MXPA00006334A - Light source device, exposure device and cathode-ray tube panel - Google Patents

Abstract

To eliminate irregularity in luminance distribution of exposure light by positioning the upper surface side edge part of an open wall surface of a shading plate installed above an optical window and an optical window presser on the optical path of outgoing light or in the vicinity outside the optical path, and by arranging the optical window presser in a region defined outside a border line passing the position of the lower surface side edge part of the open wall surface of the shading plate. First, a shading plate 2 installed above an optical window presser 15 must block reflected/scattered light produced by an open wall surface 15HS of the optical window presser 15, and must pass direct light required for exposure at the same time. Then, the maximum angle of light used for the exposure out of the direct light produced in a mercury light source and emitted from an optical window 14 is referred to as a utilization angle of the light. The shading plate 2 should be installed so that the direct light emitted from the optical window 14 while having the outgoing angle exceeding the utilization angle can be blocked. The open wall surface 2HS of the shading plate 2 projects toward the center axis of the optical window 14 as compared with the open wall surface 15HS of the optical window presser 15.

Description

FUKNTE LIGHT DEVICE, EXPOSURE DEVICE, AND CATHODE RAY PIPELINE PANEL BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a light source device incorporated in an exposure apparatus for use in the manufacture of a cathode ray tube panel (hereinafter referred to as "CRT"). ). More particularly, the invention relates to a light source device capable of intercepting light, such as reflected or scattered light, which results in uneven exposure, to reduce uneven exposure, thereby achieving a high quality exhibition.

