JP2021047447A - screen - Google Patents

Abstract

To provide a screen that presents an image clearly visible as much as possible.SOLUTION: A screen 1 is constituted by a light-transmitting plate member, and an image is projected onto an inner surface S1 of the screen. The screen 1 includes: a first resin layer 2 that is a polarizing layer composed of a polarizer; and second resin layers 3A, 3B disposed on either surface of the first resin layer 2, which are resin layers essentially comprising a polycarbonate resin and having a thickness of 0.2 mm or more and a retardation of 2400 nm or more and 6000 nm or less, arranged in such a manner that a slow axis of the resin layer is in the same direction as an absorption axis of the polarizing layer. When reflected light CL is incident to an outer surface S2, the screen 1 can suppress transmission of the reflected light CL to the inner surface S1.SELECTED DRAWING: Figure 6

Description

The present invention relates to a screen.

In recent years, a head-up display device mounted on an automobile is known (see, for example, Patent Document 1). The head-up display device described in Patent Document 1 irradiates red (R), green (G), and blue (B) laser beams from a laser light source, respectively, and uses a windshield as a screen to display an image on the screen. Can be formed.

However, for example, when the reflected light reflected by sunlight on the asphalt or the hood of an automobile passes through the windshield, there is a problem that the reflected light makes it difficult to see the image on the screen.

JP 2015-225244

An object of the present invention is to provide a screen capable of visually recognizing an image as clearly as possible.

Such an object is achieved by the present invention of the following (1) to (16).
(1) A screen composed of a light-transmitting plate member and an image is projected on one surface of the plate member.
A polarizing layer composed of polarizers and
A resin layer provided on at least one surface side of the polarizing layer, mainly composed of a polycarbonate resin, having a thickness of 0.2 mm or more, a retardation of 2400 nm or more, and a retardation of 6000 nm or less, and the slow axis thereof is the polarizing layer. With a resin layer arranged in the same direction as the absorption axis of
A screen characterized in that when external light is incident on the other surface of the plate member opposite to the one surface, the transmission of the external light to the one surface of the plate member is suppressed.

(2) The screen according to (1) above, wherein the one surface side of the plate member is concave and the other surface side is convex.

(3) It is used in an upright position.
The screen according to (1) or (2) above, wherein the absorption axis is inclined within ± 45 degrees with respect to the horizontal direction.

(4) The screen according to any one of (1) to (3) above, wherein the resin layer is a sheet material mainly composed of the polycarbonate resin stretched in one direction.

(5) The screen according to any one of (1) to (4) above, wherein the thickness of the resin layer is 3.0 mm or less.

(6) The screen according to any one of (1) to (5) above, wherein the resin layer is provided on both side surfaces of the polarizing layer.
(7) The screen according to (6) above, wherein the thickness of each resin layer is the same.

(8) The screen according to (6) or (7) above, wherein one of the resin layers contains a metal oxide.

(9) The screen according to (8) above, which is provided on a resin layer containing the metal oxide and includes a hard coat layer mainly composed of an ultraviolet curable resin.

(10) The screen according to (8) or (9) above, wherein the resin layer side containing the metal oxide is used so as to face the incident side of the external light.

(11) The screen according to any one of (1) to (10) above, wherein the polarizing layer is mainly composed of a polyvinyl alcohol resin.

(12) The screen according to (11) above, wherein the polarizing layer is a state in which a sheet material mainly composed of the polyvinyl alcohol resin is stretched in one direction.

(13) The screen according to any one of (1) to (12) above, wherein the thickness of the polarizing layer is 0.01 mm or more and 0.03 mm or less.

(14) The screen according to any one of (1) to (13) above, comprising a bonding layer for bonding the polarizing layer and the resin layer.

(15) The screen according to any one of (1) to (14) above, wherein the total thickness of the plate member is 0.6 mm or more and 5.0 mm or less.

(16) The screen according to any one of (1) to (15) above, which is used as a combiner.

According to the present invention, the image can be visually recognized as clearly as possible.

