TWI617867B - Polarized light illuminating device - Google Patents

Abstract

The invention provides a polarized light irradiation device, which can obtain good polarization axis characteristics in an irradiation range. The present invention includes a light source 5, a filter 20, a polarizing element 25, a polarizing element holding portion 26, and a light shielding plate 30. The light source 5 emits light. The filter 20 is irradiated with light emitted from the light source 5 and emits ultraviolet rays. The polarizing element 25 is disposed on a side of the filter 20 facing the light source 5, and enters ultraviolet rays and emits polarized light. The polarizing element holding portion 26 holds the polarizing element 25 and has an opening portion 27 that transmits polarized light emitted from the polarizing element 25. The light shielding plate 30 is disposed on a side of the polarizing element holding portion 26 opposite to the light source 5, and is disposed so as to surround the opening portion 27.

Description

Polarized light irradiation device

Embodiments of the present invention relate to a polarized light irradiation device used in the manufacture of liquid crystal panels and the like.

A rubbing process is known as a technique for performing an alignment treatment on an alignment film during the manufacture of a liquid crystal panel or the like. However, in recent years, as a technique to replace the rubbing process, an alignment film is irradiated with polarized light of a predetermined wavelength. A technique for performing an alignment process, so-called photo-alignment, has attracted attention. As a polarized light irradiation device that is a device for performing the light alignment, for example, a combination of a rod lamp as a linear light source and a wire grid polarizing element having a wire grid grid has been proposed. Polarized light irradiation device.

Compared with a polarizing element using a vapor-deposited film or a Brewster angle, the extinction of polarized light emitted from a wire grid polarizing element is less dependent on the angle of light incident on the polarizing element. Therefore, even for divergent light such as light emitted from a rod-shaped lamp, as long as the incident angle is within a range of ± 45 °, polarized light having a relatively good extinction ratio can be obtained over the entire area irradiated by the light. Therefore, in this partial In the vibratory light irradiation device, the length of the rod-shaped lamp is set to a length corresponding to the width of the alignment film as the object to be processed, and the alignment film is moved unidirectionally relative to the polarized light irradiation device during the alignment treatment. , A single rod-shaped lamp can be used to perform alignment processing of a large-area alignment film.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2009-265290

[Patent Document 2] Japanese Patent Laid-Open No. 2011-145381

Here, such a polarized light irradiation device is configured to irradiate light to the irradiation surface of the alignment film with as much light amount as possible, specifically, by condensing light from a rod-shaped lamp on The polarizing element is provided to suppress the radiation loss directed to the outside of the polarizing element. However, when the light from the rod-shaped lamp is condensed on the polarizing element like this, the polarized light transmitted through the polarizing element is diffused. Furthermore, on the illuminated surface irradiated with the diffused polarized light, the polarized light will expand beyond the area of the polarizing element. It is known that the polarization axis of polarized light irradiated to a position exceeding the area of the polarizing element deteriorates. Irradiation of the light whose polarization axis has been deteriorated to an alignment film as an object to be irradiated causes a decrease in the characteristics of the alignment film.

The present invention has been made in view of the circumstances, and an object thereof is to provide a polarization The light irradiation device suppresses the irradiation of polarized light whose polarization axis characteristics are degraded outside the irradiation range. A second object of the present invention is to provide a polarized light irradiation device using an absorption-type polarizing element.

The polarized light irradiation device according to the embodiment includes a light source, a filter, a polarizing element, a polarizing element holding portion, 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 disposed on the side of the filter that is opposite to the light source, and enters ultraviolet rays and emits polarized light. The polarizing element holding portion holds the polarizing element and has an opening that transmits polarized light emitted from the polarizing element. The light shielding plate is disposed on a side of the polarizing element holding portion opposite to the light source, and is disposed to surround the opening portion. A transparent member that closes the inner space of the light shielding plate is disposed at an end portion on the opposite side of the side where the opening portion of the light shielding plate is located. Air supply and exhaust portions are formed in a plurality of portions of the light shielding plate. The polarized light irradiation device of the embodiment includes a light source that emits light, a first polarizing element that transmits, from the light emitted from the light source, polarized light having a polarization axis parallel to a predetermined reference direction, and an absorption-type polarizing element, Among the light transmitted through the reflective polarizing element, polarized light having a polarization axis parallel to a predetermined reference direction is transmitted. A filter is provided between the light source and the first polarizing element. The light source is a mercury lamp or a metal halide lamp.

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

1, 40, 100‧‧‧‧ polarized light irradiation device

5‧‧‧ light source

10‧‧‧Reflector

11‧‧‧Reflective surface

12‧‧‧Gap section

20‧‧‧ Filter

21‧‧‧ filter frame

25‧‧‧polarizing element

26‧‧‧Polarization element holding section

27‧‧‧ opening

30, 50‧‧‧ Shading plate

31, 51‧‧‧ Reflective surface of shading plate

52‧‧‧ glass plate (transparent member)

55‧‧‧Air supply and exhaust

56‧‧‧Gas supply department

57‧‧‧Exhaust

210, 220, 230‧‧‧‧ polarized light irradiation device (ultraviolet irradiation device)

211‧‧‧light source

212‧‧‧Reflector

214‧‧‧ Filter

216‧‧‧1st polarizing element

216a‧‧‧glass plate

216b‧‧‧ lattice

218‧‧‧ Absorptive Polarizing Element

219‧‧‧ Medium

C‧‧‧Light Center

E‧‧‧ cooling air

F‧‧‧ Focus

L1, L3 ‧‧‧ part of the light

L2, L4‧‧‧‧Partially polarized light

m1, m2‧‧‧‧polarized light

PA, PB‧‧‧ polarization axis

U, U ' ‧‧‧ light

UA‧‧‧ Ultraviolet (light)

UB, UC‧‧‧ultraviolet (polarized light)

W‧‧‧Workpiece (object)

X, Y, Z‧‧‧ axis

Y1‧‧‧arrow

FIG. 1 is an exploded perspective view showing a configuration of a polarized light irradiation device according to the first embodiment.

FIG. 2 is a cross-sectional arrow A-A view of a single-dot chain line A-A of the polarized light irradiation device shown in FIG.

FIG. 3 is an explanatory diagram showing a light irradiation state in the polarized light irradiation device shown in FIG. 1.

FIG. 4 is an explanatory diagram of a polarized light irradiation device without a light shielding plate.

5 is a cross-sectional view of a polarized light irradiation device according to the second embodiment as viewed in the X-axis direction.

Fig. 6 is a B-B arrow view of Fig. 5.

Fig. 7 is a view taken along the arrow C-C of Fig. 6.

8 is a diagram illustrating a modification of the polarized light irradiation device according to the second embodiment when the light shielding plate is viewed in the Y-axis direction.

FIG. 9 is a D-D arrow view of FIG. 8.

FIG. 10 is a perspective view showing a schematic configuration of the ultraviolet irradiation device according to the embodiment.

FIG. 11 is a view of the ultraviolet irradiation device according to the embodiment as viewed from the Y-axis direction.

FIG. 12 is a schematic diagram showing a configuration of a first polarizing element 216 of the ultraviolet irradiation device according to the embodiment.