Description of the Background Art A phosphor screen on the inner surface of a panel of a cathode ray tube for use as a visual display monitor and the like, has a black matrix (hereinafter referred to as "BM") produced using Resistance exposure, and a three-color phosphor pattern produced using direct exposure. Figure 11 is a plan view (with a vertical section taken along the line I-II of an amplified part) to illustrate a structure of the phosphor screen formed in a cathode ray tube panel 70, by means of the use of an exposure device. In Figure 11, the reference numeral 701 designates a black matrix to provide a clear separation between the phosphors in order to improve the quality of an image; and 702, 703, and 704 designate the emission matches of red (R), emission of green (G), and emission of blue (B), respectively, which are formed in a pattern of strips in previously determined positions of the openings of the black matrix 701. The phosphor screen shown in Figure 11 is formed in the steps of forming the black matrix 701 by a survey method, using resistance exposure, and repeating for R, G, and B in any order, the process of applying a photosensitive phosphor material, for example for G to the inner surface of the panel in which the black matrix 701 is formed to leave strips of phosphorus, for example strips of phosphorus emitting green, in the previously determined positions of the openings of the black matrix 701 through direct exposure and development processes. Figure 12 is a cross-sectional view of an exposure apparatus for use in the manufacture of the cathode ray tube panel 70 shown in Figure 11. In Figure 12, the reference numeral 1 designates a light source device; 20 designates a light control filter; 40 designates a wedge lens; 50 designates a correction lens; and 60 designates a mask. The light emitted from the light source device 1 passes through the light control filter 20, the wedge lens 40, and the correction lens 50, onto the mask 60. The resulting shadow of the mask 60 is projected onto the internal surface of the cathode ray tube panel 70, whereby a previously determined pattern is exposed to light. Figure 13 is an amplified view of a portion indicated by the arc Cl of Figure 12, and illustrates the trajectories of the light beams passing through the mask 60 in detail. With reference to Figure 13, the light of a previously determined color or of a previously determined wavelength that is emitted from the light source device 1, impacts on the inner surface of the cathode ray tube panel 70 in a configuration in the form of fringes conforming to the openings of the mask 60. Figure 14 is a vertical sectional view of the conventional light source device 1 for use in the exposure apparatus shown in Figure 12. In Figure 14, the Reference numeral 11 designates a rod-shaped mercury light source having a light emitting region that extends linearly in the x-direction; 12 designates a light source slot for partially intercepting the light emitted from the mercury light source 11, in order to restrict an apparent light source configuration, and having a centrally located aperture to allow light to pass through. through it; and 13 designates a light source housing for containing the mercury light source 11 in its internal space through the use of O-rings 16. The internal space of the housing of the light source 13 (having an opening in its part). upper surface) in the vicinity of the light emitting region of the mercury light source 11, is filled with a refrigerant 17 to cool the mercury light source 11. The reference numeral 14 designates an optical window having a surface lower to make contact with the upper surface portion of the housing of the light source 13, having the opening, with one of the O-rings 16 therebetween, for confining the refrigerant 17 inside the internal space of the housing 13, and for direct the light from the mercury light source 11 through an upper surface of the same, towards the atmosphere. Additionally, the housing of the light source 13 includes an inlet and an outlet, both not shown, of the refrigerant 17, and discharges the refrigerant 17 through the outlet while feeding the refrigerant 17 through the inlet into the internal space. of the housing 13, at a pressure not lower than the atmospheric pressure, thus maintaining constant the temperature of the refrigerant 17 in the housing of the light source 13. Therefore, because the pressure in the internal space of the housing of the light source 13 filled with coolant 