JP2018072488A - Projection device, automobile and polarizing plate for projection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection device capable of easily diminishing sunlight reversely progressing in a light path of projection light.SOLUTION: A projection device 10 includes: a display 1 configured to emit projection light P; a reflector 2 configured to reflect the projection light P; and a housing 3 having an opening 31 and accommodating the display 1 and the reflector 2 therein. A polarizer 6 including an aromatic disazo compound is arranged on a light path of the projection light P, in a location from emission by the display 1 to reflection by the reflector 2, passing the opening 31 to reach an outside of the housing 3.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a projection device and the like.

2. Description of the Related Art Conventionally, display devices having a reflector that does not transmit light such as a screen and a projection device such as a projector are known. The projection light is emitted from the projection device to the reflector, and the projection light is reflected on the reflector, whereby the observer can visually recognize the image.
In recent years, a display device using a translucent reflector having translucency has been developed by improving a conventional display device, and is generally called a head-up display. For example, a head-up display that displays an image by projecting light emitted from a projection device onto a windshield of an automobile, which is a translucent reflector, is known.
The translucent reflector not only reflects light emitted from the projection device but also transmits light from the outside. Therefore, the observer can not only visually recognize the image projected on the translucent reflector, but also see the situation on the opposite side of the translucent reflector (that is, the side where the observer is not present with respect to the translucent reflector). Can do.
Therefore, when a head-up display is mounted on a car, the driver of the car, who is an observer, looks at the operation information such as the position coordinates and speedometer projected on the windshield, which is a translucent reflector, and moves the windshield. You can see the situation outside the car through the watermark. Therefore, the driver can obtain the operation information without driving a line of sight from the traveling direction while driving the automobile.

As shown in FIG. 12, normally, a projection apparatus 10A for head-up display (hereinafter simply referred to as “projection apparatus”) includes a display 1A that emits projection light, and a reflector 2A that reflects the projection light. And a housing 3A for housing the display 1A and the reflector 2A.
The housing 3A has an opening 31A. The projection light P emitted from the display device 1A is reflected by the reflector 2A, emitted to the outside of the housing through the opening 31A of the housing 3A, and then projected onto a translucent reflector (not shown). Is done. The opening 31A of the housing 3A is covered with a cover member 4A so that dust does not enter the housing 3A.
When such a projection apparatus 10A is mounted on an automobile, the installation location is often a portion that is easily exposed to sunlight, such as a dashboard. Sunlight passes through the cover member 4A as well as the outer surface of the housing 3A and enters the housing 3A. Therefore, the projection apparatus 10A is heated by sunlight from both inside and outside, so that the temperature rises easily. However, the constituent members of the projection apparatus 10A often do not have sufficient heat resistance and are likely to deteriorate gradually.
In particular, of the constituent members of the projection apparatus 10A, the display 1A including an electronic device is easily deteriorated by heat. Part of the sunlight S that has entered the housing 3A is reflected by the reflector 2A, and the reflected sunlight S enters the display. That is, a part of the sunlight travels backward in the optical path of the projection light P, and the display 1A is irradiated with the backward sunlight S. For this reason, the display 1A has a problem that the temperature tends to rise, and therefore, it tends to break down.
In FIG. 12, for the sake of convenience, the optical path of the projection light P and the optical path of the sunlight S that reverses this optical path are depicted in a shifted manner (the same applies to other figures). Further, illustration of the sunlight that randomly enters the inside of the housing 3A without reversing the optical path of the projection light P is omitted (the same applies to other figures except for FIG. 10).

In order to solve such a problem, Patent Document 1 discloses a projection apparatus including a plane mirror that transmits only infrared rays and reflects visible rays and ultraviolet rays (hereinafter referred to as “cold mirror”) ( (See FIG. 13).
In the projection apparatus 10B of Patent Document 1, the sunlight S that travels back along the optical path of the projection light P is reflected by the reflector 2B and then enters the cold mirror 5B before reaching the display 1B. The cold mirror 5B has a property of transmitting infrared rays. Accordingly, the infrared rays are attenuated from the sunlight S that travels back along the optical path of the projection light P and is incident on the cold mirror 5B, and the sunlight S whose infrared rays have been attenuated is incident on the display 1B. It becomes difficult. In addition, in FIG. 13, the thickness of the black arrow which shows sunlight S represents the light quantity of sunlight S (this is the same also about another figure).
However, when the cold mirror 5B is provided, it must be adjusted so that the projection light P enters the reflector 2B through the cold mirror 5B at an appropriate angle, and such adjustment is very complicated. Therefore, there is a demand for a projection apparatus that can more easily attenuate the sunlight S that travels backward through the optical path of the projection light P.

JP 2004-347633 A

  An object of the present invention is to provide a projection apparatus that can easily reduce sunlight that reverses the optical path of projection light.

  The projection device of the present invention includes a display that emits projection light, a reflector that reflects the projection light, and a housing that has an opening and accommodates the display and the reflector inside. On the optical path of the projection light, the general formula (1), which will be described later, is from the emission from the display device to the outside of the housing through reflection by the reflector and passing through the opening. The polarizer containing the aromatic disazo compound represented by these is provided.

Preferably, the opening of the housing is covered with a cover member that allows projection light to pass therethrough.
Preferably, the polarizer is provided on at least one member selected from the indicator, the reflector, and the cover member. More preferably, the polarizer is provided on the cover member.
Preferably, the cover member includes at least one resin selected from polycarbonate resin, acrylic resin, styrene resin, olefin resin, vinyl chloride resin, amide resin, and imide resin. .
Preferably, the cover member has a thickness of 10 μm to 1000 μm.

  According to another aspect of the present invention, an automobile equipped with the projection apparatus of the present invention is provided.

  Moreover, according to another situation of this invention, it has a board | substrate and a polarizer, The said polarizer contains the aromatic disazo compound represented by General formula (1) mentioned later, Polarized light for projection apparatuses A board is provided.

  In the projection device of the present invention, a polarizer including an aromatic disazo compound represented by the general formula (1) is provided on the optical path of the projection light. This polarizer reverses the optical path of the projection light and part of the sunlight incident on the display device is diminished, and as a result, it is difficult for the display device to rise in temperature.

FIG. 2 is a schematic cross-sectional view showing the projection apparatus according to the first embodiment. FIG. 3 is a schematic sectional view showing a display device included in the projection apparatus. (A) is a general | schematic side view which shows the reflector which the same projection apparatus has, (b) is a general | schematic front view which looked at the reflector of (a) from the III (b) direction. The side view which shows the polarizing plate which the same projection apparatus has. FIG. 6 is a schematic sectional view showing a projection apparatus according to a second embodiment. FIG. 10 is a schematic sectional view showing a projection apparatus according to a third embodiment. FIG. 10 is a schematic sectional view showing a projection apparatus according to a fourth embodiment. FIG. 10 is a schematic cross-sectional view showing a display device included in a projection apparatus according to a fifth embodiment. FIG. 10 is a schematic side view showing a reflector included in a projection apparatus according to a sixth embodiment. FIG. 10 is a schematic cross-sectional view showing a cover member included in a projection apparatus according to a seventh embodiment. The side view which shows the cut piece mounted in the horizontal surface. FIG. 10 is a schematic sectional view showing a conventional projection apparatus. FIG. 10 is a schematic sectional view showing a conventional projection apparatus.

Hereinafter, the projection apparatus according to the first embodiment of the present invention will be described with reference to the drawings, and then the projection apparatuses according to the second to seventh embodiments will be described. About the projection apparatus which concerns on 2nd thru | or 7th embodiment, a difference with 1st Embodiment is mainly demonstrated, and description is abbreviate | omitted suitably about a common point. It should be noted that dimensions such as thickness and size in each figure are different from actual ones.
In this specification, for the sake of convenience, the latter is referred to as a “polarizing film” in order to distinguish between a polarizer used for solar light attenuation and a polarizer (polarizer used for generating projection light) included in a liquid crystal display element of a display. ".
In the present specification, a numerical range of “to” means a numerical range including numerical values before and after “to” as a lower limit value and an upper limit value. When a plurality of lower limit values and a plurality of upper limit values are separately described, arbitrary lower limit values and upper limit values can be selected and connected by “˜”.