FIG. 13 is a schematic diagram showing a modification of the ultraviolet irradiation device according to the embodiment.

FIG. 14 is a diagram showing a modified example of the ultraviolet irradiation device according to the embodiment.

FIG. 15 is a diagram showing another modified example of the ultraviolet irradiation device according to the embodiment.

The polarized light irradiation device 1 and the polarized light irradiation device 40 according to the embodiments described below include a light source 5, a filter 20, a polarizing element 25, a polarizing element holding portion 26, a light shielding plate 30, and a light shielding plate 50. The light source 5 emits light. The filter 20 is irradiated with light emitted from the light source 5 and emits ultraviolet rays. The polarizing element 25 is disposed on a side of the filter 20 opposite to the light source 5, and enters ultraviolet rays and emits polarized light. The polarizing element holding portion 26 holds the polarizing element 25 and has an opening portion 27 that transmits polarized light. The light-shielding plate 30 and the light-shielding plate 50 are disposed on a side of the polarizing element holding portion 26 opposite to the light source 5, and are disposed so as to surround the opening portion 27.

Further, in the polarized light irradiation device 40 of the embodiment described below, a transparent member that closes the inner space of the light shielding plate 50 is disposed at an end on the opposite side of the side where the opening 27 of the light shielding plate 50 is located. That is, the glass plate 52.

Further, in the polarized light irradiation device 40 of the embodiment described below, air supply and exhaust portions 55 are formed in a plurality of portions of the light shielding plate 50.

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. Absorptive Polarization Element 218 Among the light transmitted through the first polarizing element 216, polarized light having a polarization axis parallel to a predetermined reference direction is transmitted.

In the polarized light irradiation device 210 according to the embodiment described below, a filter 214 is provided between the light source 211 and the first polarizing element 216.

In the polarized light irradiation device 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 the first embodiment will be described based on the drawings. FIG. 1 is an exploded perspective view showing a configuration of a polarized light irradiation device according to the first embodiment. FIG. 2 is a cross-sectional view of the polarized light irradiation device shown in FIG. 1 when viewed in the X-axis direction. The polarized light irradiation device 1 shown in FIG. 1 and FIG. 2 is used, for example, in the production of 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 the ultraviolet ray irradiated to the surface of the workpiece W as the object to be processed can be appropriately set according to the structure and use of the workpiece W, or a required specification. Hereinafter, the width direction of the workpiece W is referred to as the X-axis direction, and the long-side direction (also referred to as the conveying direction) of the workpiece W that is orthogonal to the X-axis direction is referred to as the Y-axis direction, and is referred to as the Y-axis direction and the X-axis direction. The orthogonal 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 reflection plate 10 that controls light distribution of light emitted from the light source 5, and a filter 20 that is disposed on the reflection plate 10. The traveling direction side of the light distribution light is controlled by the reflection plate 10, and the filter 20 is incident on the light emitted from the light source 5 and the light distribution distribution is controlled by the reflection plate 10 to emit ultraviolet rays; a polarizing element 25 is disposed on the Filter A light-emitting side of 20 emits polarized light by entering the ultraviolet rays emitted from the filter 20; and a polarizing element holding portion 26 holds the polarizing element 25.

The light source 5 is a rod-shaped or linear light source. The light source 5 is, for example, a high-pressure mercury lamp in which a rare gas such as mercury, argon, or xenon is enclosed in an ultraviolet-transmissive glass tube, or a metal halide lamp in which a metal halide such as iron or iodine is further enclosed in the high-pressure mercury lamp. Equal tube type lamp, and has at least a linear light emitting portion. The long-side direction of the light-emitting portion of the light source 5 is parallel to the X-axis direction, and the length of the light-emitting portion of the light source 5 is longer than the width of the workpiece W. The light source 5 can emit light including ultraviolet rays having a wavelength of 200 nm to 400 nm from the linear light-emitting portion, and the light emitted by the light source 5 is so-called non-polarized light having various polarization axis components.

Further, the reflecting plate 10 has a reflecting surface 11 on a surface facing the light source 5 and reflecting light emitted from the light source 5. The reflecting surface 11 has a shape (a shape viewed in the axial center direction) when viewed in a direction along the axis of the light source 5 formed in a rod shape, that is, a shape in which a part of the ellipse is opened when viewed in the X-axis direction. . The reflection plate 10 is provided such that the lamp center C, which is the axis of the light source 5, is located on one of the two ellipses of the ellipse of the reflection surface 11, and the other one is open on the focal side. With the shape of the elliptical part of the reflecting surface 11 as described above, the reflecting plate 10 becomes a so-called condensing type reflecting plate, that is, when the light source 5 is arranged at one of the focal points, The light emitted from the light source 5 is collected near another focal point (focus point F in FIG. 3). The reflecting plate 10 is arranged in a direction opening in the Z-axis direction.

The reflecting plate 10 extends along the light source 5 formed in a rod shape in the shape and parallel to the light source 5. Furthermore, the reflection plate 10 has an elliptical opening in the reflection surface 11 A portion 12 on the opposite side to the portion where the curvature of the ellipse becomes the largest is formed in the circumferential direction of the ellipse or in the Y-axis direction. That is, when viewed from the light source 5, the void portion 12 is the side opposite to the oval opening side of the reflective surface 11 formed in the Z-axis direction. The reflecting plate 10 communicates the space inside and outside the ellipse by the gap portion 12. In addition, the reflecting plate 10 has a configuration of a cold mirror having a base material containing glass and a reflecting surface 11 formed of a multilayer film. When polarized light is irradiated on the object to be irradiated by the polarized light irradiation device 1, the light source 5 emits light while generating heat, but the air whose temperature rises due to the heat flows upward and escapes from the gap portion 12 to above the reflecting plate 10. . Accordingly, the polarized light irradiation device 1 irradiates the workpiece W with ultraviolet rays without the temperature becoming excessively high.

Further, the filter 20 includes a conventional band-pass filter that transmits only a specific wavelength of light emitted from the light source 5, so that, for example, 254 nm or Ultraviolet light of a predetermined wavelength such as 365nm is transmitted, and light transmission of other wavelengths is restricted. The filter 20 is disposed on the elliptical opening side of the reflection surface 11 in the Z-axis direction with respect to the light source 5 and the reflection plate 10. The periphery of the filter 20 in the X-axis direction and the Y-axis direction is surrounded by a filter frame 21, and thus the filter 20 is held by the filter frame 21.

Like the filter 20, the polarizing element 25 is disposed on the elliptical opening side of the reflecting surface 11 in the Z-axis direction with respect to the light source 5 and the reflecting plate 10. The reflecting plate 10 as a condensing-type reflecting plate is provided so that light can be collected on the polarizing element 25.