17 is always higher than atmospheric pressure, optical window 14 is maintained by an optical window fastener 15 which applies a pressure from the atmosphere to the upper surface part of the light source housing 13, with the ring-0 16 between them. The optical window fastener 15 has a centrally located opening 15H, which is circular in cross section (which is a section parallel to a plane xy), and is screwed to the housing 13 by means of a threaded groove not shown formed in the housing of the light source 13. In the conventional light source device constructed as described above, it is essential that the optical window fastener be provided on the side towards the atmosphere of the optical window. This presents a problem that will be described later. A detailed consideration of a light profile on the inner surface of the cathode ray tube panel is being exposed to the exposure light emitted from the light source device, provides a distribution as shown in Figure 15. It will be understood, from Figure 15, that the width of the pattern changes depending on the level of illuminance. In other words, when a different component of a previously determined light distribution is superimposed on the illuminance distribution of the exposure light, the distribution of the pattern width inside the panel surface shows irregularity corresponding to the superimposed component. Tracing a beam of light emitted from the mercury light source 11 of Figure 14, and passing through the interior of the refrigerant 17 and the optical window 14, to the atmosphere, provides a light path as shown in FIG. Figure 16. As illustrated in Figure 16, a light beam 91 generated in a linear light emitting region 111 of the mercury light source 11, and traveling in region 111 at an angle ^, passes to through the wall of a synthetic quartz tube 112 surrounding the light emitting region 111 at an angle 0-:, and then through the refrigerant 17 and the optical window 14 at the angles TQ and? - ^, respectively, and emerges into the atmosphere at an exit angle? . The ranges of the angles? ^, T J., T Q,? - ^ y? of the respective light beams 91 to 95 are calculated immediately. The angle ¿of the light beam 91 emitted from the light emitting region 111 is less than a maximum of ± 90 ° (See Expression (1)), because a light beam having an angular component of 0 ° at less than 90 ° it can pass through the synthetic quartz tube 112. The maximum value of the angle t9-¡of the light beam 92 in the synthetic quartz tube is + 42.70 ° (See Expression (2)), and the maximum value of the angle TQ of the light beam 93 in the refrigerant 17 is + 48.28 ° (See Expression (3)). The maximum value of the angle? ^ Of the light beam 94 in the optical window 14 is + 42.70 ° (See Expression (4)). The maximum value of the angle? of the light beam 95 in the atmosphere outside the optical window 14, which is equal to the angle -j_ in the light emitting region 111 as a result of the calculation, is less than + 90 ° (See Expression (1)). That is, the light beam 93 emitted from the mercury light source 11 at the angle of __ 48.28 ° to the maximum extends upwards to an exit angle? approximately + 90 ° in the atmosphere outside the optical window 14. or < | 0 | = | 0i | 90 ° (1) -1 0 < \ 0-j | < sin 1 [sin 0-¡max - 42.70 ° (2) n_, / where n-j_ = l is the refractive index of 1.47454 is the refractive index of synthetic quartz, y = 90 ' 0 < . | T Q | < so "48.28 ° (3) nt, where ^ 1.33974 is the refractive index of water. 0 < . | 0j_ | < sin-i, 42.70 '(4) ng where n_. = 1.47454 is the refractive index of synthetic quartz.Due to the light path in the conventional light source device as described above, the light beam 95 emerging from the optical window 14 at an exit angle of approximately 90 °, impacts on an opening wall surface 15 HS of the optical window holder 15, and in turn, the opening wall surface 15 HS serves as a secondary light source for generating the reflected or scattered light 96. The reflected or scattered light 96 is superimposed on the exposure light reaching the inner surface of the cathode ray tube panel directly from the mercury light source 11, so as to cause an irregular illuminance distribution.This irregular illuminance distribution leads to an irregular pattern width of the black matrix (BM), and to an irregular pattern width of the subsequently generated matches R, G, and B, due to the cause and effect relationship described with reference to Figure 15, which results in the lower quality of the phosphor screen.