[First Embodiment]
FIG. 1 shows a projection apparatus 10 according to the first embodiment of the present invention, and FIGS. 2 to 4 show constituent members of the projection apparatus 10 according to this embodiment.
The projection device 10 includes a display 1 that emits projection light, and a reflector 2 that reflects the projection light P emitted from the display 1. Both the display 1 and the reflector 2 are accommodated in a housing 3 having an opening 31.
In the present embodiment, the opening 31 of the housing 3 is covered with the cover member 4 so that dust does not enter the inside of the housing 3. The cover member 4 is a member having translucency. Therefore, the projection light P reflected by the reflector 2 passes through the cover member 4, that is, passes through the opening 31 via the cover member 4 and is emitted to the outside of the housing 3. The projection light P emitted to the outside of the housing 3 is projected onto a translucent reflector (not shown) such as a windshield of an automobile, and as a result, an observer can visually recognize an image.
As described above, the projection light P emitted from the display device 1 has an optical path that reaches the outside of the housing 3 through reflection by the reflector 2 and transmission through the cover member 4. In the present invention, a polarizer 6 including an aromatic disazo compound represented by the following general formula (1) is provided on the optical path of the projection light P. In the present embodiment, a polarizing plate 8 including a polarizer 6 is disposed between the display 1 and the reflector 2 on the optical path of the projection light P.
Hereinafter, after describing each component which the projector 10 which concerns on 1st Embodiment of this invention has in detail, the preparation methods of the polarizing plate 8 are demonstrated.

<Display>
A display 1 shown in FIG. 2 is a device that emits projection light P projected onto a light-transmissive reflector.
In the present invention, a polarizing plate 8 including a polarizer 6 is provided on the optical path of the projection light P. Therefore, the projection light P emitted from the display device 1 includes linearly polarized light that can be transmitted through the polarizer 6 provided on the optical path, and preferably includes only linearly polarized light that can be transmitted through the polarizer 6. . The linearly polarized light that can be transmitted through the polarizer 6 is light having a vibration direction parallel to the direction in which the transmission axis of the polarizer 6 extends (transmission axis direction).
The display 1 is not particularly limited as long as it can emit the projection light P including such linearly polarized light. For example, the configuration shown in FIG. 2 can be adopted.
As shown in FIG. 2, the display 1 includes a light source 11, a light adjustment member group 12, a liquid crystal display element 13, and a cylindrical holding member 14 that stores these.
In the present embodiment, the light source 11, the light adjustment member group 12, and the liquid crystal display element from the first end to the second end (end opposite to the first end) in the longitudinal direction of the cylindrical holding member. 13 are arranged in this order.

  The light source 11 is a member that emits light that is a source for generating the projection light P. In the present embodiment, the light source includes a plurality of light emitting elements 111 and a printed circuit board 112. An opening (hereinafter referred to as “first opening”) at the first end of the holding member 14 is closed by the printed circuit board 112. The light emitting element 111 is disposed on the printed circuit board 112, and power is supplied through the printed circuit board 112. For example, a light emitting diode (LED) is used as the light emitting element 111. By supplying electric power to the light emitting diode via the printed circuit board 112, light is emitted from the light emitting diode toward the light adjustment member group 12.

The light adjusting member group 12 makes the light emitted from the light source 11 uniform, condenses the light, and toward the opening (hereinafter referred to as “second opening”) side of the second end of the holding member 14. That is, it is an apparatus that emits light to the liquid crystal display element 13. In the present embodiment, the light adjustment member group 12 is configured by a diffusion plate 121 and a condenser lens 122.
The diffusion plate 121 is a member that uniformizes the light emitted from the light source 11 toward the liquid crystal display element 13. As the diffusing plate 121, a translucent plate-like member having at least one surface subjected to uneven processing can be used. In this embodiment, as shown in FIG. 2, two diffusion plates 121 (a first diffusion plate 121a located on the first opening side of the holding member 14 and a second diffusion plate 121b located on the second opening side). Is used.
The condensing lens 122 is a member that condenses light and emits it toward the liquid crystal display element 13. In the present embodiment, the condensing lens 122 is interposed between the first diffusion plate 121a and the second diffusion plate 121b. Two are provided. Of the two condenser lenses 122, the first condenser lens 122a is located on the first diffuser plate 121a side, and the second condenser lens 122b is located on the second diffuser board 121b side.

The liquid crystal display element 13 is a member that generates the projection light P from the light emitted from the light adjustment member group 12. The liquid crystal display element 13 includes a liquid crystal cell 131 in which liquid crystal is sealed between a pair of transparent substrates provided with transparent electrodes, and two polarizing films 132a and 132b provided on both sides of the liquid crystal cell 131, respectively. The first polarizing film 132a is disposed on the surface of the liquid crystal cell 131 on the light adjusting member group 12 side, and the second polarizing film 132b is disposed on the opposite surface.
The light emitted from the light adjusting member group 12 passes through the liquid crystal display element 13 and becomes projection light including display information displayed on the translucent reflector. Specifically, the liquid crystal display element 131 is connected to a control means (not shown) such as a microcomputer having an arithmetic processing unit and a storage unit, and the liquid crystal display element 13 is controlled by the control by the control means. Projection light P including display information is generated from the transmitted light. Since the liquid crystal display element 13 includes the polarizing film 132, the projection light P is linearly polarized light.

The holding member 14 fixes the light source 11, the light adjustment member group 12, and the liquid crystal display element 13 at fixed positions inside the housing 3, and displays the display 1 until the projection light P is generated by the liquid crystal display element 13. It is a cylindrical member that prevents light from leaking out. In the present embodiment, the first opening of the holding member 14 is closed by the printed circuit board 112 of the light source 11, but the second opening existing on the opposite side is open toward the reflector 2. .
The holding member 14 may be a part of the housing 3 or a member independent of the housing 3. Considering the case where the arrangement of the display device 1 is changed inside the housing 3, the holding member 14 is preferably a member independent of the housing 3. When the holding member 14 is a member independent of the housing 3, the holding member 14 is fixed to the inner wall of the housing 3 by any fixing means (for example, a screw).

<Reflector>
The reflector 2 shown in FIGS. 3A and 3B is a member that reflects the projection light P emitted from the display 1 toward the opening 31 of the housing 3. The projection light P emitted from the display 1 by the reflector 2 is reflected toward the opening 31 of the housing 3, and the projection light P transmitted through the cover member 4 provided in the opening 31 of the housing 3 is transmitted. Projected onto a light reflector.
The reflector 2 includes, for example, a mirror part 21 and a mirror holder 22 that fixes the mirror part 21 at a fixed position inside the housing 3. The mirror part 31 may be a plane mirror or a concave mirror, but preferably a concave mirror is used as shown in FIG. By using the concave mirror, the image projected on the translucent reflector can be enlarged and displayed. The radius of curvature of the concave mirror is not particularly limited, and can be appropriately set in consideration of the size of the image projected on the translucent reflector.