FIG. 1 is a side view showing an embodiment when the screen of the present invention is applied to a combiner. FIG. 2 is an enlarged cross-sectional view of the region [A] surrounded by the alternate long and short dash line in FIG. FIG. 3 is a perspective view of the screen in FIG. FIG. 4 is a cross-sectional view taken along the line BB in FIG. FIG. 5 is a cross-sectional view taken along the line CC in FIG. FIG. 6 is an enlarged cross-sectional view of the screen in FIG.

Hereinafter, the screen of the present invention will be described in detail based on the preferred embodiments shown in the accompanying drawings.

FIG. 1 is a side view showing an embodiment when the screen of the present invention is applied to a combiner. FIG. 2 is an enlarged cross-sectional view of the region [A] surrounded by the alternate long and short dash line in FIG. FIG. 3 is a perspective view of the screen in FIG. FIG. 4 is a cross-sectional view taken along the line BB in FIG. FIG. 5 is a cross-sectional view taken along the line CC in FIG. FIG. 6 is an enlarged cross-sectional view of the screen in FIG. In the following, for convenience of explanation, the upper side in FIGS. 1 to 4 and 6 is referred to as "upper" or "upper", and the lower side is referred to as "lower" or "lower". Further, the left side in FIGS. 1 and 2 is referred to as "front" or "front", and the right side is referred to as "rear" or "rear". Further, in FIG. 6, in order to facilitate understanding, the screen is shown in a flat state, and the thickness direction is exaggerated and schematically shown.

As shown in FIGS. 1 and 2, the automobile 100 is equipped with a head-up display 10. The head-up display 10 is built in the upper part of the dashboard 101.

Further, a screen 1 used as a combiner is arranged between the head-up display 10 and the windshield 102. The "combiner" means that when the head-up display 10 is used, the image (video) projected from the head-up display 10 onto the screen 1 and the windshield 102, that is, the scenery in front of the driver H are superimposed. Say what you want to see. The screen 1 is supported on the dashboard 101 via a support portion (not shown) in an upright state.

As shown in FIG. 2, the head-up display 10 includes a light source 11, a reflecting member 12, and an accommodating body 13.

The light source 11 can independently irradiate the laser light LS of each color of red (R), green (G), and blue (B). Then, an image can be formed by controlling the irradiation timing of the laser beam LS of each color while scanning the light source 11.

The reflecting member 12 is composed of, for example, a prism, and can reflect the laser beam LS from the light source 11. The laser beam LS reflected by the reflecting member 12 is projected onto the screen 1. Then, this projected light is recognized by the driver H as the image (see FIGS. 1 and 2).

As shown in FIG. 2, the storage body 13 has a box shape, and a light source 11, a reflection member 12, and other parts constituting the head-up display 10 can be stored inside the storage body 13. Further, the storage body 13 has a window portion 131 formed of an opening that opens toward the windshield 102 side. Through the window portion 131, the laser beam LS is emitted toward the outside of the housing body 13, that is, toward the screen 1.

Further, a transparent cover member 14 is installed in the window portion 131 of the storage body 13 so as to cover the window portion 131. As a result, it is possible to prevent foreign matter such as dust and dirt from entering the storage body 13 through the window portion 131, and thus the lens and the reflective member 12 of the light source 11 become cloudy or dirty due to the foreign matter. Can be prevented.

As shown in FIGS. 3 and 6, the screen 1 is composed of a plate member having light transmission. One surface of the screen 1 (hereinafter referred to as "inner surface S1") is the driver H side, that is, the inside (rear), and the other surface opposite to the one surface (hereinafter referred to as "outer surface S2"). Is arranged so as to face the windshield 102 side, that is, the outside (front).

As shown in FIGS. 3 to 5, the screen 1 is curved so that the inner surface S1 side is concave and the outer surface S2 side is convex. As a result, the laser beam LS emitted from the head-up display 10 toward the inner surface S1 is reflected by the inner surface S1 and is visually recognized as an image by the driver H (see FIGS. 1 and 2). ..