The polarizing element 25 is formed by arranging a plurality of linear electric conductors (such as metal wires of chromium or aluminum alloy) on a substrate such as quartz glass at equal intervals and in parallel. Wire grid polarizing element. The longitudinal direction of the electrical conductor is orthogonal to the reference direction. The pitch of the electric conductors is preferably 1/3 or less of the wavelength of the ultraviolet rays emitted from the light source 5. Among the ultraviolet rays emitted from the filter 20 by incident light emitted from the light source 5, the polarizing element 25 reflects or absorbs most of the ultraviolet rays whose polarization axis is parallel to the longitudinal direction of the electric conductor, and makes the polarization axis and electric The ultraviolet rays orthogonal to the longitudinal direction of the conductor pass through and irradiate the workpiece W. The polarizing element 25 may extract, as polarized light, ultraviolet rays that oscillate only in a reference direction from the ultraviolet rays emitted from the filter 20 disposed between the light source 5 and the polarizing element 25. Further, the polarizing element 25 can extract light having a polarization axis that vibrates only in a reference direction from light having various polarization axis components emitted from the light source 5 and that vibrates equally in all directions. In addition, light whose polarization axis vibrates only in the reference direction is generally referred to as linearly polarized light. The polarization axis refers to the vibration direction of the electric and magnetic fields of light.

The polarizing element holding portion 26 holds a polarizing element 25 that enters ultraviolet rays and emits polarized light, and includes an opening portion 27 that transmits polarized light emitted from the polarizing element 25. The periphery of the polarizing element 25 in the X-axis direction and the Y-axis direction is surrounded by the polarizing element holding portion 26, whereby the polarizing element 25 is held by the polarizing element holding portion 26.

In addition, in the first embodiment, the polarizing element 25 is arranged so that the longitudinal direction of the electric conductor is parallel to the Y-axis direction, and ultraviolet rays whose polarization axis is parallel to the X-axis direction are passed through. That is, in the first embodiment, the reference direction is parallel to the X-axis direction.

A light shielding plate 30 is provided on a side of the polarizing element holding portion 26 that faces the light source 5. The light shielding plate 30 is disposed so as to surround the opening portion 27 of the polarizing element holding portion 26. Specifically, the polarizing element 25 is formed in a rectangular plate shape, The opening 27 formed in the polarizing element holding portion 26 that holds the polarizing element 25 is also formed in a rectangular shape corresponding to the polarizing element 25 in the same manner as the polarizing element 25.

The light-shielding plate 30 is located on the exit side of the polarized light in the opening portion 27 of the polarizing element holding portion 26, protrudes from the polarizing element holding portion 26 in a direction opposite to the direction in which the light source 5 and the like are located, and when viewed in the opening direction of the opening portion 27, The light shielding plate 30 is arranged so as to surround the opening 27. That is, the shape of the inner side of the light shielding plate 30 is formed into a substantially rectangular tube shape having a shape slightly larger than the opening 27, and is formed so as to surround the entire opening 27 of the rectangle from all sides when viewed in the Z-axis direction. The axial direction of the cylinder is arranged in the direction of the Z-axis direction. Therefore, an end portion of the light shielding plate 30 facing the polarizing element holding portion 26 is opened. The inner surface of the light-shielding plate 30 thus provided is formed as a light-shielding plate reflection surface 31 that reflects light, for example, by disposing aluminum foil or the like.

The light shielding plate 30 is preferably provided within a range of 5 mm on all four sides of the corner tube with respect to the opening portion 27 of the polarizing element holding portion 26. The height of the light shielding plate 30 in the Z-axis direction is preferably at least 5 mm or more from the irradiation surface of the work W when the work W is irradiated with the polarized light irradiation device 1.

The polarized light irradiation device 1 according to the first embodiment has the above-mentioned configuration, and its operation will be described below. FIG. 3 is an explanatory diagram showing a light irradiation state in the polarized light irradiation device shown in FIG. 1. When the polarized light irradiation device 1 is used to align the workpiece W, which is an irradiated object, such as an alignment film of a liquid crystal panel or an alignment film of a viewing angle compensation film, a transport device (not shown) of the workpiece W is used in the Y-axis direction. The workpiece W is conveyed in the direction of the parallel arrow Y1, and is emitted from the light source 5. Ultraviolet light.

Part of the light emitted from the light source 5 enters the filter 20 toward the filter 20 (for example, L1 in FIG. 3). The filter 20 transmits only ultraviolet rays without transmitting light other than ultraviolet rays, and emits only ultraviolet rays from a surface on the opposite side of the surface on the light incident side.

The ultraviolet rays emitted from the filter 20 enter the polarizing element 25 located on the opposite side of the side where the light source 5 in the filter 20 is located and held by the polarizing element holding portion 26. In the polarizing element 25, most of the ultraviolet rays whose polarization axis is parallel to the long side direction of the electric conductor constituting the polarizing element 25 among incident ultraviolet rays do not pass through, but only the polarizing axis is orthogonal to the long side direction of the electric conductor. Ultraviolet rays pass through. As a result, the polarizing element 25 emits only ultraviolet rays vibrating in the reference direction from the surface on the side opposite to the surface on which the filter 20 is located. The polarized light containing ultraviolet rays vibrating in the reference direction emitted from the polarizing element 25 is transmitted through the opening 27 of the polarizing element holding portion 26 and is irradiated to the workpiece W through the inside of the light shielding plate 30, which is disposed on the The filter 20 in the polarizing element holding portion 26 is opposite to the side on which the filter 20 is located. In the workpiece W, an alignment treatment is performed using polarized light containing the ultraviolet rays.

Then, as described above, a part of the polarized light emitted from the polarizing element 25 by passing the light emitted from the light source 5 through the filter 20 and the polarizing element 25 is directed toward the light shielding plate 30 (for example, L2 in FIG. 3). . That is, a part of the polarized light emitted from the polarizing element 25 passes through the opening 27 of the polarizing element holding portion 26 and faces the light-shielding plate reflective surface 31 in the light-shielding plate 30 to reach the light-shielding plate reflective surface 31. 30 is an opening surrounding the polarizing element holding portion 26 when viewed in the Z-axis direction The arrangement of the unit 27. As a result, the polarized light reaching the light-shielding plate reflection surface 31 travels in the Y-axis direction in the reverse direction of the direction before reaching the light-shielding plate reflection surface 31, and as a result is blocked by the light-shielding plate 30.

As described above, the inner surface of the light-shielding plate 30 blocked by polarized light is formed as the light-shielding plate reflective surface 31 that reflects light. Therefore, the polarized light reaching the light-shielding plate reflective surface 31 is reflected by the light-shielding plate reflective surface 31 and faces the light-shielding plate. The incident direction of the reflecting surface 31 is opposite to the incident direction. That is, the polarized light reflected by the light-shielding plate reflection surface 31 faces the light-shielding plate reflection surface 31 facing the light-shielding plate reflection surface 31 opposite to the light-shielding plate reflection surface 31 that reflects the polarized light, and faces away from the polarizing element holding portion 26. Accordingly, the polarized light reflected by the light-shielding plate reflection surface 31 is irradiated to the workpiece W in the direction of the workpiece W.

