KR102166261B1 - Polarized light irradiation apparatus - Google Patents

Abstract

A polarized light irradiation device capable of obtaining good polarization axis characteristics within an irradiation range is provided.
A light source 5, a filter 20, a polarizing element 25, a polarizing element holding part 26, and a light shielding plate 30 are provided. The light source 5 emits light. The filter 20 emits ultraviolet rays by irradiating the light emitted from the light source 5. The polarizing element 25 is installed on the side opposite to the light source 5 of the filter 20, and enters ultraviolet rays to emit polarized light. The polarizing element holding part 26 holds the polarizing element 25 and has an opening 27 for transmitting the polarized light emitted from the polarizing element 25. The light shielding plate 30 is provided on the side of the polarizing element holding part 26 opposite to the light source 5, and is installed surrounding the opening 28.

Description

Polarized light irradiation device {POLARIZED LIGHT IRRADIATION APPARATUS}

An embodiment of the present invention relates to a polarized light irradiation device used for manufacturing a liquid crystal panel or the like.

The rubbing process is known as a technique for performing the alignment treatment of the alignment film in the manufacture of a liquid crystal panel, etc., but recently, as a technique instead of the rubbing process, alignment treatment is performed by irradiating the alignment film with polarized light of a predetermined wavelength. A technology called photo-alignment is attracting attention. As a polarized light irradiation device that is a device for performing this optical alignment, for example, a polarized light irradiation device in which a rod-shaped lamp as a linear light source and a wire grid polarizing element having a wire grid-shaped grid are combined has been proposed. .

In the wire grid polarizing element, the dependence of the extinction ratio of the emitted polarized light with respect to the angle of light incident on the polarizing element is smaller than that of a polarizing element using a vapor deposition film or Brewster's angle. For this reason, even with divergent light such as light emitted from a rod-shaped lamp, polarized light with a relatively good extinction ratio can be obtained over the entire region to which the light is irradiated if the incident angle is in the range of ±45°. Therefore, in such a polarized light irradiation device, the length of the rod-shaped lamp is set to the length corresponding to the width of the alignment film as the object to be processed, and when performing the alignment treatment, the alignment film is unilaterally moved with respect to the polarized light irradiation device, 1 It is possible to perform the alignment treatment of the alignment film of a large area with two rod-shaped lamps.

Japanese Unexamined Patent Publication No. 2009-265290 Japanese Laid-Open Patent Publication No. 2011-145381

Here, in such a polarized light irradiation device, it is configured to irradiate light with as much light as possible to the irradiation surface of the alignment film. Specifically, by polarizing the light from the rod-shaped lamp to the polarizing element, It suppresses irradiation loss to However, when the light from the rod-shaped lamp is polarized to the polarizing element, the polarized light transmitted through the polarizing element is diffused. In addition, on the irradiated surface to which the diffused polarized light is irradiated, the polarized light becomes wider than the area of the polarizing element. It is known that the polarization axis of the polarized light irradiated to a position wider than the area of the polarizing element is deteriorated. When light having a deteriorated polarization axis is irradiated onto an alignment film that is an object to be irradiated, the characteristics of the alignment film are deteriorated.

The present invention has been made in view of the above, and an object of the present invention is to provide a polarized light irradiation apparatus that suppresses irradiation of polarized light having a reduced polarization axis characteristic outside the irradiation range. In addition, it is a second object of the present invention to provide a polarized light irradiation device using an absorption type polarizing element.

The polarized light irradiation device of the embodiment includes a light source; filter; Polarizing device; A polarizing element holding unit; And a light shielding plate. The light source emits light. The filter emits ultraviolet rays by irradiating light emitted from a light source. The polarizing element is installed on the side opposite to the light source of the filter, and incident the ultraviolet rays to emit polarized light. The polarizing element holding portion holds the polarizing element and has an opening through which polarized light emitted from the polarizing element is transmitted. The light shielding plate is provided on the side opposite to the light source in the polarizing element holding part, and is installed around the opening. A transparent member is provided at an end portion of the light shielding plate on the opposite side to the side where the opening is located, to close the inner space of the light shielding plate. The light shielding plate is provided with supply and exhaust portions in a plurality of portions. Further, the polarized light irradiation apparatus of the embodiment includes a light source for emitting light; A first polarizing element that transmits polarized light of a polarization axis parallel to a predetermined reference direction among the light emitted from the light source; And an absorption-type polarizing device that transmits polarized light of a polarization axis parallel to a predetermined reference direction among the light transmitted through the reflective polarizing device. In addition, a filter is provided between the light source and the first polarizing element. Further, the light source is a mercury lamp or a metal halide lamp.

According to the present invention, it is possible to suppress a decrease in polarization axis characteristics outside the irradiation range. Further, according to the present invention, a polarized light irradiation device using an absorption type polarizing element can be provided.

1 is an exploded perspective view showing a configuration of a polarized light irradiation device according to a first embodiment.
FIG. 2 is a cross-sectional view taken along the dashed-dotted line AA of the polarized light irradiation device shown in FIG.
3 is an explanatory view showing a state of irradiation of light in the polarized light irradiation apparatus shown in FIG. 1.
4 is an explanatory view of a polarized light irradiation device without a light shielding plate installed.
5 is a chart showing the test results of the irradiation state of polarized light.
6 is a cross-sectional view of the polarized light irradiation device according to the second embodiment as viewed in the X-axis direction.
7 is a view viewed in the direction of an arrow BB in FIG. 6.
FIG. 8 is a view viewed in the direction of the CC arrow in FIG. 7.
9 is a modified example of the polarized light irradiation device according to the second embodiment, and is an explanatory diagram when the light shielding plate is viewed in the Y-axis direction.
FIG. 10 is a view viewed in the direction of an arrow DD in FIG. 9.
11 is a perspective view showing a schematic configuration of an ultraviolet irradiation device according to an embodiment.
12 is a diagram of an ultraviolet irradiation device according to an embodiment as viewed from the Y-axis direction.
13 is a schematic diagram showing a configuration of a first polarizing element 216 of an ultraviolet irradiation device according to an embodiment.
14 is an evaluation of the extinction ratio and the temperature of the absorption type polarizing element 30 by the presence or absence of the filter 214, the first polarizing element 216, and the absorption type polarizing element 218 in the ultraviolet irradiation apparatus according to the embodiment. It is a figure showing the result.
15 is a schematic diagram showing a modified example of the ultraviolet irradiation device according to the embodiment.
16 is a diagram showing a modified example of the ultraviolet irradiation device according to the embodiment.
17 is a diagram showing another modified example of the ultraviolet irradiation device according to the embodiment.

The polarized light irradiation apparatus 1, 40 according to the embodiment described below includes a light source 5, a filter 20, a polarizing element 25, a polarizing element holding part 26, and a light shielding plate 30, 50. do. The light source 5 emits light. The filter 20 is irradiated with light emitted from the light source 5 to emit ultraviolet rays. The polarizing element 25 is installed on the side of the filter 20 opposite to the light source 5, and enters ultraviolet rays to emit polarized light. The polarizing element holding part 26 holds the polarizing element 25 and has an opening 27 through which polarized light is transmitted. The light shielding plates 30 and 50 are provided on the side of the polarizing element holding unit 26 opposite to the light source 5, and surround the opening 27 and installed.