Further, on the inner surface S1, the mean curvature k ₁ along the vertical direction (see FIG. 4) and the mean curvature k ₂ along the horizontal direction (see FIG. 5) are different. The mean curvature k ₁ is larger than the _{mean curvature k 2 in the} configurations shown in FIGS. 4 and 5, but may be smaller than the _{mean curvature k 2.}

As shown in FIG. 6, the screen 1 has a first resin layer 2, a second resin layer 3A and a second resin layer 3B, a bonding layer 4A and a bonding layer 4B, a hard coat layer 5A and a hard coat. It is a laminated board including the layer 5B. Hereinafter, each layer will be described.

The first resin layer 2 is an intermediate layer located at the center of the screen 1 in the thickness direction, and the thickness t ₂ is a constant portion in the surface direction of the screen 1.

The first resin layer 2 is mainly composed of polyvinyl alcohol (PVA) resin. In the present embodiment, the first resin layer 2 is a polyvinyl alcohol resin dyed with a dichroic dye typified by iodine or a dichroic dye, and crosslinked with a boron compound or the like. The content of the polyvinyl alcohol resin in the first resin layer 2 is preferably 0.2% or more and 8% or less, and more preferably 0.5% or more and 5% or less.

Further, the first resin layer 2 is a processed sheet material (film) made of the constituent material. That is, the sheet material is a sheet material thicker than _{the thickness t 2} of the first resin layer 2 on the screen 1, and the sheet material is stretched in one direction until the _{thickness t 2 is reached.} As a result, it is used (obtained) as the first resin layer 2. As a result, the first resin layer 2 becomes a polarizing layer that functions as a polarizing element.

The thickness t ₂ is not particularly limited, and is preferably 0.01 mm or more and 0.03 mm or less, for example. If the thickness t ₂ is less than 0.01 mm, the first resin layer 2 may not sufficiently function as a polarizer, and even if the _{thickness t 2 exceeds 0.03 mm, it may not function sufficiently.} The above-mentioned improvement of the function as a polarizer cannot be expected.

The refractive index of the first resin layer 2 is not particularly limited, and is preferably 1.52 or more and 1.67 or less, and more preferably 1.54 or more and 1.60 or less.

As shown in FIG. 6, the second resin layer 3A is arranged on the left side surface 21 side of the first resin layer 2, and the second resin layer 3B is arranged on the right side surface 22 side. There is. Since the second resin layer 3A and the second resin layer 3B have the same configuration except that the arrangement location is different and the second resin layer 3A contains the metal oxide particles 31, the second resin layer 3A and the second resin layer 3B have the same configuration. The resin layer 3A of No. 2 will be typically described.

The second resin layer 3A is mainly composed of a polycarbonate resin. The polycarbonate resin preferably has a weight average molecular weight of 19000 or more and 40,000 or less, and more preferably 19,500 or more and 35,000 or less. As a result, the second resin layer 3A has, for example, sufficient impact resistance.

Further, the second resin layer 3A is a processed material of a polycarbonate resin sheet containing metal oxide particles 31. That is, the sheet material is a sheet material thicker than _{the thickness t 3A} of the second resin layer 3A on the screen 1, and the sheet material is stretched in one direction until the _{thickness t 3A is reached.} As a result, it is used as the second resin layer 3A. As a result, the second resin layer 3A has retardation (birefringence × thickness). The retardation is preferably, for example, 2400 nm or more and 6000 nm or less, and more preferably 3000 nm or more and 5600 nm or less.

The thickness t _{3A (the same applies to the thickness t 3B} of the second resin layer 3B) is 0.2 mm or more and 3.0 mm or less, preferably 0.3 mm or more and 2.5 mm or less. If the thickness t _3A is less than 0.2 mm, it may not be expected that the second resin layer 3A will have the retardation. Further, if the thickness t _3A exceeds 3.0 mm, the weight of the screen 1 increases, which may make installation difficult. Further, the thickness t _3A and the thickness t _3B may be different, but are preferably the same. When the thickness t _3A and the thickness t _3B are the same, there is an advantage that warpage is less likely to occur when exposed to a high temperature.