In addition, a part of the light emitted from the light source 5 is directed in the direction of the reflective surface 11 of the reflective plate 10, and the light in the direction of the reflective surface 11 is reflected by the reflective surface 11 and directed to the filter 20 (for example, L3 in FIG. 3) . The light directed in the direction of the filter 20 in this way 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 reflecting surface 11 of the reflecting plate 10 reflects the light emitted from the light source 5 and reaching the reflecting surface 11 to condense the light near the polarizing element 25 to a position where the filter 20 in the polarizing element 25 is located. Focus F on the opposite side of the side. Therefore, the ultraviolet rays emitted from the filter 20 are irradiated to the filter 20 after being reflected by the reflecting surface 11 and are incident on the polarizing element 25 which is located immediately before the focal point F when viewed from the filter 20. The polarizing element 25 that has entered the ultraviolet rays from the filter 20 emits polarized light containing ultraviolet rays that vibrate in the reference direction. The polarized light is illuminated through the inside of the light shielding plate 30 Shoot to workpiece W.

Furthermore, of the polarized light emitted from the polarizing element 25 by reflecting and passing through the filter 20 and the polarizing element 25 by the reflecting surface 11 of the reflecting plate 10, a part of the polarized light passes through the focal point F and then faces the light shielding plate 30 (for example, L4 in Figure 3). The polarized light is reflected by the light-shielding plate in the same manner as the polarized light that is directly incident from the light source 5 to the filter 20 and passes through the filter 20 and the polarizing element 25 to reach the light-shielding plate reflective surface 31 and is reflected by the light-shielding plate reflective surface 31. The surface 31 reflects toward the direction of the workpiece W. That is, the polarized light reaching the light-shielding plate reflection surface 31 is blocked 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 workpiece W by the light-shielding plate reflection surface 31. Thereby, the polarized light reflected by the light-shielding plate reflection surface 31 is irradiated to the workpiece W.

Since the polarized light irradiation device 1 according to the first embodiment shields a part of the polarized light emitted from the polarizing element 25 by the light shielding plate 30, the polarized light can be irradiated to the workpiece W without excessive expansion. FIG. 4 is an explanatory diagram of a polarized light irradiation device without a light shielding plate. That is, when the polarized light irradiating device 100 without the light shielding plate 30 is used to irradiate the workpiece W with polarized light, the light emitted from the light source 5 passes through the filter 20 and the polarizing element 25 directly and exits from the polarizing element 25. The polarized light is irradiated to the workpiece W (for example, m1 in FIG. 4) in the same manner as in the case of the polarized light irradiation device 1 of the first embodiment. If the orbits of the two ultraviolet rays affected by the presence or absence of the light-shielding plate are compared, a part of the polarized light is blocked by the light-shielding plate 30 in the polarized light irradiation device 1 of Embodiment 1, so that the polarized light does not reach the light-shielding plate 30 The direction of travel is beyond the position in the Y-axis direction of the light shielding plate 30 and is reflected by the light shielding plate reflection surface 31. In contrast, in the polarized light irradiation device 100 without the light shielding plate 30, The polarized light is not blocked by the light-shielding plate 30, and therefore faces the outside of the light-shielding plate 30 formed in a rectangular tube shape beyond the position where the light-shielding plate 30 is provided in the polarized light irradiation device 1 of the first embodiment.

Similarly, the polarized light emitted from the polarizing element 25 passes through the filter 20 and the polarizing element 25 after being reflected by the reflecting plate 11 and is directed toward the reflecting plate 10 after being reflected from the reflecting plate 11 and is irradiated with the polarized light of the first embodiment. In the case of the device 1, the workpiece W (for example, m2 in FIG. 4) is similarly irradiated. If the two orbits of the ultraviolet rays affected by the presence or absence of the light-shielding plate are compared, the polarized light reflected by the reflecting surface 11 is also not blocked by the light-shielding plate 30, so a part of the polarized light is directed toward the light-shielding plate formed in a rectangular tube shape. The direction of the outer side of 30 is beyond the position where the light shielding plate 30 is disposed in the polarized light irradiation device 1 of the first embodiment.

That is, in the polarized light irradiation device 100 without the light-shielding plate 30, the polarized light emitted from the polarizing element 25 is not blocked by the light-shielding plate 30, and therefore extends beyond the area where the polarizing element 25 is arranged when viewed in the Z-axis direction. Or the area formed by the opening 27, it is easy to irradiate the workpiece W with the light whose polarization axis has deteriorated. In contrast, in the polarized light irradiation device 1 of the first embodiment, among the polarized light emitted from the polarizing element 25, the polarized light reaching the light shielding plate 30 from the inside of the light shielding plate 30, that is, the light shielding plate reflection surface 31 is blocked by the light shielding plate. 30 occlusion, it is difficult to expand the irradiation area when viewed in the Z-axis direction. As a result, the workpiece W is prevented from being irradiated with polarized light whose polarization axis characteristics are out of the irradiation range.

In addition, the present inventors and others have provided the light shielding plate 30 with respect to the irradiation state of the polarized light irradiated by the polarized light irradiation device 1 and have not provided the light shielding plate 30. The situation was tested. Table 1 is a graph of a test result on the irradiation state of polarized light. The test was performed by irradiating the polarized light with the polarized light irradiating device 1 and the polarized light irradiating device 100 and measuring the polarization axis characteristics of the irradiated surface on the polarized light at a plurality of measurement points. In the light irradiation device 100, the width of the opening portion 27 in the Y-axis direction is 50 mm, that is, the opening portion 27 is opened within a range of ± 25 mm in the Y-axis direction from directly below the light source 5. As measurement points, the polarized light irradiation device 1 (FIG. 3) without the light shielding plate 30 and the polarized light irradiation device 100 (FIG. 4) without the light shielding plate 30 are respectively directly below the light source 5 from A position of ± 20mm in the Y-axis direction directly below the light source, a position of ± 30mm in the Y-axis direction directly below the light source 5 and a position of ± 40mm in the Y-axis direction directly below the light source 5 Measurement of polarization axis characteristics.

In the test, both the polarized light irradiating device 1 having the light shielding plate 30 and the polarized light irradiating device 100 without the light shielding plate 30 can detect the polarized light having the polarization axis directly below the light source 5. Furthermore, at a position ± 20 mm from directly below the light source 5, both the polarized light irradiation device 1 with the light shielding plate 30 and the polarized light irradiation device 100 without the light shielding plate 30 can detect polarized light having a polarization axis of 0.06 °. .

In contrast, polarized light can be detected in the polarized light irradiation device 100 without the light-shielding plate 30 at a position ± 30 mm from the light source 5 and at a position ± 40 mm from the light source 5 Position, the polarized light was not detected in the polarized light irradiation device 1 having the light shielding plate 30. That is, at a position ± 30 mm from directly below the light source 5, the polarized light irradiation device 100 without the light shielding plate 30 can detect polarized light having a polarization axis of 0.15 °, and at a position ± 40 mm from directly below the light source 5 The polarized light irradiation device 100 without the light shielding plate 30 can detect polarized light having a polarization axis of 0.30 °. On the other hand, in the polarized light irradiation device 1 having the light-shielding plate 30, the polarized light was not detected at the measurement point. From the above, it was confirmed that the polarized light emitted from the opening 27 was not irradiated to the outside of the light shielding plate 30.