The mirror holder 22 may hold the mirror unit 21 in a fixed manner so that the angle of the mirror unit 21 does not change, but preferably holds the mirror unit 21 so that the angle of the mirror unit 21 can be adjusted.
When the projector 10 is mounted on an automobile, the seat height varies depending on the driver of the automobile. Therefore, if the position of the projection light P projected on the translucent reflector (the windshield) is constant, it is projected for a certain driver. However, it may be difficult for other drivers to see the projected image. In this respect, by making the angle of the mirror part 21 adjustable, the position of the image projected on the translucent reflector can be changed, and display suitable for the driver is possible.
In the present embodiment, a mirror holder 22 capable of adjusting the angle of the mirror unit 21 is used. Specifically, the mirror holder 22 includes a shaft 221 whose peripheral surface is connected to the back surface of the mirror unit 21, and a control unit 222 connected to the end of the shaft 221. Since the angle of the mirror unit 21 changes following the rotation of the shaft 221, the angle of the mirror unit 21 can be indirectly adjusted by controlling the rotation of the shaft 221 by the control unit 222. The control unit 222 is connected to, for example, an instrument panel of an automobile, and the driver can change the angle of the mirror unit 21 via the instrument panel.

<Case>
The housing 3 shown in FIG. 1 is a box-shaped member having an internal space that can accommodate the display 1 and the reflector 2.
The housing 3 has an opening 31, and the projection light P emitted from the display device 1 is emitted to the outside of the housing 3 through the opening 31. In the present embodiment, the housing 3 has a light shielding wall 32 inside thereof. The light shielding wall 32 is a part of the inner wall of the housing 3. The light shielding wall 32 is a plate-like portion protruding so as not to interfere with the optical path of the projection light P and to be positioned between the opening 31 and the display 1. The light shielding wall 32 prevents sunlight incident from the opening 31 (sunlight different from sunlight S that reverses the optical path of the projection light P) from directly irradiating the display 1. Temperature can be prevented more effectively. The light shielding wall 32 may be a plate-like member independent of the housing 3.

The material for forming the housing 3 is not particularly limited, but it is preferable to use a material that is not easily heated by irradiation with sunlight and is easy to mold. Examples of such materials include acrylic resins, epoxy resins, polyester resins, urethane resins, polyolefin resins, fluorine resins, phenoxy resins, and the like. These resins can be used alone or in combination of two or more.
Note that when the projection apparatus 10 is mounted on an automobile, the housing 3 may be a part of the automobile or a member independent of the automobile. The case where the housing 3 is a part of an automobile is, for example, the case where the dashboard itself is used as the housing 3 of the projection apparatus 10 of the present invention.

The width of the opening 31 is not particularly limited. If the opening 31 of the housing 3 is widened, the opening can be easily changed by changing the angle of the reflector 2 even when the arrangement of the display 1 and the reflector 2 is changed inside the housing 3. Although the projection light P can be emitted from 31, sunlight is more likely to enter the interior of the housing 3. On the other hand, if the opening 31 of the housing 3 is narrowed, it is difficult for sunlight to enter the inside of the housing 3, but there is a concern that the change in the arrangement of the display 1 and the reflector 2 may be limited.
In view of these, the area of the opening 31 in plan view (when viewed dotted arrow projection apparatus 10 from the direction of FIG. 1) is preferably 10cm ² ~200cm ^2, more preferably, 20 cm ² ~ a 100 cm ^2, particularly preferably from 20cm ² ~80cm ^2.

<Cover member>
The cover member 4 is a plate-like member that covers the opening 31 of the housing 3 so that dust does not enter the inside of the housing 3. The cover member 4 is transparent. Therefore, the projection light P reflected from the reflector 2 passes through the cover member 4 and is emitted to the outside of the housing 3. The term “transparent” means having a property of transmitting visible light having a wavelength of 360 nm to 830 nm. Transparency does not substantially absorb visible light, transmits light of all wavelengths in the visible light range (colorless and transparent), and absorbs light of some wavelengths in the visible light range, and the wavelength Including the case of transmitting light other than (transparent colored). The cover member 4 is preferably colorless and transparent. The total light transmittance of the cover member is 50% or more, preferably 70% or more, and more preferably 90% or more. The total light transmittance is a value measured according to JIS K7375.

The surface shape of the cover member 4 can be appropriately changed according to the opening 31 of the housing 3. For example, as for the cover member 4, the part which covers the opening part 31 may be comprised only from the plane or only the curved surface, and the part which covers the opening part 31 may be comprised from several planes and / or several curved surfaces. Good. Usually, the surface shape of the cover member 4 covering the opening 31 is composed of only a flat surface or only a curved surface. In the present embodiment, as shown in FIG. 1, a cover member 4 is used in which the portion covering the opening 31 is composed only of a curved surface.
The thickness of the cover member 4 is not particularly limited. However, if the cover member 4 is too thick, the transmittance of the projection light P transmitted through the cover member 4 is reduced (the light loss of the projection light P increases), and there is a possibility that a double image is generated. is there.
Considering these, the upper limit value of the thickness of the cover member 4 is 1000 μm. The lower limit value of the thickness of the cover member is usually 10 μm.

  The material of the cover member is not particularly limited as long as it is transparent, and resin, glass or the like can be used. Examples of the transparent resin include ester resins such as polyethylene terephthalate and polyethylene naphthalate; cellulose resins such as diacetyl cellulose and triacetyl cellulose; polycarbonate resins such as bisphenol A polycarbonate; acrylic resins such as polymethyl methacrylate; Acrylic resins such as lactone-modified acrylic resins; styrene resins such as polystyrene and acrylonitrile / styrene copolymers; polyolefins having polyethylene, polypropylene, cyclic structure or norbornene structure, and olefin resins such as ethylene / propylene copolymers; Vinyl chloride resin; Amide resin such as aromatic polyamide; Imido resin; Sulfone resin; Polyethersulfone resin; Polyetheretherketone resin; Phenylene sulfide resins; vinyl alcohol-based resin: vinylidene chloride resin, vinyl butyral resins; arylate resin; polyoxymethylene-based resin, epoxy-based resin; and the like. These resins can be used alone or in combination of two or more.

<Polarizing plate>
In the present invention, a polarizer 6 including an aromatic disazo compound represented by the following general formula (1) is provided on the optical path of the projection light P. In the present embodiment, a polarizing plate 8 including the polarizer 6 is provided. Is provided.
As shown in FIG. 1, the optical path of the projection light P reaches the outside of the housing 3 through emission by the display device 1, reflection by the reflector 2, and passage through the opening 31. In the present embodiment, since the cover member 4 is provided in the opening 31, the projection light P passes through the opening 31 by passing through the cover member 4 and reaches the outside of the housing 3.
More specifically, in the present embodiment, since the projection light P is generated by the liquid crystal display element 13 provided in the display, the optical path of the projection light P is the surface of the liquid crystal display element 13 closest to the reflector 2 (FIG. 2). The surface of the polarizing film 132b in FIG. The projection light P generated by the liquid crystal display element 13 reaches the cover member 4 via the reflector 2, then passes through the cover member 4 and reaches the space outside the housing 3.
In the present embodiment, a polarizing plate 8 is provided between the display 1 and the reflector 2 on the optical path of the projection light P from the surface of the liquid crystal display element 13 to the space outside the housing 3. Yes.

As shown in FIG. 4, the polarizing plate 8 includes a substrate 7 and a polarizer 6. The polarizing plate 8 is supported by an appropriate support member (not shown) fixed to the inner wall of the housing 3. The substrate 7 is a member laminated on the polarizer 6 that is a thin film. The substrate 7 is used for protecting the polarizer 6.
The material of the substrate 7 is not particularly limited, but preferably a transparent material having substantially optical isotropy (that is, having substantially no optical anisotropy) is used. Examples of such a material include glass, quartz, and resin.
If the substrate 7 has optical anisotropy, the phase of the projection light P may be disturbed by the substrate 7. When the polarizing plate 8 is arranged so that the projection light P is transmitted through the substrate 7 before the polarizer 6, the phase of the projection light P is disturbed by the substrate 7, and the projection light P is difficult to transmit through the polarizer 6. There is a fear. Considering the possibility that the phase of the projection light P is disturbed by the substrate 7, it is preferable to dispose the polarizing plate 8 so that the projection light P passes through the polarizer 6 before the substrate 7 as shown in FIG. 4. . In other words, the polarizing plate 8 is preferably provided such that the substrate 7 is disposed on the reflector 2 side and the polarizer 6 is disposed on the display 1 side.