COMPENDIUM OF THE INVENTION A first aspect of the present invention is for a light source device incorporated in an exposure apparatus for use in the manufacture of a cathode ray tube panel. In accordance with the present invention, the light source device comprises: a light source; a light source housing configured to contain the light source therein; an optical window configured to cause light from the light source to emerge into the atmosphere; an optical window fastener configured to fix the optical window to the housing of the light source; and a protection plate placed on the optical window and the optical window fastener, and having an opening wall surface extending inward beyond an aperture wall surface of the optical window fastener, to a position that overlaps the optical window, wherein a portion of the upper surface edge of the opening wall surface of the protection plate is placed in a region that includes the exterior of an optical path of the exit light emerging from the window optical towards the atmosphere at a predetermined angle, and wherein the optical window fastener is placed in a region that includes and outside a boundary line passing through a position of a lower surface edge portion of the wall surface of opening of the protection plate, and having a symmetrical line relationship with the optical path of the output light. Preferably, in accordance with a second aspect of the present invention, in the light source device of the first aspect, the upper surface edge portion of the opening wall surface of the protection plate is placed on the optical path of the exit light. Preferably, in accordance with a third aspect of the present invention, in the light source device of the first aspect, the upper surface edge portion of the opening wall surface of the protection plate is placed outside and close to the optical path of the output light. Preferably, in accordance with a fourth aspect of the present invention, in the light source device of the first aspect, a shore portion of the aperture wall surface of the optical window fastener is contacted with an upper surface of the optical window, in a position on the limit line. Preferably, in accordance with a fifth aspect of the present invention, in the light source device of the fourth aspect, the opening wall surface of the optical window fastener is a surface perpendicular to the upper surface of the optical window. Preferably, in accordance with a sixth aspect of the present invention, in the light source device of the fourth aspect, the aperture wall surface of the optical window fastener is a thinned surface extending along the boundary line . Preferably, in accordance with a seventh aspect of the present invention, in the light source device of the first aspect, the previously determined angle is a useful angle of light defined as a maximum angle of direct light emerging from the optical window towards the atmosphere, and that is used for exposure. According to an eighth aspect of the present invention, an exposure apparatus comprises the light source device as mentioned in the first aspect. According to a ninth aspect of the present invention, a cathode ray tube panel comprises a phosphor screen made using the exposure apparatus as mentioned in the eighth aspect. A tenth aspect of the present invention is intended for a light source device incorporated in an exposure apparatus for use in the manufacture of a cathode ray tube panel. In accordance with the present invention, the light source device comprises: a light source; a light source housing configured to contain the light source therein; an optical window configured to cause light to emerge from the light source into the atmosphere; and an optical window fastener configured to fix the optical window to the light source housing, and having an aperture, wherein an aperture wall surface of the optical window fastener has a first edge portion in contact with an aperture surface. the optical window, and a second edge portion on the side opposite the first edge portion, and the second edge portion is placed in a region that includes and outside an optical path of the exit light emerging from the window optical to the atmosphere at a predetermined angle, and wherein the optical window fastener is placed in a region that includes and outside a boundary line that passes through the second edge portion, and that has a symmetrical line relationship with the optical path of the output light. Preferably, in accordance with a eleventh aspect of the present invention, in the light source device of the tenth aspect, the second edge portion is placed on the optical path of the exit light. Preferably, in accordance with the twelfth aspect of the present invention, in the light source device of the tenth aspect, the second edge portion is positioned outside and close to the optical path of the exit light. Preferably, in accordance with a thirteenth aspect of the present invention, in the light source device of the tenth aspect, the aperture wall surface of the optical window fastener is a thinned surface extending along the line limit. Preferably, in accordance with a fourteenth aspect of the present invention, in the light source device of the tenth aspect, the previously determined angle is a useful angle of the light defined as a maximum angle of direct light emerging from the optical window towards the atmosphere, and to be used for the exhibition. According to a fifteenth aspect of the present invention, an exposure apparatus comprises the light source device as mentioned in the tenth aspect. According to a sixteenth aspect of the present invention, a cathode ray tube panel comprises a phosphor screen made using the exposure apparatus mentioned in the fifteenth aspect. According to the first, the eighth, and the ninth aspect of the present invention, in the light source device for the cathode ray tube exposure apparatus, the protective plate of a size determined by a predetermined optical calculation, it is placed outside the optical window, and the optical window holder is disposed in a position determined by a predetermined optical calculation, in such a way that the reflected or scattered light from the opening wall surface of the optical window holder is prevented to reach an internal surface of the cathode ray tube panel. This eliminates the irregularity of an illuminance distribution of exposure light, to eliminate the irregularity of a pattern width of a black matrix and the like, thereby producing the effect of improving the quality of the phosphor screen of the cathode ray tube. . According to the tenth, fifteenth, and sixteenth aspects of the present invention, the optical window fastener has a defined configuration based on a previously determined optical calculation, to prevent the reflected or scattered light from the optical window fastener to reach an internal surface of the cathode ray tube panel. This has the effect of improving the quality of the phosphor screen formed on the inner surface of the cathode ray tube, in a manner similar to the aforementioned effect. Therefore, it is an object of the present invention to overcome a problem with a conventional light source device for an apparatus for exposing an internal surface of a cathode ray tube panel, i.e. to suppress the irregularity of an illuminance distribution of light of exposure resulting from reflected or scattered light from an aperture wall surface of an optical window fastener, to eliminate irregularity of the pattern widths of a black matrix and from the phosphors, thus improving the quality of a screen of phosphorus. These and other objects, features, appearance, and windows of the present invention will become clearer from the following detailed description of the present invention, to be taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a vertical sectional view of a structure of a light source device in accordance with a first preferred embodiment of the present invention. Figure 2 is a vertical sectional view of a basic structure of a protective plate and an optical window fastener in the light source device in accordance with the first preferred embodiment of the present invention. Figure 3 shows the definition of a useful angle for use in the description of the present invention. Figure 4 is a vertical sectional view to illustrate a function to be used in the design of the protective plate and the optical window fastener in the light source device in accordance with the present invention. Figure 5 schematically shows a range of scattered light angle. Figure 6 is a vertical sectional view of a basic structure of the protective plate and the optical window fastener in the light source device in accordance with a modification of the first preferred embodiment of the present invention. Figure 7 is a vertical sectional view of a basic structure of the protective plate and the optical window fastener in the light source device in accordance with another modification of the first preferred embodiment of the present invention. Figure 8 is a vertical sectional view of a structure of the light source device in accordance with a second preferred embodiment of the present invention. Figure 9 is a vertical sectional view showing the placement of the optical window fastener in the light source device in accordance with the second preferred embodiment of the present invention. Figure 10 is a vertical sectional view showing the positioning of the optical window fastener in the light source device in accordance with a modification of the second preferred embodiment of the present invention. Figure 11 schematically illustrates a structure of a cathode ray tube panel.

