JP2007264038A - Transparent member for external light reflection prevention and vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent member for external light reflection prevention and a vehicle, capable of suppressing the reflecting of external light to a display surface of a display device. <P>SOLUTION: The transparent member 14 for external light reflection prevention used in a structural body arranged with the display device having the display surface selectively blocks the polarized light component, of the natural light 10, vibrating approximately parallel to the display surface of the display device when the natural light 10 is transmitted toward the display surface of the display device. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a transparent member for preventing external light reflection and a vehicle. More specifically, the present invention relates to a transparent member for preventing external light reflection and a vehicle that are preferably used for automobile windows and the like.

An in-vehicle display device (hereinafter also referred to as “in-vehicle display”) is generally placed in front of a driver seat or a passenger seat in an automobile, and is a car navigation system that displays a road map, a remaining fuel. It is used for various purposes as a monitor indicating the amount or the like, a television broadcast receiver or the like. As such an in-vehicle display, at present, a liquid crystal display device is generally used from the viewpoint of thin and light weight and low power consumption.

However, with respect to the in-vehicle display, visibility may not be sufficiently obtained due to the location of the display. For example, when an in-vehicle display is placed in front of the driver's seat or passenger seat, when external light enters from the front side window, the external light is reflected by the film surface of the polarizer mounted in the display. As a result, so-called reflection of external light may be visually recognized from the driver's seat and the passenger seat on the display surface of the display.

Therefore, as a method to suppress the reflection of external light on the display surface of the display, anti-glare treatment (anti-glare treatment) and low reflection treatment (low reflection treatment) are performed on the film surface on the display surface side (observation surface side) of the polarizer. Alternatively, a method for applying an antireflection treatment (anti-reflection treatment), a method for applying an antireflection film, and the like are disclosed. For example, in Patent Document 1, a display pixel layer and a front transparent plate layer are laminated, an antireflection film is formed on the front side of the front transparent plate layer, and a light scattering rough surface is formed on the rear side of the front transparent plate layer. A display device is disclosed. Further, Patent Document 2 discloses an antireflection film in which a low refractive index layer is formed directly or via another layer on a transparent substrate film. Furthermore, Patent Document 3 discloses the use of a polymer film on which a multilayer optical interference system is mounted as an antireflection system. However, according to these methods, the reflection of external light on the display surface is not sufficiently suppressed.

In Patent Document 4, for the purpose of preventing the image of the display surface from being reflected on the windshield, the direction of polarization of the light emitted from the display surface of the liquid crystal display device is the average of the drivers coming out of the display surface. An in-vehicle liquid crystal display device is disclosed in which a light beam incident on the position of the line of sight is set in parallel to the incident surface of the windshield and combined, and this display device reflects external light on the display surface. It is not intended to prevent intrusion.
JP-A-6-301020 JP-A-9-145903 JP-A-2005-526639 JP-A-1-302383

The present invention has been made in view of the above situation, and an object thereof is to provide a transparent member for preventing reflection of external light and a vehicle that can suppress reflection of external light on a display surface of a display device. To do.

The present inventor has conducted various studies on the phenomenon in which external light is reflected on the display surface of the display device. As a result, the general light property, that is, the S-polarized component (the polarized component whose light vibration surface is substantially perpendicular to the reflecting surface) is obtained. Attention was focused on the property (see, for example, FIG. 2) that the reflectance is higher than the P-polarized light component (the polarized light component in which the vibration plane of light is substantially parallel to the reflecting surface). Then, by separating external light into a polarization component (P-polarization component) substantially perpendicular to the display surface of the display device whose light vibration surface is a reflection surface and a polarization component (S-polarization component) substantially parallel to the conventional display surface, In the automobile (structure), as shown in FIG. 3, as a result of the S-polarized component 10S of the external light (natural light) 10 being reflected on the display surface of the display device 12, the driver 13 reflects external light on the display surface. I found it to be visible. Therefore, for example, as shown in FIG. 1, when the polarizing film (transparent member for preventing reflection of external light) 14 transmits the external light 10 toward the display surface of the display device 12, the display of the external light 10 is performed. As a result of selectively blocking the polarization component (S polarization component) 10S that vibrates substantially parallel to the display surface of the device 12, the S polarization component 10S reflected by the display surface of the display device 12 is reduced, The present inventors have found that the driver 13 can suppress the reflection of the external light 10 on the display surface, and have conceived that the above problem can be solved brilliantly, thereby achieving the present invention.

That is, the present invention is a transparent member for preventing external light reflection used in a structure in which a display device having a display surface is disposed, and the transparent member for preventing external light reflection is such that natural light is displayed on the display device. This is a transparent member for preventing reflection of external light, which selectively blocks polarized light components that vibrate substantially parallel to the display surface of the display device among the natural light when transmitted toward the surface.
The present invention is described in detail below.