The second resin layer 3A having such a configuration and the second resin layer 3B having a configuration in which the particles 31 are omitted from the second resin layer 3A have their slow-phase axes of the first resin layer 2, respectively. It is arranged so as to be in the same direction as the absorption axis. The "slow phase axis" is a direction in which the speed of light passing through the second resin layer 3A and the second resin layer 3B is slow (phase is delayed), and on the contrary, the speed of light traveling. The direction in which the speed is fast (the phase advances) is called the "phase advance axis" of the phase element. The deviation between the slow phase axis and the absorption axis is allowed within ± 5 degrees. Further, the absorption axis may be tilted as long as it is within ± 45 degrees with respect to the polarization direction emitted from the head-up display 10.

By the way, as shown in FIG. 1, while the automobile 100 is traveling, the automobile 100 has a reflected light CL reflected by sunlight (natural light) on the bonnet 103 of the automobile 100 and the road surface 200 on which the automobile 100 travels. May be incident. Then, as shown in FIG. 6, the reflected light CL is incident on the outer surface S2 of the screen 1 in an attempt to pass through the screen 1. The reflected light CL is S-polarized light, and in the screen 1, the absorption axis of the first resin layer 2 is in the S direction, and as described above, the second resin layer 3A and the second resin layer 3A are in the same direction as the absorption axis. There is each slow axis of the second resin layer 3B. As a result, the reflected light CL is absorbed by the screen 1 and transmission to the inner surface S1 is suppressed, so that the driver H can visually recognize the image on the screen 1 as clearly as possible. Further, the light LS emitted from the head-up display 10 is reflected on the driver H side of the screen 1 to provide information to the driver H. On the other hand, the unreflected light LS is absorbed by the first resin layer 2 and reduced to the extent that it does not substantially cause a double image. In this way, the screen 1 functions as a polarizing plate.

Further, as described above, the second resin layer 3A and the second resin layer 3B are provided on both side surfaces of the first resin layer 2, respectively. In this configuration, the head-up that transmits the reflected light CL and the windshield 102 side is compared with the case where the second resin layer 3A or the second resin layer 3B is provided on one side of the first resin layer 2. It contributes to maintaining the function of absorbing the light LS of the display 10 in the environment inside the vehicle.

The refractive index of the second resin layer 3A and the second resin layer 3B is not particularly limited, and is preferably 1.58 or more and 1.60 or less, and 1.585 or more and 1.595 or less. Is more preferable.

As shown in FIG. 6, the metal oxide particles 31 are dispersed and contained in the second resin layer 3A. The particles 31 are IR (Infrared Rays) cut materials capable of absorbing infrared rays contained in sunlight. Thereby, for example, it is possible to suppress the temperature rise of the screen 1 under the scorching sun and prevent deformation and deterioration due to heat.

Further, in the screen 1, the second resin layer 3A side containing the metal oxide particles 31 faces the windshield 102, that is, the incident side of the reflected light CL, and the second resin layer 3B side faces the incident side of the laser light LS. Face to. As a result, it is possible to prevent the metal oxide particles 31 from interfering with the image and reducing the visibility of the image as much as possible.

Further, the first resin layer 2 and the second resin layer 3A are bonded via the bonding layer 4A, and the first resin layer 2 and the second resin layer 3B are bonded via the bonding layer 4B. Has been done. The bonding layer 4A and the bonding layer 4B are various adhesives or pressure-sensitive adhesives such as urethane adhesives, epoxy adhesives, acrylic adhesives, and acrylic pressure-sensitive adhesives. As a result, the layers can be reliably joined to each other, and the screen 1 can withstand long-term use.

The thickness t _{4A of the bonding layer 4A and the thickness t 4B} of the bonding layer 4B are not particularly limited, and are preferably 0.005 mm or more and 0.02 mm or less, preferably 0.006 mm or more and 0.015 mm. It is more preferable that it is as follows. If the thickness t _4A and the thickness t _4B are less than 0.005 mm, the adhesive strength may be lowered, and even if the thickness t _4A and the thickness t _4B exceed 0.02 mm, the adhesive strength may be lowered. Cannot be expected to improve the adhesive strength of. Further, the thickness t _4A and the thickness t _4B may be different, but are preferably the same.

The refractive index of the bonding layer 4A and the bonding layer 4B is not particularly limited, and is preferably 1.46 or more and 1.55 or less, and more preferably 1.461 or more and 1.545 or less. ..