Here, “the substrate 7 is substantially optically isotropic” means not only when the refractive index ellipsoid of the substrate 7 is nx = nz = ny but also when nx≈nz≈ny. including.
Specifically, including the case where the absolute value of the in-plane birefringence index Δnxy (nx−ny) of the substrate 7 and the absolute value of the thickness direction birefringence index Δnxz (nx−nz) are 0.0005 or less, Preferably it is 0.0001 or less, More preferably, it is 0.00005 or less.
In the present specification, “nx” represents the refractive index in the direction (X-axis direction) in which the in-plane refractive index is maximum with respect to 23 ° C. and a wavelength of 590 nm. Represents the refractive index in the direction (Y-axis direction) orthogonal to the X-axis direction within the same plane, and the “nz” is the refraction in the direction (thickness direction) orthogonal to the X-axis direction and the Y-axis direction. Represents a rate.
The thickness of the substrate 7 is not particularly limited. However, if the substrate 7 is too thin, the polarizer 6 may not be sufficiently protected. If the substrate 7 is too thick, there is a possibility that the light loss of the projection light P that passes through the polarizing plate 8 increases.
Considering these, the lower limit value of the thickness of the substrate 7 is preferably 100 μm, more preferably 200 μm, and particularly preferably 300 μm. Further, the upper limit value of the thickness of the substrate 7 is preferably 700 μm, more preferably 600 μm, and particularly preferably 500 μm.

  The polarizer 6 is a member that extracts linearly polarized light having a specific vibration direction from sunlight (non-polarized light). In other words, it is a member that absorbs sunlight other than linearly polarized light having a specific vibration direction. In the present invention, a polarizer 6 containing an aromatic disazo compound represented by the following general formula (1) is used.

In the general formula (1), Q ¹ represents a substituted or unsubstituted aryl group, Q ² represents a substituted or unsubstituted arylene group, and R ¹ independently represents a hydrogen atom, substituted or unsubstituted An alkyl group, a substituted or unsubstituted acetyl group, a substituted or unsubstituted benzoyl group, a substituted or unsubstituted phenyl group, M represents a counter ion, m represents an integer of 0 to 2, n Represents an integer of 0-6. However, at least one of m and n is not 0 but 1 ≦ m + n ≦ 6. When m is 2, each R ¹ is the same or different.
OH, (NHR ¹ ) _m , and (SO ₃ M) _n represented by the general formula (1) may be bonded to any of the seven substitution sites of the naphthyl ring.
In the present specification, “substituted or unsubstituted” means “substituted with a substituent or not substituted with a substituent”.

  The bonding position of the naphthyl group and the azo group (—N═N—) of the general formula (1) is not particularly limited. The naphthyl group refers to a naphthyl group represented on the right side in the formula (1). Preferably, the naphthyl group and the azo group are bonded at the 1-position or 2-position of the naphthyl group.

When the alkyl group, acetyl group, benzoyl group, or phenyl group of R ^{1 in} the general formula (1) has a substituent, examples of the substituent include each substituent exemplified in the following aryl group or arylene group. It is done.
R ¹ is preferably a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted acetyl group, and more preferably a hydrogen atom.
Examples of the substituted or unsubstituted alkyl group include substituted or unsubstituted alkyl groups having 1 to 6 carbon atoms.

M (counter ion) in the general formula (1) is preferably a hydrogen ion; an alkali metal ion such as Li, Na, K, or Cs; an alkaline earth metal ion such as Ca, Sr, or Ba; An ammonium ion which may be substituted with an alkyl group or a hydroxyalkyl group; a salt of an organic amine and the like. Examples of the metal ions include Ni ⁺ , Fe ³⁺ , Cu ²⁺ , Ag ⁺ , Zn ²⁺ , Al ³⁺ , Pd ²⁺ , Cd ²⁺ , Sn ²⁺ , Co ²⁺ , Mn ²⁺ , and Ce ³⁺ . Examples of the organic amine include an alkylamine having 1 to 6 carbon atoms, an alkylamine having 1 to 6 carbon atoms having a hydroxyl group, and an alkylamine having 1 to 6 carbon atoms having a carboxyl group. In the general formula (1), when there are two or more SO ₃ Ms, each M may be the same or different. In the general formula (1), when M of SO ₃ M is a cation having a valence of 2 or more, it is bonded to SO ₃ ^— of the azo compound of the other general formula (1) adjacent to the supramolecular group. A coalescence can be formed.

M in the general formula (1) is preferably 1. Further, n in the general formula (1) is preferably 1 or 2.
Specific examples of the naphthyl group of the general formula (1) include the following formulas (a) to (l). R ¹ and M in the formulas (a) to (l) are the same as those in the general formula (1).

In the general formula (1), examples of the aryl group represented by Q ¹ include a condensed ring group in which two or more benzene rings are condensed, such as a naphthyl group, in addition to a phenyl group.
Examples of the arylene group represented by Q ² include a phenylene group and a condensed ring group in which two or more benzene rings are condensed, such as a naphthylene group.

The aryl group of Q ¹ or the arylene group of Q ² may have a substituent, or may not have a substituent. Regardless of whether the aryl group or arylene group is substituted or unsubstituted, the aromatic disazo compound of the general formula (1) having a polar group is excellent in solubility in an aqueous solvent.

When the aryl group or arylene group has a substituent, examples of the substituent include an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylamino group having 1 to 6 carbon atoms, and phenyl. An amino group, an acylamino group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms such as a dihydroxypropyl group, a carboxyl group such as a COOM group, a sulfonic acid group such as an SO ₃ M group, a hydroxyl group, a cyano group, and a nitro group Group, amino group, halogeno group and the like. Preferably, the substituent is one selected from an alkoxy group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, a carboxyl group, a sulfonic acid group, and a nitro group. An aromatic disazo compound having such a substituent is particularly excellent in water solubility. These substituents may be substituted alone or in combination of two or more. Moreover, the said substituent may be substituted by arbitrary ratios.

Q ^{1 in the} general formula (1) is preferably a substituted or unsubstituted phenyl group, and more preferably a phenyl group having the substituent.
Q ² is preferably a substituted or unsubstituted naphthylene group, more preferably a naphthylene group having the substituent, and particularly preferably a 1,4-naphthylene group having the substituent.

An aromatic disazo compound in which Q ^{1 in the} general formula (1) is a substituted or unsubstituted phenyl group and Q ² is a substituted or unsubstituted 1,4-naphthylene group is represented by the following general formula (2). expressed.

In the general formula (2), R ¹ , M, m and n are the same as those in the general formula (1).
In General formula (2), A and B represent a substituent, and a and b represent the number of substitutions. A and B are each independently an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylamino group having 1 to 6 carbon atoms, a phenylamino group, or an acylamino having 1 to 6 carbon atoms. Group, a hydroxyalkyl group having 1 to 6 carbon atoms such as dihydroxypropyl group, a carboxyl group such as COOM group, a sulfonic acid group such as SO ₃ M group, a hydroxyl group, a cyano group, a nitro group, an amino group, and a halogeno group. The a is an integer of 0 to 5, and the b is an integer of 0 to 4. However, at least one of a and b is not 0. When the a is 2 or more, the substituents A may be the same or different. When b is 2 or more, the substituents B may be the same or different.

  Among the aromatic disazo compounds included in the general formula (2), it is preferable to use an aromatic disazo compound represented by the following general formula (3). In the aromatic disazo compound of the general formula (3), the substituent A is bonded to the para position on the basis of the azo group (—N═N—). Furthermore, in the aromatic disazo compound of the general formula (3), the OH group of the naphthyl group is bonded to the position (ortho position) adjacent to the azo group. If the aromatic disazo compound of the general formula (3) is used, it is possible to easily form the polarizer 6 that is not easily contracted by heating.