Figure 12 illustrates schematically a basic structure of an exposure apparatus. Figure 13 schematically illustrates a three-color exposure method. Figure 14 is a vertical sectional view of a conventional light source device. Figure 15 illustrates the dependence of the width of an exposure pattern on the illuminance. Figure 16 illustrates a problem with a conventional light source device.

DESCRIPTION OF THE PREFERRED MODALITIES (First Preferred Modality) A light source device according to a first preferred embodiment of the present invention, which is incorporated in an exposure apparatus for the manufacture of a cathode ray tube panel, is such that a protection plate is provided on an optical window fastener, and that the optical window fastener and the protection plate are placed in a determined positional relationship based on a predetermined equation. Accordingly, the light source device is improved to prevent reflected or scattered light from an aperture wall surface of the optical window fastener to reach the inner surface of the cathode ray tube panel. The characteristics of the light source device will now be described in accordance with the first preferred embodiment of the present invention, with reference to the drawings. The exposure apparatus itself, wherein the light source device that will be described below is incorporated, is of a construction similar to the conventional exposure apparatus shown in Figure 12. Figure 1 is a vertical sectional view showing schematically the internal structure of a light source device 1 in accordance with the first preferred embodiment. The light source device 1 shown in Figure 1 comprises a light source housing 13, a mercury light source 11, rings-0 16, a light source slot 12, and an optical window 14, which are of a construction identical to those of the conventional light source device shown in Figure 14. In the light source device 1, the internal space of the light source housing 13, wherein the mercury light source 11 is disposed, and having an aperture sealed with the lower surface of the optical window 14, with one of the rings-0 16 between them, is also filled with a refrigerant 17. The mercury light source 11 and the light source slot 12 can be defined together generically as a "light source". The characteristics of the light source device 1 are only an optical window fastener 15 and a protective plate 2 disposed thereon. The structure and configuration of the optical window fastener 15 and the protective plate 2 are described hereinafter. The optical window fastener 15 has a centrally located opening 15H which, for example, is of a circular cross section. The "cross-section" used herein means a section of the opening 15H taken along a plane perpendicular to the plane of Figure 1, and parallel to an upper surface of the optical window 14 (or a plane parallel to a xy plane). The circular shape of the opening 15H in cross section is used here for convenience, to force the optical window 14 against the light source housing 13, with the ring-0 16 between them. The optical window fastener 15 has an outer end portion 15E bent into an L-shaped configuration, and secured to an upper portion of the light source housing 13 by screws, not shown, in a conventional manner. The protection plate 2 has a rectangular opening 2H located centrally therein, and having a width or dimension measured in a lateral direction (direction x) that is smaller than the diameter of the opening 15H (in which case, a longitudinal direction is the direction and perpendicular to the plane of Figure 1). Part of an L-shaped external end portion 2E of the protective plate 2 is secured by screws, not shown, to the outer surface of the end portion 15E of the fastener 15, such that the center of the plate 2 it is placed by a predetermined amount above the upper surface of the optical window fastener 15 (as seen in the z-direction). Figure 2 is an enlarged vertical sectional view of Figure 1, showing the configuration of the optical window fastener 15 and the protective plate 2, one relative to the other. The positional relationship between the protective plate 2 and the optical window fastener 15 shown in FIG.