The transparent member for preventing external light reflection according to the present invention is used for a structure in which a display device having a display surface is arranged. The transparent member for preventing external light reflection is used for the purpose of preventing external light from being reflected on the display surface of the display device in the structure in which the display device is disposed. Various members, such as a film stuck to a window and a partition plate, are mentioned. The transparency of the transparent member for preventing reflection of outside light is not particularly limited as long as it is in a range that cannot be regarded as light-shielding property (optical density OD value ≧ 3), and may be translucent. High is preferred. The display surface refers to a two-dimensional display medium that displays a display image. The display device is not particularly limited as long as it can display a display image on the display surface, such as an on-vehicle display device such as a car navigation system, an aircraft and ship radar, a monitor showing the remaining amount of fuel, etc. Is mentioned. Examples of the display device include a liquid crystal display device and an organic electroluminescence (EL) display device. The structure is not particularly limited as long as the display device is arranged, and vehicles such as automobiles, two-wheeled cars and trains, ships, airplanes, their toys, houses and high-rise buildings, etc. Can be mentioned.

The transparent member for preventing reflection of external light is a polarized light component (S-polarized light component) that vibrates substantially parallel to the display surface of the display device when the natural light is transmitted toward the display surface of the display device. Is selectively blocked. That is, the transparent member for preventing external light reflection is a polarized light component (P-polarized light component) that vibrates substantially perpendicularly to the display surface of the display device when the natural light is transmitted toward the display surface of the display device. ) Is selectively transmitted. According to this, since the S-polarized component having a high reflectance is blocked by the external light reflection preventing transparent member and the S-polarized component 10S reaching the display surface of the display device is reduced, the external light on the display surface is reduced. Can be suppressed.

In this specification, natural light refers to light in which polarized light having various vibration directions is mixed and does not exhibit anisotropy. “Selectively block the S-polarized component” and “selectively transmit the P-polarized component” means that when natural light is transmitted, the S-polarized component (or P-polarized component) of the natural light is the P-polarized component. It means that the ratio of being blocked (or transmitted) is larger than (or S-polarized component), and particularly preferably means that the S-polarized component is almost completely blocked and the P-polarized component is almost completely transmitted. The term “substantially parallel” (or “substantially vertical”) means a state in which it is completely parallel (or vertical), but it is not in a state of being parallel (or vertical) within a range that can be regarded as being completely parallel (or vertical). Is also included.

As a method for measuring the polarization characteristics of the transparent member for preventing external light reflection, for example, a polarized light is emitted from a light source using a polarization characteristics evaluation apparatus (trade name: RETS-100, manufactured by Otsuka Electronics Co., Ltd.) This can be obtained by transmitting the transparent member for preventing reflection of light and detecting the passing light with a detection device. From this measurement result, it is possible to know how the transparent member for preventing reflection of external light acts when natural light is incident.

The configuration of the transparent member for preventing reflection of external light is not particularly limited. For example, (1) a film in which iodine or a dichroic dye is adsorbed and oriented on a film such as (1) polyvinyl alcohol (PVA) (hereinafter referred to as “polarizing film”). (2) The polarizing film of (1) is sandwiched between protective films made of triacetyl cellulose (TAC) or the like, (3) glass with polarizing properties, (4) polarizing coating on glass And the like.

The configuration of the transparent member for preventing external light reflection according to the present invention is not particularly limited as long as it has the above-described polarization characteristics. For example, the display device may include a polarizer having a film surface that is substantially parallel to the display surface. In this case, the transparent member for preventing reflection of external light causes natural light to be displayed on the display device. It is preferable to selectively block a polarized component (S-polarized component) that vibrates substantially parallel to the film surface of the polarizer in the natural light when transmitted toward the surface. That is, the display device includes a polarizer having a film surface substantially parallel to the display surface, and the transparent member for preventing external light reflection is when natural light is transmitted toward the display surface of the display device. In addition, it is preferable to selectively transmit a polarized component (P-polarized component) that vibrates substantially perpendicularly to the film surface of the polarizer in the natural light. When the display device is a direct-view type display device that directly looks at the display, reflection of external light on the display surface is mainly caused by reflection of external light (S-polarized light component) on the film surface of the polarizer. Yes. According to this embodiment, since reflection of the S-polarized component on the film surface of the polarizer can be reduced, reflection of external light on the display surface can be effectively suppressed. In order to obtain the effects of the present invention more effectively, an anti-glare treatment (anti-glare treatment), a low reflection treatment (low reflection treatment) and / or a film surface on the display surface (observation surface) side of the polarizer are used. It is preferable that an antireflection treatment (anti-reflection treatment) is performed. Moreover, it is preferable that a film having a mat surface, an antireflection film using light interference, or the like is attached to the film surface on the display surface side of the polarizer.