A hard coat layer 5A is provided on the second resin layer 3A. This makes it possible to protect the second resin layer 3A, which is relatively easily scratched. The hard coat layer 5A is obtained by applying a varnish-like material to be the hard coat layer 5A on the second resin layer 3A and irradiating the coated material with ultraviolet rays to cure the hard coat layer 5A.

Similarly, the hard coat layer 5B is also provided on the second resin layer 3B. This makes it possible to protect the second resin layer 3B, which is relatively easily scratched. The hard coat layer 5B is also obtained by applying a varnish-like material to be the hard coat layer 5B on the second resin layer 3B and irradiating the coated material with ultraviolet rays to cure the hard coat layer 5B. In the screen 1, the hard coat layer 5B can be omitted.

The hard coat layer 5A and the hard coat layer 5B are each composed of an ultraviolet curable resin, and examples of the ultraviolet curable resin include an ultraviolet curable resin containing an acrylic compound as a main component, a urethane acrylate oligomer, or a polyester urethane acrylate. Examples thereof include an ultraviolet curable resin containing at least one selected from the group of an ultraviolet curable resin containing an oligomer as a main component, an epoxy resin, and a vinylphenol resin as a main component. Among these, an ultraviolet curable resin containing an acrylic compound as a main component is preferable. Thereby, the adhesion with each resin layer can be improved.

The thickness t _{5A of} the hard coat layer 5A and the thickness t _5B of the hard coat layer 5B are not particularly limited, and are preferably 0.002 mm or more and 0.020 mm or less, preferably 0.003 mm or more and 0. It is more preferably .015 mm or less. Further, the thickness t _5A and the thickness t _5B may be different, but are preferably the same.

The refractive index of the hard coat layer 5A and the hard coat layer 5B is not particularly limited, and is preferably 1.40 or more and 1.60 or less, and 1.450 or more and 1.595 or less. More preferred.

_{The total thickness t 1} of the screen 1 having the above configuration is preferably, for example, 0.4 mm or more and 5.0 mm or less, and more preferably 0.65 mm or more and 4.0 mm or less. As a result, the screen 1 can be made as thin as possible. Further, the screen 1 has a rigidity sufficient to withstand normal use in the automobile 100, and can maintain a curved shape.

The screen 1 has a rectangular shape in a plan view, and is preferably 50 mm or more and 200 mm or less in length, more preferably 60 mm or more and 190 mm or less, and 100 mm or more and 400 mm or less in width. It is preferably 130 mm or more, and more preferably 380 mm or less.

Although the screen of the present invention has been described above with respect to the illustrated embodiment, the present invention is not limited to this, and each part constituting the screen is replaced with an arbitrary configuration capable of exhibiting the same function. can do. Further, any component may be added.

Further, the screen of the present invention may be a combination of any two or more configurations (features) of each of the above-described embodiments.

Further, the screen is provided with a second resin layer on both sides of the first resin layer, but the screen is not limited to this, and one second resin layer may be omitted.

1 Screen 2 First resin layer 21, 22 surfaces 3A, 3B Second resin layer 31 Particles 4A, 4B Bonding layer 5A, 5B Hard coat layer 10 Head-Up Display
11 Light source 12 Reflective member 13 Storage body 131 Window part 14 Cover member 100 Automobile 101 Dashboard 102 Windshield 103 Bonnet 200 Road surface H Driver k ₁ , k ₂ Mean curvature LS Laser light CL Reflected light t ₁ Total thickness t ₂ , t _3A , t _3B , t _4A , t _4B , t _5A , t _5B Thickness S1 Inner surface S2 Outer surface

Such an object is achieved by the present invention of the following (1) to ( 13).
(1) A screen composed of a light-transmitting plate member and an image is projected on one surface of the plate member.
A polarizing layer composed of polarizers and
A resin layer provided on both sides of the polarizing layer, mainly composed of a polycarbonate resin, having a thickness of 0.2 mm or more, a retardation of 2400 nm or more, and a retardation of 6000 nm or less, the slow axis thereof absorbing the polarizing layer. A resin layer arranged in the same direction as the axis ,
A hard coat layer provided on each of the resin layers and mainly composed of an ultraviolet curable resin is provided.
The refractive index of the polarizing layer is 1.52 or more and 1.67 or less.
The refractive index of each of the resin layers is 1.58 or more and 1.60 or less, respectively.
The refractive index of each of the hard coat layers is 1.40 or more and 1.60 or less, respectively.
A screen characterized in that when external light is incident on the other surface of the plate member opposite to the one surface, the transmission of the external light to the one surface of the plate member is suppressed.

