CN1942819A - Anti-glare reflective and transmissive devices - Google Patents

Abstract

Devices that include a dichroic material sandwiched between first and second electrodes layers and exhibiting a high optical absorption when the first and second electrode layers are biased at a first electrical bias state and a low optical absorption when the first and second electrode layers are biased at a second, different electrical bias state. Such devices may be used to construct optically reflective devices such as anti-glare mirrors and optically transmissive devices such as eye glasses. The dichroic material may be selected to be operable to switch between the high optical absorption and the low optical absorption in less than 0.1 second.

Description

Anti-glare reflective device and transmissive device

This application claims the benefit of US Provisional Application No. 60/667,306, filed March 31, 2005, entitled "Anti-Glare Mirrors," and the entire contents of which application are incorporated herein by reference.

technical field

This application relates to anti-glare mirrors for a variety of applications including sunglasses, automotive rear view mirrors and side view mirrors.

Background technique

Many automotive mirrors include a glass substrate, a metal film plated on the substrate, and a dielectric protective film formed on the metal film, and according to specific application requirements, the mirror has different values of High light reflectivity. Thus, for example, when the sun is shining behind the vehicle or the rear headlights are shining at night, the reflected glare caused by the rear-view or side-view mirrors based on this design can temporarily blind the driver of the vehicle. This reflected glare can make the driver uncomfortable and can also lead to dangerous driving situations.

In order to alleviate the reflected glare, various glare-reducing mirrors have been developed and put on the market. Some designs can switch reflection from high to low reflectance to reduce glare. Various liquid crystal materials have also been used to produce varying reflectivity. See, for example, US Patent Nos. 3,614,210 and 4,696,548. However, various liquid crystal-based mirrors suffer from certain limitations in the fabrication process and have not yet achieved commercial mass production. Electrochromic layer materials have been used in antiglare mirror assemblies and are already in commercial production. One example of an anti-glare mirror employing an electrochromic layer material is described in US Patent No. 6,023,364.

Contents of the invention

The present application particularly discloses such a device comprising: a first electrode layer; an optically transparent second electrode layer; a dichroic material sandwiched between the first and second electrode layers, when the first and second electrodes The dichroic material exhibits higher light absorption when the layers are in a first electrical bias state, and when the first and second electrode layers are in a second electrical bias state different from the first electrical bias state, the dichroic material exhibits higher light absorption. The dichroic material exhibits low light absorption; and a control circuit coupled to the first and second electrode layers is operable to control an electrical bias between the first and second electrode layers, thereby controlling the dichroic Light absorption of colored materials. Such devices can be used to construct light-reflecting devices such as anti-glare mirrors and light-transmitting devices such as eyeglasses. The dichroic material can be selected to be able to switch between higher light absorption and lower light absorption in less than 0.1 second.

In one embodiment, there is provided an anti-glare mirror comprising: a metal layer that reflects light; a light transparent conductive layer; a dichroic layer sandwiched between the metal layer and the conductive layer, when additional electrically controlled The dichroic layer has a higher light absorption when no additional electrical control is used, the dichroic layer has a lower light absorption; and the control circuit coupled to the metal layer and the conductive layer can be Electrical control is operatively applied to the dichroic material. The dichroic material can switch between higher light absorption and lower light absorption in less than 0.1 second.

In another embodiment, there is provided an anti-glare mirror comprising: a metal layer that reflects light; a light transparent conductive layer; a dichroic layer sandwiched between the metal layer and the conductive layer, with or without The dichroic layer has high light absorption when externally controlled electrically, and the dichroic layer has low light absorption when the electric control voltage is applied or turned off; and the control coupled to the metal layer and the conductive layer, operable ground to apply electrical control to the dichroic material. The dichroic material can switch between higher light absorption and lower light absorption in less than 0.1 second.

In another embodiment, an anti-glare mirror is provided, comprising: an at least partially optically transparent first electrode layer; an at least partially optically transparent second electrode layer sandwiched between the first electrode layer and the second electrode layer The dichroic material that enters, when the first and second electrode layers are in the first electrical bias state, the dichroic material exhibits higher light absorption, when the first and second electrode layers are in a state different from the first electrical bias The dichroic material exhibits lower light absorption during the second electrical bias state of the set state; a control circuit coupled to the first and second electrode layers, operable to control the electrical connection between the first and second electrode layers a bias, thereby controlling light absorption of the dichroic material; and a reflective layer configured to receive light passing through the first electrode, the second electrode, and the dichroic material and reflect the received light back. The dichroic material can be selected to be able to switch between higher light absorption and lower light absorption in less than 0.1 second.

These and other embodiments are described in more detail in the drawings, detailed description, and claims.

Description of drawings

Figure 1 shows the sandwich structure of an anti-glare mirror employing an electrically controlled dichroic mixing layer that changes light absorption in response to a voltage applied across it.

Detailed ways

The inventors have realized that optical density recovery times in electrochromic layer materials are often longer, for example greater than a few seconds. This lower response could potentially create a dangerous situation for the driver caused by the reflected glare. Furthermore, in some anti-glare mirrors employing electrochromic layer materials, the spectral response of the electrochromic layer materials can cause the darkened mirror with electrochromic layer materials to appear green. A greenish tint to the reflected image is unnatural and undesirable. Anti-glare mirrors require fast response times and images with a natural grayscale appearance.