The term “polarizer” as used herein means, for example, a polarizer disposed on the display surface side of the liquid crystal cell when the display device is a liquid crystal display device, and the display device is an organic EL display device. In this case, the polarizer is disposed on the display surface side of the light emitting layer. The configuration of the polarizer is not particularly limited, and (1) a film such as polyvinyl alcohol (PVA) in which iodine or a dichroic dye is adsorbed and oriented (hereinafter also referred to as “linear polarizer”), (2) a straight line A polarizer sandwiched between protective films made of triacetylcellulose (TAC) or the like, (3) a linear polarizer (observation surface side), and a wave plate such as a half-wave plate or a quarter-wave plate ( And the like (circular polarizer or elliptical polarizer) formed by stacking the back side and the like.

In the case where the display device is a projection type display device for viewing an image projected on a screen, the display device has a screen serving as a display surface. It is preferable to block polarized light components that oscillate in a direction substantially parallel to the screen in the incident natural light when transmitted toward the screen. According to this, since reflection of the S polarization component on the screen can be suppressed, reflection of external light on the display surface can be effectively suppressed.

Since reflection of light occurs at the interface of media having different refractive indexes, reflection of external light on the display surface of the display device is caused by the outermost surface of the display device or the interface of materials having different refractive indexes in the display device. This is considered to be caused by reflection of external light. Therefore, the transparent member for preventing reflection of external light is substantially parallel to the outermost surface of the display device and the interface of materials having different refractive indexes in the display device when natural light is transmitted toward the display surface of the display device. It is preferable to selectively block the oscillating polarization component, for example, on the surface of a glass material or plastic material that constitutes the outermost surface of the display device, on the interface between the glass material and the metal material in the display device, etc. On the other hand, it is preferable to selectively block polarized components that vibrate substantially in parallel.

The present invention is also a vehicle including a window and a vehicle-mounted display device having a display surface, and the window is mounted on the vehicle when natural light is transmitted toward the display surface of the vehicle-mounted display device. It is also a vehicle that selectively blocks a polarized component (S-polarized component) that vibrates substantially parallel to the display surface of the display device. That is, the present invention is also a vehicle including a window and an in-vehicle display device having a display surface, wherein the natural light is transmitted when the natural light is transmitted toward the display surface of the in-vehicle display device. Of these, the vehicle selectively transmits a polarized component (P-polarized component) that vibrates substantially perpendicularly to the display surface of the in-vehicle display device. According to this, since the S-polarized component having a high reflectance is blocked by the window and the S-polarized component reaching the display surface of the in-vehicle display device is reduced, external light to the display surface of the in-vehicle display device is reduced. Reflection can be suppressed.

The window is not particularly limited, and examples thereof include a side window, a front window, a front side window, a rear window, and a roof window. The in-vehicle display device is not particularly limited, and examples thereof include a car navigation system, a display mounted on a television broadcast receiver, a monitor indicating the remaining amount of fuel, and the like. The type of the on-vehicle display device is not particularly limited as long as it has a display function, and examples thereof include a liquid crystal display device and an organic EL display device. In-vehicle display devices are usually placed in front of the cockpit and passenger seats, but in projection-type liquid crystal display devices that view images projected on the screen, the screen that is the display surface is usually the cockpit. Since the vehicle-mounted display device main body and the like may be disposed behind the cockpit and the passenger seat. Note that a direct-viewing type liquid crystal display device or the like that directly looks at the display may have a function that enables different displays at the same time between the cockpit and the passenger seat, for example. It does not specifically limit as a vehicle, A motor vehicle, a two-wheeled motor vehicle, a train, etc. are mentioned.

As long as the vehicle of the present invention includes the window and the in-vehicle display device as components, the vehicle may or may not include other components, and is not particularly limited.

The window is preferably a front side window. The display surface of the in-vehicle display device is usually arranged in front of the cockpit or the passenger seat. Therefore, according to this, since the front side window can block the S-polarized light component having high reflectivity in the front side window, the reflection of external light from the cockpit or passenger seat to the display surface is visually recognized. Can be effectively suppressed. In this specification, the front side window refers to a side window disposed at the front portion of the vehicle, and generally refers to a side window disposed beside the cockpit and / or passenger seat.

The present invention further includes a vehicle including a window and an in-vehicle display device having a display surface, wherein the vehicle is used for in-vehicle use when natural light is transmitted toward the display surface of the in-vehicle display device. A film that selectively blocks a polarized component that vibrates substantially parallel to the display surface of the display device is also a vehicle attached to a window. That is, the present invention further includes a vehicle including a window and a vehicle-mounted display device having a display surface, wherein the vehicle includes a natural light when the natural light is transmitted toward the display surface of the vehicle-mounted display device. A film that selectively transmits a polarized component that vibrates substantially perpendicularly to the display surface of the in-vehicle display device is also a vehicle that is attached to a window. According to this aspect, the S-polarized component having a high reflectance is blocked by the film attached to the window, and the S-polarized component reaching the display surface of the in-vehicle display device is reduced. Reflection of external light on the surface can be suppressed.