In the polarized light irradiation device 1 according to the first embodiment, the exit side of the polarized light formed in the opening portion 27 of the polarizing element holding portion 26 is provided to surround the opening portion 27 when viewed in the opening direction of the opening portion 27. The light-shielding plate 30 is arranged in such a manner that polarized light directed toward the outside of the area formed by the opening portion 27 when viewed in the direction can be blocked by the light-shielding plate 30. This makes it difficult to expand the polarized light emitted from the polarizing element 25, and it is possible to suppress the workpiece W from being irradiated with the polarized light whose polarization axis characteristics have been degraded outside the irradiation range.

[Embodiment 2]

The polarized light irradiation device 40 according to the second embodiment has a configuration substantially the same as that of the polarized light irradiation device 1 according to the first embodiment, but has a feature that a transparent member that shields the inner space of the light shielding plate is disposed in the light shielding plate. Since the other configurations are the same as those of the first embodiment, descriptions thereof are omitted and the same reference numerals are attached.

5 is a cross-sectional view of a polarized light irradiation device according to the second embodiment as viewed in the X-axis direction. The polarized light irradiating device 40 of the second embodiment has the same configuration as the polarized light irradiating device 1 of the first embodiment: a reflecting plate 10 that controls the light distribution of light emitted from the light source 5; and a filter 20 that controls only the incident light. The polarizing element 25; and a polarizing element holding portion 26 that holds the polarizing element 25. A light-shielding plate 50 formed in a substantially rectangular cylindrical shape and blocking polarized light is provided on a side of the polarizing element holding portion 26 facing the light source 5. Similarly to the light shielding plate 30 included in the polarized light irradiation device 1 of Embodiment 1, the inner surface of the light shielding plate 50 is formed as a light shielding plate reflection surface 51 that reflects light.

Further, in the polarized light irradiation device 40 according to the second embodiment, a transparent member, which is a glass that closes the inner space of the light shielding plate 50, is disposed at an end portion on the opposite side of the side where the opening 27 of the light shielding plate 50 is located.板 52。 Board 52. That is, the light-shielding plate 50 is formed so that the longitudinal direction of the corner tube becomes the Z-axis direction, and the side opposite to the workpiece W, that is, the end opposite to the end on the side of the polarizing element holding portion 26 is opened. It is formed, but the glass plate 52 is formed so as to close the opening portion in the light shielding plate 50.

The glass plate 52 is formed into a rectangular plate shape by using a transparent member that transmits light, that is, glass. The rectangular plate shape is substantially the same as the shape of the light shielding plate 50 when viewed in the Z-axis direction, that is, the shape of a rectangular tube. The glass plate 52 is provided at an end portion of the light shielding plate 50 in a direction parallel to the polarizing element 25. Accordingly, 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 from the outside of the light shielding plate 50.

Fig. 6 is a B-B arrow view of Fig. 5. Fig. 7 is a view taken along the arrow C-C of Fig. 6. Air supply / exhaust portions 55 are formed in a plurality of portions of the light shielding plate 50. The air supply and exhaust portion 55 includes an air supply portion 56 and an exhaust portion 57. The air supply portion 56 is formed on one of the four wall surfaces constituting the light shielding plate 50. The air exhaust portion 57 is formed. On a wall surface opposite to the wall surface. Specifically, among the four wall surfaces of the light shielding plate 50, an air supply portion 56 is provided on one of the two wall surfaces facing the X-axis direction at the end portion in the X-axis direction, and the other wall surface is provided. The upper part is provided with an exhaust section 57.

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

Among the four wall surfaces of the light shielding plate 50, the other of the two wall surfaces facing the X-axis direction at the end portion in the X-axis direction is opposite to one of the wall surfaces provided with the air supply portion 56. An exhaust portion 57 is provided on the wall surface. The exhaust portion 57 is formed by a hole penetrating the wall surface, and thus the exhaust portion 57 communicates with the inner space and the outer side of the light shielding plate 50. As with the air supply portion 56, a plurality of (three in the second embodiment) the exhaust portion 57 formed in this manner is provided on the same wall surface of the light shielding plate 50.

The polarized light irradiation device 40 according to the second embodiment has the structure described above, and its operation will be described below. When the polarized light irradiation device 40 performs an alignment process 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. Thus, when the light passes through the filter 20, only ultraviolet rays are emitted from the filter 20, and when the ultraviolet rays are emitted by the polarizing element 25, they emit polarized light having ultraviolet rays vibrating in a reference direction. The polarized light emitted from the polarizing element 25 directly passes through the inside of the light shielding plate 50 or is reflected by the light shielding plate reflecting surface 51, and thus faces the opposite side of the end of the side where the polarizing element holding portion 26 in the light shielding plate 50 is located. The direction of the end.

A glass plate 52 is disposed at an end on the opposite side of the end on the polarizing element holding portion 26 side of the light shielding plate 50, and therefore, the polarized light directed in the above direction enters the glass plate 52. Since the glass plate 52 has a transparent member, light can be transmitted. Therefore, the polarized light incident on the glass plate 52 is transmitted directly through the glass plate 52 and is emitted from a surface on the opposite side of the surface on which the polarized light is incident. The polarized light transmitted through the glass plate 52 in this manner is irradiated to the workpiece W in the direction of the workpiece W.

As described above, when the light source 5 of the polarized light irradiation device 40 is turned on to orient the workpiece W, the high-pressure air connected to the air supply unit 56 is used to flow the cooling air E inside the light shielding plate 50 to perform the polarizing element 25. Of cooling. Specifically, high-pressure air is used to send air to the air supply unit 56 as cooling air E, and air is sent from the air supply unit 56 to the inside of the light shielding plate 50. The exhaust portion 57 is formed on the surface of the light shielding plate 50 opposite to the surface on which the air supply portion 56 is provided. Therefore, when air is sent from the air supply portion 56 to the inside of the light shielding plate 50, Corresponding to the air, the air inside the light shielding plate 50 is extruded from the exhaust portion 57 and is exhausted to the outside of the light shielding plate 50.

When the light source 5 of the polarized light irradiating device 40 is turned on, heat is also generated when the light is emitted, and the polarized light irradiating device 40 collects light emitted from the light source 5. Since it collects in the vicinity of the polarizing element 25, the heat generated by the light source 5 at the time of light emission also tends to concentrate on the polarizing element 25 by radiation. Therefore, when the light source 5 is turned on, the temperature of the polarizing element 25 is likely to rise, and the temperature of the air inside the light-shielding plate 50 is also likely to rise along with this. The air inside the light-shielding plate 50 is exhausted from the exhaust portion 57 from the inside, and the air having a higher temperature can be replaced with air having a lower temperature.

Thereby, the air inside the light-shielding plate 50 having a reduced temperature performs heat exchange with the temperature-increasing polarizing element 25, and the temperature of the polarizing element 25 can be reduced. As described above, the air supply / exhaust portion 55 having the air supply portion 56 and the air discharge portion 57 sends air into the inside of the light shielding plate 50 and exhausts the air in the light shielding plate 50, so that it can be inside the light shielding plate 50. The cooling air E that can cool the polarizing element 25 flows, and the temperature of the polarizing element 25 is reduced by dissipating heat to the cooling air E.

In addition, since the light shielding plate 50 is closed inside by the glass plate 52, dust and the like are not allowed to enter the inside of the light shielding plate 50. Therefore, it is also difficult for dust and the like to adhere to the polarizing element 25 for emitting polarized light irradiated to the workpiece W, and the polarizing element 25 is difficult to be contaminated.