The present application describes various embodiments of anti-glare mirrors employing a light absorbing material having adjustable absorption in response to an electrical control signal. In one embodiment, an anti-glare mirror comprises a film of dichroic material or a film of dichroic hybrid material sandwiched between a highly reflective metal surface and a transparent conductive front electrode. The dichroic material or dichroic hybrid material has low absorption when light passes in a direction perpendicular to the elongated molecular axis of the material, and when light travels along the long axis of the molecule, the The above-mentioned dichroic material or dichroic mixed material has higher absorption. By applying an electric field, a lower absorbing state can be switched to a higher absorbing state and vice versa. Properly formulated dichroic materials or dichroic hybrid materials can have relatively fast switching speeds, eg, less than 0.1 second, when switching between a higher absorbing state and a lower absorbing state. In addition, the absorption of this material is insensitive to wavelength, and thus has essentially equal absorption for visible wavelengths of light. This broadband spectral absorption of the dichroic material or dichroic hybrid material produces a natural appearance in the darkened mirror reflection. A variety of dichroic materials or dichroic hybrid materials can be used. Mirrors with dichroic materials or dichroic hybrid materials can advantageously be used as rear or side view mirrors capable of faster response times, for example, less than a tenth of the Seconds, and can form natural grayscale black and white images in anti-glare state and anti-glare state. Dichroic dyes can be employed, if desired, to deliberately produce a desired hue in the reflection of the anti-glare mirror. When the mirror is darkened, different dichroic dyes can be used to achieve different shades.

FIG. 1 shows an example of an anti-glare mirror using a dichroic material or a dichroic hybrid material. Layer 1 is the backing substrate and can consist of an opaque or transparent material. Layer 2 is a metallic coating that is part of the electrical control mechanism of the mirror, which may be partially or fully reflective. Layer 3 is a dielectric coating interfaced with layer 4 of the dichroic mixture material. The layer 4 of dichroic mixture material responds to an electrical control signal (eg a control voltage) to change its light absorption and thus the degree of reflection of the mirror. Examples of suitable materials for the layer 4 of dichroic mixed material include dichroic dyes, such as anthraquinone dyes. More specific examples include dichroic dyes AG1, AR1 and AB3 produced by Nematel, Germany. On the other side of the layer 4 of dichroic mixture material a second dielectric coating 5 is provided such that the layer 4 is sandwiched between two dielectric layers 3 and 5 . On top of the dielectric layer 5 a transparent electrode coating 6 (eg ITO) is employed as part of the electrical control mechanism of the mirror. The electrical control signal is applied to the electrode coatings 6 and 2 to control and vary the voltage across the layer 4 of dichroic mixture material. Furthermore, a front transparent substrate 7 (eg a glass substrate) may be placed on top of the electrode layer 6 . An electrical control circuit may include an electrical switch 9 controlled by incident light and a power source 10, said electrical control circuit being electrically connected to electrodes 2 and 6 to provide an electrical control signal. The electric switch 9 can be realized by various photosensitive switches using light sensors, and the threshold light intensity triggering the switch operation can be set by design based on the special requirements of the application using the anti-flash mirror. One or more light detectors may be included as part of the switch 9 and may eg be mounted on the rear of the metal coating 2 to measure incident light. In some embodiments, the power source 10 may be an adjustable AC power source between 2-11V.

In actual operation, light is incident on the mirror in FIG. 1 through the front transparent substrate 7, passes through the layer 4 of dichroic mixture material and is reflected so as to pass through the layer 4 of dichroic mixture material again. When the incident light received by the mirror reaches or exceeds the threshold light intensity of the photosensitive switch 9, the AC power between the metal layer 2 and the front electrode 6 is turned on (or turned off for different dichroic materials) so that the dichroic The chromotropic layer 4 works in a higher absorption state to reduce reflected light. Otherwise, the dichroic layer 4 is set to a lower absorbing state. The absorption in the dichroic layer 4 is regulated and controlled by the control voltage. This adjustment can be used to provide different comfortable visual conditions for different drivers.

The mirror in Figure 1 can be further configured to include a display window made of LCD or LED to display different information such as turn signal, compass and temperature.

In a particular implementation, the material used for the dichroic layer 4 can be chosen so that when no voltage is applied across the layer 4, a lower absorbing state is achieved. Optionally, the mirror in Figure 1 can also employ dichroic materials or dichroic hybrids that have higher light absorption when the control voltage is off and lower light absorption when the control voltage is on. Material.

The sandwich structure of the anti-glare mirror in Fig. 1 can be improved to construct anti-glare transmissive devices such as anti-glare glasses and sunglasses. In an anti-glare transmissive device, the back substrate 1 and the back electrode layer 2 are made of transparent materials so that light can pass through the entire structure. Such structures can be used in a variety of applications and could be, for example, sunglass structures. A small battery can be used as the power source 10, so that glasses and sunglasses with this design are light and small.