Although the said film may be affixed on the outer side (outside of a vehicle) with respect to a window, it is preferable to affix on the inner side (inner side of a vehicle) from a durable viewpoint. Also, the method of attaching is not particularly limited, and when the film has adhesiveness, it may be attached directly to the window using the adhesiveness, and the film does not have adhesiveness. Etc., may be attached via an adhesive layer such as an adhesive layer.

As long as the vehicle of the present invention includes the film, the window, and the on-vehicle display device as components, the vehicle may or may not include other components, and is not particularly limited.

The film is preferably attached to the front side window. According to this, since the S-polarized component having a high reflectance is blocked by the film attached to the window, the display surface of the in-vehicle display device is arranged in front of the cockpit and the passenger seat. It is possible to suppress the appearance of external light reflected on the display surface from the cockpit or passenger seat.

According to the transparent member for preventing reflection of external light according to the present invention, when natural light is transmitted toward the display surface of the display device, the polarized light component that vibrates substantially parallel to the display surface of the display device among the natural light ( Since the S-polarized component) can be selectively blocked, the reflection of external light on the display surface can be suppressed. As a result, the visibility of the display device can be improved.

Hereinafter, the present invention will be described in more detail with reference to embodiments, but the present invention is not limited only to these embodiments.

(Embodiment 1)
FIG. 1 is a schematic plan view showing a state when an interior of an automobile according to Embodiment 1 of the present invention is observed from above.
In the automobile (structure) according to the present embodiment, as shown in FIG. 1, a direct-view type in-vehicle liquid crystal display device 12 is disposed in front of the driver seat and the passenger seat. The external light (natural light) 10 includes a P-polarized component (a polarization component whose light vibration plane is perpendicular to the display surface of the vehicle-mounted liquid crystal display device 12) 10P and an S-polarized component (a light vibration surface is the vehicle-mounted liquid crystal display device 12). The polarization component parallel to the display surface) 10S.

FIG. 2 is a graph showing the incident angle dependence of the reflectance of general P-polarized light components and S-polarized light components.
As shown in FIG. 2, generally for light, the S-polarized component tends to have a higher reflectance than the P-polarized component. Such characteristics are no exception for the P-polarized component 10P and the S-polarized component 10S in the present embodiment.

In this embodiment, a polarizing film (transparent member for preventing external light reflection) 14 that blocks the S-polarized component 10S and transmits only the P-polarized component 10P is attached to the inside of the front side window 11 on the passenger seat side. Yes. Therefore, as shown in FIG. 1, since only the P-polarized component 10P having a low reflectance is incident on the display surface of the in-vehicle liquid crystal display device 12, the driver 13 applies to the display surface of the in-vehicle liquid crystal display device 12. The reflection of outside light is not visually recognized.

It is a plane schematic diagram which shows a mode when the inside of the motor vehicle which concerns on Embodiment 1 of this invention is observed from the top. It is a plane schematic diagram which shows a mode when the inside of the conventional motor vehicle is observed from the top. It is a graph which shows the incident angle dependence of the reflectance of a general P polarization component and a S polarization component. The angle at which the reflectance of the P-polarized component becomes 0 is the polarization angle (Brewster angle).

Explanation of symbols

10: Outside light (natural light)
10P: P polarization component 10S: S polarization component 11: Front side window 12: In-vehicle liquid crystal display device (in-vehicle display device)
13: Driver 14: Polarizing film (transparent member for preventing reflection of external light)
51: Front side window

Claims (5)

A transparent member for preventing external light reflection used in a structure in which a display device having a display surface is arranged,
The transparent member for preventing reflection of external light selectively blocks polarized light components that vibrate substantially parallel to the display surface of the display device from the natural light when natural light is transmitted toward the display surface of the display device. A transparent member for preventing reflection of outside light. A vehicle comprising a window and an in-vehicle display device having a display surface,
When the natural light is transmitted toward the display surface of the in-vehicle display device, the window selectively blocks a polarization component that vibrates substantially parallel to the display surface of the in-vehicle display device. Characteristic vehicle. The vehicle according to claim 2, wherein the window is a front side window. A vehicle comprising a window and an in-vehicle display device having a display surface,
The vehicle has a film that selectively blocks a polarized component that vibrates substantially parallel to the display surface of the in-vehicle display device among the natural light when natural light is transmitted toward the display surface of the in-vehicle display device. A vehicle characterized by being attached to a window. The vehicle according to claim 4, wherein the film is attached to a front side window.

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