The polarized light irradiating device 40 of the second embodiment described above is provided with the glass plate 52 at the end on the opposite side of the side where the opening 27 of the polarizing element holding portion 26 in the light shielding plate 50 is located, so that the polarizing element 25 can be prevented Dirt on it. This can suppress a decrease in the extinction ratio in the polarizing element 25. As a result, the photo-alignment performance can be maintained for a long time.

Further, the air supply / exhaust portion 55 is formed in a plurality of portions of the light shielding plate 50, and The cooling air E is caused to flow by the air supply / exhaust portion 55 inside the light shielding plate 50. Therefore, the polarizing element 25 can be cooled by the cooling air E. 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 more surely suppressed.

[Modification]

In the polarized light irradiation device 40 according to the second embodiment, the air supply and exhaust unit 55 is formed on the wall surface of the light shielding plate 50 facing the X-axis direction. However, the air supply and exhaust unit 55 may be formed in addition to this Position. 8 is a diagram illustrating a modification of the polarized light irradiation device according to the second embodiment when the light shielding plate is viewed in the Y-axis direction. FIG. 9 is a D-D arrow view of FIG. 8. For example, as shown in FIGS. 8 and 9, the air supply and exhaust unit 55 may be provided on a wall surface facing the Y-axis direction among the four wall surfaces of the light shielding plate 50. Specifically, the air supply and exhaust unit 55 may be provided by providing an air supply unit 56 on one of the two wall surfaces facing the Y axis direction at the end portion located in the Y axis direction and facing the other side. An exhaust portion 57 is formed on one wall surface.

At this time, for example, when a plurality of polarizing elements 25 are arranged in the X-axis direction, it is preferable to form a plurality of air supply portions 56 and exhaust portions 57 corresponding to the positions of the polarizing elements 25 in the X-axis direction. . By providing the air supply portion 56 and the exhaust portion 57 corresponding to the polarizing element 25 in this manner, the cooling air E flowing inside the light shielding plate 50 and each of the polarizing elements 25 can be caused by the air supply portion 56 and the exhaust portion 57. Flow accordingly. Thereby, the polarizing element 25 can be cooled more reliably, and the deterioration of the polarizing element 25 due to temperature rise can be more surely suppressed.

The polarized light irradiation device 40 according to the second embodiment is Although the case where the blower is connected to the air supply unit 56 has been described, it is not limited to this. For example, it may be an example in which a blower is connected to the tubular exhaust portion 57 and air is sucked from the exhaust portion 57 using the blower. Further, the cooling air E may be circulated by the air circulation device so that both the air supply portion 56 and the exhaust portion 57 are tubular.

In the polarized light irradiating device 1 and the polarized light irradiating device 40, the base material of the reflection plate 10 is glass and the reflection surface 11 is formed of a multilayer film. However, the reflection plate 10 may be provided by other materials. For example, the reflecting plate 10 may be entirely made of a metal such as aluminum. Moreover, the reflecting surface 11 may not be strictly formed into an oval shape.

In the polarized light irradiating device 1 and the polarized light irradiating device 40, it has been described that the light source 5 uses a tube-shaped so-called discharge lamp, but the light source 5 may be other than a discharge lamp. As the light source 5, for example, a small light emitting diode (Light Emitting Diode (LED) chip, a laser diode, an organic electroluminescence (EL), and the like that emits ultraviolet light having a wavelength of 200 nm to 400 nm is arranged and separated. It is linear or the like, as long as it emits light containing ultraviolet rays, it may be other than a discharge lamp.

[Embodiment 3]

Next, an ultraviolet irradiation device 210 (also referred to as "polarized light irradiation device 210". Hereinafter, the same) will be described based on the drawings. 10 is a perspective view showing a schematic configuration of the ultraviolet irradiation device according to the embodiment, FIG. 11 is a view of the ultraviolet irradiation device according to the embodiment viewed from the Y-axis direction, and FIG. 12 is a diagram showing a configuration of a first polarizing element of the ultraviolet irradiation device according to the embodiment. Schematic.

The polarized light irradiation device 210 of the embodiment shown in FIG. A device for irradiating a surface of a workpiece W of a processing target object with ultraviolet UC having a polarization axis PB (indicated by an arrow in FIG. 1 and also referred to as a vibration direction) parallel to a predetermined reference direction. The polarized light irradiation device 210 according to the embodiment is used, for example, in the production of an alignment film for a liquid crystal panel, an alignment film for a viewing angle compensation film, or a polarizing film. The polarized light irradiation device 210 mainly irradiates the surface of the workpiece W with ultraviolet UC having a wavelength of 365 [nm], which is a desired wavelength. The "ultraviolet rays" referred to in this embodiment are light in a wavelength band of 340 [nm] to 400 [nm], for example.

The polarization axis PB of the ultraviolet UC irradiated to the surface of the workpiece W can be appropriately set according to the structure and use of the workpiece W, or a required specification. Hereinafter, the width direction of the workpiece W is referred to as the X-axis direction, the longitudinal direction of the workpiece W orthogonal to the X-axis direction is referred to as the Y-axis direction, and the direction orthogonal to the Y-axis direction and the X-axis direction is referred to as Z. Axis direction. In the direction parallel to the Z axis, the direction facing the tip of the arrow indicating the direction of the Z axis is referred to as upward, and the direction facing the direction facing the tip of the arrow indicating the direction of the Z axis is referred to as the downward direction.

As shown in FIG. 10, the polarized light irradiation device 210 includes a light source 211, a first polarizing element 216, and an absorption-type polarizing element 218. The light source 211 emits a light having a wavelength of 200 [nm] to 900 [including the same vibration in all directions]. nm] ultraviolet light, visible light, and infrared light U. In addition, a reflector 212 and a filter 214 may be provided.

As the light source 211, a mercury lamp in which a rare gas such as mercury, argon, and xenon is enclosed in an ultraviolet-transmissive glass tube, or a tube lamp such as a metal halide lamp in which a metal halide such as iron or iodine is further enclosed in the mercury lamp, At least linear Glowing part. The long-side direction of the light-emitting portion of the light source 211 is parallel to the Y-axis direction. The light U emitted from 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 unpolarized light having various polarization axis components. In this embodiment, one light source 211 is provided, and is arranged above the first polarizing element 216, the absorption-type polarizing element 218, and the workpiece W.

The reflecting mirror 212 is provided above the light source 211 and reflects the light U emitted from the light source 211 toward the workpiece W. In addition, the light obtained by reflecting the light U emitted from the light source 211 through the reflecting mirror 212 is referred to as light U ′ . As the reflecting mirror 212, a parallel parabolic reflecting mirror, a condensing elliptical reflecting mirror, or other shaped reflecting mirrors can be used.