Figure 2, is determined from the following point of view. The protective plate 2 disposed on the optical window fastener 15 must intercept reflected or scattered light from an aperture wall surface 15HS, of the optical window fastener 15, and allow light to pass through it (direct light). required for the exhibition. As shown in Figure 3, the maximum angle of direct light to be used in the exposure that is emitted from the mercury light source 11, and emerging from the optical window 14, is referred to as a useful angle (angle previously determined) 0e of light (and in accordance with the same, a region defined by the exit angle falling within the useful angle 0e, is a region where it is not desired to enter the reflected or scattered light of the wall surface of the 15HS aperture of the optical window holder 15, and it must reach the light for exposure of the light source). Then, the protective plate 2 should be placed in such a way as to intercept the direct light emerging from the optical window 14 at an exit angle that exceeds the useful angle 0e. An optical path Zr (x) of light emerging from the optical window 14 to the atmosphere at the useful angle? E is calculated to define a region where the protective plate 2 is to be placed, that is, a region outside the Useful angle 0e of direct light. With reference to Figure 4, the optical path Zr (x) is calculated as: Zr (x) = (xsv) cot0e (x > s + v) t - sin 0e v = (5) nq2 - sin2 c where t is the thickness of the optical window 14, n-_ is the refractive index of the material of the optical window 14, and s is a wide half of the slot opening of the light source 12. As described above, in the light source device 1, an opening wall surface 2HS of the protective plate 2 extends towards a central axis of the optical window 14 (or inward) beyond the opening wall surface 15HS of the window fastener optical 15, to a position that overlaps the optical window 14, and an upper surface edge portion 2UE of the opening wall surface 2HS is placed over the optical path Zr (x) of the exit light or direct light which emerges from the optical window 14 towards the atmosphere at the useful angle 0e. Accordingly, the protective plate 2 is placed in a position that satisfies: Xu = u / cot (0e) + v + s (6) where Xu is a wide medium of the opening 2H as it is in the x direction (lateral direction ), and u is the height of the upper surface edge portion 2UE, measured from the upper surface of the optical window 14. The optical window fastener 15 is manufactured and placed in a region outside of a boundary line passing through. the position of a lower surface edge portion 2LE of the opening wall surface 2HS of the protective plate 2, and having a symmetrical line relationship with the optical path Zr (x), i.e., a boundary line or place Zh (x) given by Expression (7) (including this region the boundary line Zh (x), and extending away from the z-axis), and also in a region outside the optical path or boundary line Zr (x) by Expression 5). Zh (x) = - (l / tan (0e)) (x - Xu) + u (x >; Xu) Zh (x) = - (l / tan (0e)) (x + Xu) + u (x < -Xu) (7) In the case shown in Figures 1 and 2, the opening wall surface 15HS of the optical window fastener 15, is perpendicular to the upper surface of the optical window 14, and a first edge portion of the wall surface 15HS, to make contact with the upper surface of the optical window 14, is set to a position on the boundary line Zh (x) (that is, a position that satisfies Zh (x) = 0). Because the protective plate 2 and the optical window fastener 15 are manufactured and configured in the manner described above, the light scattered from the opening wall surface 15HS of the optical window fastener 15 at an angle that is within the angle useful 0e, it is intercepted by the protective plate 2 which is superimposed on the wall surface 15HS. On the other hand, most of the light scattered at an angle exceeding the useful angle? E is intercepted in a similar manner by the protective plate 2, but part of the light scattered at an angle exceeding the useful angle 0e passes through the region surrounded by the optical path Zr (x) near the housing of the light source. However, as shown schematically in Figure 5, the light source device 1 and the internal surface (or the phosphor screen) of the cathode ray tube panel 70 are separated by a sufficient distance (eg, approximately 300 millimeters) one from the other, and the width (for example of approximately 10 millimeters) of the opening 2H of the protective plate 2 limits the angle range of the scattered light passing through the opening 2H of the protective plate 2 Accordingly, the scattered light passing through the aperture 2H merely passes through part of the region surrounded by the optical path Zr (x), before reaching the inner surface of the cathode ray tube panel 70, and does not reach the internal surface of the cathode ray tube panel 70. The useful angle 0e is from plus 0 ° to less than 90 °, and can be set to any value. With reference to Figure 2, the useful angle 0e is set to 45 °, the thickness t of the optical window 14 is set to 2 millimeters, and the wide half s of the aperture of the light source slot 12 is set to 4 mm. If the upper surface edge portion 2UE or the upper surface of the opening 2H of the protective plate 2 is placed at a position 7 millimeters above the interface between the optical window 14 and the optical window fastener 15 (a position that satisfies z = u = 7 millimeters in Figure 2), then Xu = 12.1 millimeters is obtained (where the refractive index n-, of the synthetic quartz is equal to 1.47454 in the present). Then, the boundary line Zh (x) is: Zh (x) = - (x-Xu) + u = -x + 19.1 (12.1 < .x < 19.1) Zh (x) = (x + Xu) + u = x + 19.1 (-19.1 < x < -12.1) (8) where Xu = 12.1 (millimeters), yu = 7 (millimeters).

The manufacture and placement of the protective plate 2 and the optical window fastener 15 in the aforementioned manner, allow only direct light emitted from the mercury light source 11, and emerging from the optical window 14 at an angle that is within the useful angle 0e, passes through the protective plate 2, to reach the inner surface of the cathode ray tube panel, while intercepting the direct light emerging from the optical window 14 at other angles, as illustrated in Figures 2 and 5. Additionally, if direct light emerging at an angle exceeding the usable angle 0e impacts the aperture wall surface 15HS of the optical window fastener 15 to generate the reflected or scattered light, the reflected light or dispersed does not reach the inner surface of the cathode ray tube panel through the region surrounded by the optical path Zr (x).