In the general formula (3), R ¹ , M, m and n are the same as those in the general formula (1), and A is the same as that in the general formula (2).
In General formula (3), p represents the integer of 0-4. The p is preferably 1 or 2, and more preferably 1.

Aromatic disazo compounds represented by the above general formulas (1) to (3) are, for example, “Theoretical Manufacturing Dye Chemistry (5th Edition)” written by Yutaka Hosoda (published on July 15, 1968, Gihodo, pages 135-152). Page).
For example, the aromatic disazo compound of the general formula (3) is obtained by diazotizing and coupling an aniline derivative and a naphthalenesulfonic acid derivative to obtain a monoazo compound, diazotizing the monoazo compound, It can be synthesized by a coupling reaction with an amino-8-naphtholsulfonic acid derivative.

  The thickness of the polarizer 6 used in the present invention is not particularly limited. However, if the polarizer 6 is too thin, there is a possibility that the sunlight that reverses the optical path of the projection light cannot be sufficiently reduced. If the polarizer 6 is too thick, the projection light may be absorbed. Considering these, the lower limit value of the thickness of the polarizer 6 is preferably 100 nm, more preferably 200 nm, and particularly preferably 300 nm. The upper limit of the thickness of the polarizer 6 is preferably 1000 nm, more preferably 700 nm, and particularly preferably 500 nm.

<Preparation method of polarizing plate>
The polarizing plate 8 can be manufactured by the following process B and process C, for example. As needed, the process A may be performed before the process B and the process D may be performed after the process C.
Step A: A step of performing an alignment treatment on the surface of the substrate 7.
Process B: The process of apply | coating the coating liquid containing the aromatic disazo compound represented by the said General formula (1) to the surface of the board | substrate 7, and forming a coating film.
Process C: The process of drying a coating film and forming the polarizer 6 which is a dry coating film.
Step D: A step of applying water resistance treatment to the surface of the polarizer 6 obtained in Step C.

(Process A)
Step A is a step of applying an alignment regulating force to the surface of the substrate 7 by performing an alignment process on the surface of the substrate 7. When the substrate 7 having the orientation regulating force is used in advance, it is not necessary to perform the step A.
For example, (a) a method in which the surface of the substrate 7 is rubbed, (b) a film of polyimide or the like is formed on the surface of the film, and the surface of the film is rubbed to align the alignment film. And (c) a method of forming a film made of a photoreactive compound on the surface of the film and irradiating the film with light to form an alignment film.
When the methods (b) and (c) are used, a polarizing plate having an alignment film between the substrate 7 and the polarizer 6 is produced.

(Process B)
Step B is a step of forming a coating film using a coating liquid.
The coating liquid contains the aromatic disazo compound and a solvent for dissolving or dispersing the aromatic disazo compound. The coating liquid is obtained by dissolving or dispersing the aromatic disazo compound in a solvent. In addition, you may add other polymers other than the said aromatic disazo compound, and / or an additive to the said solvent as needed.

  The solvent for dissolving or dispersing the aromatic disazo compound is not particularly limited, and a conventionally known solvent can be used, but an aqueous solvent is preferable. Examples of the aqueous solvent include water, a hydrophilic solvent, a mixed solvent of water and a hydrophilic solvent, and the like. The hydrophilic solvent is a solvent that dissolves substantially uniformly in water. Examples of the hydrophilic solvent include alcohols such as methanol and isopropyl alcohol; glycols such as ethylene glycol; cellosolves such as methyl cellosolve and ethyl cellosolve; ketones such as acetone and methylethylketone; esters such as ethyl acetate; Is mentioned. As the aqueous solvent, water or a mixed solvent of water and a hydrophilic solvent is preferably used.

The aromatic disazo compound represented by the general formula (1) used in the present invention is an organic compound having lyotropic liquid crystallinity. Therefore, the coating liquid exhibits a lyotropic liquid crystal phase by changing the liquid temperature, the concentration of the aromatic disazo compound, and the like. The lyotropic liquid crystal phase is generated when an aromatic disazo compound forms a supramolecular aggregate in a liquid. The lyotropic liquid crystal phase can be confirmed and identified by an optical pattern observed with a polarizing microscope.
The supramolecular aggregate is one large complex formed by bonding a plurality of aromatic disazo compounds by hydrogen bonds or the like.

The concentration of the aromatic disazo compound in the coating liquid is preferably adjusted so that it exhibits a liquid crystal phase. The concentration of the aromatic disazo compound in the coating liquid is usually 0.05% to 50% by weight, preferably 0.5% to 40% by weight, more preferably 1% to 10% by weight. is there.
The coating solution is adjusted to an appropriate pH. The pH of the coating solution is preferably about pH 2 to 10, more preferably about pH 6 to 8.
Furthermore, the temperature of the coating liquid is preferably adjusted to 10 ° C to 40 ° C, more preferably 15 ° C to 30 ° C.

A coating film is formed by applying the coating liquid on the substrate 7. In the coating film, the aromatic disazo compound is oriented in a predetermined direction by the orientation regulating force of the substrate 7.
The coating method of the coating liquid is not particularly limited, and for example, a coating method using a conventionally known coater can be adopted. Examples of the coater include a bar coater, a roll coater, a spin coater, a comma coater, a gravure coater, an air knife coater, and a die coater.

(Process C)
Step C is a step of forming a polarizer 6 that is a dry coating film. By forming the polarizer 6 that is a dry coating film on the substrate 7, the polarizing plate 8 having the substrate 7 and the polarizer 6 is obtained.
By drying the coating film obtained in step B, the solvent contained in the coating film is volatilized, and a dry coating film (polarizer 6) containing a solid aromatic disazo compound is formed. In the polarizer 6, the orientation of the aromatic disazo compound is fixed while forming a supramolecular aggregate.
The drying method of a coating film is not specifically limited, Natural drying and forced drying can be implemented. Examples of forced drying include reduced-pressure drying, heat drying, and reduced-pressure heat drying. Preferably, natural drying is used.
The drying time of the coating film can be appropriately selected depending on the drying temperature and the type of solvent. For example, in the case of natural drying, the drying time is preferably 1 second to 120 minutes, more preferably 10 seconds to 5 minutes.
Moreover, although drying temperature is not specifically limited, Preferably it is 10 to 100 degreeC, More preferably, it is 10 to 90 degreeC, Most preferably, it is 10 to 80 degreeC.
The drying temperature means not the surface temperature or the internal temperature of the coating film but the temperature of the atmosphere in which the coating film is dried.

(Process D)
Step D is a step of imparting water resistance to the polarizer 6 by bringing the water-resistant treatment solution into contact with the polarizer 6.
The method for bringing the polarizer 6 into contact with the water-resistant treatment liquid is not particularly limited. As a contact method, (a) a water-resistant treatment liquid is applied to the surface of the polarizing plate 8 (polarizer 6), (b) the polarizing plate 8 is immersed in a bath filled with the water-resistant treatment liquid, (c ) A method of allowing the polarizing plate 8 to pass through a bath filled with a water-resistant treatment solution. The application of the water-resistant treatment liquid (a) can be performed using an appropriate coater or spray.