In addition, in the polarized light irradiation device 40 according to the embodiment described below, at an end of the light shielding plate 50 on the opposite side to the side where the opening 27 is located, a transparent block that closes the inner space of the light shielding plate 50 The glass plate 52 which is a member is provided.

In addition, in the polarized light irradiation device 40 according to the embodiment described below, the light shielding plate 50 is provided with a supply and exhaust portion 55 in a plurality of portions.

In addition, the polarized light irradiation device 210 according to the embodiment described below includes a light source 211, a first polarizing element 216, and an absorption type polarizing element 218. The light source 211 emits light. The first polarizing element 216 transmits polarized light having a polarization axis parallel to a predetermined reference direction among the light emitted from the light source 211. The absorption type polarizing element 218 transmits polarized light of a polarization axis parallel to a predetermined reference direction among the light transmitted through the first polarizing element 216.

In addition, in the polarized light irradiation apparatus 210 according to the embodiment described below, a filter 214 is provided between the light source 211 and the first polarizing element 218.

In addition, in the polarized light irradiation apparatus 210 according to the embodiment described below, the light source 211 is a mercury lamp or a metal halide lamp.

[Embodiment 1]

Next, a polarized light irradiation device according to Embodiment 1 will be described based on the drawings. 1 is an exploded perspective view showing a configuration of a polarized light irradiation device according to a first embodiment. FIG. 2 is a cross-sectional view of the polarized light irradiation device shown in FIG. 1 viewed in the X-axis direction. The polarized light irradiation device 1 shown in this figure is used, for example, for manufacturing an alignment film of a liquid crystal panel or an alignment film of a viewing angle compensation film. The reference direction of the polarization axis of ultraviolet rays irradiated onto the surface of the workpiece W, which is the object to be treated, is appropriately set according to the structure, use, or required specifications of the workpiece W. Hereinafter, the width direction of the work W is referred to as the X-axis direction, and the longitudinal direction of the work W (also referred to as the conveyance direction) is referred to as the Y-axis direction, and the Y-axis direction and The direction orthogonal to the X-axis direction is called the Z-axis direction.

The polarized light irradiation device 1 according to the first embodiment includes a light source 5 that emits light including ultraviolet rays, a reflector 10 that controls light distribution of light emitted from the light source 5, and a reflective plate 10 Regarding, the filter 20 is installed on the side of the propagation direction of the light whose light distribution is controlled by the reflector 10, and the light emitted from the light source 5 and the light whose light distribution is controlled by the reflective plate 10 are incident to emit ultraviolet rays. ), a polarizing element 25 that is installed on the emission side of the filter 20 and emits polarized light when ultraviolet rays emitted from the filter 20 are incident, and a polarizing element holding unit that holds the polarizing element 25 ( 26).

The light source 5 is a rod-shaped or linear light source. In addition, the light source 5 is, for example, a high-pressure mercury lamp in which rare gases such as mercury, argon, and xenon are enclosed in an ultraviolet-transmitting glass tube, or a metal halide in which a metal halide such as iron or iodine is additionally enclosed in the high-pressure mercury lamp. It is a tubular lamp such as a lamp, and has at least a linear light emitting portion. The length direction of the light emitting portion of the light source 5 is parallel to the X-ray direction, and the length of the light emitting portion of the light source 5 is longer than the width of the work W. The light source 5 is capable of emitting light including ultraviolet rays having a wavelength of 200 nm to 400 nm, for example, from a linear light emitting portion, and the light emitted by the light source 5 has several polarization axis components. , So-called unpolarized light.

Further, the reflecting plate 10 has a reflecting surface 11 that reflects light emitted from the light source 5 on a surface facing the light source 5. The reflective surface 11 has a shape when viewed in a direction along the axis of the light source 5 formed in a rod shape, that is, a shape when viewed in the X-ray direction, and a part of the ellipse is open. It is in one shape. The reflector 10 is installed so that the center of the lamp C, which is the axial center of the light source 5, is positioned at one of the two focal points of the ellipse of the reflective surface 11, and the other focal side is open. have. In this way, the reflective plate 10 has the reflective surface 11 in the shape of a part of an ellipse. When the light source 5 is placed at one focal position, the light emitted from the light source 5 is focused on the other. It is a so-called condensing type reflecting plate that condenses near the focal point F in FIG. 3. Further, the reflecting plate 10 is provided in a direction opening in the Z-axis direction.

The reflecting plate 10 extends parallel to the light source 5 in these shapes along the light source 5 formed in a rod shape. In addition, the reflective plate 10 is a void formed in the circumferential direction of the ellipse or in the Y-axis direction at a portion opposite to the side where the ellipse of the reflective surface 11 is opened, near the portion where the curvature of the ellipse is maximized. A portion 12 is formed. That is, the void portion 12 is formed on the side opposite to the side where the ellipse of the reflective surface 11 is opened in the Z-axis direction as viewed from the light source 5. The reflective plate 10 communicates with the spaces inside and outside the ellipse in the void portion 12. Further, the reflective plate 10 is configured as a cold mirror in which the substrate is made of glass and the reflective surface 11 is formed by a multilayer film. When the polarized light irradiation device 1 irradiates polarized light onto an object to be irradiated, the light source 5 emits light while emitting heat, but the air whose temperature has been increased by this heat flows upward, and the reflector ( It comes out to the top of 10). Thereby, the polarized light irradiation device 1 irradiates the work W with ultraviolet rays without the temperature being too high.

In addition, the filter 20 is made of a known band pass filter that transmits only a specific wavelength of light emitted from the light source 5, and among the light emitted from the light source 5, for example, a predetermined amount of 254 nm or 365 nm It is possible to control the transmission of ultraviolet rays of different wavelengths and transmission of light of other wavelengths. In addition, the filter 20 is provided with respect to the light source 5 and the reflecting plate 10 on the side where the ellipse of the reflective surface 11 is opened in the Z-axis direction. This filter 20 is surrounded by the filter frame 21 around the X-axis direction and the Y-axis direction, whereby the filter 20 is held by the filter frame 21.

Like the filter 20, the polarizing element 25 is provided with respect to the light source 5 and the reflecting plate 10 on the side where the ellipse of the reflective surface 11 is opened in the Z-axis direction. The reflecting plate 10, which is a condensing type reflecting plate, is installed to condense light on the polarizing element 25.

The polarizing element 25 is a wire grid polarizing element in which a plurality of linear electric conductors (for example, metal wires such as chromium or aluminum alloy) are arranged in parallel at equal intervals on a substrate such as quartz glass. The length direction of the electric conductor is orthogonal to the reference direction. It is preferable that the pitch of the electric conductor is 1/3 or less of the wavelength of ultraviolet rays emitted from the light source 5. The polarizing element 25 reflects or absorbs most of the ultraviolet rays of the polarization axis parallel to the length direction of the electric conductor among the ultraviolet rays emitted from the filter 20 as the light emitted from the light source 5 is incident, and the length of the electric conductor It irradiates toward the work W by passing ultraviolet rays of the polarization axis orthogonal to the direction. The polarizing element 25 is capable of extracting, as polarized light, the ultraviolet rays of the polarization axis vibrating only in the reference direction from the ultraviolet rays emitted from the filter 20 installed between the light source 5 and the polarizing element 25. Further, the polarizing element 25 is capable of extracting the light of the polarization axis vibrating only in the reference direction from the light emitted from the light source 5 and having various polarization axis components vibrating in all directions in the same manner. In addition, the light of the polarization axis vibrating only in the reference direction is generally referred to as linearly polarized light. In addition, the polarization axis is the direction of vibration of the electric and magnetic fields of light.