( 3 ) The screen according to (1) or (2) above, wherein the resin layer is a state in which a sheet material mainly composed of the polycarbonate resin is stretched in one direction.

( 4 ) The screen according to any one of (1) to (3 ) above, wherein the thickness of the resin layer is 3.0 mm or less.

(5 ) The screen according to any one of (1) to (4) above, wherein the thickness of each resin layer is the same.

( 6 ) The screen according to any one of (1) to (5) above, wherein one of the resin layers contains a metal oxide.

( 7 ) The screen according to (6) above, wherein the resin layer side containing the metal oxide is used so as to face the incident side of the external light.

( 8 ) The screen according to any one of (1) to (7 ) above, wherein the polarizing layer is mainly composed of a polyvinyl alcohol resin.

( 9 ) The screen according to (8 ) above, wherein the polarizing layer is a sheet material mainly composed of the polyvinyl alcohol resin stretched in one direction.

( 10 ) The screen according to any one of (1) to (9 ) above, wherein the thickness of the polarizing layer is 0.01 mm or more and 0.03 mm or less.

( 11 ) The screen according to any one of (1) to (10 ) above, comprising a bonding layer for bonding the polarizing layer and the resin layer.

( 12 ) The screen according to any one of (1) to (11 ) above, wherein the total thickness of the plate member is 0.6 mm or more and 5.0 mm or less.

( 13 ) The screen according to any one of (1) to (12 ) above, which is used as a combiner.

Claims (16)

A screen composed of a light-transmitting plate member and an image is projected on one surface of the plate member.
A polarizing layer composed of polarizers and
A resin layer provided on at least one surface side of the polarizing layer, mainly composed of a polycarbonate resin, having a thickness of 0.2 mm or more, a retardation of 2400 nm or more, and a retardation of 6000 nm or less, and the slow axis thereof is the polarizing layer. With a resin layer arranged in the same direction as the absorption axis of
A screen characterized in that when external light is incident on the other surface of the plate member opposite to the one surface, the transmission of the external light to the one surface of the plate member is suppressed. The screen according to claim 1, wherein the one side of the plate member is concave and the other side is convex. It is used in an upright position.
The screen according to claim 1 or 2, wherein the absorption axis is inclined within ± 45 degrees with respect to the horizontal direction. The screen according to any one of claims 1 to 3, wherein the resin layer is a state in which a sheet material mainly composed of the polycarbonate resin is stretched in one direction. The screen according to any one of claims 1 to 4, wherein the thickness of the resin layer is 3.0 mm or less. The screen according to any one of claims 1 to 5, wherein the resin layer is provided on both side surfaces of the polarizing layer. The screen according to claim 6, wherein the thickness of each resin layer is the same. The screen according to claim 6 or 7, wherein one of the resin layers contains a metal oxide. The screen according to claim 8, further comprising a hard coat layer provided on the resin layer containing the metal oxide and mainly composed of an ultraviolet curable resin. The screen according to claim 8 or 9, wherein the resin layer side containing the metal oxide is used so as to face the incident side of the external light. The screen according to any one of claims 1 to 10, wherein the polarizing layer is mainly made of a polyvinyl alcohol resin. The screen according to claim 11, wherein the polarizing layer is a state in which a sheet material mainly composed of the polyvinyl alcohol resin is stretched in one direction. The screen according to any one of claims 1 to 12, wherein the thickness of the polarizing layer is 0.01 mm or more and 0.03 mm or less. The screen according to any one of claims 1 to 13, further comprising a bonding layer for bonding the polarizing layer and the resin layer. The screen according to any one of claims 1 to 14, wherein the total thickness of the plate members is 0.6 mm or more and 5.0 mm or less. The screen according to any one of claims 1 to 15, which is used as a combiner.

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