The water-resistant treatment liquid is not particularly limited, and a conventionally known one can be used. The water-resistant treatment liquid includes, for example, a crosslinking agent having a function of crosslinking the organic dye and a solvent that dissolves or disperses the crosslinking agent.
Examples of the crosslinking agent include organic nitrogen compounds, and examples of the solvent include aqueous solvents.
As the organic nitrogen compound, an acyclic organic nitrogen compound having two or more cationic groups (preferably a cationic group containing a nitrogen atom) in the molecule is preferably used. Examples of the acyclic organic nitrogen compound (acyclic aliphatic nitrogen compound) include aliphatic diamines such as alkylene diamines or salts thereof; aliphatic triamines such as alkylene triamines or salts thereof; fats such as alkylene tetraamines. Aliphatic tetraamines or salts thereof; aliphatic pentaamines or salts thereof such as alkylene pentaamines; aliphatic ether diamines or salts thereof such as alkylene ether diamines.
As said aqueous solvent, what was illustrated in the column of the said process B can be used.

The concentration of the crosslinking agent in the water-resistant treatment liquid is preferably 1% by mass to 50% by mass, and more preferably 5% by mass to 30% by mass.
When the polarizer 6 is brought into contact with the water-resistant treatment solution, the organic dyes inside the polarizer 6 are cross-linked via a cross-linking agent. By the cross-linking, the polarizer 6 having excellent water resistance and mechanical strength can be obtained.

The polarizing plate 8 obtained by the above-described manufacturing method can be provided as it is on the optical path of the projection light P as in this embodiment, but only the polarizer 6 from the polarizing plate 8 as in the second embodiment described later. It is also possible to provide the polarizer 6 alone on the optical path of the projection light P.
In the present invention, sunlight that reverses the optical path of the projection light P is attenuated by a simple method of providing the polarizer 6 on the optical path of the projection light P (between the reflector 2 and the display 1 in this embodiment). As a result, the temperature increase of the display 1 can be effectively prevented. On the other hand, since the projection light P emitted from the display 1 can pass through the polarizer 6, it is emitted to the outside of the housing 3 through the reflector 2 and the cover member 4.

By the way, a polarizer is generally a polarizer obtained by adsorbing and stretching a dichroic substance such as iodine on a resin film containing a polyvinyl alcohol resin (hereinafter referred to as an “adsorption-type polarizer”). ) And a polarizer obtained by applying and drying a coating liquid containing an organic dye on an arbitrary application surface (hereinafter referred to as a “coating polarizer”). The polarizer of the present invention is a coating type polarizer.
The polarizer is gradually heated by sunlight that reverses the optical path of the projection light in order to attenuate (ie, absorb) sunlight. Since the adsorptive polarizer is obtained by stretching a resin film on which a dichroic substance is adsorbed, it is easily contracted greatly in the stretching direction by heating with sunlight, and contracts not a little in the non-stretching direction. Therefore, when an absorptive polarizer is affixed to a certain member (adhered body) constituting the projection apparatus, the adherend is easily deformed or the absorptive polarizer is peeled off due to the contraction of the absorptive polarizer. There is a case.
On the other hand, since the coating type polarizer is not obtained by stretching the resin film, it is difficult to shrink by heating, and in particular, the coating type polarizer containing the aromatic disazo compound represented by the general formula (1) is More difficult to shrink. Accordingly, when a coating polarizer containing the aromatic disazo compound represented by the general formula (1) is attached to an adherend, deformation of the adherend due to shrinkage of the coating polarizer, coating polarization, Child separation is less likely to occur.

[Second Embodiment]
FIG. 5 shows a projection apparatus 10 according to the second embodiment of the present invention.
In the first embodiment, the polarizing plate 8 having the substrate 7 and the polarizer 6 is provided on the optical path of the projection light P (between the reflector 1 and the display 2). However, in the present embodiment, the polarizer 6 is provided. Only in the optical path of the projection light P (between the reflector 2 and the cover member 4). The polarizer 6 is supported by a support member (not shown) fixed to the inner wall of the housing 3 in the same manner as the polarizing plate 8 of the first embodiment.
In the present embodiment, similarly to the first embodiment, it is possible to reduce the sunlight S incident on the display device by reversing the optical path of the projection light P.
The polarizer 6 used in the second embodiment may be one obtained by peeling off the polarizer 6 from the substrate 7 included in the polarizing plate 8 of the first embodiment, or on an arbitrary coated surface other than the substrate 7. The formed polarizer 6 may be peeled off. The method for forming the polarizer 6 on an arbitrary coated surface is the same as the method for forming the polarizer 6 on the substrate 7, and thus the description thereof is omitted.

[Third Embodiment]
FIG. 6 shows a projection apparatus 10 according to the third embodiment of the present invention.
The third embodiment is a combination of the configurations of the projection device 10 according to the first embodiment and the projection device 10 according to the second embodiment. In the optical path of the projection light P, the display 1 and the reflector 2 are combined. A polarizing plate 8 having a substrate 7 and a polarizer 6 is provided therebetween, and the polarizer 6 is provided between the reflector 2 and the cover member 4.
In the present embodiment, since the two polarizers 6 are used, the sunlight S that reverses the optical path of the projection light P and irradiates the display device can be further reduced.

  Since the conventional projection apparatus (see FIG. 13) reflects the projection light P twice by the cold mirror 5B and the reflector 2B, the projection apparatus 10B tends to be large. On the other hand, the projector 10 according to the first to third embodiments of the present invention uses the polarizer 6 to attenuate sunlight instead of the cold mirror. Therefore, it is not necessary to reflect the projection light P twice inside the housing 3, and the projector 10 can be further downsized.

[Fourth Embodiment]
FIG. 7 shows a projection apparatus 10 according to the fourth embodiment of the present invention.
The fourth embodiment is a projection apparatus including both the cold mirror 5 and the polarizer 6 of the present invention. The cold mirror 5 is installed above the display device 1, and the projection light P emitted from the display device 1 is guided to the reflector 2 by reflection by the cold mirror 5. That is, in the present embodiment, the projection light P emitted from the display device 1 has an optical path that reaches the outside of the housing 3 through reflection by the cold mirror 5, reflection by the reflector 2, and transmission through the cover member 4.
In the present embodiment, the same polarizing plate 8 having the substrate 7 and the polarizer 6 as in the first embodiment is provided on the optical path of the projection light P and between the cold mirror 5 and the reflector 2.
In the present embodiment, since the sunlight S incident on the display 1 by going back the optical path of the projection light P by both the cold mirror 5 and the polarizing plate 8 is attenuated, the temperature rise of the display 1 is further prevented. Can do.
Although not particularly illustrated, a hot mirror (only infrared light from sunlight is further provided between the cold mirror 5 and the reflector 2 or between the cold mirror 5 and the display 1 on the optical path of the projection light P. A member that absorbs selectively may be provided. By providing the hot mirror, the sunlight S incident on the display 1 by going back the optical path of the projection light P by the three members of the cold mirror 5, the hot mirror, and the polarizer 6 is diminished. Temperature rise can be prevented.

In the first to fourth embodiments described above, the polarizer 6 is provided on the optical path of the projection light P in a state independent of the display 1, the reflector 2, and the cover member 4 included in the projection device 10. However, the polarizer 6 is preferably provided on at least one member selected from the display 1, the reflector 2, and the cover member 4, and at least one selected from the reflector 2 and the cover member 4. More preferably, the cover member 4 is provided on the member.
Hereinafter, fifth to seventh embodiments in which the polarizer 6 is provided on these members will be described.

[Fifth Embodiment]
FIG. 8 shows the display 1 included in the projection apparatus 10 according to the fifth embodiment.
In 5th Embodiment, the polarizing plate 8 similar to 1st Embodiment is provided in the 2nd opening end (opening end which is not obstruct | occluded by the printed circuit board 112 of the light source 11) of the holding member 14 of the indicator 1. FIG.
The member that is most likely to fail due to heating of the display 1 is a liquid crystal display element 13 including an electronic device. By reducing the sunlight S that reverses the optical path of the projection light P at the second opening end of the display 1. The liquid crystal display element 13 can be prevented from being heated.