The polarizing element holding part 26 holds a polarizing element 25 that emits polarized light by incident ultraviolet rays, and has an opening 27 that transmits polarized light emitted from the polarizing element 25. Further, the polarizing element 25 is surrounded by the polarizing element holding portion 26 around the X-axis direction and the Y-axis direction, whereby the polarizing element 25 is held by the polarizing element holding portion 26. .

Further, in the first embodiment, in the polarizing element 25, the longitudinal direction of the electric conductor is arranged in parallel with the Y-axis direction, and the ultraviolet rays of the polarization axis parallel to the X-axis direction pass. That is, in the present embodiment (1), the reference direction is parallel to the X-axis direction.

In addition, a light shielding plate 30 is provided on the side of the polarizing element holding portion 26 facing the light source 5. The light blocking plate 30 is installed so as to surround the opening 27 of the polarizing element holding part 26. In detail, the polarizing element 25 is formed in a rectangular plate shape, and the opening 27 formed in the polarizing element holding portion 26 holding the polarizing element 25 is also the same as the polarizing element 25. , Is formed in a rectangular shape corresponding to the polarizing element 25.

The light shielding plate 30 is located on the emission side of the polarized light from the opening 27 of the polarizing element holding unit 26, and protrudes from the polarizing element holding unit 26 in a direction opposite to the direction in which the light source 5 and the like are located, Further, when viewed from the opening direction of the opening 27, it is provided surrounding the opening 27. That is, the light shielding plate 30 is formed in a substantially rectangular cylindrical shape in which the inner shape becomes a slightly larger shape than the opening 27, and so that the entire rectangular-shaped opening 27 is enclosed from all directions as viewed in the Z-axis direction. It is installed in a direction in which the axial direction becomes the Z-axis direction. For this reason, the end portion of the light shielding plate 30 facing the polarizing element holding portion 26 is opened. The light shielding plate 30 provided in this way is formed as the light shielding plate reflective surface 31 on the inner side of which, for example, an aluminum foil is provided to reflect light.

In addition, it is preferable that the light shielding plate 30 is provided within a range of 5 mm or less on all four sides of the cylinder with respect to the opening 27 of the polarizing element holding portion 26. Further, the height of the light shielding plate 30 in the Z-axis direction is preferably at least 5 mm or more with respect to the irradiation surface of the work W when irradiating the work W with the polarized light irradiation device 1.

The polarized light irradiation device 1 according to the first embodiment has the configuration as described above, and the operation thereof will be described below. 3 is an explanatory view showing a state of irradiation of light in the polarized light irradiation apparatus shown in FIG. 1. In the polarized light irradiation device 1, when performing alignment treatment on a workpiece W, which is an object to be irradiated, such as an alignment film of a liquid crystal panel or an alignment film of a viewing angle compensation film, the workpiece W is transported by a transport device (not shown). , Light including ultraviolet rays is emitted from the light source 5 while conveying the work W in the direction of the arrow Y1 parallel to the Y-axis direction.

Some of the light emitted from the light source 5 faces the direction of the filter 20 and is incident on the filter 20 (for example, L1 in FIG. 3). The filter 20 does not transmit ultraviolet rays other than ultraviolet rays, but transmits only ultraviolet rays, and only ultraviolet rays are emitted from a side opposite to the side on which the light is incident.

The ultraviolet ray emitted from the filter 20 enters the polarizing element 25 held in the polarizing element holding part 26 located on the opposite side of the side where the light source 5 of the filter 20 is located. Of the incident ultraviolet rays, the polarizing element 25 does not pass most of the ultraviolet rays of the polarization axis parallel to the length direction of the electric conductor constituting the polarizing element 25, but only the ultraviolet rays of the polarization axis perpendicular to the length direction of the electric conductor. Let it. Accordingly, the polarizing element 25 emits only ultraviolet rays vibrating in the reference direction from the side opposite to the side where the filter 20 is located. The polarized light emitted from the polarizing element 25 and composed of ultraviolet rays vibrating in the reference direction passes through the opening 27 of the polarizing element holding unit 26, and the filter 20 in the polarizing element holding unit 26 The work W is irradiated through the inner side of the light shielding plate 30 provided on the side opposite to the side where is located. In the work W, alignment treatment is performed by the polarized light composed of ultraviolet rays.

In addition, as the light emitted from the light source 5 passes through the filter 20 and the polarizing element 25 as described above, some of the polarized light emitted from the polarizing element 25 is directed toward the light shielding plate 30 ( For example, L2 in FIG. 3). That is, some of the polarized light of the polarized light emitted from the polarizing element 25 passes through the opening 27 of the polarizing element holding unit 26, and when viewed in the Z-axis direction, the opening of the polarizing element holding unit 26 ( It faces the light-shielding plate reflective surface 31 of the light-shielding plate 30 provided so as to surround 27, and contacts the light-shielding plate reflective surface 31. Thereby, the polarized light hitting the light shielding plate reflective surface 31 proceeds in a direction opposite to the direction in which the polarized light was directed before reaching the light shielding plate reflecting surface 31 in the Y-axis direction, and as a result, the light shielding plate 30 blocks light .

In this way, since the inner surface of the shading plate 30 that blocks the shading light is formed of the shading plate reflecting surface 31 that reflects light, the polarized light that reaches the shading plate reflecting surface 31 is transmitted from the shading plate reflecting surface 31. It is reflected and faces in a direction opposite to the incident direction to the light shielding plate reflective surface 31. That is, the polarized light reflected on the light-shielding plate reflective surface 31 is directed from the polarizing element holding unit 26 while facing the light-shielding plate reflective surface 31 facing the light-shielding plate reflective surface 31 that reflects the polarized light. Heading away. Thereby, the polarized light reflected from the light shielding plate reflective surface 31 is directed toward the work W and irradiated onto the work W.

In addition, some of the light emitted from the light source 5 is directed toward the reflective surface 11 of the reflective plate 10, and the light toward the reflective surface 11 is reflected by the reflective surface 11, and thus the filter 20 ) In the direction of (for example, L3 in FIG. 3). In this way, light directed in the direction of the filter 20 is irradiated to the filter 20 to emit only ultraviolet rays, and the ultraviolet rays emitted from the filter 20 are incident on the polarizing element 25.

That is, the reflective surface 11 of the reflecting plate 10 transmits light emitted from the light source 5 and hitting the reflective surface 11, in the vicinity of the polarizing element 25, the filter 20 in the polarizing element 25 It reflects so that it is condensed to the focal point F located on the side opposite to the side where is located. For this reason, after reflection on the reflective surface 11, the ultraviolet rays irradiated to the filter 20 and emitted from the filter 20 are incident on the polarizing element 25 in front of the focal point F as viewed from the filter 20. . The polarizing element 25 into which the ultraviolet rays are incident from the filter 20 emits polarized light composed of ultraviolet rays vibrating in the reference direction. The polarized light passes through the inner side of the light blocking plate 30 and is irradiated onto the work W.