The filter 214 transmits ultraviolet light UA among the light U emitted from the light source 211 and the light U ′ reflected by the reflector 212, and suppresses (limits) transmission of light other than the ultraviolet UA. The filter 214 emits the ultraviolet light UA among the light U emitted from the light source 211 and the light U ′ reflected by the reflector 212 to the first polarizing element 216 side. The ultraviolet UA emitted from the filter 214 is 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, as long as the filter 214 can suppress the heating of the first polarizing element 216 and the absorption-type polarizing element 218, it may be composed of only a single filter 214, or a plurality of filters 214 may be overlapped and Make up. In addition, a band-pass filter that transmits light such as ultraviolet rays of a desired wavelength, or a dichroic filter that reflects or absorbs visible light rays and transmits light such as ultraviolet rays of a desired wavelength can be used. To form an optical filter 214. Further, the filter 214 may be, for example, A film having a function of cutting visible light is formed on one surface, and a film having a function of cutting infrared light is formed on the other surface. A film having a function of cutting visible light and a film having a function of cutting infrared light may be formed on the surface. Any of the functional films.

The first polarizing element 216 is irradiated with light (ultraviolet rays UA) transmitted through the filter 214. The first polarizing element 216 transmits ultraviolet light UB, which is polarized light whose polarization axis PA of the light (ultraviolet rays UA) transmitted through the filter 214 is parallel to the reference direction, to the absorption-type polarizing element 218. That is, the first polarizing element 216 extracts the ultraviolet rays UB whose polarization axis PA vibrates only in the reference direction from the ultraviolet rays UA having various polarization axis components that transmit the filter 214 and vibrate equally in all directions. In addition, the ultraviolet UB whose polarization axis PA vibrates only in the reference direction is generally referred to as linearly polarized light.

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. 12, the first polarizing element 216 is a so-called wire-grid polarizing element that is formed regularly on the surface of the glass plate 216 a with a height of 50 nm to 300 nm, a width of 10 nm to 200 nm, and a pitch of 50 nm to 300 nm Nano-sized grid 216b formed by vapor deposition of titanium oxide. As the first polarizing element 216, for example, UVT260A manufactured by Moxtek can be used. Furthermore, as shown in FIG. 12, the first polarizing element 216 preferably has a surface on the glass plate 216 a side, that is, on the side where the grid 216 b is not formed, facing the filter 214 side.

The absorption-type polarizing element 218 is irradiated with light (ultraviolet rays UB) transmitted through the first polarizing element 216. The absorption-type polarizing element 218 transmits the polarized light (ultraviolet UC) whose polarization axis PB of the light (ultraviolet UB) transmitted through the first polarizing element 216 is parallel to the reference direction to the workpiece W. That is, the absorption-type polarizing element 218 passes through the first The ultraviolet rays UB having the polarization axis PA of the polarizing element 216 extract the ultraviolet rays UC whose polarization axis PB vibrates only in the reference direction. In addition, ultraviolet rays UC that have the polarization axis PB vibrating only in the reference direction are generally referred to as linearly polarized light. The polarization axis PA and polarization axis PB of the ultraviolet UA, ultraviolet UB, and ultraviolet UC refer to vibration directions of the electric and magnetic fields of the ultraviolet UA and ultraviolet UB.

In this embodiment, the absorption-type polarizing element 218 is provided below the filter 214 and above the surface of the workpiece W. The absorptive polarizing element 218 is formed of metal nano particles arranged in a certain direction in a glass plate, and absorbs the polarization axis PB in the ultraviolet UB transmitted through the first polarizing element 216 to cross the reference direction (shown in FIG. 1). An example) is an ultraviolet polarizing element, and ultraviolet UC whose polarization axis PB is parallel to the reference direction is transmitted. As the absorption-type polarizing element 218, for example, colorpol (registered trademark) UV375BC5 manufactured by CODIXX can be used.

In the polarized light irradiation device 210 according to the embodiment having the above-mentioned configuration, the work W is placed under the absorption-type polarizing element 218 and the light U is emitted from the light source 211. Accordingly, the light U emitted from the light source 211 is directly or reflected by the reflecting mirror 212 and irradiates the filter 214. In the polarized light irradiation device 210, the filter 214 transmits ultraviolet UA to the first polarizing element 216, and suppresses transmission of light other than the ultraviolet UA. In the polarized light irradiation device 210, the first polarizing element 216 transmits ultraviolet rays UB whose polarization axis PA of the ultraviolet rays UA is parallel to the reference direction to the absorption-type polarization element 218. Furthermore, in the polarized light irradiation device 210, the absorption-type polarizing element 218 transmits the ultraviolet UC whose polarization axis PB in the ultraviolet UB is parallel to the reference direction to the light-irradiated area on the surface of the workpiece W, and performs an orientation treatment on the surface of the workpiece W. .

In the polarized light irradiation device 210 according to the embodiment having the above-mentioned configuration, by using the absorption-type polarizing element 218, it is possible to improve one of the characteristics of polarized light as compared with the case where a wire-grid polarizing element is used as a reflective polarizing element. Extinction ratio. In addition, the wire grid type polarizing element has a surface on which the wire grid is formed and a surface on which the wire grid is not formed, a so-called front and back surface. However, in the absorptive polarizing element 218, the metal nano-particles formed inside the absorptive polarizing element 218 absorb light that vibrates outside the reference direction, so there is no so-called surface such as a wire grid polarizing element, so the operation is easy .

Furthermore, in the polarized light irradiation device 210, the absorption-type polarizing element 218 that absorbs ultraviolet rays whose polarization axis PB intersects the reference direction is irradiated with ultraviolet UB that is parallel to the polarization axis PA in advance, and restricts irradiation of light other than the ultraviolet UB. Therefore, the amount of light absorbed by the absorption-type polarizing element 218 in the polarized light irradiation device 210, specifically, the amount of light absorbed by the metal nano-particles formed inside the absorption-type polarizing element 218 can be reduced. If the amount of light absorbed by the metal nano-particles can be reduced, the temperature rise of the absorption-type polarizing element 218 can be suppressed, and the possibility of the absorption-type polarizing element 218 becoming high temperature can be reduced. Therefore, for example, the cracking of the absorption-type polarizing element 218 can be suppressed. Class of bad conditions. Therefore, even if the absorption-type polarizing element 218 is used in the polarized light irradiation device 210, defects such as cracking of the absorption-type polarizing element 218 can be suppressed.

Furthermore, in the polarized light irradiation device 210, the absorption type polarizing element 218 is irradiated with ultraviolet UB, and light of a wavelength other than the ultraviolet UB is restricted. Therefore, it is the same as the case where the absorption type polarizing element 218 is directly irradiated with light U and light U ' The reduction of the extinction ratio of the absorption-type polarizing element 218 can be suppressed. The extinction ratio is a value obtained by dividing the maximum transmittance of the linearly polarized ultraviolet UC as the absorption-type polarizing element 218 by the minimum transmittance of the linearly polarized ultraviolet UC. That is, the extinction ratio = maximum transmittance / minimum transmittance. Further, the transmittance is the radiation divergence of the ultraviolet UC passing through the first polarizing element 216 and the absorption-type polarizing element 218 divided by the radiation divergence of the ultraviolet UA incident on the first polarization element 216 and the absorption-type polarizing element 218. Multiplied by 100 (%). That is, transmittance (%) = (radiation divergence of ultraviolet UC / radiation divergence of ultraviolet UA) × 100.