[Sixth Embodiment]
FIG. 9 shows a reflector included in the projection apparatus according to the sixth embodiment.
In the sixth embodiment, the polarizer 6 is provided in the reflector 2. Specifically, it is laminated on the surface of the mirror part 21 of the reflector 2 (the surface on which the projection light P and sunlight S are incident). Thus, the reflector 2 on which the polarizer 6 is laminated can be easily manufactured by applying the above-described coating liquid to the surface of the mirror portion 21 of the reflector 2 and drying it.
In the present embodiment, the sunlight S that reverses the optical path of the projection light P passes through the cover member 4 and is then partially absorbed by the polarizer 6. Thereafter, the sunlight S that has not been completely absorbed by the polarizer 6 is reflected by the surface of the mirror portion 21 of the reflector 2, and a part of the sunlight S is absorbed when passing through the polarizer 6 again. Thus, in the present embodiment, the sunlight S that travels backward along the optical path of the projection light P is transmitted through the polarizer 6 twice by reflection by the mirror portion 21 of the reflector 2. Therefore, the sunlight S incident on the display 1 can be more effectively reduced by using one polarizer 6.

When the polarizer 6 is provided on the surface of the mirror portion 21 of the reflector 2, the polarizer 6 may be formed using the surface of the mirror portion 21 of the reflector 2 as a coating liquid application surface as described above. The polarizer 6 formed on the coated surface may be peeled off, and the peeled polarizer 6 may be adhered to the surface of the mirror part 21 of the reflector 2 via an adhesive or an adhesive. First Embodiment The same polarizing plate 8 may be adhered to the surface of the mirror part 21 of the reflector 2 through an adhesive or a pressure-sensitive adhesive.
However, when the adhesive or the pressure-sensitive adhesive is interposed between the polarizer 6 and the surface of the mirror portion 21, a part of the projection light P may be absorbed by the adhesive or the pressure-sensitive adhesive, and the light loss of the projection light P may increase. is there. Therefore, the polarizer 6 is preferably formed with the surface of the mirror portion 21 of the reflector 2 as the coating liquid application surface.

[Seventh Embodiment]
FIG. 10 illustrates the cover member 4 and the housing 3 included in the projection apparatus 10 according to the seventh embodiment.
In the seventh embodiment, the polarizer 6 is provided on the cover member 4. Specifically, the polarizer 6 is laminated on the lower surface of the cover member 4 (the surface on the inner side of the housing 3). In this embodiment, since the polarizer 6 is provided on the cover member 4, not only the sunlight S that reverses the optical path of the projection light P but also the inside of the housing 3 without reversely passing the optical path of the projection light P. Incident sunlight (L1 and L2 in FIG. 10) can be reduced. That is, by providing the polarizer 6 on the cover member 4, the total amount of sunlight incident on the inside of the housing 3 can be reduced. Therefore, not only the direct heating of the display 1 due to the incidence of sunlight S that travels backward in the optical path of the projection light P, but also the display 1 that accompanies the temperature rise in the housing 3 by the sunlight L1 and L2. Indirect heating can also be prevented, and the temperature rise of the display 1 can be more effectively prevented.

If the above-described adsorption-type deflector is provided on the cover member, not only may the projection light transmittance decrease due to distortion of the absorption axis and transmission axis of the polarizer due to heating, but also the contraction force of the adsorption-type polarizer. As a result, the cover member warps, and as a result, (i) a gap is formed between the housing and the cover member, and dust enters the inside of the housing through this gap. (Ii) The optical path of the projection light is caused by the warp of the cover member. Problems arise, such as distortion and the inability to properly project projection light onto the translucent reflector.
In this regard, in the present invention, a polarizer including the aromatic disazo compound represented by the general formula (1) described above is used. Therefore, even if a polarizer is provided on the cover member, the polarizer is not easily contracted by heating. Therefore, the cover member is not easily warped, and thus the above problems (i) and (ii) are unlikely to occur.

As a result of extensive research by the present inventor, when the cover member is under the following conditions (A) to (C), the cover member can be prevented from warping particularly markedly as compared with the case of using an adsorption type deflector. I found out that I can do it.
(A) The material of the cover member includes at least one selected from polycarbonate resin, acrylic resin, styrene resin, olefin resin, vinyl chloride resin, amide resin, and imide resin, When at least 1 sort (s) selected from polycarbonate-type resin, acrylic resin, styrene resin, and olefin resin is included, More preferably, when at least 1 sort (s) selected from polycarbonate-type resin and acrylic resin is included.
(B) The lower limit value of the thickness of the cover member is 100 μm, preferably 200 μm, and particularly preferably 300 μm.
(C) The upper limit value of the thickness of the cover member is 700 μm, preferably 600 μm, and particularly preferably 500 μm.

In the present embodiment, the polarizer 6 is provided on the lower surface of the cover member 4, but may be provided on the upper surface of the cover member 4 (surface on the outside of the housing 3). It may be provided on both the upper surface and the lower surface.
When the polarizer 6 is provided on the cover member 4, the polarizer 6 may be formed by using the lower surface and / or the upper surface of the cover member 4 as the coating liquid coating surface, or a polarizer formed on another coating surface. 6 may be peeled off, and the peeled polarizer 6 may be adhered to the lower surface and / or the upper surface of the cover member 4 via an adhesive or a pressure-sensitive adhesive. Or you may adhere | attach on the lower surface and / or upper surface of the cover member 4 via an adhesive.
However, if an adhesive or a pressure-sensitive adhesive is interposed between the polarizer 6 and the cover member 4, a part of the projection light P may be absorbed by the adhesive or the pressure-sensitive adhesive, and the light loss of the projection light P may increase. Therefore, the polarizer 6 is preferably formed with the lower surface and / or the upper surface of the cover member 4 as the coating liquid application surface.

So far, the projection apparatus according to the first to seventh embodiments of the present invention has been described. Of these embodiments, the sixth and seventh embodiments are preferable in consideration of the light loss of the projection light P. Normally, when the projection light P is transmitted through or reflected by a certain member, light loss occurs at the interface between the air and the certain member where the projection light P is incident. For this reason, not all of the projection light P emitted from the display 1 is emitted outside the housing 3. In order to reduce the light loss of the projection light P as much as possible, it is desirable to reduce the number of members through which the projection light P is transmitted or reflected. In this regard, in the sixth and seventh embodiments of the present invention, the polarizer 6 is laminated on the reflector 2 or the cover member 4 (that is, between the reflector 2 and the polarizer 6 or the cover member). 4 and the polarizer 6), the light loss of the projection light P can be reduced.
In addition to the light loss of the projection light P, the seventh embodiment is most preferable in consideration of the total amount of sunlight incident inside the housing 3. In 7th Embodiment, since the polarizer 6 is provided in the cover member 4, not only the sunlight S which reverses the optical path of the projection light P but the other sunlight which enters the inside of the housing | casing 3 can be attenuated. .

The projection apparatus of the present invention is not limited to the specific configurations shown in the first to seventh embodiments, and can be appropriately changed in design within the intended scope of the present invention.
For example, a polarizer can be provided on the surface of the cold mirror shown in the fourth embodiment (see the sixth embodiment). In addition, the sixth and seventh embodiments can be combined, and a polarizer can be provided on both the cover member and the reflector. Furthermore, the cover member having many openings of the housing can be removed from the projection apparatus of the first embodiment.

[Application of projection device]
The projection apparatus of the present invention can be used by being incorporated in a navigation system for a vehicle (for example, an automobile). When the projection apparatus of the present invention is mounted on an automobile, it is preferable to use a windshield as a translucent reflector, but it is also possible to prepare a translucent reflector separately from the windshield and project projection light onto this. is there.
When the projection device of the present invention is applied to a vehicle, it is possible to sufficiently see the situation outside the automobile while clearly displaying an image on the translucent reflector. Therefore, while driving the vehicle, various information can be obtained without changing the line of sight from the traveling direction, and the vehicle can be driven safely.