In addition, by being reflected from the reflective surface 11 of the reflector 10 and passing through the filter 20 and the polarizing element 25, some of the polarized light emitted from the polarizing element 25 is focused (F). After passing through, it faces the light shielding plate 30 (for example, L4 in FIG. 3). The polarized light is directly incident on the filter 20 from the light source 5, passes through the filter 20 and the polarizing element 25, touches the light shielding plate reflective surface 31, and is reflected from the light shielding plate reflective surface 31. Like light, it is reflected from the light shielding plate reflective surface 31 and faces the direction of the work W. That is, the polarized light hitting the light shielding plate reflective surface 31 is shielded by the light shielding plate 30 with respect to the traveling direction before reaching the light shielding plate 30, and is reflected in the direction of the work W by the light shielding plate reflective surface 31 do. Thereby, the polarized light reflected from the light shielding plate reflective surface 31 is irradiated onto the work W.

In the polarized light irradiation device 1 according to the first embodiment, in order to shield part of the polarized light emitted from the polarizing element 25 from the light shielding plate 30, the polarized light is irradiated with respect to the work W so that the polarized light does not diffuse too much. I can. Fig. 4 is an explanatory diagram of a polarized light irradiation device without a light shielding plate. That is, in the case of irradiating polarized light onto the work W using the polarized light irradiation device 100 without the light blocking plate 30 installed, the direct filter 20 and the polarizing element among the light emitted from the light source 5 The polarized light emitted from the polarizing element 25 by passing through (25) is irradiated to the work W in the same manner as the polarized light irradiation device 1 according to Embodiment 1 (e.g., m1 in Fig. 4). . Comparing the trajectories of both ultraviolet rays by the presence or absence of the shading plate, in the polarized light irradiation apparatus 1 according to the first embodiment, some of the polarized light was shielded by the shading plate 30, so that the Y-axis direction of the shading plate 30 The polarized light does not proceed in the direction it was directed before reaching the light shielding plate 30 from the position at, but is reflected by the light shielding plate reflective surface 31. On the other hand, in the polarized light irradiation apparatus 100 in which the light shielding plate 30 is not provided, the polarized light is not shielded by the light shielding plate 30, so that the light shielding plate 30 in the polarized light irradiating apparatus 1 according to the first embodiment. Rather than the position where) is installed, it faces the outer direction of the light shielding plate 30 formed in a rectangular cylindrical shape.

Similarly, the polarized light emitted from the polarizing element 25 by passing through the filter 20 and the polarizing element 25 after being emitted from the light source 5 and facing the reflecting plate 10, reflected from the reflective surface 11, Silver is irradiated to the work W in the same manner as in the polarized light irradiation device 1 according to the first embodiment (for example, m2 in Fig. 4). When comparing the trajectories of both ultraviolet rays according to the presence or absence of the light shielding plate, the polarized light after reflected from the reflective surface 11 is not identically blocked by the light shielding plate 30, so that some of the polarized light is the polarized light irradiation device according to the first embodiment. Rather than the position where the light-shielding plate 30 in (1) is installed, it faces the outer direction of the light-shielding plate 30 formed in a rectangular cylindrical shape.

That is, in the polarized light irradiation apparatus 100 without the light blocking plate 30 installed, the polarized light emitted from the polarizing element 25 is not blocked by the light blocking plate 30, so the polarizing element 25 when viewed in the Z-axis direction It is wider than the area in which) is provided or the area in which the opening 27 is formed, and the light whose polarization axis is deteriorated is likely to be irradiated onto the work W. In contrast, in the polarized light irradiation device 1 according to the first embodiment, of the polarized light emitted from the polarizing element 25, the inner side of the light shielding plate 30, that is, the light shielding plate 30 from the light shielding plate reflective surface 31 Since the polarized light is shielded by the light shielding plate 30, it is difficult to expand the irradiation area viewed in the Z-axis direction. For this reason, irradiation of the polarized light whose polarization axis characteristic has deteriorated outside the irradiation range to the work W is suppressed.

In addition, the inventors tested the irradiation state of the polarized light irradiated by the polarized light irradiation device 1 in the case where the light shielding plate 30 is provided and the case where it is not provided. 5 is a chart showing the test results of the irradiation state of polarized light. In the test, the polarized light irradiation apparatus 1 in which the opening 27 is opened in a range of 50 mm in width in the Y-axis direction, that is, ±25 mm in the Y-axis direction from just below the light source 5 In 100), polarized light was irradiated, and the polarization axis characteristics on the irradiated surface were measured by measuring polarized light at a plurality of measurement points. As a measuring point, in each of the polarized light irradiation device 1 (FIG. 3) of the shading plate 30 and the polarized light irradiating apparatus 100 (FIG. 4) without the shading plate 30, immediately below the light source 5, Polarization axis characteristics were measured at a position at a distance of ±20 mm, a position at a distance of ±30 mm, and a position at a distance of ±40 mm in the Y-axis direction from immediately below the light source 5.

In this test, in the polarized light irradiation device 1 of the light shielding plate 30 and the polarized light irradiation device 100 without the light shielding plate 30 immediately below the light source 5, polarized light having a polarization axis of 0.02° Could be detected. In addition, at a position of ±20 mm from immediately below the light source 5, in the polarized light irradiation device 1 of the shading plate 30 and the polarized light irradiating device 100 without the shading plate 30, the polarization axis is The polarized light becoming 0.06° could be detected.

In contrast, polarized light is detected in the polarized light irradiation apparatus 100 without the shading plate 30 at a position of ±30 mm from directly below the light source 5 and ±40 mm from immediately below the light source 5. Although this was possible, the polarized light could not be detected in the polarized light irradiation apparatus 1 having the light shielding plate 30 at these positions. That is, in the polarized light irradiation apparatus 100 without the light shielding plate 30 at a position of ±30 mm from immediately below the light source 5, the polarized light having a polarization axis of 0.15° can be detected, and immediately below the light source 5 At a position of ±40 mm from the bottom, the polarized light irradiating apparatus 100 without the light shielding plate 30 could detect the polarized light having a polarization axis of 0.30°. On the other hand, in the polarized light irradiation apparatus 1 provided with the shading plate 30, polarized light could not be detected at these measurement points. As a result of these, it was confirmed that the polarized light emitted from the opening 27 is not irradiated to the outside of the light shielding plate 30.

In the polarized light irradiation device 1 according to the first embodiment, the opening 27 is viewed from the opening direction of the opening 27 on the emission side of the polarized light from the opening 27 formed in the polarizing element holding portion 26. Since the light shielding plate 30 disposed surrounding) is provided, the light shielding plate 30 can shield the polarized light toward the outside of the region where the opening 27 is formed when viewed in the same direction. Thereby, it is possible to make it difficult to diffuse the polarized light emitted from the polarizing element 25, and it is possible to suppress irradiation of the polarized light whose polarization axis characteristics are deteriorated to the work W outside the irradiation range.

[Embodiment 2]

The polarized light irradiation device 40 according to the second embodiment has substantially the same configuration as the polarized light irradiation device 1 according to the first embodiment, but a transparent member is provided on the light shielding plate to shield the space inside the light shielding plate. There are features. Other configurations are the same as those of the first embodiment, so the description thereof is omitted and the same reference numerals are given.