(Modifications of the First Preferred Modality) (1) In the first preferred embodiment (shown in Figure 2), the protective plate 2 is positioned in such a manner that the upper surface edge portion 2UE of the opening wall surface 2HS of the protective plate 2 is placed on the optical path Zr (x). Alternatively, the dimension of the opening (measured in the x-direction) of the protective plate 2 can be changed, such that the upper surface edge portion 2UE of the opening wall surface 2HS of the protective plate 2 is placed outside and near the optical path Zr (x). An example of this placement is illustrated in Figure 6. With reference to Figure 6, the width means Xu of the opening 2H of the protective plate 2 is larger than that of the first preferred embodiment shown in Figure 2. The fastener of The optical window 15 of Figure 6 is of a shape and configuration similar to that of Figure 2. For example, when the width means Xu of the opening 2H of the protective plate 2 is set to 13 millimeters, the function expression Zh ( x) is: Zh (x) = -x +20 (13 <x <20 (mm)) Zh (x) = x +20 (-20 <x < -13 (mm)) ( 9) Accordingly, the optical window fastener 15 of Figure 6 must be fabricated and positioned to be in the region outside (and including) the boundary line given by Expression (9). The reason for, and the advantage of, the establishment of the wide medium Xu, as illustrated in Figure 6, are as follows: The protective plate 2 manufactured to completely intercept (direct) light emerging at a different angle from the useful angle , as in the first preferred embodiment (shown in Figure 2), will also intercept the light required for the exposure if the protective plate 2 deviates from its proper position. In consideration of the presentation of this deviation, it is desired to produce the actual protective plate 2 having the opening 2H of a slightly larger width. This modification (1) shows an application having the protective plate 2 produced based on these considerations. In this case, light scattered from the aperture wall surface 15HS is also prevented from entering the region surrounded by the optical path Zr (x), and reaching the internal surface of the cathode ray tube plate. (2) The opening wall surface 15HS of the optical window fastener 15 can be of any configuration, as long as the fastener 15 is in the region outside the optical path Zr (x), and also in the region outside the line limit expressed by the function expression Zh (x), thus producing similar functions and effects. Figure 7 shows the optical window fastener 15 according to the modification (2) of the first preferred embodiment, used in place of the optical window fastener 15 of the first preferred embodiment shown in Figure 2. The opening wall surface 15HS of the fastener 15 is thinned along the boundary line Zh (x). Additionally, the light source device of Figure 6 may comprise the optical window fastener 15 of a thinned configuration shown in Figure 7 in place of the optical window fastener 15 of Figure 6.

(Second Preferred Modality) Although the protective plate and the optical window fastener are produced separately in the first preferred embodiment and in modifications (1) and (2) thereof, the protective plate and the optical window fastener can be produced. integrate together in a one-piece configuration, thus producing similar functions and effects. A second preferred embodiment of the present invention uses this consideration. Figure 8 is a vertical sectional view schematically showing an internal structure of the light source device 1 in accordance with the second preferred embodiment. Figure 9 is an enlarged vertical sectional view of the optical window 14 and the opening 15H of the optical window fastener 15 shown in Figure 8, and illustrates the positioning of the fastener 15. From Figures 8 and 9, it will be possible to see that the optical window fastener 15 according to the second preferred embodiment corresponds to a one-piece optical window fastener, where the protective plate 2 and the optical window fastener 15 shown in Figures 1 and 2 are integrated together. More specifically, the aperture wall surface 15HS of the optical window fastener 15 is thinned along the boundary line given by the function expression Zh (x) described with respect to the first preferred embodiment, and a second edge portion E2 opposite the first edge portion El, wherein the wall surface 15HS and the upper surface of the optical window 14 make contact with each other, is placed on the path optical crystal Zr (x) described with respect to the first preferred embodiment. Accordingly, only direct light emerging from the upper surface of the optical window 14 into the atmosphere at an angle that is within the useful angle 0e, can contribute to the exposure. Additionally, direct light having an exit angle greater than the useful angle 0e, and reflected or scattered from the opening wall surface 15HS, is prevented from reaching the inner surface of the cathode ray tube panel through the region surrounded by the optical path Zr (x), and in accordance with the above, is prevented from overlapping the exposure light. Moreover, the second preferred embodiment eliminates the need to manufacture and align the protective plate as has been done in the first preferred embodiment, to provide a window in reducing the number of parts.