  The present invention will be described in detail with reference to examples and comparative examples. In addition, this invention is not limited only to the following Example. Each measuring method used in Examples and Comparative Examples is as follows.

[Measurement of warpage]
The optical laminated body produced by the Example and the comparative example was cut out to 150 mm x 150 mm square shape, and the cut piece was obtained. The cut piece was cut out so that the absorption axis of the polarizer extends in a direction parallel to the square piece.
This cut piece was put in a heating container (manufactured by ESPEC Corporation: product name “SPH (H)”) adjusted to 80 ° C. and 5% RH atmosphere, and the cut piece was left to be heated for 24 hours.
After that, the cut piece taken out from the heating container is placed on a horizontal plane as shown in FIG. 11, and the height of the corner farthest from the horizontal plane (distance from the horizontal plane) among the four corners of the cut piece is measured as the amount of warpage. did.

[Synthesis of organic dyes]
4-Nitroaniline and 8-amino-2-naphthalenesulfonic acid are prepared according to a conventional method (Toyo Hosoda, “Theoretical Manufacturing, Dye Chemistry, 5th Edition”, published on July 15, 1968, Technique Hall, pages 135-152. The monoazo compound was obtained by diazotization and coupling reaction by the above method. The obtained monoazo compound was diazotized by the above-mentioned conventional method and further subjected to a coupling reaction with 1-amino-8-naphthol-2,4-disulfonic acid lithium salt to obtain a crude product. This was salted out with lithium chloride to obtain an aromatic disazo compound of the following structural formula (4).

[Example 1]
A norbornene-based resin film (manufactured by Nippon Zeon Co., Ltd .: product name “Zeonor”) was prepared, and the surface of this film was subjected to rubbing treatment and hydrophilization treatment (corona treatment).
The aromatic disazo compound of the structural formula (4) was dissolved in ion exchange water to prepare a coating solution having a concentration of 4% by weight.
By applying the coating liquid on the surface of the substrate subjected to rubbing treatment and hydrophilization treatment using a bar coater (manufactured by BUSHMAN: product name “Mayer rot HS4”), the coating liquid is naturally dried in a thermostatic chamber at 23 ° C. A dry coating film (polarizer) was formed on the surface of the substrate, and the thickness of the polarizer was 300 nm.

Subsequently, the polarizer was peeled from the norbornene-based resin film, and the obtained polarizer was immersed in a water-resistant treatment solution for 2 seconds. As the water-resistant treatment solution, 1,3-propanediamine hydrochloride (manufactured by Tokyo Chemical Industry Co., Ltd.), 1,2-ethylenediamine hydrochloride (manufactured by Tokyo Chemical Industry Co., Ltd.), and bishexamethylenetriamine (Tokyo Chemical Industry Co., Ltd.) Kogyo Co., Ltd.) was used at a mass ratio of 55:15:30.
The polarizer taken out from the water-resistant treatment solution was washed with water and dried to obtain a water-resistant polarizing film.

A water-resistant polarizing film is made of a polycarbonate resin sheet (Mitsubishi Gas Chemical Co., Ltd .: product name “MRF08U”) having a thickness of 300 μm through an acrylic adhesive (manufactured by Nitto Denko Corporation: product name “CS9862UA”). And an optical laminated body was produced.
The amount of warpage after heating was measured for the produced optical laminate according to the method for measuring the amount of warpage described above. The results are shown in Table 1 below.

[Example 2]
An optical laminate was prepared in the same manner as in Example 1 except that the thickness of the polycarbonate-based resin sheet on which the water-resistant polarizing film was bonded was changed to 500 μm.
The amount of warpage after heating was measured for the produced optical laminate according to the method for measuring the amount of warpage described above. The results are shown in Table 1 below.

[Example 3]
An optical laminate was prepared in the same manner as in Example 1 except that a water-resistant polarizing film was bonded to an acrylic resin sheet having a thickness of 500 μm instead of the polycarbonate resin.
The amount of warpage after heating was measured for the produced optical laminate according to the method for measuring the amount of warpage described above. The results are shown in Table 1 below.

[Comparative Example 1]
Implemented except using an adsorptive polarizer (manufactured by Nitto Denko Corporation: product name “SEG1425DU”) obtained by stretching a polyvinyl alcohol-based resin film adsorbed with iodine in place of the water-resistant polarizing film An optical laminate was prepared in the same manner as in Example 1.
The amount of warpage after heating was measured for the produced optical laminate according to the method for measuring the amount of warpage described above. The results are shown in Table 1 below.

[Comparative Example 2]
Implemented except using an adsorptive polarizer (manufactured by Nitto Denko Corporation: product name “SEG1425DU”) obtained by stretching a polyvinyl alcohol-based resin film adsorbed with iodine in place of the water-resistant polarizing film An optical laminate was prepared in the same manner as in Example 2.
The amount of warpage after heating was measured for the produced optical laminate according to the method for measuring the amount of warpage described above. The results are shown in Table 1 below.

[Evaluation]
A comparison between Examples 1 to 3 and Comparative Examples 1 and 2 shows that when a polarizer containing an aromatic disazo compound represented by the general formula (1) of the present application is used, compared with a case where an adsorptive polarizer is used. And it turns out that an optical laminated body does not warp remarkably by heating.

DESCRIPTION OF SYMBOLS 10 ... Projection apparatus, 1 ... Display, 2 ... Reflector, 3 ... Housing, 4 ... Cover member, 5 ... Cold mirror, 6 ... Polarizer, 7 ... Substrate, 8 ... Polarizing plate

Claims (8)

A display that emits projection light; and
A reflector for reflecting the projection light;
A housing having an opening and accommodating the indicator and the reflector inside,
It is represented by the following general formula (1) on the optical path of the projection light, from the exit from the display device to the outside of the housing through the reflection by the reflector and the passage of the opening. A projection device comprising a polarizer containing an aromatic disazo compound.

In the general formula (1), Q ¹ represents a substituted or unsubstituted aryl group, Q ² represents a substituted or unsubstituted arylene group, and R ¹ independently represents a hydrogen atom, substituted or unsubstituted An alkyl group, a substituted or unsubstituted acetyl group, a substituted or unsubstituted benzoyl group, a substituted or unsubstituted phenyl group, M represents a counter ion, m represents an integer of 0 to 2, n Represents an integer of 0-6. However, at least one of m and n is not 0 but 1 ≦ m + n ≦ 6. When m is 2, each R ¹ is the same or different.   The projection device according to claim 1, wherein the opening of the housing is covered with a cover member through which projection light is transmitted.   The projection device according to claim 2, wherein the polarizer is provided on at least one member selected from the indicator, the reflector, and the cover member.   The projection device according to claim 2, wherein the polarizer is provided on the cover member.   The said cover member contains at least 1 sort (s) of resin selected from polycarbonate resin, acrylic resin, styrene resin, olefin resin, vinyl chloride resin, amide resin, and imide resin. The projection device according to any one of 2 to 4.   The projection apparatus according to claim 2, wherein the cover member has a thickness of 10 μm to 1000 μm.   An automobile equipped with the projection device according to any one of claims 1 to 6. A substrate and a polarizer,
The polarizing plate for a projection apparatus, wherein the polarizer contains an aromatic disazo compound represented by the following general formula (1).

In the general formula (1), Q ¹ represents a substituted or unsubstituted aryl group, Q ² represents a substituted or unsubstituted arylene group, and R ¹ independently represents a hydrogen atom, substituted or unsubstituted An alkyl group, a substituted or unsubstituted acetyl group, a substituted or unsubstituted benzoyl group, a substituted or unsubstituted phenyl group, M represents a counter ion, m represents an integer of 0 to 2, n Represents an integer of 0-6. However, at least one of m and n is not 0 but 1 ≦ m + n ≦ 6. When m is 2, each R ¹ is the same or different.

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