6 is a cross-sectional view of the polarized light irradiation device according to the second embodiment as viewed in the X-axis direction. The polarized light irradiation device 40 according to the second embodiment, similarly to the polarized light irradiation device 1 according to the first embodiment, a reflector 10 that controls the distribution of light emitted from the light source 5, and the incident A filter 20 that emits only ultraviolet rays of light, a polarizing element 25, and a polarizing element holding part 25 for holding the polarizing element 25 are provided. Further, on the side of the polarizing element holding portion 26 facing the light source 5, a light shielding plate 50 is provided which is formed in a substantially rectangular shape and blocks polarized light. In the same manner as the light shielding plate 30 of the polarized light irradiating device 1 according to the first embodiment, the light shielding plate 50 is formed of a light shielding plate reflective surface 51 that reflects light.

In addition, in the polarized light irradiation device 40 according to the second embodiment, a transparent space occludes the space inside the light shielding plate 50 at an end of the light shielding plate 50 on the opposite side to the side where the opening 27 is located. The glass plate 52 which is a member is provided. That is, the light shielding plate 50 is formed in a direction in which the length direction of the square cylinder becomes the Z-axis direction, and the side opposite to the work W, that is, the end opposite to the end of the polarizing element holding part 26 side, is formed to open. However, the glass plate 52 is formed so as to close the opening portion of the light shielding plate 50.

The glass plate 52 is made of glass, which is a transparent member that transmits light, and is formed in the shape of a rectangular plate having a shape substantially the same as that in the case where the shape of the light-shielding plate 50 is viewed in the Z-axis direction. It is provided at the end of the light shielding plate 50 in a direction parallel to the element 25. Thereby, the glass plate 52 closes the inner space of the light shielding plate 50 and shields the inner space of the light shielding plate 50 with respect to the outside of the light shielding plate 50.

7 is a view viewed in the direction of arrow B-B in FIG. 6. 8 is a view viewed in the direction of arrow C-C in FIG. 7. The light shielding plate 50 is provided with a supply/exhaust part 55 in a plurality of portions. The air supply/exhaust portion 55 includes an air supply portion 56 formed on one of the four wall surfaces constituting the light shielding plate 50, and an exhaust portion 57 formed on a wall surface opposite to the wall surface. Preferably, among the four walls of the light shielding plate 50, the air supply unit 56 is installed on one of the two walls facing the X-axis direction and located at the end of the X-axis direction, and the other wall. The exhaust part 57 is provided in the.

The air supply unit 56 is formed in a pipe shape, and is attached so as to communicate with the wall surface of the light blocking plate 50. A hole communicating with the inside of the pipe-shaped air supply unit 56 is formed in the portion of the wall of the light blocking plate 50 to which the air supply unit 56 is attached, and thereby the air supply unit 56 is It communicates with the inner space. A plurality of air supply portions 56 formed in this way (three in the second embodiment) are provided on the same wall surface of the light shielding plate 50. A blower (not shown) such as external high-pressure air is connected to the air supply unit 56 installed in this way, and the wind sent from the air blower flows in the air supply unit 56.

In addition, of the four wall surfaces of the light shielding plate 50, the exhaust part 57 is located at the end of the X-axis direction and one of the two wall surfaces facing the X-axis direction, the wall surface on which the air supply part 56 is installed, and It is installed on the opposite wall. The exhaust portion 57 is formed by a hole penetrating through the wall surface, whereby the exhaust portion 57 communicates the inner space and the outer side of the light shielding plate 50. A plurality of exhaust portions 57 formed in this way (three in the second embodiment) are provided on the same wall surface of the light shielding plate 50 as in the air supply portion 56.

The polarized light irradiation device 40 according to the second embodiment has the above-described configuration, and the operation thereof will be described below. In the polarized light irradiation device 40, when an alignment treatment is performed on a workpiece W such as an alignment film of a liquid crystal panel or an alignment film of a viewing angle compensation film, light including ultraviolet rays is emitted from the light source 5. As a result, only ultraviolet rays are emitted from the filter 20 when passing through the filter 20, and polarized light composed of ultraviolet rays vibrating in the reference direction is emitted when the polarizing element 25 of the ultraviolet rays is emitted. do. The polarized light emitted from the polarizing element 25 passes through the inner side of the light shielding plate 50 as it is or is reflected from the reflecting surface 51 of the light shielding plate, so that the polarization element holding part 26 of the light shielding plate 50 is positioned. It faces the direction of the opposite end.

Since the glass plate 52 is provided at the opposite end of the light shielding plate 50 to the polarizing element holding portion 26 side, the polarized light directed in this direction enters the glass plate 52. Since the glass plate 52 is made of a transparent member, the polarized light incident on the glass plate 52 passes through the glass plate 52 as it is, and is emitted from a side opposite to the side on which the polarized light is incident. do. The polarized light that has passed through the glass plate 52 in this way is irradiated onto the work W in the direction of the work W.

In this way, when the light source 5 of the polarized light irradiation device 40 is turned on and orientation treatment is performed on the work W, the light shielding plate 50 is formed by high-pressure air connected to the air supply unit 56. The cooling wind (E) is made to flow inside of, and the polarizing element 25 is cooled. Specifically, air is sent to the air supply unit 56 as cooling wind E by high-pressure air, and air is supplied from the air supply unit 56 to the inside of the light shielding plate 50. Since the light-shielding plate 50 has an exhaust part 57 on the side opposite to the side on which the air-supply part 56 is installed, when air is sent from the air supply part 56 to the inside of the light-shielding plate 50, the sent air Accordingly, air inside the shading plate 50 is extruded from the exhaust part 57 and exhausted to the outside of the shading plate 50.

When the light source 5 of the polarized light irradiation device 40 is turned on, light is emitted and heat is generated, but the polarized light irradiation device 40 transmits light emitted from the light source 5 to the polarizing element 25. Since it is formed so as to condense light in the vicinity of, the heat generated by the light source 5 during light emission is also easily collected in the polarizing element 25 by radiation. For this reason, when the light source 5 is turned on, the temperature of the polarizing element 25 is liable to rise, and accordingly, the temperature of the air inside the shading plate 50 is liable to rise, but the light shielding plate from the air supply unit 56 By sending air to the inside of 50 and discharging the air in the light shielding plate 50 from the exhaust part 57, it is possible to replace air having a high temperature with air having a low temperature.

Thereby, the air inside the light shielding plate 50 whose temperature is lowered performs heat exchange with the polarizing element 25 whose temperature has increased, and thus the temperature of the polarizing element 25 can be lowered. In this way, the air supply/exhaust unit 55 consisting of the air supply unit 56 and the exhaust unit 57 cools the polarizing element 25 by sending air to the inside of the light blocking plate 50 and releasing the air in the light blocking plate 50. It is possible to make the possible cooling wind E flow inside the light shielding plate 50, and the temperature of the polarizing element 25 is reduced by radiating heat to the cooling wind E.

Further, since the inside of the light shielding plate 50 is blocked by the glass plate 52, dust or the like does not enter the inside of the light shielding plate 50. For this reason, dust or the like becomes difficult to adhere to the polarizing element 25 that emits polarized light irradiated to the work W, and the polarizing element 25 is less likely to be contaminated.

In the polarized light irradiation device 40 according to the second embodiment, the glass plate 52 is provided at the opposite end of the light shielding plate 50 to the side where the opening 27 of the polarizing element holding portion 26 is located. , It is possible to prevent contaminants from adhering to the polarizing element 25. Accordingly, it is possible to suppress a decrease in the extinction ratio in the polarizing element 25. As a result, the performance of photo-alignment can be maintained over a long period of time.