In the polarized light irradiation device 210, since the filter 214 suppresses transmission of ultraviolet rays of a short wavelength, it is possible to suppress irradiation of ultraviolet rays of a short wavelength to the first polarizing element 216 and the absorption-type polarizing element 218. Furthermore, in the polarized light irradiation device 210, the filter 214 suppresses transmission of ultraviolet rays, visible rays, and infrared rays of long wavelengths, and thus suppresses irradiation of ultraviolet rays, visible rays, and infrared rays of long wavelengths to the first polarizing element 216 and the absorption-type polarizing element. 218. Therefore, the polarized light irradiating device 210 can surely suppress the reduction of the life of the first polarizing element 216 and the absorption-type polarizing element 218, and can reliably suppress the reduction of the extinction ratio of the first polarizing element 216 and the absorption-type polarizing element 218.

Further, since the polarized light irradiation device 210 uses a mercury lamp or a metal halide lamp as the light source 211, it is possible to suppress the reduction in the life and extinction ratio of the first polarizing element 216 and the absorption-type polarizing element 218, and it is possible to sufficiently irradiate the workpiece W The amount of light ultraviolet UC suppresses the time required to irradiate the object with light.

Furthermore, in the polarized light irradiation device 210, the use of both the first polarizing element 216 and the absorptive polarizing element 218 is compared with the case where only the first polarizing element 216 or the absorptive polarizing element 218 is used. , Extinction ratio is further improved high.

Here, the contrast, the extinction ratio, and the temperature change of the absorption-type polarizing element that are affected by the presence or absence of the filter 214, the first polarization element 216, and the absorption-type polarizing element 218 are evaluated. The surface temperature of the absorption-type polarizing element 218 is preferably 350 ° C or lower. If the surface temperature of the absorption-type polarizing element 218 exceeds 350 ° C., the absorption-type polarizing element 218 is cracked due to heat, which is not preferable. In addition, the relative degree refers to the case where the absorption type polarizing element 218 is provided only under the conditions of Comparative Example 2 and the input power per unit length [W / cm] with respect to the light source 211 (hereinafter referred to as "input power") A value obtained by normalizing the illuminance at 365 nm when set to 120 to 100. In addition, the illuminance was measured using an illuminance meter body: UIT-250 manufactured by Ushio Electric Company, and a sensor: UVD-S365 manufactured by Ushio Electric Company.

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 filter 214 and the absorption-type polarizing element 218 were used, and the input power [W / cm] was set to 160. 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 are used, and the input power [W / cm] is set to 160. In the second aspect of the present invention, the first polarizing element 216 and the absorption-type polarizing element 218 are used, and the input power [W / cm] is set to 200. In the present invention 3, the filter 214, the first polarizing element 216, and the absorption-type polarizing element are used. 218 and the input power [W / cm] is set to 160. In the present invention 4, the filter 214, the first polarizing element 216, and the absorption-type polarizing element 218 are used, and the input power [W / cm] is set to 220.

The results are shown in Table 2. Table 2 is a table showing the evaluation results of the extinction ratio affected by the presence or absence of the filter 214, the first polarizing element 216, and the absorptive polarizing element 218 and the temperature of the absorptive polarizing element 218 in the ultraviolet irradiation device of the embodiment. It is clear from the invention 1 and the invention 2 of Table 2 that by using the first polarizing element 216 and the absorption-type polarization element 218, the extinction ratio satisfies 60: 1, and the temperature rise of the absorption-type polarization element 218 can be suppressed. Furthermore, it is clear from the invention 3 and the invention 4 of Table 2 that the use of the filter 214 in addition to the constitutions of the invention 1 and the invention 2 can further improve the extinction ratio. In particular, even if the input power [W / cm] is set to 220, the temperature of the absorptive polarizing element 218 can be kept below 350 ° C, the relative contrast can be improved, and the extinction ratio can satisfy 70: 1.

The first polarizing element 216 is not limited to the above configuration. For example, as shown in FIG. 13, the first polarizing element 216 may be formed by superimposing the grid-formed surfaces of two wire-grid polarizing elements on each other. The first polarizing element 216 may be an absorption-type polarizing element.

(Modification)

14 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”. The same applies hereinafter) of the first embodiment.

This modification shows a polarized light irradiation device 220 in which the first polarizing element 216 and the absorption-type polarizing element 218 are integrated. With this configuration, it is possible to improve the extinction ratio in the same manner as in the third embodiment.

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

This modification shows an ultraviolet irradiation device 230 in which the first polarizing element 216 and the absorption-type polarizing element 218 are integrated and the medium 219 is interposed between the first polarization element 216 and the absorption-type polarizing element 218. (Also referred to as "polarized light irradiation device 230"), the refractive index of the medium 219 is substantially the same as that of the first polarizing element 216 and the absorptive polarizing element 218. With this configuration, it is possible to improve the extinction ratio in the same manner as in the third embodiment.

Although some embodiments of the present invention have been described, these embodiments are merely examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and can be carried out in various ways without departing from the spirit of the invention. Omit, replace, change. These embodiments and modifications thereof are included in the scope or spirit of the invention, and are also included in the scope equivalent thereto.

1‧‧‧ polarized light irradiation device

5‧‧‧ light source

10‧‧‧Reflector

11‧‧‧Reflective surface

12‧‧‧Gap section

20‧‧‧ Filter

21‧‧‧ filter frame

25‧‧‧polarizing element

26‧‧‧Polarization element holding section

27‧‧‧ opening

30‧‧‧shield

31‧‧‧Shading plate reflective surface

C‧‧‧Light Center

W‧‧‧Workpiece (object)

Y, Z‧‧‧ axis

Claims (6)

A polarized light irradiating device, comprising: a light source that emits light; a filter that emits ultraviolet rays when irradiated with the light emitted from the light source; and a polarizing element that is disposed between the filter and the light source. A side opposite to the light source, the ultraviolet light is incident and the polarized light is emitted; a polarizing element holding part holding the polarizing element and having an opening for transmitting the polarized light emitted from the polarizing element; and a light shielding plate, The polarizing element holding portion is disposed on a side of the polarizing element holding portion opposite to the light source, protrudes from the polarizing element holding portion in a direction opposite to a direction in which the light source is located, and is disposed to surround the opening portion. The polarized light irradiation device according to item 1 of the scope of patent application, wherein an end portion on the opposite side of the side where the opening portion of the light shielding plate is located is provided with an end space that closes an inner space of the light shielding plate. Transparent member. The polarized light irradiation device according to item 2 of the scope of patent application, wherein an air supply and exhaust portion is formed in a plurality of portions of the light shielding plate. A polarized light irradiation device comprising: a light source that emits light; a first polarizing element that transmits polarized light having a polarization axis parallel to a predetermined reference direction among light emitted from the light source; and an absorption type A polarizing element, so that the light transmitted through the first polarizing element is The polarized light whose polarization direction is parallel to the predetermined reference direction is transmitted first. The polarized light irradiation device according to item 4 of the scope of patent application, wherein a filter is provided between the light source and the first polarizing element. The polarized light irradiation device according to item 4 or item 5 of the scope of the patent application, wherein the light source is a mercury lamp or a metal halide lamp.