tubular light source (4) to the inner surface of the panel (2) is P, the inner surface of the panel (2) and the shadow mask (3). Is Q, and the pitch of the spots of the tubular long light source (4) obtained on the inner surface of the panel (2) through the shadow mask (3) in the panel (2) in the minor axis direction, that is, the vertical pitch is Dp. When A light source of length L represented by It has been found that a good result can be obtained with a length L represented by.

However, the distance P from the tubular long light source (4) to the inner surface of the panel (2) and the distance Q between the inner surface of the panel (2) and the shadow mask (3) are as shown in the table below for an example of a 17-inch tube. , The panel (2) is different between the central part and the peripheral part.

Therefore, in order to obtain a light source satisfying the expression (2), it is necessary to change the length L of the light source in accordance with the light irradiation position on the inner surface of the panel (2).

In order to obtain such a light source, in the above exposure apparatus, exposure is performed while moving the shutter (7) having the light transmitting portion (6) in the minor axis direction of the panel (2) (longitudinal direction of the tubular long light source (4)). Therefore, in synchronization with the movement of this shutter (7), the tubular long light source (4)
A slit having a slit axis in a direction orthogonal to the longitudinal direction of the (long axis direction of the panel (2)) was formed, and the width of the slit in the longitudinal direction of the tubular long light source (4) was changed. A light shield (9) having such slits is shown in FIG.
The light shield (9) is arranged along the cooling pipe (8) so that parts thereof overlap with each other, and is driven by a driving device (not shown) so as to have a tubular length as shown by arrows (C ₁ ) and (C ₂ ). A pair of light-shielding members (14a), (14) which are driven so as to freely come in contact with and separate from the light source (4) in the longitudinal direction.
b), and a slit (15) is formed in its weight portion. The width S of the slit (15) is such that the light source length L determined by the equation (2) is obtained at each point on the long axis of the panel (2) based on the values of P and Q at that point. In a generally ordinary color cathode ray tube, the width of the center of the slit (15) is wider than the width of the peripheral portion on the slit axis orthogonal to the longitudinal direction of the tubular long light source (4),
Moreover, since the values of P and Q at each point on the long axis of the panel (2) are symmetrical with respect to the center of the panel (2), they are symmetrical with respect to the axis orthogonal to the slit axis. In the illustrated example, as shown in FIG. 1 (B), the planar shape has a diagonal axis that coincides with the longitudinal direction of the long tubular light source (4), and a pair of opposing electrodes are provided in the slit axial direction with the diagonal axis sandwiched therebetween. It has a hexagonal shape with side edges, and as shown in (A), the front shape (the shape when viewed from the side) is formed into an inverted trapezoidal shape. The width of the slit (15) formed in this way is adjusted so that when exposing the peripheral portion of the panel (2) in the short axis direction, the light source length is adapted to the exposure of the peripheral portion.
A pair of light blocking members (14a) and (14) that move in synchronization with the movement of (7).
Adjusted by moving b). In this case, the pair of light blocking members (14a) and (14b) do not move the center position of the slit (15) by moving in and out by an equal amount.

As described above, the light shielding body (9) is provided so as to surround the tubular long light source (4) and in close proximity thereto, and the light shielding body (9) is moved in the longitudinal direction of the tubular long light source (4) so as to be movable in and out of contact with each other. A slit (15) of variable width, which is composed of a light-shielding member, and whose weight portion has a light source length L adapted to each point on the inner surface of the panel (2)
If a shadow mask (3) having a plurality of slit-shaped through holes (12) arranged through a bridge (11) is used, a stripe-shaped phosphor without constriction can be formed on the entire inner surface of the panel (2). Can be formed. Such an exposure apparatus can be applied to an ordinary TV color CRT to form a required fluorescent screen, but compared to an ordinary color CRT, a color CRT for a display having a smaller shadow mask through-hole pitch. Can be applied to, and the screen quality can be significantly improved.

Next, another embodiment will be described.

In the above-mentioned embodiment, the light shield is composed of a pair of light shield members which can be freely contacted and separated in the longitudinal direction of the tubular light-emitting source, and the variable width slit is provided in the weight portion thereof, but as shown in FIG. Light-shielding body (9) consisting of one light-shielding member on which (15) is formed
May be fixedly arranged on the cooling pipe (8). in this case,
The slit width is based on the values of P and Q at each point on the long axis of the panel as described in the above embodiment (2).
The light source length L determined by the formula may be used, but it may be set to an intermediate value between each point on the panel long axis and each point on the panel short axis direction peripheral portion corresponding to each point. It ’s even better. Even an exposure apparatus including such a light shield (9) can be sufficiently used for forming a fluorescent screen of a normal color CRT that does not require much accuracy.