In addition, since the light-shielding plate 50 has a supply and exhaust portion 55 formed in a plurality of portions, and the cooling wind E flows through the supply and exhaust portion 55 inside the light-shielding plate 50, the cooling wind E The polarizing element 25 can be cooled. As a result, deterioration of the polarizing element 25 due to an increase in the temperature of the polarizing element 25 can be suppressed, and a decrease in the extinction ratio can be suppressed more reliably.

[Modified example]

In addition, in the polarized light irradiation device 40 according to the second embodiment described above, the supply and exhaust portions 55 are formed on the wall surface of the light shielding plate 50 facing the X-axis direction, but the supply and exhaust portions 55 are at different positions. It may be formed in. 9 is a modified example of the polarized light irradiation device according to the second embodiment, and is an explanatory diagram when the light shielding plate is viewed in the Y-axis direction. 10 is a view viewed in the direction of arrow D-D in FIG. 9. The supply/exhaust part 55 may be provided on, for example, a wall surface facing the Y-axis direction among four wall surfaces of the light shielding plate 50 as shown in FIGS. 9 and 10. Specifically, the supply/exhaust part 55 is located at the end of the Y-axis direction and among the two walls facing the Y-axis direction, an air supply part 56 is installed on one wall, and an exhaust part 57 is provided on the other wall. It may be installed by being formed.

In this case, for example, when a plurality of polarizing elements 25 are arranged in a row in the X-axis direction, a plurality of air supply units 56 and exhaust units are provided corresponding to the positions of the polarizing elements 25 in the X-axis direction. It is preferable that (57) is formed. In this way, by installing the air supply unit 56 and the exhaust unit 57 corresponding to the polarizing element 25, cooling wind flowing inside the light shielding plate 50 by the air supply unit 56 and the exhaust unit 57 (E) can be made to flow by making it correspond to each polarizing element 25. Thereby, the polarizing element 25 can be cooled more reliably, and deterioration of the polarizing element 25 caused by an increase in temperature can be suppressed more reliably.

In addition, in the polarized light irradiation device 40 according to the second embodiment described above, a case in which a blower is connected to the air supply unit 56 has been described, but the present invention is not limited thereto. For example, it may be a case in which a blower is connected to the pipe-shaped exhaust part 57 and air is removed from the exhaust part 57 by using the blower. In addition, both of the air supply unit 56 and the exhaust unit 57 have a pipe shape, and the cooling wind E may be circulated by an air circulation device.

Further, in the polarized light irradiation devices 1 and 40 described above, the reflective plate 10 is made of glass and the reflective surface 11 is formed of a multilayer film, but the reflecting plate 10 may be made of other materials. The reflecting plate 10 may be made entirely of metal such as aluminum, for example. In addition, the reflective surface 11 does not need to be formed in a strictly elliptical shape.

Further, in the polarized light irradiation devices 1 and 40 described above, the light source 5 is described using a so-called tubular discharge lamp, but the light source 5 may be other than a discharge lamp. The light source 5 is, for example, light including ultraviolet rays, such as arranged in a linear shape by separating small lamps such as LED chips, laser diodes, and organic ELs capable of emitting ultraviolet rays having a wavelength of 200 nm to 400 nm. As long as it emits light, it may be anything other than a discharge lamp.

[Embodiment 3]

Next, an ultraviolet irradiation device 210 (also referred to as "polarized light irradiation device 210". The same hereinafter) according to an embodiment of the present invention will be described based on the drawings. FIG. 11 is a perspective view showing a schematic configuration of an ultraviolet irradiation device according to an embodiment, FIG. 12 is a view of an ultraviolet irradiation device according to the embodiment viewed from the Y-axis direction, and FIG. It is a schematic diagram showing the configuration of a polarizing element.

The polarized light irradiation device 210 of the embodiment shown in FIG. 11 is a polarization axis PB parallel to a predetermined reference direction (shown by arrows in FIG. 11, and vibration) on the surface of the work W as an object for alignment treatment. It is a device that irradiates ultraviolet rays (UC) of (also referred to as a direction). The polarized light irradiation device 210 of the embodiment is used for manufacturing an alignment film of a liquid crystal panel, an alignment film of a viewing angle compensation film, a polarizing film, and the like. The polarized light irradiation device 210 mainly irradiates the surface of the work W with ultraviolet rays UC whose wavelength is 365 [nm] as a desired wavelength. In addition, the term "ultraviolet ray" in the present embodiment refers to light in the wavelength range from 340 [nm] to 400 [nm], for example.

In addition, the polarization axis PB of the ultraviolet ray UC irradiated to the surface of the work W is appropriately set according to the structure of the work W, its use, or a required specification. Hereinafter, the width direction of the work (W) is referred to as the X-axis direction, the longitudinal direction of the work (W) is referred to as the Y-axis direction, and the direction orthogonal to the Y-axis direction and the X-axis direction is Z It is called the axial direction. In addition, with respect to the direction parallel to the Z-axis, the direction toward the tip end of the arrow indicating the direction of the Z-axis is referred to as upward, and the direction opposite to the direction toward the tip end of the arrow indicating the direction of the Z-axis is referred to as downward.

As shown in FIG. 11, the polarized light irradiation device 210 vibrates in all directions in the same manner and has a wavelength of about 200 [nm] to 900 [nm] including ultraviolet rays, visible rays, and infrared rays (U) It has a light source 211 emitting light, a first polarizing element 216, and an absorption type polarizing element 218. Further, a mirror 212 and a filter 214 may be provided.

The light source 211 is a tubular lamp such as a mercury lamp in which noble gases such as mercury, argon, xenon, etc. are enclosed in an ultraviolet transmissive glass tube, or a metal halide lamp in which a metal halide such as iron or iodine is additionally enclosed in the mercury lamp. And at least a linear light emitting portion. The longitudinal direction of the light emitting portion of the light source 211 is parallel to the Y-axis direction. The light U emitted by the light source 211 includes ultraviolet rays, visible rays, and infrared rays having a wavelength of about 200 [nm] to 900 [nm], and is so-called non-polarized light having various polarization axis components. In this embodiment, one light source 211 is provided, and is further disposed above the first polarizing element 216, the absorption type polarizing element 218 and the work W.

The mirror 212 is installed above the light source 211 and reflects the light U emitted from the light source 211 toward the work W. In addition, the light U emitted from the light source 211 is reflected by the mirror 212 is referred to as light U'. As the mirror 212, a parallel parabolic mirror, a condensing elliptical mirror, or a mirror of another shape can be used.

The filter 214 transmits ultraviolet (UA) among the light (U) emitted from the light source 211 and the light (U') reflected by the mirror 212, and suppresses transmission other than the ultraviolet (UA). ). The filter 214 emits ultraviolet rays UA among the light U emitted from the light source 211 and the light U'reflected by the mirror 212 to the first polarizing element 216 side. Further, the ultraviolet rays UA emitted by the filter 214 are so-called unpolarized light having various polarization axis components. In this embodiment, the filter 214 is provided below the light source 211 and above the first polarizing element 216.