(Modifications of the Second Preferred Modality) (1) The protective plate 2 and the optical window fastener 15 can be integrated in a one-piece configuration also when the opening wall surface 2HS of the protective plate 2 is slightly separated towards outside from the boundary line indicated by the optical path Zr (x), in a manner described with respect to the modification (1) of the first preferred embodiment. Figure 10 shows this one-piece configuration in this case. The light source device of Figure 10 according to the modification (1) of the second preferred embodiment also produces functions and effects similar to those of the light source device 1 shown in Figure 6. (2) Although the 15HS opening wall surface of the optical window fastener 15 is of a thinned configuration in the second preferred embodiment, and modification (1) thereof, the opening wall surface 15HS of the optical window fastener 15 can be of any size. configuration, with the understanding that the opening wall surface 15HS does not enter a region within the boundary line given by the function expression Zh (x). The requirements that must be satisfied are that the second edge portion E2 of the opening wall surface 15HS is placed either on the optical path Zr (x), or outside and near the optical path Zr (x), and that the optical window fastener 15 is placed in a region that includes and outside the boundary line given by the function expression Zh (x), which is in a symmetrical line relationship with the optical path Zr (x) (Additional Modifications) Although the mercury lamp 11 extending linearly in the x-direction is used as the light source in the first and second preferred embodiments, and in the modifications thereto, a mercury lamp which is extend linearly in the direction and perpendicular to the x direction, or a lamp of any cross section configuration, such as the light source in place. Depending on the types of phosphorus, you can use a lamp that emits light that has other wavelengths instead of the mercury lamp. The present invention can be applied to a light source device employing these different lamps, to provide the light source device that produces effects similar to those of the first and second preferred embodiments. Although the invention has been described in detail, the foregoing description is in all respects illustrative and not restrictive. It is understood that numerous other modifications and variations can be devised without departing from the scope of the invention.

Claims (16)

1. A light source device incorporated in an exposure apparatus, for use in the manufacture of a cathode ray tube panel, said light source device comprising: a light source; a light source housing configured to contain the light source therein; an optical window configured to cause light from the light source to emerge into the atmosphere; an optical window fastener configured to fix the optical window to the housing of the light source; and a protective plate placed on the optical window and the optical window fastener, and having an opening wall surface extending inwardly beyond an aperture wall surface of the optical window fastener, to a position that is overlays the optical window, wherein a portion of the upper surface edge of the opening wall surface of the protective plate is placed in a region that includes and outside an optical path of the exit light emerging from the optical window towards the atmosphere at a predetermined angle, and wherein the optical window fastener is placed in a region that includes and outside a boundary line passing through a position of a lower surface edge portion of the opening wall surface of the protective plate, and having a symmetrical line relationship with the optical path of the output light.

The light source device according to claim 1, wherein the upper surface edge portion of the opening wall surface of the protective plate is placed on the optical path of the exit light.

The light source device according to claim 1, wherein the upper surface edge portion of the opening wall surface of the protective plate is positioned outside and close to the optical path of the exit light.

The light source device according to claim 1, wherein a edge portion of the aperture wall surface of the optical window fastener in contact with an upper surface of the optical window is set to a position on the line limit.

5. The light source device according to claim 4, wherein the opening wall surface of the optical window fastener is a surface perpendicular to the upper surface of the optical window.

The light source device according to claim 4, wherein the aperture wall surface of the optical window fastener is a thinned surface extending along the boundary line.

The light source device according to claim 1, wherein the previously determined angle is a useful angle of light defined as a maximum angle of direct light emerging from the optical window towards the atmosphere, and to be used for the exposition.

8. An exposure apparatus, which comprises: the light source device as described in the claim.

9. A cathode ray tube panel, comprising: a phosphor screen made using the exposure apparatus as described in claim 8.

10. A light source device incorporated in an exposure apparatus for use in the making a cathode ray tube panel, said light source device comprising: a light source; a light source housing configured to contain the light source therein; an optical window configured to cause light from the light source to emerge into the atmosphere; and an optical window fastener configured to fix the optical window to the housing of the light source, and having an aperture, wherein an aperture wall surface of the optical window fastener has a first edge portion in contact with a surface of the optical window, and a second edge portion on the side opposite the first edge portion, and the second edge portion is placed in a region that includes and outside an optical path of the exit light emerging from the optical window toward the atmosphere at a predetermined angle, and wherein the optical window fastener is placed in a region that includes and outside a boundary line that passes through the second edge portion, and that has a symmetric line relationship with the path optics of the exit light.

The light source device according to claim 10, wherein the second edge portion is placed on the optical path of the exit light.

The light source device according to claim 10, wherein the second edge portion is positioned outside and close to the optical path of the exit light.

The light source device according to claim 10, wherein the aperture wall surface of the optical window fastener is a thinned surface extending along the boundary line.

The light source device according to claim 10, wherein the previously determined angle is a useful angle of light defined as a maximum angle of direct light emerging from the optical window towards the atmosphere, and to be used for the exposition.

15. An exposure apparatus, comprising: the light source device as described in claim 10.

16. A cathode ray tube panel, which comprises: a phosphor screen manufactured using the exposure apparatus as is described in claim 15.