In addition, in the above-mentioned embodiment, the exposure apparatus which moves the shutter having the light transmitting portion formed to perform partial exposure has been described.
The present invention can also be applied to an exposure apparatus that simultaneously exposes the entire inner surface of the panel. When a meniscus lens is used in the exposure apparatus to correct the landing of the electron beam on the fluorescent screen, the length of the light source is 1.1 times the length L of the light source when the meniscus lens is not experimentally used due to the lens action. The light source is required, and the slit width of the light shield may be determined so that the light source length L of the following formula (3) can be obtained instead of the above formula (2) on the long axis of the panel inner surface or on the entire surface.

[Effects of the Invention] A light shield having a slit having a slit axis in a direction orthogonal to the longitudinal direction of the tubular long light source is provided so as to surround the tubular long light source, and the slit width is set at each point on the inner surface of the panel. Where P is the distance from the tubular long light source to the panel inner surface, Q is the distance between the panel inner surface and the shadow mask, and Dp is the spot vertical pitch of the light of the tubular long light source obtained on the panel inner surface through the shadow mask. When the meniscus lens is used so that the light source length L is expressed by Since the length L of the light source is represented by, even if a shadow mask in which a plurality of slit-shaped through holes are arranged via bridges is used, a desired stripe-shaped phosphor without constriction can be easily formed. be able to.

[Brief description of drawings]

1 (A) to 1 (C) are a front view, a plan view, and a sectional view taken along the line I-I in FIG. FIGS. 2 (A) to 2 (C) are plan views showing the configuration of an exposure apparatus according to an embodiment of the present invention, and a sectional view taken along the line HH in FIG. FIG. 3 is a diagram for explaining the relationship between the light source length and the distance from the tubular long light source to the panel inner surface, the distance between the panel inner surface and the shadow mask, the light spot vertical pitch on the panel inner surface, and FIG. FIGS. 9A and 9B are a front view and a plan view, respectively, showing a light-shielding body of another embodiment partially cut away. (2) …… Panel, (3) …… Shadow mask (4) …… Tubular long light source, (6) …… Light transmitting part (7) …… Shutter, (9) …… Shadow (14a), ( 14b) …… Shade member, (15) …… Slit

Claims (4)

[Claims] 1. A long light source for irradiating a photosensitive resin-containing film formed on an inner surface of a panel with light via a shadow mask, an optical system arranged between the long light source and the shadow mask, A slit having a slit axis orthogonal to the longitudinal direction of the long light source, and having a wider central portion with respect to the width of the peripheral portion in the direction of the slit axis is formed. And a distance between the long light source and the inner surface of the panel is P, a distance between the inner surface of the panel and the shadow mask is Q, and the inner surface of the panel is inserted through the shadow mask. Assuming that the vertical pitch of the light spot of the long light source obtained above is Dp, the length L of the long light source in the longitudinal direction becomes a size represented by L = Dp · P / Q on the inner surface of the panel. Is formed in And an exposure apparatus. 2. The optical system has a meniscus lens, and the slit is formed so that the length L of the long light source in the longitudinal direction becomes a size represented by L = 1.1 Dp · P / Q on the inner surface of the panel. The exposure apparatus according to claim 1, wherein: 3. A long light source for irradiating a photosensitive resin-containing film formed on the inner surface of the panel with light through a shadow mask, and a slit axis orthogonal to the longitudinal direction of the long light source, and the periphery of the slit axis direction. A slit having a central portion whose width is wider than the width of the portion is formed, and the light shielding body is disposed on the shadow mask side so as to surround the long light source and in close proximity, and between the light shielding body and the shadow mask. And has a light transmitting portion for transmitting light from the long light source to partially irradiate the photosensitive resin-containing film formed on the inner surface of the panel, and this light transmitting portion is provided from the long light source. A slit driven so that light is spread to the photosensitive resin-containing film, the slit has a distance P from the long light source to the panel inner surface, a distance Q between the panel inner surface and the shadow mask, The above shad Assuming that the vertical pitch of the light spots of the long light source obtained on the inner surface of the panel through the mask is Dp, the length L of the long light source in the longitudinal direction is L = Dp.P / at each position on the inner surface of the panel. An exposure apparatus that is formed to have a size represented by Q. 4. The light shield has a pair of light shield members whose slit widths are variably overlapped with each other, and a drive device which drives the light shield members so that the slit widths can be variable, and corresponds to the movement of the light transmitting portion of the shutter. The exposure apparatus according to claim 3, wherein the exposure apparatus is configured to change the slit width.