In addition, in the present invention, the filter 214 may be composed of only a single filter 214 if it is possible to suppress heating of the first polarizing element 216 and the absorption type polarizing element 218, and a plurality of filters 214 Each layer may be configured. In addition, as constituting the filter 214, a bandpass filter that transmits light such as ultraviolet rays of a desired wavelength, or a dichroic filter that reflects or absorbs visible light, and transmits light such as ultraviolet rays of a desired wavelength. Can be used. In addition, the filter 214 may form a film having a function of blocking visible light on one surface, and a film having a function of blocking infrared light on the other surface, for example, and having a function of blocking visible light. Any of the film and the film having a function of blocking infrared light may be formed on the surface.

The first polarizing element 216 is irradiated with light (ultraviolet UA) that passes through the filter 214. The first polarizing element 216 directs ultraviolet rays (UB) as polarized light of the polarization axis PA parallel to the reference direction among the light (ultraviolet rays UA) transmitted through the filter 214 toward the absorption type polarizing element 218. Penetrates. That is, the first polarizing element 216 passes through the filter 214, and from ultraviolet rays UA having several polarization axis components vibrating in all directions in the same manner, the ultraviolet rays UB of the polarization axis PA vibrating only in the reference direction. ) Is taken out. In addition, ultraviolet rays UB of the polarization axis PA that vibrate only in the reference direction are generally referred to as linear polarization.

In this embodiment, the first polarizing element 216 is provided below the filter 214 and above the surface of the absorption type polarizing element 218. As shown in FIG. 13, the first polarizing element 216 is a nano-sized grid in which titanium oxide is deposited with a height of 50 to 300 nm, a width of 10 to 200 nm, and a pitch of 50 to 300 nm on the surface of the glass plate 216a. 216b) is a regularly formed, so-called wire grid polarizing element. As the first polarizing element 216, for example, UVT260A manufactured by Moxtek can be used. In addition, as shown in FIG. 13, it is preferable that the first polarizing element 216 faces the side of the glass plate 216a, that is, the side where the grating 216b is not formed, toward the filter 214 side.

The absorption-type polarizing element 218 is irradiated with light (ultraviolet ray UB) that passes through the first polarizing element 216. The absorption type polarizing element 218 transmits the polarized light (ultraviolet ray (UC)) of the polarization axis (PB) parallel to the reference direction among the light (ultraviolet ray (UB)) transmitted through the first polarizing element 216 to the workpiece (W). It penetrates toward. That is, the absorption-type polarizing element 218 extracts ultraviolet rays (UC) of the polarization axis (PB) vibrating only in the reference direction from the ultraviolet rays (UB) that pass through the first polarization element 216 and have a polarization axis (PA). Is to do. In addition, the ultraviolet (UC) of the polarization axis (PB) vibrating only in the reference direction is generally referred to as linear polarization. In addition, the polarization axes (PA, PB) of the ultraviolet rays (UA, UB, UC) are the electric and magnetic fields of the ultraviolet rays (UA, UB).

In this embodiment, the absorption type polarizing element 218 is provided below the filter 214 and above the surface of the work W. The absorption type polarizing element 218 is formed of metal nanoparticles arranged in a predetermined direction included in the glass plate, and among the ultraviolet rays (UB) transmitted through the first polarizing element 216, a polarization axis (PB) that is orthogonal to the reference direction ( An example is shown in FIG. 11) as a polarizing element that absorbs ultraviolet rays, and transmits ultraviolet rays UC of a polarization axis PB parallel to the reference direction. As the absorption polarizing element 218, for example, colorpol (registered trademark) UV375BC5 manufactured by CODIXX can be used.

The polarized light irradiation apparatus 210 according to the embodiment of the above-described configuration places the work W under the absorption-type polarizing element 218 and emits light U from the light source 211. Then, the light U emitted by the light source 211 is directly or reflected by the mirror 212 and irradiated onto the filter 214. In the polarized light irradiation device 210, the filter 214 transmits ultraviolet rays UA toward the first polarizing element 216, and suppresses transmission of light other than ultraviolet rays UA. In addition, the polarized light irradiation device 210 transmits the ultraviolet rays UB of the polarization axis PA parallel to the reference direction among the ultraviolet rays UA by the first polarizing device 216 toward the absorption type polarizing device 218. In addition, the polarized light irradiation device 210 allows the absorption-type polarizing element 218 to direct the ultraviolet (UC) of the polarization axis (PB) parallel to the reference direction of the ultraviolet (UB) toward the light irradiation area of the surface of the work (W). It transmits and performs orientation treatment on the surface of the work W.

By using the absorption type polarizing element 218 in the polarized light irradiation apparatus 210 according to the above-described embodiment, compared to the case of using the wire grid type polarizing element which is a reflective polarizing element, one of the polarized light characteristics Extinction ratio can be increased. In addition, in the wire grid type polarizing element, there are so-called front and rear sides of the surface on which the wire grid is formed and the surface on which the wire grid is not formed, and the extinction ratio is changed by the front and back of the wire grid polarizing element. However, the absorption type polarizing element 218 is handled because the metal nanoparticles formed inside the absorption type polarizing element 218 absorb light that vibrates other than the reference direction, so there is no so-called front and rear, like a wire grid polarizing element. This is easy.

In addition, in the polarization light irradiation device 210, the absorption type polarizing element 218 that absorbs ultraviolet rays of the polarization axis PB crossing the reference direction is previously irradiated with ultraviolet rays UB parallel to the polarization axis PA, Irradiation of light other than (UB) is regulated. For this reason, the polarized light irradiation device 210 can reduce the amount of light absorbed by the absorption type polarizing element 218, specifically, light absorbed by the metal nanoparticles formed inside the absorption type polarizing element 218. . If the amount of light absorbed by the metal nanoparticles can be reduced, the temperature rise of the absorption type polarizing element 218 is suppressed, and the likelihood that the absorption type polarizing element 218 becomes high temperature decreases, for example, absorption type polarization Problems such as damage to the element 218 can be suppressed. Accordingly, even when the absorption type polarizing element 218 is used in the polarized light irradiation device 210, problems such as damage of the absorption type polarizing element 218 can be suppressed.

In addition, in the polarized light irradiation device 210, since ultraviolet (UB) is irradiated to the absorption-type polarizing element (281) and irradiation of light of a wavelength other than the ultraviolet (UB) is regulated, the absorption type polarizing element 218 is It is possible to suppress a decrease in the extinction ratio of the absorption type polarizing element 218 than when the light U and the light U'are directly irradiated. In addition, the extinction ratio refers to a value obtained by dividing the maximum transmittance of ultraviolet ray (UC), which is linearly polarized light of the absorption type polarizing element 218, by the minimum transmittance of ultraviolet ray (UC), which is linearly polarized light. That is, the extinction ratio = maximum transmittance/minimum transmittance. In addition, the transmittance refers to the degree of radiance of ultraviolet rays (UC) passing through the first polarizing element 216 and the absorption type polarizing element 218, and incident on the first polarizing element 216 and the absorption type polarizing element 218. It is a value (%) obtained by dividing the radiation divergence of ultraviolet (UA) and multiplying it by 100. That is, transmittance (%) = (radiation degree of ultraviolet ray (UC)/radiation degree of ultraviolet ray (UA))×100.