In an alternative embodiment, the metal layer 2 can be used as a light reflecting surface while an additional transparent electrode layer is placed between the metal layer 2 and the layer 4 of the dichroic mixture material so that the layer 4 of the dichroic mixture material placed between the additional transparent electrode layer and the transparent electrode layer 6 . Then, a control voltage is applied between the two transparent electrode layers.

In general, only a few embodiments are described here. However, it should be understood that various changes and modifications can be made thereto.

Claims (20)

1. antiglare mirror comprises:

First electrode layer;

The second electrode lay of optical transparency;

The dichroic material, it is sandwiched between described first electrode layer and the described the second electrode lay, when described first electrode layer and described the second electrode lay are in the first electrical bias state, described dichroic material presents higher light absorption, when described first electrode layer and described the second electrode lay are in the second electrical bias state that is different from the described first electrical bias state, described dichroic material presents lower light absorption, wherein, described dichroic material switching time of changing between higher light absorption and lower light absorption was less than 0.1 second; And

Control circuit, it is coupled to described first electrode layer and described the second electrode lay, and operationally controls the electrical bias between described first electrode layer and the described the second electrode lay, and then controls the light absorption of described dichroic material.

2. antiglare mirror as claimed in claim 1, wherein, described control circuit further comprises sensor, when described mirror receive wide during in threshold intensity, described sensor causes the described first electrical bias state to be used, the light that receives when described mirror is during less than threshold intensity, and described sensor causes the described second electrical bias state to be used.

3. antiglare mirror as claimed in claim 2, wherein, described sensor comprises and is installed in described metallic coating back to measure one or more photo-detectors of incident light.

4. antiglare mirror as claimed in claim 1, wherein said the second electrode lay is made of ITO.

5. antiglare mirror as claimed in claim 4 further is included in the additional dielectric layer between described ITO layer and the described dichroic material.

6. antiglare mirror as claimed in claim 1, wherein said dichroic material comprises the dichroic liquid crystal compound.

7. antiglare mirror as claimed in claim 1, wherein said dichroic material comprises dichroic dyestuff.

8. antiglare mirror as claimed in claim 1, wherein said first electrode layer are partial reflection light at least.

9. antiglare mirror as claimed in claim 1, wherein, the described first electrical bias state is the state that voltage is applied to described dichroic material, and the described second electrical bias state is the state that voltage is not applied to described dichroic material.

10. antiglare mirror as claimed in claim 1, wherein, described second bias state is the state that voltage is applied to described dichroic material, and the described first electrical bias state is the state that voltage is not applied to described dichroic material.

11. glasses comprise:

First electrode layer of optical transparency;

The second electrode lay of optical transparency;

The dichroic material, it is sandwiched between described first electrode layer and the described the second electrode lay, when described first electrode layer and described the second electrode lay are in the first electrical bias state, described dichroic material presents higher light absorption, when described first electrode layer and described the second electrode lay were in the second electrical bias state that is different from the described first electrical bias state, described dichroic material presented lower light absorption; And

Control circuit, it is coupled to described first electrode layer and described the second electrode lay, and operationally controls the electrical bias between described first electrode layer and the described the second electrode lay, and then controls the light absorption of described dichroic material.

12. glasses as claimed in claim 11, wherein, described control circuit further comprises sensor, when described mirror receive wide during in threshold intensity, described sensor causes the described first electrical bias state to be used, the light that receives when described mirror is during less than threshold intensity, and described sensor causes the described second electrical bias state to be used.

13. glasses as claimed in claim 11, wherein said first electrode layer and described the second electrode lay are made of ITO.

14. glasses as claimed in claim 11, wherein said dichroic material comprises the dichroic liquid crystal compound.

15. glasses as claimed in claim 11, wherein said dichroic material comprises dichroic dyestuff.

16. glasses as claimed in claim 11, wherein, the described first electrical bias state is the state that voltage is applied to described dichroic material, and the described second electrical bias state is the state that voltage is not applied to described dichroic material.

17. glasses as claimed in claim 11, wherein, described dichroic material operationally in less than 0.1 second, is changed between described higher light absorption and described lower light absorption.

18. an antiglare mirror comprises:

At least first electrode layer of partially transparent and the second electrode lay of partially transparent at least;

The dichroic material, it is sandwiched between described first electrode layer and the described the second electrode lay, when described first electrode layer and described the second electrode lay are in the first electrical bias state, described dichroic material presents higher light absorption, when described first electrode layer and described the second electrode lay were in the second electrical bias state that is different from the described first electrical bias state, described dichroic material presented lower light absorption;

Control circuit, it is coupled to described first electrode layer and described the second electrode lay, and operationally controls the electrical bias between described first electrode layer and the described the second electrode lay, and then controls the light absorption of described dichroic material; And

The reflection horizon, it is set to receive the light by described first electrode, described second electrode and described dichroic material, and the light that is received is reflected back.

19. antiglare mirror as claimed in claim 18, wherein said dichroic material operationally in less than 0.1 second, are changed between described higher light absorption and described lower light absorption.

20. antiglare mirror as claimed in claim 18, wherein said dichroic material comprises dichroic dyestuff.