In the polarized light irradiation device 210, since the filter 214 suppresses the transmission of ultraviolet rays of a short wavelength, ultraviolet rays of a short wavelength can be suppressed from being irradiated to the first polarizing element 216 and the absorption type polarizing element 218. . In addition, since the filter 214 suppresses the transmission of ultraviolet rays, visible rays, and infrared rays of long wavelengths, the polarized light irradiation apparatus 210 is configured to use the first polarizing element 216 and the absorption type ultraviolet rays, visible rays, and infrared rays. Irradiation to the polarizing element 218 can be suppressed. Accordingly, the polarized light irradiation device 210 can reliably suppress a decrease in the lifespan of the first polarizing element 216 and the absorption type polarizing element 218, and also the first polarizing element 216 and the absorption type polarizing element The decrease in the extinction ratio of (218) can be reliably suppressed.

In addition, since the polarized light irradiation device 210 uses a mercury lamp or a metal halide lamp as the light source 211, the lifespan and extinction ratio of the first polarizing element 216 and the absorption type polarizing element 218 are suppressed. Ultraviolet (UC) of a sufficient amount of light can be irradiated to the work W, and the required time for irradiating light to the object can be suppressed.

In addition, the polarized light irradiation device 210 uses both the first polarizing element 216 and the absorption type polarizing element 218, so that either the first polarizing element 216 or the absorption type polarizing element 218 The extinction ratio is further improved than the case of using only.

Here, the relative illuminance, extinction ratio, and temperature change of the absorption-type polarizing element due to the presence or absence of the filter 214, the first polarizing element 216, and the absorption-type polarizing element 218 were evaluated. In addition, it is preferable that the surface temperature of the absorption type polarizing element 218 is 350°C or less. When the surface temperature of the absorption type polarizing element 218 exceeds 350° C., the absorption type polarizing element 218 is damaged by heat, which is not preferable. In addition, the relative illuminance is the condition of Comparative Example 2, that is, only the absorption polarizing element 218 is installed, and the input power per unit length for the light source 211 [W/cm] (hereinafter, simply referred to as “input power”) It is a value obtained by normalizing the 365 nm illuminance when set to 120 to 100. In addition, the illuminance was measured by the illuminometer main body: Ushio Electric Corporation's UIT-250, sensor: Ushio Electric Corporation's UVD-S365.

In addition, in Comparative Example 1, only the first polarizing element 216 was used, and the input power [W/cm] was set to 120. In Comparative Example 2, only the absorption type polarizing element 218 was used, and the input power [W/cm] was set to 120. In Comparative Example 3, only the absorption type polarizing element 218 was used and the input power [W/cm] was set to 160. In Comparative Example 4, the input power [W/cm] was set to 160 using the filter 214 and the absorption polarizing element 218. In Comparative Example 5, the filter 214 and the absorption type polarizing element 218 were used, and the input power [W/cm] was set to 200. In the present invention 1, the first polarizing element 216 and the absorption type polarizing element 218 were used, and the input power [W/cm] was set to 160. In the present invention 2, the first polarizing element 216 and the absorption type polarizing element 218 were used, and the input power [W/cm] was set to 200. In the present invention 3, the input power [W/cm] was set to 160 using the filter 214, the first polarizing element 216, and the absorption type polarizing element 218. In the present invention 4, the input power [W/cm] is set to 220 using the filter 214, the first polarizing element 216, and the absorption type polarizing element 218.

Fig. 14 shows the results. As apparent from the present inventions 1 and 2 of FIG. 14, by using the first polarizing element 216 and the absorption type polarizing element 218, the extinction ratio satisfies 60:1 and the temperature of the absorption type polarizing element 218 is increased. It becomes possible to suppress Further, as is apparent from the present inventions 3 and 4 of FIG. 14, the extinction ratio can be further improved by using the filter 214 in addition to the configurations of the present inventions 1 and 2. In particular, even if the input power [W/cm] is set to 220, the relative illuminance can be increased while maintaining the temperature of the absorption-type polarizing element 218 at 350° C. or lower, and the extinction ratio can also satisfy 70:1.

In addition, the first polarizing element 216 is not limited to the above configuration. For example, as shown in Fig. 15, two wire grid polarizing elements may be overlapped with the lattice-formed surfaces to form the first polarizing element 216. Further, the first polarizing element 216 may be an absorption type polarizing element.

(Modification example)

Fig. 16 is a side view showing a schematic configuration of a modified example of the ultraviolet irradiation device 220 (also referred to as "polarized light irradiation device 220", hereinafter the same) according to the first embodiment.

In this modified example, a polarized light irradiating device 220 in which the first polarizing element 216 and the absorption type polarizing element 218 are integrated is shown. Even in such a configuration, it becomes possible to improve the extinction ratio as in the third embodiment.

17 is a side view showing a schematic configuration of another modified example of the ultraviolet irradiation device according to the first embodiment.

In this modified example, the first polarizing element 216 and the absorption type polarizing element 218 are integrated, and between the first polarizing element 216 and the absorption type polarizing element 218, the first polarizing element 216 And an ultraviolet irradiation device 230 (also referred to as "polarized light irradiation device 230") interposed with a medium 219 substantially equal to the refractive index of the absorption type polarizing element 218. Even in such a configuration, it becomes possible to improve the extinction ratio as in the third embodiment.

Although several embodiments of the present invention have been described, these embodiments have been presented as examples, and there is no intention to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the invention described in the claims and their equivalent ranges, just as they are included in the scope and summary of the invention.

1, 40, 100: polarized light irradiation device 5: light source
10: reflector 11: reflective surface
12: void portion 20: filter
21: filter frame 25: polarizing element
26: polarizing element holding part 27: opening
30, 50: shading plate 31, 51: shading plate reflective surface
52: glass plate (transparent member) 55: supply and exhaust part
56: air supply unit 57: exhaust unit
210: 220, 230: polarized light irradiation device 211: light source
212: mirror 214: filter
216: first polarizing element 218: absorption type polarizing element
219: medium U: light
UA: Ultraviolet (light) UB: Ultraviolet (polarized light)
UC: Ultraviolet (polarized light) PA: Polarization axis
PB: Polarization axis W: Work (object)

Claims (6)

A light source that emits light;
A filter that emits ultraviolet rays by irradiating the light emitted from the light source;
A polarizing element installed on a side of the filter opposite to the light source, and emitting polarized light by incident the ultraviolet rays;
A polarizing element holding unit holding the polarizing element and having an opening through which the polarized light emitted from the polarizing element is transmitted; And
The polarizing light irradiation apparatus comprising a light shielding plate provided to protrude from the polarizing element holding unit on a side of the polarizing element holding unit opposite to the light source and installed surrounding the opening. The method of claim 1,
A polarized light irradiation apparatus, wherein a transparent member is provided at an end portion of the light shielding plate on a side opposite to the side in which the opening is located, to block a space inside the light shielding plate. The method of claim 2,
The polarized light irradiation device, wherein a supply and exhaust portion is formed in a plurality of portions on the light shielding plate. A light source that emits light;
A first polarizing element that transmits polarized light of a polarization axis parallel to a predetermined reference direction among the light emitted from the light source; And
And an absorption type polarizing element that transmits polarized light of a polarization axis parallel to a predetermined reference direction among the light transmitted through the first polarizing element,
A polarized light irradiation device, wherein a filter is installed between the light source and the first polarizing element. The method of claim 4,
The light source is a mercury lamp or a metal halide lamp, polarized light irradiation device. delete

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